Showing papers in "Journal of Experimental Medicine in 1969"
TL;DR: It was found that the proportion of individuals with serum bactericidal activity to meningococci of serogroups A, B, and C was reciprocally related to the incidence of disease, and susceptible persons are deficient in antimeningococcal antibodies because they have not received significant exposure to mena antigens in the past.
Abstract: Susceptibility to systemic meningococcal disease is related to a selective deficiency of humoral antibodies to pathogenic strains of meningococci. In a study of the age-specific incidence of meningococcal meningitis in the United States, it was found that the proportion of individuals with serum bactericidal activity to meningococci of serogroups A, B, and C was reciprocally related to the incidence of disease. The prevalence of bactericidal activity was highest at birth and among adults, and lowest in infants between 6 and 24 months of age. Sera from 51 of 54 prospective cases of meningococcal disease among military recruits were deficient in antibodies to homologous and heterologous strains of pathogenic meningococci as determined by serum bactericidal activity and indirect immunofluorescence. Such sera, however, could support the bactericidal activity of purified human gamma globulin (Cohn fraction II), and such individuals could respond immunologically to infection with meningococci. The implication is that susceptible persons are deficient in antimeningococcal antibodies because they have not received significant exposure to meningococcal antigens in the past. The fate of individuals who lack bactericidal antibodies to pathogenic meningococci was determined during an outbreak of group C meningitis among military recruits. The incidence of disease was found to be primarily associated with the incidence of exposure of susceptibles to the pathogenic strains. Whereas 81.5% of the presumed susceptibles acquired a meningococcal strain, only 24.1% acquired an organism similar to the prevalent disease-producing strains. Of the exposed susceptibles, 38.5% developed systemic meningococcal disease.
1,277 citations
TL;DR: Results of the present study suggest that natural immunity to meningococcal disease is initiated, reinforced, and broadened by intermittent carriage of different strains ofMeningococci throughout life.
Abstract: Results of the present study suggest that natural immunity to meningococcal disease is initiated, reinforced, and broadened by intermittent carriage of different strains of meningococci throughout life. In young adults, carriage of meningococci in the nasopharynx is an efficient process of immune sensitization. 92% of carriers of serogroup B, C, or Bo meningococci were found to develop increased titers of serum bactericidal activity to their own meningococcal isolate, and 87% developed bactericidal activity to heterologous strains of pathogenic meningococci. The rise in bactericidal titer occurred within 2 wk of onset of the carrier state, and was accompanied by an increase in titer of specific IgG, IgM, and IgA antibodies to meningococci. In early childhood, when few children have antibodies to pathogenic meningococci, active immunization seems to occur as a result of carriage of atypical, nonpathogenic strains. Immunity to systemic meningococcal infection among infants in the neonatal period is associated with the passive transfer of IgG antibodies from mother to fetus. The antigenic determinants which initiate the immune response to meningococci include the group-specific C polysaccharide, cross-reactive antigens, and type-specific antigens.
1,028 citations
TL;DR: It has been shown that the immune response of mice to infection with L. monocytogenes gives rise to a population of immunologically committed lymphoid cells which have the capacity to confer protection and a proportionate level of delayed-type hypersensitivity upon normal recipients.
Abstract: It has been shown that the immune response of mice to infection with L. monocytogenes gives rise to a population of immunologically committed lymphoid cells which have the capacity to confer protection and a proportionate level of delayed-type hypersensitivity upon normal recipients. The cells were most numerous in the spleen on the 6th or 7th day of infection, but persisted for at least 20 days. Further study revealed that the immune cells must be alive in order to confer protection, and free to multiply in the tissues of the recipient if they are to provide maximum resistance to a challenge infection. The antibacterial resistance conferred with immune lymphoid cells is not due to antibacterial antibody; it is mediated indirectly through the macrophages of the recipient. These become activated by a process which appears to depend upon some form of specific interaction between the immune lymphoid cells and the infecting organism. This was deduced from the finding that immune lymphoid cells from BCG-immunized donors, which were highly but nonspecifically resistant to Listeria, failed to protect normal recipients against a Listeria challenge unless the recipients were also injected with an eliciting dose of BCG. The peritoneal macrophages of animals so treated developed the morphology and microbicidal features of activated macrophages. It is inferred that acquired resistance depends upon the activation of host macrophages through a product resulting from specific interaction between sensitized lymphoid cells and the organism or or its antigenic products. Discussion is also made of the possibility that activation of macrophages could be dependent upon antigenic stimulation of macrophages sensitized by a cytophilic antibody.
914 citations
TL;DR: Immunohistochemical data indicate that lactoferrin first appears in myeloid cells at the stage of the promyelocyte, and the identification of this protein in leukocyte extracts was based upon a comparison of its electrophoretic, antigenic, and iron-combining properties with the corresponding properties of the same protein isolated from human and guinea pig milk.
Abstract: Lactoferrin, an iron-binding protein previously shown to occur in many external secretions, is identified as one of the major proteins present in human and guinea pig neutrophilic polymorphonuclear leukocytes.
