Showing papers in "Immunology in 1980"

Inhibition of phagocytosis by high molecular weight hyaluronate.

Abstract: The effect of sodium hyaluronate on phagocytosis was studied using a sensitive polystyrene latex sphere assay in mouse peritoneal macrophage monolayers. Viscous solutions of high molecular weight hyaluronate (4.6 X 10(5)--2.8 X 10(6)) caused a dose-dependent inhibition of phagocytosis, but low molecular weight hyaluronate (9.0 X 10(4)) was not inhibitory at equivalent viscosity. The inhibitory effect of high molecular weight hyaluronate did not appear to be mediated by the polyanionic charge of the molecule since sulphated glycosaminoglycans with greater charge density (heparin and chondroitin sulphate) were ineffective. In addition, competitive inhibition studies indicated that a direct effect on possible cell surface membrane receptors was unlikely. Instead, physical factors such as steric hindrance by the continuous polymeric network, were considered of more importance. Alternatively, the hydrophilic polysaccharide may have inhibited phagocytosis by providing an unsuitable surface for adhesive contact between the latex beads and the cell surface.

The measurement of opsonic and phagocytic function by Luminol-dependent chemiluminescence.

Abstract: Luminol-dependent chemiluminescence produced by peripheral blood phagocytic cells was measured using a light detecting instrument, the Luminometer 1250 (LKB Wallac). Although less sensitive than liquid scintillation counters, the Luminometer can measure chemiluminescence effectively and detect experimentally induced and clinical variations using small numbers of cells. It is small, inexpensive, simple to use and allows temperature within the reaction vial to be controlled accurately. Light emission can be recorded either graphically or by an intergrated digital printout. Luminol-dependent chemiluminescence is influenced by the presence of contaminating red blood cells and by composition of the medium, particularly presence of phenol red. HEPES buffer and foetal calf serum. Whereas clinical comparisons of opsonic activity are easily performed, comparisons of cellular activity require a high and uniform standard of cell preparation, characterization and maintenance.

Separation of human eosinophils in density gradients of polyvinylpyrrolidone-coated silica gel (Percoll).

Abstract: A method for isolation of eosinophils from human peripheral blood using isosmolar solutions of polyvinylpyrrolidone-coated silica gel (Percoll) is described. The purity ranged from 86 to 99% eosinophils in the final preparation and the recovery was 38-56%. The separation technique did not affect the viability or the metabolic capacities of the cells.

The immune system of cyprinid fish. Kinetics and temperature dependence of antibody-producing cells in carp (Cyprinus carpio).

Abstract: After immunization of carp with sheep red blood cells, the spleen accounts for only 5% of the total number of plaque-forming cells (PFC). In addition, thymus, peripheral blood and heart contained low numbers of PFC (< 0.5, 1 and 0.5%, respectively). Pronephros and mesonephros were the major antibody-forming organs (53 and 40% of total PFC, respectively). The temperature dependence of the antibody-forming cell response in spleen, pronephros and mesonephros as studied in animals kept at 12-24 degrees. Lowering temperatures induced a delay in the peak of the primary response but had no effect on the magnitude of the response. The temperature-peak day relationship indicated that there are steps in the primary immune response of carp differing in temperature sensitivity. The anamnestic character of the secondary response was clearly demonstrated at 24 and 20 degrees but lost at 18 degrees.

Modulation of human neutrophil function by monohydroxy-eicosatetraenoic acids.