The identification of this protein in leukocyte extracts was based upon a comparison of its electrophoretic, antigenic, and iron-combining properties with the corresponding properties of the same protein isolated from human and guinea pig milk. Immunochemical quantitations showed that lactoferrin occurs in human neutrophilic leukocytes at the concentration of 3 µg per 106 cells. Tissue cultures from guinea pig bone marrow and spleen actively synthesized the protein, as shown both by net production of lactoferrin and incorporation of labeled amino acids into the protein. Immunohistochemical data indicate that lactoferrin first appears in myeloid cells at the stage of the promyelocyte.
641 citations
TL;DR: The high molecular weight group A and group C meningococcal polysaccharides were excellent immunogens in six human volunteers and were highly meningococcocidal in the presence of complement.
Abstract: High molecular weight group A and group C meningococcal polysaccharides had no significant toxicity for mice or guinea pigs. Furthermore, these polysaccharide preparations contained negligible amounts of biologically active endotoxin. The high molecular weight group A and group C meningococcal polysaccharides were excellent immunogens in six human volunteers. Antibodies belonging to the immunoglobulin classes IgG, IgM, and IgA were produced. These antibodies were highly meningococcocidal in the presence of complement.
410 citations
TL;DR: It was concluded that C3a corresponds to an unusually basic portion of C3 which may be liberated by attack of a variety of enzymes on a highly susceptible region of the native C3 molecule.
Abstract: A small fragment of C3, called C3a, which has smooth muscle contracting activity, was isolated by three different methods. At pH 8.6, C3a behaved as cation, and using the Archibald method, its mol wt was determined to be 7000. A specific antiserum to C3a showed the fragment to be antigenically distinct from the rest of the C3 molecule, i.e., the C3b portion. The same antiserum and an anti-whole C3 were able to inhibit the biologic activity of C3a. In addition to anaphylatoxin activity, leukocyte chemotactic activity was shown to reside in C3a. Treatment with trypsin caused the cationic fragment to become anionic and abolished the anaphylatoxin but not the chemotactic activity. C3a fragments with identical biologic activity and comparable cationic properties, as determined by acid disc electrophoresis, were obtained by treatment of C3 with C3 convertase, C3 inactivator complex, trypsin, and plasmin. Thrombin produced a similar C3 fragment which was inactive. It was concluded that C3a corresponds to an unusually basic portion of C3 which may be liberated by attack of a variety of enzymes on a highly susceptible region of the native C3 molecule. C3b was cleaved by trypsin and less efficiently by thrombin or plasmin into two antigenically distinct pieces: the larger C3c fragment corresponding to beta(1A) and the smaller C3d fragment to alpha(2D) of aged serum. The c- and the d-fragments were separated and characterized. Isolated C3a rapidly lost its anaphylatoxin activity when treated with small amounts of a partially purified, thermolabile 10S alpha-pseudoglobulin of human serum. The conditions of inactivation suggested an enzymatic reaction. The anaphylatoxin inactivator also destroyed the activity of C5-derived anaphylatoxin and of lysyl bradykinin.
392 citations
TL;DR: A passive hemagglutination test developed to measure antibodies to the polysaccharides demonstrated the specificity of these antigens, and this test could be used for serogrouping meningococcal isolates.
Abstract: The group-specific polysaccharides of group A and group C meningococci have been isolated by a new procedure which employs the cationic detergent Cetavlon to precipitate these polysaccharides from the whole culture. The A and C polysaccharide prepared by this method are noteworthy because they are of high molecular weight. The main constituent of the A polysaccharide is N-acetyl, O-acetyl mannosamine phosphate; of the C polysaccharide N-acetyl, O-acetyl neuraminic acid. This purification procedure, when applied to cultures of group B organisms, yields a polysaccharide consisting primarily of N-acetyl neuraminic acid. A passive hemagglutination test developed to measure antibodies to the polysaccharides demonstrated the specificity of these antigens. Using a hemagglutination inhibition test, these antigens were again found to be group-specific, and this test could be used for serogrouping meningococcal isolates.
391 citations
TL;DR: Based upon physical-chemical and antigenic characteristics, the 16.7S immunoglobulin most closely resembles IgM of mammals, and it is proposed that this molecule be designated as IgY.