Abstract: The generation from arachidonic acid and purification of large quantities of a series of monohydroxy-eicosatetraenoic acids (HETEs) which differed only in the position of the hydroxyl group permitted an in vitro analysis of the relative effects of the HETEs on a variety of human neutrophil functions. All of the HETEs elicited maximal neutrophil chemotactic responses of comparable magnitude, but the chemotactic potencies exhibited a distinct rank order with 5-HETE greater than 8-HETE:9-HETE (85:15, w:w) greater than 11-HETE=12-L-HETE. Peak chemotactic responses were achieved at concentrations of 1 microgram/ml for 5-HETE, 5 microgram/ml for 8-HETE:9-HETE and 10 microgram/ml for 11-HETE and 12-L-HETE. In the absence of a concentration gradient, the HETEs were similar in potency with respect to the stimulation of neutrophil chemokinesis and the enhancement of the expression of neutrophil C3b receptors. At optimally chemotactic and chemokinetic concentrations, none of the HETEs stimulated the generation of superoxide by neutrophils, altered the expression of neutrophil IgG-Fc receptors, or evoked the release of lysosomal enzymes. Methyl esterification of 5-HETE and 12-L-HETE reduced the chemotactic activity to less than 12% of that of the parent compound. The HETE methyl esters competitively inhibited the chemotactic activity of the homologous free acids by approximately 50% at equimolar concentrations, without inhibiting the chemotactic activity of formyl-methionyl peptides or of chemotactic fragments of the fifth component of complement (C5fr). The stimulus specificity of the competitive inhibition of chemotaxis by HETE methyl esters and the functional selectivity of the HETEs as compared to the formyl-methionyl peptides and C5fr, which stimulate neutrophil oxidative metabolism and lysosomal enzyme release, suggest that HETEs activate human neutrophils by a unique mechanism.

Quantitative immunohistochemistry of immunoglobulin- and J-chain-producing cells in human parotid and submandibular salivary glands.

Abstract: Ig-producing cells were quantified by paired immunohistochemical staining in saline-extracted and paraffin-embedded normal tissue specimens from human parotid (ten) and submandibular (seven) salivary glands. The density of such cells (number/mm2 of 6 micron thick tissue section) was significantly higher in the submandibular than in the parotid gland (P less than 0.005), but the Ig-class distribution was fairly similar. The mean percentage class ratios for IgG, IgA, IgM and IgD cells in the parotid were 4.5:86.5:5.9:3.1, and in the submandibular gland 3.7:86.9:7.9:1.6. In the parotid gland of a patient with selective IgA deficiency the same class ratios were 27:0:20:53. Thus, the IgA cells were especially replaced by IgD cells. In normal glands most of the IgA (80-93%), IgM (99-100%) and IgD cells (81-95%) were J-chain-positive; this was likewise true for a substantial proportion of the IgG cells (32-46%). Of additional interest was the finding that in the IgA-deficient parotid gland, 99% of the numerous IgD cells and 86% of the increased number of IgG cells contained cytoplasmic J chain. IgE-producing cells were virtually absent from the IgA-deficient as well as from the normal salivary glands.

A role for endogenous mono-hydroxy-eicosatetraenoic acids (HETEs) in the regulation of human neutrophil migration.

Abstract: The possibility that endogenous monohydroxy-eicosatetraenoic acids (HETEs) derived from the lipoxygenation of arachidonic acid might serve a role in human neutrophil migration was examined by studying the effects of depletion of the intracellular HETEs on random migration and chemotaxis. The intracellular contents of approximately 2000 ng of 11-HETE and 500 ng of 5-HETE per 10(8) neutrophils are distributed preferentially in the cellular membranes and are increased by specific chemotactic factors. The depletion of intracellular HETEs that resulted from pre-incubating, washing and resuspending neutrophils in 3-20 microM 5,8,11,14-eicosatetraynoic acid (TYA), an inhibitor of lipoxygenase and cyclooxygenase activity, or in 5-10 microM nordihydroguaiaretic acid (NDGA), a selective inhibitor of lipoxygenase activity, was associated with suppression of neutrophil random migration and chemotaxis to several stimuli without evidence of cytotoxicity. Maximal suppression of migration was achieved by a 30-60 min preincubation with the inhibitors, a time-course analogous to that required for optimal depletion of the endogenous HETEs. In contrast, inhibitors of cyclooxygenase activity enhanced random migration and, to a lesser extent, chemotaxis. The inhibition of migration achieved by pre-incubating and maintaining the neutrophils in TYA or NDGA was fully reversed either by washing and resuspending the neutrophils in buffer or by the addition of purified neutrophil 5-HETE in quantities as small as 20 ng/2 x 10(6) neutrophils for random migration and 0.8 ng/2 x 10(6) neutrophils for chemotaxis, while the addition of 11-HETE was less effective. The relationship of the intracellular concentrations of endogenous HETEs to neutrophil migration is consistent with a potential role of the HETEs as cellular mediators.

Anaphylactic release of intestinal goblet cell mucus.

Abstract: The effect of intestinal anaphylaxis on goblet cell mucus release was tested in rats immunized with small doses of egg albumin and alum and challenged intraduodenally with antigen The alteration in vascular and mucosal permeability which accompanies intestinal anaphylaxis was reflected by increased retention of 125I-labelled rat serum albumin in gut wall segments and increased amounts of protein-bound radioactivity in the intestinal secretion from the segments Intestinal goblet cell mucus was labelled in vivo with 35S Infusion of antigen, into the duodenum of actively immunized rats led to the appearance of 35S-labelled high molecular weight glycoprotein, presumably of goblet cell origin, in the intestinal secretions Goblet cell mucus release was dependent on the dose of antigen infused, was antigen-specific and was inhibited by pretreatment of rats with cyproheptidine Enhanced release of goblet cell mucus was observed in normal rats prepared by intravenous injection of rat antiserum rich in IgE anti-egg albumin antibodies and challenged by intraduodenal infusion of antigen Prior heating of the antiserum inhibited passive transfer of the reaction; this finding is consistent with the heat lability of IgE antibodies The latter class of antibodies are presumed to be responsible for intestinal anaphylaxis and its associated mucus release in the model system examined

Differences in inhibition of the growth of commensal and enteropathogenic strains of Escherichia coli by lactotransferrin and secretory immunoglobulin A isolated from human milk.

Abstract: Immunoglobulins from bovine and human colostrum and milk and lactotransferrin (LTF) from human milk were investigated for bacteriostatic activity against Escherichia coli growing in a tissue culture medium When tested separately, LTF or secretory immunoglobulin A (sIgA) from pooled human milk showed only slight bacteriostatic activity against human commensal or enteropathogenic strains of E coli Together, they had a considerable bacteriostatic effect, but only against strains of enteropathogenic serotype This activity of the sIgA from pooled human milk was consistent for all enteropathogenic serotypes tested, but sIgA isolated from individual milk samples was inactive against some serotypes, and this specificity was associated with antibody to the O antigens The activity of the sIgA was stable to heat at 56 degrees for 2 h but was lost progressively on heating at 65 degrees for 10 min or longer Bovine colostral IgGl was without bacteriostatic effect alone Together with LTF, it was active against a strain pathogenic to calves but not against human enteropathogenic strains Tests on rabbit antisera raised against commensal enteropathogenic strains of E coli showed that for the enteropathogens the bacteriostatic activity (in association with LTF) was high and was specific for the serotype of the eliciting strain, but bacteriostatic activity was low or absent in the antisera to commensal strains in spite of the presence of high titres of agglutinating antibodies to these strains

Histamine regulates lymphocyte mitogenic responses through activation of specific H1 and H2 histamine receptors.

Abstract: In previous studies we have reported that patients with mild atopic eczema have enhanced lymphocyte mitogenesis while those with severe disease have markedly suppressed responses. Similarly, histamine in low concentrations enhanced mitogenesis while higher levels inhibit mitogen stimulated thymidine uptake. In the present study, we investigated the kinetics of this response and the interaction of histamine with its cell-surface receptors on lymphocytes. Histamine (10(-3) M) markedly inhibited [3H]-thymidine incorporation to 27% of control levels when added at the beginning of a 72 h culture period. When added after 24 and 48 h of culture, however, the suppression was much less (62 and 88% of control). Lymphocyte cultures pulsed for 1 h with histamine, washed free of the agent and then cultured with mitogen also showed marked suppression of [3H]-thymidine uptake. The kinetics of the response suggest that histamine acts to inhibit initial processing or recruitment steps in the mitogenic assay. Cimetidine, an H2-receptor blocking agent, prevented the suppressive effect of high levels of histamine while diphenhydramine, an H1 blocker, abolished the enhancement observed with low levels. Pre-incubation of mononuclear cell suspensions, which has been shown to decrease suppressor activity, resulted in a decreased response to added histamine. This change in histamine responsiveness was associated with an alteration in H1:H2 histamine binding as determined with a radiolabelled ligand-binding assay. Histamine suppression of mitogenesis was associated with an increase in cellular cAMP levels while enhancement was accompanied by a small increase in cGMP. These data suggest that lymphocyte function may be regulated, in part, by histamine receptor bearing cells with H1 stimulation having a role in enhancement of mitogenesis and H2 stimulation resulting in normal suppressor activity.