Abstract: Chicken 7.1S immunoglobulin was purified from whole chicken serum by DEAE-cellulose chromatography and Sephadex G-200 gel filtration. The macroglobulin was purified by a combination of salt precipitation and Sephadex G-200 gel filtration. Both immunoglobulin molecules yielded 75% heavy (H) chains and 25% light (L) chains when subjected to extensive reduction and alkylation followed by gel filtration in 5 M guanidine-HCl. Antigenically reactive H and L chains were obtained by partial reduction and alkylation followed by gel filtration in 5 M guanidine-HCl. The 7.1S and 16.7S immunoglobulin H chains were antigenically unrelated to each other, whereas the L chains were antigenically indistinguishable from one another. The 16.7S H chains were found to have a mass of ∼70,000, and the 7.1S H chains had a mass of 67,500. The mass of the L chains was ∼22,000. Sedimentation equilibrium studies of the 7.1S immunoglobulin molecule gave a mol wt of ∼170,000 which is in good agreement with the 179,000 predicted on the basis of 2 H and 2 L polypeptide chains. The 16.7S molecule was shown to have a mol wt of ∼890,000. A reductive subunit that has a mol wt of ∼174,000 has been isolated from the 16.7S molecule. These values are consistent with the chicken macroglobulin having five subunits, each of which has 2 H and 2 L chains. The hexose contents of the chicken 7.1S and 16.7S immunoglobulins are 2.2% and 2.6%, respectively. The extinction coefficients of the 7.1S and 16.7S immunoglobulins were 13.18 ± 0.04 and 12.72 ± 0.77, respectively, when measured in 0.3 M KCl. Based upon physical-chemical and antigenic characteristics, the 16.7S immunoglobulin most closely resembles IgM of mammals. The 7.1S immunoglobulin definitely belongs to a different class than the 16,7S immunoglobulin, but it does not align itself very well with any of the mammalian immunoglobulins. We propose that this molecule be designated as IgY. Furthermore, this designation would be useful for the immunoglobulins of other species for which there is insufficient correlation with any of the known human immunoglobulins.
351 citations
TL;DR: The immune stimulus leading to antibody formation requires the interaction of two antigen-bridged cells and it is suggested that the receptors for recognition of unrelated determinants are probably situated on different cells.
Abstract: Rabbits primarily stimulated with a BSA (bovine serum albumin)-sulfanilic acid complex will produce a good secondary response to the sulfanilic acid hapten if the carrier used in the secondary stimulus is again BSA, and not if the secondary carrier is HGG (human gamma globulin). In the latter situation, a good secondary response is obtained, however, if the rabbits are pretreated a few weeks earlier with free HGG. We conclude that the immune stimulus involves the recognition of carrier determinants unrelated to the hapten. As the receptors for recognition of unrelated determinants are probably situated on different cells, we suggest that the immune stimulus leading to antibody formation requires the interaction of two antigen-bridged cells.
347 citations
TL;DR: More detailed studies will permit a better assessment of the importance of these three possible regulatory roles of the Fc portion of the immunoglobulin in the immune response.
Abstract: The ability of 7S and F(ab')2 antibody fragments to suppress priming with low doses of antigen was compared. The 7S preparation was approximately 100–1000 times more potent than the F(ab')2 preparation when the agglutinin titers of the two preparations were the same. The presence of any ability to suppress priming in the F(ab')2 preparation may reflect an inherent capacity of the F(ab')2 antibody or contamination with small amounts of 7S antibody. The difference between 7S and F(ab')2 antibody in ability to suppress priming is attributed to the lack of the Fc portion on the F(ab')2 antibody. The Fc portion may be needed to prevent rapid excretion of antibody from the body, to induce rapid phagocytosis of antigen-antibody complexes with consequent breakdown and elimination of antigen, or to inactivate or suppress the antigen-sensitive cells from reacting to antigenic determinants. More detailed studies will permit a better assessment of the importance of these three possible regulatory roles of the Fc portion of the immunoglobulin in the immune response.
322 citations
TL;DR: The immunohistological localization of γA, secretory "piece" (SP), and lactoferrin (LF) in the mucosae of a variety of normal human tissues was investigated using specific fluoresceinated antisera to propose a hypothetical model for the transport ofγA and SP across mucosal membrane epithelium.
Abstract: The immunohistological localization of γA, secretory "piece" (SP), and lactoferrin (LF) in the mucosae of a variety of normal human tissues was investigated using specific fluoresceinated antisera. γA staining was localized in the apical portion of the mucosal epithelium, intercellular spaces, basement membrane area, and plasma cells of the interstitium or lamina propria of a number of normal human tissues. SP was ubiquitous in the mucosal epithelium of all tissues studied which included parotid and submaxillary glands, bronchi, pancreas, GI tract, sweat glands, kidney, and gall bladder. In addition, SP staining was localized in the intercellular spaces and on the surface of the epithelial cells lining the lumen of the secretory glands. No SP staining was observed in the plasma cells of the interstitium or lamina propria surrounding the secretory glands in these tissues, and no SP staining was observed in sections of normal spleen or lymph node tissue. SP staining was observed in the sweat glands, pancreas, and kidney in the absence of γA staining. LF was much less ubiquitous in the epithelial cells of the various tissues studied and appeared to be restricted primarily to the acinar epithelium of the bronchial mucosae, parotid, and submaxillary salivary glands, and was also found in renal tubular cells. A hypothetical model for the transport of γA and SP across mucosal membrane epithelium is presented.
TL;DR: Observations indicate that choleragenicity and increased vascular permeability are intimately associated phenomena and may be manifestations of the same basic mechanism.