Platelet-activating factor in anaphylaxis and phagocytosis. I. Release from human peripheral polymorphonuclears and monocytes during the stimulation by ionophore A23187 and phagocytosis but not from degranulating basophils.

Abstract: Platelet-activating factor (PAF) is a mediator of a anaphylaxis found initially in basophils and later in mouse and rat macrophages. The purpose of this paper was to determine the cellular origin of PAF released from human leucocytes and to establish if phagocytosis is a more important stimulus for PAF release than anaphylactic reactions. Phagocytic leucocytes (monocytes and PMNs) released PAF, physicochemically analogous to the PAF obtained by anaphylactic reactions in rabbits when challenged with zymosan, zymosan coated with complement, immune complexes, immunoglobulin aggregates or calcium ionophore A23187. Basophils failed to release PAF by anti-human IgE antibody, although positive degranulation and histamine liberaton were found. Pre-incubation of phagocytosing leucocytes with cytochalasin B or colchicine produced a diminution of PAF release, whereas beta-glucuronidase liberation was increased. The addition of carboxypeptidase B did not significantly modify PAF or beta-glucuronidase release. These data indicate that PAF obtained from preparations of human leucocytes comes from monocytes and polymorphonuclears; human basophils do not liberate measurable quantities of PAF, either by anaphylactic stimulus or by neutrophil cationic proteins; liberation of PAF and lysosomal content follow different mechanisms as they have different kinetics and are modified in an opposite way by drugs acting on the cytoskeleton.

Three rat monoclonal antibodies to human C3.

Abstract: Three monoclonal antibodies to human C3 have been obtained from a fusion of the rat myeloma line Y3 Ag 1.2.3. with spleen cells from rats immunized against C3. One, from clone 4, reacts with an antigenic determinant in C3c showing the expected reactivity of the 'C' antigen of C3. The specificity of the other two monoclonal antibodies correspond less clearly with known C3 antigens. By agglutination analysis of complement coated cells the determinant reacting with clone 3 is present in C3d while that for clone 9 appears as a neoantigen on C3bi. In both cases the co-precipitation results are anomalous and more direct studies are needed to define the exact specificity. The possibility that internal sequence duplications in C3 may explain some anomalies is discussed. None of the monoclonal antibodies significantly inhibit C3 functions. The monoclonal antibodies have been found to have unusual properties in co-precipitation assays being able to diffuse through a precipitation line with which they react to react with a further line. One antibody is also able to react strongly with the anodal half of what appears as a single line with a polyclonal antiserum.

Target-effector cell interaction in the natural killer cell system. V. Energy requirements, membrane integrity, and the possible involvement of lysosomal enzymes.

Abstract: Various inhibitors were used to study further the mechanism of natural killing and to compare it to lympholysis by cytotoxic T lymphocytes (CTL). The respiratory inhibitors DNP and NaN3 or low temperatures (0 degrees) blocked the cell contact phase of target-effector interaction in the CTL system but not the NK system. The lytic stage was also inhibited by the glycolytic inhibitors, iodoacetate and NaF, in the NK system as previously shown in the CTL system. Dimethylsulphoxide, a dipolar solvent, and cytochalasin B, a microtubule disruptor, inhibited NK target binding. Pre-treatment of Nk cells with glutaraldehyde, a protein cross-linking agent, completely prevented lysis, but not the formation of target-effector conjugates. The lytic phase of NK lysis was inhibited by chloroquine which also inhibited lysosomal enzyme function. Lysosome defective, beige mutant mice were also totally deficient in NK lytic function and this defect could not be restored with cGMP. T-cell and macrophage mediated cytolysis was previously shown to be relatively normal in beige mice. These results suggest that (i) the mechanism of NK cytolysis is a complex, multistep process, and (ii) this process is fundamentally different from that occurring in CTL. A 'stimulus-secretion' model of NK cytolysis is presented in which it is postulated that lysosomal enzymes may be the lytic molecules.

Immunological clearance of 75Se-labelled Trypanosoma brucei in mice. II. Mechanisms in immune animals.