Abstract: Choleragen, a diarrheagenic protein enterotoxin elaborated by Vibrio cholerae, has been isolated from the supernate of fermenter cultures by steps involving ammonium sulfate precipitation, DEAE cellulose, Sephadex G-75, and Agarose A-5m chromatography. The resulting product appears to be pure according to immunoelectrophoretic, disc electrophoretic, ultracentrifugal, and immunologic criteria. Sephadex gel filtration and membrane filtration studies suggest a molecular size of 61,000. The isolated product is highly active in inducing experimental cholera in infant and adult rabbit models. It also elicits, in small dosage, an increased vascular permeability in skin. These observations indicate that choleragenicity and increased vascular permeability are intimately associated phenomena and may be manifestations of the same basic mechanism. An additional, antigenically identical, protein has also been isolated by the same procedures. The latter substance, termed "choleragenoid", lacks the permeability effect and choleragenicity of the choleragen moiety. Its size (estimated from Sephadex gel filtration at 42,000) is smaller than that of choleragen and it also differs in charge. Choleragenoid may prove useful as a nontoxic immunogen to protect against pathologic effects of V. cholerae infection.
TL;DR: Results obtained support the concept of a cell-associated antigen-specific receptor being present on the outer surface of immune cells, displaying the same antigen-binding specificity as the potential product of the cell, the humoral antibody.
Abstract: Glass and plastic bead columns coated with antigenic protein molecules were used as an immunological filter for cell populations containing immune cells of relevant specificity. A selective elimination of these immune cells from the passing cell suspension was regularly noted and it approached, in some experiments, complete abolition of the specific immune reactivity of the filtered cell population. This specific retention of immune cells by antigenic columns could be selectively blocked by the presence of free antigen molecules in the medium during filtration. The results obtained support the concept of a cell-associated antigen-specific receptor being present on the outer surface of immune cells, displaying the same antigen-binding specificity as the potential product of the cell, the humoral antibody. Using the present bead column system, results were obtained indicating that this receptor was an active product of the immune cells and not any passively adsorbed, cytophilic antibody. Antigenic bead columns may very well constitute a tool for the production in vitro of cell populations being specifically deprived of immune reactivity and allow detailed analysis of the characteristics of the cell-associated antibody of immune cells.
TL;DR: C'1 esterase inhibitor has been found to block the actions of plasmin and the C'1r subcomponent of the first component of complement, and to retard the generation of PF/Dil.
Abstract: The fraction of human serum designated as C'1 esterase inhibitor is known to inhibit the action of C'1 esterase, a plasma kallikrein, and PF/Dil, an enzyme in plasma enhancing cutaneous vascular permeability. In the present study, C'1 esterase inhibitor has been found to block the actions of plasmin and the C'1r subcomponent of the first component of complement, and to retard the generation of PF/Dil. No inhibition of blood clotting or of the generation of plasmin was demonstrable.
TL;DR: Thymic rudiments from chick and mouse embryos have been cultured in diffusion chambers on the chick chorioallantois and it is concluded that an inflow of stem cells continues once full lymphopoiesis has begun, although perhaps at a reduced rate.
Abstract: Thymic rudiments from chick and mouse embryos have been cultured in diffusion chambers on the chick chorioallantois. In this situation their supply of blood-borne stem cells is cut off. Although rudiments from older embryos become fully lymphoid under these circumstances, primordia from early embryos fail to develop any lymphoid cells. Early chick rudiments will however develop completely if they are grafted directly to the chorioallantois where they receive a vascular supply. It is concluded that stem cells first enter the chick thymic anlage at between 6 and 7 days' incubation and the mouse thymic rudiment between 10 and 11 days' gestation. During the following few days of development there is a rapid inflow of stem cells to the rudiments. Since it is likely that stem cells, once they have entered the thymic primordium, are capable of only limited proliferation, it must be concluded that an inflow of stem cells continues once full lymphopoiesis has begun, although perhaps at a reduced rate. Finally, the importance of the interaction between stem cell and organ rudiment to normal thymic development is discussed in relation to the pathogenesis of thymic anomalies.
TL;DR: The results suggest that sialic acid constituents of the lymphocyte surface play a critical role in ensuring the normal distribution of these cells in the body and imply that reactions involving surface sIALic acid can markedly alter the fate of lymphocytes without "killing" the cells.
Abstract: Evidence has been obtained that incubation of rat lymphocytes with neuraminidase, prior to intravenous transfusion into allogeneic or syngeneic recipients, alters the distribution of the cells. Many enzyme-treated lymphocytes initially become trapped in the liver, and there is a decrease in the selective accumulation of these cells in the lymph nodes and spleen. Subsequently, many enzyme-altered cells emigrate from the liver, concentrate in lymph nodes, and recirculate to the lymph. The results suggest that sialic acid constituents of the lymphocyte surface play a critical role in ensuring the normal distribution of these cells in the body. The findings also imply that reactions involving surface sialic acid can markedly alter the fate of lymphocytes without "killing" the cells.
TL;DR: The transfer of anti-LCM antibody to SWR/J carrier mice results in acute necrotizing inflammatory lesions in regions of viral persistence, followed by chronic mononuclear infiltrates quite similar to those seen after the transfer of immune cells.
Abstract: Mice infected shortly after birth with lymphocytic choriomeningitis (LCM) virus are not immunologically tolerant, although they carry the virus throughout life. These LCM carrier mice make anti-LCM antibody, which apparently complexes with viral antigen in the circulation and these complexes accumulate in the glomeruli. LCM carrier mice of different strains vary significantly as to concentration of detectable infectious virus in their tissue, amount and time of appearance of anti-LCM antibody, and development of an associated chronic disease. The chronic disease consists primarily of glomerulonephritis, focal hepatic necrosis, and disseminated lymphoid infiltrations. LCM carriers of the SWR/J strain contain high tissue concentrations of virus, considerable anti-LCM antibody detectable in the glomeruli by 3 wk to 2 months of age and develop chronic disease within the first 2–3 months of life. In contrast, C3H strain LCM carriers contain 1/1000 as much infectious virus, less detectable anti-LCM antibody, and have not, over a 24 month observation period, developed any detectable disease. B10D2 old and new carrier mice with intermediate amounts of virus develop chronic disease during the latter half of the first year of life. The pathogenesis of the glomerulonephritis of chronic LCM disease is apparently related to the formation of circulating virus-antibody complexes which are trapped in the glomerular filter. There is no evidence for direct glomerular injury by the virus nor for any autoimmune response by the host.
TL;DR: When vaccinated mice were reinfected with BCG, host resistance in spleen and liver was rapidly augmented to the accompaniment of striking changes in the morphology and microbicidal activity of the peritoneal macrophages, resulting in the development of tuberculin sensitivity.
Abstract: Heterologous organisms (L. monocytogenes and S. typhimurium) were used to study the rate of development, magnitude, and persistence of the antimicrobial resistance engendered in mice by vaccination with BCG. These same methods were used to investigate the influence of prior vaccination on the host response to reinfection. The rate of onset and magnitude of the resistance produced by BCG varied with the vaccinating dose. Increased resistance was detected within 48 hr of injecting large numbers of BCG (approximately 10(8) viable units), but concurrent treatment with isoniazid interrupted its further development. An equal number of heat-killed organisms failed to influence host resistance significantly. The development of tuberculin sensitivity was also dependent upon the continued survival of the immunizing population of BCG. When vaccinated mice were reinfected with BCG, host resistance in spleen and liver was rapidly augmented to the accompaniment of striking changes in the morphology and microbicidal activity of the peritoneal macrophages. These changes occurred most rapidly in mice with a high level of delayed hypersensitivity at the time of reinfection.
TL;DR: The glomerular filtration of hemoglobin (α2β2) was studied under conditions in which its dissociation into αβ dimers was experimentally altered and indicated that under physiological conditions, BME hemoglobin had impaired subunit dissociation.
Abstract: The glomerular filtration of hemoglobin (alpha(2)beta(2)) was studied under conditions in which its dissociation into alphabeta dimers was experimentally altered. Rats receiving hemoglobin treated with the sulfhydryl reagent bis(N-maleimidomethyl) ether (BME) showed a much lower renal excretion and prolonged plasma survival as compared with animals injected with untreated hemoglobin. Plasma disappearance was also prolonged in dogs receiving BME hemoglobin. Gel filtration data indicated that under physiological conditions, BME hemoglobin had impaired subunit dissociation. In addition, BME hemoglobin showed a very high oxygen affinity and a decreased rate of auto-oxidation. Glomerular filtration was enhanced under conditions which favor the dissociation of hemoglobin into dimers. Cat hemoglobin, which forms subunits much more extensively than canine hemoglobin, was excreted more readily by the rat kidney. The renal uptake of (59)Fe hemoglobin injected intra-arterially into rabbits varied inversely with the concentration of the injected dose.
TL;DR: The pathogenesis of the glomerulonephritis of Aleutian disease is apparently related to formation of viral antigen-antibody-complement complexes which lodge in glomerular capillaries.
Abstract: Mink inoculated with 1 x 10(5)ID(50) of Aleutian disease virus revealed very high virus titers in the tissues 8-18 days later. The highest virus titers observed were 5 x 10(8)ID(50) per g of spleen and 1 x 10(9)ID(50) per g of liver 10 days after inoculation. Concomitant with the increase in infectious virus titers, viral antigen(s) was found in the cytoplasm of macrophages in the spleen and lymph nodes and in Kupffer cells in the liver. Antiviral antibody was assayed by indirect immunofluorescence, using sections of infected liver as the source of antigen. A few mink infected for 9 days and all those infected 10 days or more developed antibody to Aleutian disease virus antigen(s). By 60 days after infection, when hypergammaglobulinemia was marked, the mink had an exceptionally high mean antibody titer of 100,000. The pathogenesis of the glomerulonephritis of Aleutian disease is apparently related to formation of viral antigen-antibody-complement complexes which lodge in glomerular capillaries. No evidence was found that viral infection of the kidney took place, and no autoimmune responses were found. In this "slow-virus" disease the virus replicates rapidly and the morphologic and biochemical manifestations of disease are apparently due to the continuing interplay between a replicating antigen and the host immune response.