Abstract: Using trypanosomes labelled with [75Se]-methionine a series of experiments was conducted to investigate the respective roles of antibody, macrophage activtion and complement in the removal of trypanosomes from the circulation of immune mice It was found that clearance in such animals is largely accomplished by antibody-mediated hepatic phagocytosis, which, at least in passively immunized animals, is dependent on opsonization involving C3 No evidence was found to suggest that intravascular lysis or activated macrophages are involved in immune clearance

A mechanism to account for mouse strain variation in resistance to the larval cestode Taenia taeniaeformis.

Abstract: Mice of various inbred strains differ markedly in resistance to first infection with Taenia taeniaeformis. Hypothymic nude mice of relatively resistant (e.g. BALB/c) and relatively susceptible (e.g. CBA/H) genotypes are highly susceptible but both can be protected against infection by injection of serum from infected mice. Using differential pH elution of "immune serum" from protein A-Sepharose, evidence was obtained that a combination of the pH 6 eluate (enriched for IgG1 molecules) plus the pH 3 or 4 eluate (enriched for IgG2 molecules) was more effective than either eluate alone at transferring protection to nude mice. By using whole serum transfer techniques, the rate of appearance of "host protective serum activity" (presumably antibody) was shown to be increased in genetically resistant versus susceptible mouse strains. It is suggested that, in relatively resistant mouse strains, host protective antibodies prejudice the establishment (or subsequent survival) of larvae prior to the full expression of protective mechanisms in the establishing larvae. In keeping with a host-protective effect of an accelerated immune response early in infection, a high dose challenge with eggs actually resulted in lower infection levels in genetically resistant mouse strains such as BALB/c and C57B1/6. The proposed mechanism of immunologically mediated, genetically based variation in susceptibility to T. taeniaeformis should not influence the effectiveness of a model vaccine against first infection in all strains of mice.

Induction of cytotoxic peritoneal exudate cells by T-cell immune adjuvants of the beta(1 leads to 3) glucan-type lentinan and its analogues.

Abstract: Eight distinct polysaccharides (PS) of beta(1 leads to 3) glucan type were tested for their capacity to render murine peritoneal exudate cells (PEC) cytotoxic. After intraperitoneal injection of lentinan, pachymaran and HE-pachyman 3 and 4 highly cytotoxic PEC were induced. Pachyman and HE-pachyman 1 and 2 were of moderate effect, whereas CM-pachymaran and HE-pachyman 3 and 4, highly cytotoxic PEC were induced. Pachyman and HE-pachymacrophages. The induction of PEC-dependent cytotoxicity exhibited a strict dose relationship. Optimal administration of PS resulted in the induction of cytotoxicity, which persisted for more than 25 days. Surprisingly, none of the PS tested was capable of rendering normal or thioglycollate-induced PEC cytoxic under in vitro conditions. It is suggested that the capacity of PS to render in vivo macrophages cytotoxic is related to the potency of these PS to activate the alternative pathway of complement system (APC) in so far as C3b may be the essential component required to render macrophages cytotoxic.

The in vivo division and death rates of Salmonella typhimurium in the spleens of naturally resistant and susceptible mice measured by the superinfecting phage technique of Meynell.

Abstract: Salmonella typhimurium appears to divide faster in the spleen of naturally susceptible BALB/c than in resistant (B10 x A/J)F1 mice. S. typhimurium M526 is an LT2 derivative lysogenic for a non-excluding P22 mutant which allows superinfection with a second, non-replicating, P22 phage so that the proportion of superinfected organisms halves at each division. The true in vivo division and death rates can be calculated from successive determinations of the proportion of superinfected organisms and the viable count. It was found that the division time was 2.86 h in BALB/c and 5.02 h in (B10 x A/J)F1; the death rate was low and actually greater in the susceptible BALB/c strain. These results suggest that the gene controlling in vivo salmonella net growth rate, which is very important in natural resistance to salmonella infection, acts very early by regulating the division rate, perhaps inside macrophages. The actual mechanism remains unknown.

Serological and immunochemical characterization of monoclonal antibodies to Toxoplasma gondii.