TL;DR: Ferritin-conjugated, type-specific antibodies localize on homologous M+ cells in a pattern suggestive of several M antigenic sites along the length of individual surface fimbria, suggesting the following hypothesis: M antigen is secreted by the cell, is partially excreted through the otherwise intact cell wall, and is bound by the wall so that M protein occupies a peripheral, exposed position on the surfaces of the streptococcal cell wall.
Abstract: The presence of M antigens on group A streptococci is associated with hairlike fimbriae that cover the surface of the streptococcal cell wall and are demonstrable by electron microscopy. These fimbriae also may be associated with R antigen. Like M protein, the surface fimbriae are destroyed by trypsin treatment and reappear when "trypsinized" streptococci are reincubated in fresh, trypsin-free broth.
Ferritin-conjugated, type-specific antibodies localize on homologous M+ cells in a pattern suggestive of several M antigenic sites along the length of individual surface fimbria. The M-associated fimbriae remain on the residual cell wall after removal of the bulk of group-specific polysaccharide through nitrous acid extraction. This suggests attachment of the fimbriae to the mucopeptide and minor polysaccharide components remaining in the nitrous acid-extracted wall.
The pattern of localization of ferritin-conjugated antibodies on homologous streptococci before and after trypsin exposure and upon reincubation of the trypsinized cells in fresh medium suggests the following hypothesis: M antigen is secreted by the cell, is partially excreted through the otherwise intact cell wall, and is bound by the wall so that M protein occupies a peripheral, exposed position on the surfaces of the streptococcal cell wall.
TL;DR: If the progeny of a single, genetically programmed chondrocyte may or may not synthesize chondroitin sulfate, then extragenic sites in the cytoplasm or cell surface must influence the decision as to which cluster of "luxur" molecules the cell will synthesize.
Abstract: A single, functional, mitotically quiescent chondrocyte may be induced to reenter the mitotic cyde, and produce a progeny of over 1011 cells. Sessile, adherent, polygonal cells deposit matrix, whereas amoeboid, dispersed, flattened fibroblastic cells do not. The prior synthetic history of a cell is of greater importance in determining whether the characteristic chondrogenic phenotype will be expressed, rather than growth in "permissive" or "nonpermissive" medium. Clonal conditions select for stem-like cells, some of whose progeny may become polygonal chondrocytes. The retention of the characteristic chondrogenic phenotype in vitro is favored by pruning the dedifferentiated chondrocytes which arise in these cultures. Dedifferentiated chondrocytes interfere with the deposition and synthesis of chondroitin sulfate by neighboring functional chondrocytes. Possible mechanisms are proposed to explain this type of cell-cell or cell exudate interference. If the progeny of a single, genetically programmed chondrocyte may or may not synthesize chondroitin sulfate, then extragenic sites in the cytoplasm or cell surface must influence the decision as to which cluster of "luxur" molecules the cell will synthesize.
TL;DR: A heat-labile, dialyzable serum cofactor which enhances C3 peptidase activity enhanced the phagocytosis of pneumococci prepared with purified complement components.
Abstract: The role of serum factors in the phagocytosis of pneumococci was studied employing a spectrophotometric assay which measures reduced nitro blue tetrazolium (NBT) dye. Dye reduction occurs within the phagocyte shortly after bacterial ingestion as measured by the phagocytic index technique and by the uptake of (125)I-pneumococci. Bacteria prepared with gammaG antibody were not phagocytosed unless a small volume of fresh normal serum was added. Using fresh sera deficient in single complement components, it was demonstrated that the first four components are necessary for optimal bacterial phagocytosis. When highly purified complement components were added to the antibody-coated pneumococci, enhancement of phagocytosis was achieved only with the sequential addition of C1, C4, C2, and C3. Evidence has been presented that human C3 bound to an immune complex exhibits peptidase activity and that this activity is essential for phagocytosis. A heat-labile, dialyzable serum cofactor which enhances C3 peptidase activity enhanced the phagocytosis of pneumococci prepared with purified complement components. A second phagocytosis-promoting cofactor, which is not a complement component, was found to be a heat-labile, 5-6S, beta pseudoglobulin. This protein may stabilize C3 peptidase activity or inhibit enzymatic inactivation of C3.
TL;DR: The distribution of large dividing lymph node or thoracic duct lymph cells, labeled in vitro with 3H-thymidine, was studied in syngeneic recipient rats after intravenous injection and found that the labeled cells rapidly "homed" to lymphoid tissue and recirculated in the recipient, in a fashion resembling that of small lymphocytes.
Abstract: The distribution of large dividing lymph node or thoracic duct lymph cells, labeled in vitro with (3)H-thymidine, was studied in syngeneic recipient rats after intravenous injection. In most experiments the donor rats had been immunized with Bacillus pertussis 4 days earlier, but in some instances cells from nonimmunized donors were used. In smears, the labeled donor cells had the appearance of large lymphocytes or large pyroninophilic cells. By electronmicroscopy, the majority of labeled donor cells were seen to have only scanty endoplasmic reticulum. It was found that the labeled cells rapidly "homed" to lymphoid tissue and recirculated in the recipient, in a fashion resembling that of small lymphocytes. However, the distribution of labeled cells was found to depend upon the source of the donor cells. Cells from mesenteric lymph nodes or thoracic duct lymph showed a marked preferential accumulation in lymphoid tissue within or adjacent to the intestine, whereas cells from peripheral nodes accumulated preferentially in peripheral lymph nodes. Cells from any of these sources showed an equal tendency to accumulate in the white pulp of the spleen. Suspensions of small lymphocytes, labeled in vitro with (3)H-uridine, did not display a similar tendency to localize preferentially in lymphoid tissue in certain regions. It was also found that large dividing lymph node cells from donors immunized with an antigen (2,4-dinitrophenyl-bovine gamma globulin (DNP-BGG) or B. pertussis) showed a greater tendency to accumulate in a recipient lymph node containing that antigen than in the contralateral node. It was not determined whether the selective accumulation of large dividing lymphoid cells from different sources in lymphoid tissue of different regions in recipients was due to an antigen recognition mechansim or was the result of two different populations of cells with different "homing" mechanisms.
TL;DR: The role of the gut as a site of antibody synthesis, as well as its selective commitment to the production of antibodies of the IgA class, is illustrated by germfree C3H mice immunized with horse spleen ferritin.
Abstract: In adult germfree C3H mice immunized with horse spleen ferritin, either subcutaneously or intraperitoneally, plasma cells containing specific antibodies were found in lymph nodes and spleen and, in smaller numbers, also in the lamina propria of the intestine. In extraintestinal sites, these antiferritin-containing plasma cells were mainly of the IgM class after a single stimulation, and of the IgG1 class after repeated stimulation. In the intestine, all the anti-ferritin-containing cells appeared to be of the IgA class. Circulating antibodies, after repeated stimulation, were for the major part IgG1 and IgG2. In germfree mice given ferritin in their drinking water, antiferritin-containing cells were abundant in the intestinal mucosa, much less numerous in the mesenteric lymph nodes, and extremely scarce in other lymphoid tissues. All these cells, whatever their location, appeared to belong exclusively to the IgA class. Similarly, all the circulating antibody in these animals was found to be IgA. These findings illustrate the role of the gut as a site of antibody synthesis, as well as its selective commitment to the production of antibodies of the IgA class.
TL;DR: Hemagglutinating and bactericidal activity developed in the sera of all individuals with the exception of two recruits injected with A polysaccharide, and during the 6 wk period of observation, the proportion of unvaccinated recruits who acquired group C meningococci in the three companies studied was 38, 42, and 69 per cent.
Abstract: Purified meningococcal polysaccharides were administered to army recruits. No adverse reactions were observed in 145 men who received group C polysaccharide, and in 53 men who were injected with group A polysaccharide. Hemagglutinating and bactericidal activity developed in the sera of all individuals with the exception of two recruits injected with A polysaccharide. During the 6 wk period of observation, the proportion of unvaccinated recruits who acquired group C meningococci in the three companies studied was 38, 42, and 69 per cent. A significantly lower proportion of the individuals vaccinated with group C polysaccharide acquired group C meningococci; 4.6, 24, and 31 per cent respectively.
TL;DR: A better definition of cell surface structure, gained from studies such as this, is necessary for further inquiry into how the cell surface is assembled, and into selective gene action in relation to cellular differentiation.
Abstract: The representation of mouse alloantigens belonging to three systems, H-2, θ and TL, on the surface of cells from thymus, spleen, lymph nodes, and peritoneal cavity, was studied by electron microscopy with ferritin-labeled antibody. As expected from earlier serological data, TL was confined to thymocytes, θ was found on thymocytes and lymphocytes, and H-2 occurred to some extent on all cell types observed. On reticular cells, lymphocytes, plasma cells, and eosinophils, the majority of the cell surface was occupied by H-2; thymocytes had considerably less H-2, and erythrocytes and peritoneal macrophages least of all. In every instance the representation of antigen was discontinuous, the fraction of the cell surface covered being characteristic both of the antigen and of the type of cell. H-2 and θ provide a striking example of this; H-2 is present in far higher amounts on lymphocytes than on thymocytes, whereas the converse is true of θ. Within areas positive for H-2 or θ, protuberances of the surface membrane were often antigen-negative.
A better definition of cell surface structure, gained from studies such as this, is necessary for further inquiry into how the cell surface is assembled, and into selective gene action in relation to cellular differentiation.
TL;DR: The exposure of cultivated mouse macrophages to sucrose leads to the formation of large phase- and electron-lucent, acid phosphatase-positive vacuoles in the perinuclear region, and the uptake of sucrose by pinocytosis and its subsequent segregation and storage in secondary lysosomes are suggested.