Abstract: The fusion of mouse NS-1 myeloma cells with spleen cells from mice chronically infected with Toxoplasma gondii resulted in eight clones of hybridomas producing monospecific antibodies against membrane or cytoplasmic antigens of Toxoplasma tachyzoites. One of the antibodies to a cytoplasmic determinant was an IgM; the others directed to membrane or cytoplasmic antigens belonged to the IgG2 or IgG3 isotypes. Antibodies of clones 1E11 (IgG3), 2G11, and 3E6 (IgG2) directed to membrane antigens, bound complement and were reactive in the complement-dependent cytotoxicity assay of Sabin-Feldman. These IgG2 antibodies were strongly agglutinating to parasites, whereas the IgG3 was relatively weak. Another IgG2 antibody (5B6), possibly recognizing a shared antigen of membrane and cytoplasm, exhibited a low titre in the cytotoxicity assay as well as in the agglutination assay. Two other antibodies to membrane antigens (2B7 and 2F8) as well as an antibody to a cytoplasmic antigen (3G3) did not bind complement and did not cause agglutination. The pattern of parasite staining produced by monoclonal antibodies to membrane antigens in an IFA test was different from that of polyvalent antisera. A strictly localized or 'beaded' staining was observed, as well as a smooth, rim fluorescence. Toxoplasma tachyzoites were surface radio-iodinated and the solubilized membrane proteins were immunoprecipitated with monoclonal antibodies and analysed by two-dimensional polyacrylamide gel electrophoresis. Two independently arising monoclonal antibodies to membrane antigens (2G11 and 3E6) consistently precipitated both the solubilized 35,000 and 14,000 mol. wt proteins, while 1E11 precipitated the 27,000 mol. wt protein.

Growth and differentiation in vitro of mast cells from mesenteric lymph nodes of Nippostrongylus brasiliensis-infected rats.

Abstract: Intestinal mastocytosis begins to develop in rats, depending on the strain, at 14 (outbred Sprague-Dawley, SD) or 16 (inbred Lewis, L) days after infection with the nematode Nippostrongylus brasiliensis (Nippo) We have investigated in vitro mastopoiesis from mesenteric lymph node (MLN) cells cultured at various intervals post-infection, using a modified Marbrook liquid system Greater increases in mast cells (MC) were observed in cultures of SD-MLN removed on day 14 after Nippo infection (IMLN-14) than from MLN removed from uninfected animals (NMLN): seven- to twenty-fold versus up to two-fold at 2 weeks and forty- to two hundred-fold versus up to twenty-fold at 4 weeks, respectively (P < 0002) In contrast, similar differential increases in MC and histamine compared to uninfected controls, were demonstrated in 2 week cultures of MLN from L strain rats removed 17 (IMLN-17) and 20 (IMLN-20) but not 14 days after Nippo infection (P < 0001) the presence of phytohaemagglutinin (PHA) in vitro was associated with enhanced MC differentiation from both IMLN-17 and IMLN-20, while worm antigen (Ag) stimulated mastopoiesis from IMLN-17, but suppressed the response from IMLN-20 (P < 002) Conditioned media (CM) prepared from unstimulated or PHA-stimulated IMLN-32 (ie removed 32 days after Nippo infection) caused significant mastopoiesis from NMLN in vitro when compared to no CM or Ag-stimulated CM (P < 001) Either MC precursors or cells which help MC differentiation exist in increased numbers in MLN of Nippo-infected rats Mitogenic or antigenic stimulation modulates in vitro mastopoiesis, either directly or through soluble factors derivable from MLN cells These in vitro methods can be utilized to understand further mechanisms of intestinal mastocytosis in the rat

Retinoids as regulators of macrophage function.

Abstract: Retinol (vitamin A) and retinoic acid, at concentrations in the physiological range, were found to exert potent regulatory effects on the function of macrophages; suppressing the expression of Fc receptors and the subsequent phagocytosis of opsonized cells but enhancing production of the tumouricidal enzyme arginase. Another dietary essential lipid-soluble molecule, arachidonic acid, from which a number of active molecules known to regulate cellular function are derived, had no effect on macrophage receptor expression or phagocytosis.

Increased biosynthesis of complement components by cultured monocytes, synovial fluid macrophages and skynovial membrane cells from patients with rheumatoid arthritis.