Abstract: The exposure of cultivated mouse macrophages to sucrose (0.009–0.03 M) leads to the formation of large phase- and electron-lucent, acid phosphatase-positive vacuoles in the perinuclear region. The vacuolization process and the uptake of sucrose-14C is blocked by inhibitors of pinocytosis and stimulated by calf serum in the medium. These results suggest the uptake of sucrose by pinocytosis and its subsequent segregation and storage in secondary lysosomes. The addition of sucrose also increases the total content of three macrophage lysosomal hydrolases. The addition of invertase to the environment of sucrose-laden macrophages leads to the prompt shrinkage of the sucrose-containing lysosomes. This is accompanied by the intracellular hydrolysis of sucrose to fructose and glucose residues which are promptly excreted into the medium. The uptake of invertase, as indicated by the shrinkage of sucrose-containing vacuoles, is blocked by inhibitors of pinocytosis. No effect was noted when invertase was added to macrophages laden with Ficoll, a polysucrose which is not hydrolyzed by the enzyme. The influence of other carbohydrates was then investigated. Monosaccharides with molecular weights up to 220 did not produce vacuolization. However, a certain number of di-, tri-, and tetrasaccharides produced vacuolization identical with that of sucrose. Each of the disaccharides which produced vacuolization was resistant to the complement of macrophage hexosidases, whereas those that were ineffective were degraded by either macrophage or serum enzymes. The addition of β-glucosidase to cellobiose-laden macrophages resulted in the shrinkage of vacuoles but did not alter the vacuoles of sucrose containing cells. The ability of small, neutral carbohydrates to produce lysosomal swelling is dependent upon both molecular weight and their resistance to lysosomal hydrolases.
TL;DR: Mouse spleen cells were found to associate in cell clusters during the primary immune response to sheep erythrocytes in vitro, and the integrity of cell clusters was required for the proliferation of antibody-forming cells, and prevention of clusters by mechanical means or by excess antibody blocked the immune response.
Abstract: Mouse spleen cells were found to associate in cell clusters during the primary immune response to sheep erythrocytes in vitro. About 10% of the cell clusters had the following unique properties; (a) they contained most, if not all, antibody-forming cells, (b) they contained only cells forming antibody to one antigen when cell cultures were immunized with two antigens, (c) the cells in clusters reaggregated specifically after dispersion, and (d) the specific reaggregation of clusters appeared to be blocked by antibody to the antigen. The integrity of cell clusters was required for the proliferation of antibody-forming cells, and prevention of clustering by mechanical means or by excess antibody blocked the immune response. Antibody and antigenic determinants on the surfaces of cells probably provide the basis for interaction. The unique microenvironment of cell clusters was essential for the primary immune response in vitro.
TL;DR: The collective findings implicate murine leukemia-like virus in the etiology of autoimmune hemolytic disease and membranous glomerulonephritis, as well as malignant lymphoma, of NZB mice and suggest that virus-specified cell-surface and soluble antigen is a factor in the immunopathogenesis of the renal disease and possibly also the autoimmune hemologic disease.
Abstract: Further evidence implicating murine leukemia-like virus in the disorders of NZB mice was afforded by a study of antigens associated with murine leukemia virus (MuLV). MuLV group antigens were prevalent in extracts of spleen, kidney, and, to a lesser extent, thymus throughout a substantial portion of the life span of NZB mice as well as in extracts of lymphomas and sarcomas indigenous to the strain. G (Gross) soluble antigen, type-specific antigen, was first detected in plasma of untreated NZB mice at 3 months of age. G soluble antigen production increased thereafter in line with age, with 50% of reactions becoming positive at 5.3 months and 100% at 7 to 9 months. From months 3 to 9, the time-response curve for positive conversion of direct antiglobulin (Coombs) tests in untreated NZB mice corresponded closely to that for G soluble antigen production. Beyond the 9th month, G soluble antigen underwent elimination from the plasma of NZB mice, with positive reactions reduced to 50% at 13.3 months and to 0% at 18 months. G natural antibody was first detected in the serum of NZB mice at about 10 months of age and increased thereafter in line with age. The curves for G antibody production and G soluble antigen elimination bore a reciprocal relation to each other with crossover at 50% response occurring at 13.3 months. Significant proteinuria, a functional manifestation of membranous glomerulonephritis, became increasingly prevalent in female NZB mice as G soluble antigen was eliminated from plasma. Cumulative mortality of female NZB mice, mainly attributable to renal glomerular disease, increased in phase with G antibody production. MuLV group antigens were identified in the glomerular lesions by the immunofluorescence method. Positive conversion of direct antiglobulin tests was significantly delayed by vaccinating baby NZB mice with formaldehyde-inactivated cell-free filtrates of older NZB mouse spleens. The plasmas of vaccinated NZB mice with negative direct antiglobulin reactions at 4 to 7 months were likewise negative when tested for G soluble antigen. The 50% response time for G antibody production in the vaccinated NZB mice occurred at 7.3 months, that is, 6 months earlier than in untreated NZB mice. The collective findings implicate murine leukemia-like virus in the etiology of autoimmune hemolytic disease and membranous glomerulonephritis, as well as malignant lymphoma, of NZB mice and suggest that virus-specified cell-surface and soluble antigen is a factor in the immunopathogenesis of the renal disease and possibly also the autoimmune hemolytic disease.