Abstract: Monocytes, synovial fluid (SF) and synovial membrane (SM) macrophages from patients with rheumatoid arthritis (RA) were maintained in short-term tissue culture for up to 10 days, and the synthesis of C4, C2, C3, C5, factor B(B), D, properdin (P), C3b inactivator (C3bINA) and beta 1H globulin studied. Functionally active C2, B, D, P, C3bINA and beta 1H were synthesized by the cells in each type of culture. C4, C3 and C5 could be detected, but were functionally inactive. RA monocytes synthesized more C2 than monocytes from patients with degenerative joint disease (DJD) (P < 0.001). Similar studies revealed that SF macrophages synthesized more C3 than SM macrophages (P < 0.001) which in turn produced more C2 than monocytes (P < 0.001). Other experiments showed that SF macrophages synthesized more of each component than the other cell types. SM macrophages made more C2 than B than RA and DJD monocytes, but synthesized only small quantities of P, D and beta 1H. RA monocytes synthesized more of each component than DJD monocytes. The results of these studies show that (1) in RA, complement components can be synthesized locally in the inflamed joints, and (2) local factors in the joints probably stimulate complement synthesis.

Distribution of immunogenic cells after painting with the contact sensitizers fluorescein isothiocyanate and oxazolone. Different sensitizers form immunogenic complexes with different cell populations.

Abstract: The distribution of fluorescent cells in the draining lymph nodes of mice painted with the contact sensitizing agent fluorescein isothiocyanate (FITC) was investigated using a fluorescence-activated cell sorter Up to 30% of the cells were fluorescent after 18 h and this decreased thereafter becoming undetectable after 4-5 days Most of the fluorescent cells were morphologically lymphocytes, theta - ve and adherent to nylon wool Immunogenicity of these cells was tested by injecting them into the footpads of normal mice and measuring contact sensitivity after 6 days This was restricted to large cells which represented less than 5% of the white cell population and nearly all of which became fluorescent after skin painting The large fluorescent cells were a mixture of monocytes and lymphocytes Most of the lymphocytes had surface immunoglobulin The immunogenicity was reduced by nylon filtration but was not affected by silica and anti-theta These results showed that the immunogenicity is not associated with T cells In contrast, similar immunogenic activity in the draining lymph nodes of mice painted with oxazolone is associated with T cells The results therefore showed that different sensitizers form immunogenic complexes with different cell populations, perhaps in this case becuase of the different water solubilities of FITC and oxazolone They also suggested that this may cause important differences in antigen presentation, for example in their association with different MHC products

Basophils and eosinophils in three strains of rats and in athymic (nude) rats following infection with the nematodes Nippostrongylus brasiliensis or Trichinella spiralis.

Abstract: A previous report showed that infection with the nematode Nippostrongylus brasiliensis stimulates a basophilia as well as an eosinophilia in the blood of August rats. The present study shows that blood levels of basophils and eosinophils were increased in two other rat strains, one inbred and one outbred, after infection with N. brasiliensis, and infection of two inbred rat strains with Trichinella spiralis also stimulated a basophilia as well as an eosinophilia. No increase occurred in basophils or eosinophils in athymic (nude) rats infected with N. brasiliensis, although both these cell types were found in the blood of control, specific pathogen free, nude rats in numbers comparable to those in specific pathogen free, heterozygote controls of the same strain. Rat basophils usually have few granules and in blood smears often appear as if they were partly degranulated. Basophils from uninfected nude rats contained more negative than positive staining granules compared with basophils from parasitized heterozygotes. The possession of small numbers of granules which vary in their reaction to stains of the Romanowski type is a normal feature of rat basophils in blood smears. Consequently rat basophils differ in these respects from those of other species.

The role of the liver in immunity to blood-stage murine malaria.

Abstract: Mice vaccinated with fixed parasitized red blood cells and Bordetella pertussis can clear an otherwise lethal Plasmodium yoelii infection in 7 days; this protection is abolished by splenectomy before vaccination. Most mice splenectomized following vaccination were able to clear their infections, although their recovery was delayed. When labelled parasitized red cells were injected into mice during an infection, splenic uptake fell from day 3 onwards while uptake by the liver increased. Lymphocytes (mainly T cells) formed the majority of the live cells extracted from livers 7 days after infection, although blasts and myeloid cells were also present. Infected livers from vaccinated mice contained most cells. Less marked increases were observed 7 days after P. berghei infection of vaccinated mice. Examination of liver tissue showed that the sinusoids contained increased numbers of cells and suggested that activation of Kupffer cells was occurring, particularly in vaccinated mice infected with P. yoelii. Homing experiments confirmed the increased trapping of various cells in livers of vaccinated mice infected with P. yoelii. These results suggest an important role for the liver in recovery from blood-stage malaria infection.

Immunochemical localization of collagen types and proteoglycan in pig intervertebral discs.

Abstract: Antisera were produced which recognized specifically native type I and type II collagens and proteoglycan. These were used in immunofluorescence studies to investigate the distribution of collagens and proteoglycan in intervertebral discs from adult and newborn pigs. Cervical, thoracic and lumbar discs gave similar staining patterns. In the adult, the outer 1 mm of the annulus fibrosus resembled a perichondrium and was negative for type II collagen. The inner regions of the annulus contained proteoglycan and both types of collagen, but these molecules appeared to have separate distributions. The nucleus showed no staining for type I collagen. Newborn pig discs differed from those of the adult in that type II collagen was restricted to the central notochord and to a narrow zone surrounding it. The newborn annulus was negative for type II collagen but reacted strongly with antibodies to both type I collagen and proteoglycan. It is suggested that during development of the pig annulus fibrosus, cells producing type II collagen may migrate into this area from the central regions.

Cyclosporin receptor on mouse lymphocytes

Abstract: Specific binding of [3H]-cyclosporin C (3H-CS-C), an immunosuppressive oligopeptide, was characterized on different mouse lymphocytes. The binding was saturable, time-dependent and reversible; and KD of 1.5 x 10(-7) M and maximum binding capacity Bmax of 35 pmol/4 x 10(6) cells was found for thymocytes. A computerized analysis of the data confirmed a single population of high affinity binding sites. Lymphocytes of different organs differed in their Bmax: thymus greater than spleen greater than mesenteric lymph node (pure T cells) greater than mesenteric lymph node (pure B cells). Erythrocytes did not show a specific binding.

Activation of human B lymphocytes. XII. Differential effects of in vitro cyclophosphamide on human lymphocyte subpopulations involved in B-cell activation.

Abstract: The differential effects of in vitro cyclophosphamide (CY) on subpopulations of normal human peripheral blood lymphocytes involved in the pokeweed mitogen-induced plaque-forming cell (PFC) response against sheep red blood cells were examined. It was found that the plaque-forming B cells in this system are sensitive to CY over a wide concentration range including concentrations which have a minimal effect on overall cell viability. Kinetic experiments revealed that CY exerts its inhibitory effect on the PFC response only if added very early in culture. Thus, it appears that in vitro CY must exert its inhibitory influence on an early phase of polyclonal B-cell activation. When T-cell enriched (TCE) populations were incubated overnight with high concentration CY and then added back in co-culture to fresh autologous B cells, significant enhancement of PFC responses was observed suggesting a selective inhibition or elimination of a regulatory suppressor cell population found in TCE lymphocyte preparations. Helper T cells are relatively resistant to the inhibitory actions of CY. Thus, human B cells appear to be most sensitive to CY, followed in sensitivity by the suppressor cell populations in the T-cell fraction with relative resistance of the helper T cells. These observations have direct relevance in understanding the mechanisms of selective action of CY on normal human lymphocyte subpopulations with possible application to disease states in man.

Insect erythrocyte agglutinins. In vitro opsonization experiments with Clitumnus extradentatus and Periplaneta americana haemocytes.

Abstract: The effect of naturally occurring haemagglutinins on the in vitro phagocytosis of sheep erythrocytes by the blood cells (haemocytes) of Clitumnus extradentatus and Periplaneta americana was studied. The results showed that the haemagglutinins in both species failed to act as opsonins. Indeed, in some instances, incubation of erythrocytes in haemolymph resulted in less avid ingestion as compared with the saline-incubated controls. This reduced phagocytosis was probably caused by the clumping of erythrocytes on the haemocyte monolayers, leaving fewer single red cells available for uptake. The possible roles of these erythrocyte agglutinins in the host defence systems of insects are discussed.