Showing papers on "Typing published in 1978"

Chapter VIII Serological Typing Methods of Leptospires

Abstract: Publisher Summary This chapter discusses the serological typing methods of Leptospires . They are the members of the Treponemataceae family. The genus includes strains which are parasitic or free living. Some strains may be pathogenic for man or various other animal species. When leptospira strains are classified, first the serogroup to which a strain belongs has to be determined by the microscopic agglutination test using selected rabbit group sera. The procedures used for the determination of the serotype status of a strain are derived from the definition of serotypes. Serotypes should be subdivided into varieties based on the presence of a thermolabile antigen. The relatively high specificity of host-serotype relationships means that accurate typing of isolated strains is one of the basic methods for epidemiological investigations. In studies dealing with pathogenic properties of strains-production of hemolysis, and lipases, knowledge of the serotype status is also essential.

Strong association between the HLA-Dw3-related B cell alloantigen -DRw3 and coeliac disease.

Abstract: The frequency of HLA A. -B. and -C antigens, of -DRw3 and the associated B-lymphocyte alloantigen -DRw3 has been studied in 68 children with coeliac disease (CD). CD was found to be primarily associated with the B-lymphocyte alloantigen, the relative risk being calculated to 54. The possible relation between the B-lymphocyte alloantigen DRw3 and -Dw3 is discussed. The high relative risk and the fact that 95% of the patients with probable or definite CD had the B-lymphocyte alloantigen DRw3, underline the diagnostic value of B-lymphocyte typing in coeliac disease.

Use of bacteriophage typing to distinguish Propionibacterium acne types I and II.

Abstract: Strains of serotypes I and II of Propionibacterium were compared for phage sensitivity. The two serotypes could be distinguished by using a typing set consisting of 16 bacteriophages at concentrations that demonstrated selective lysis of serotype I or II bacterial strains. Seven phage types were found; three were composed exclusively of serotype I, and four were exclusively composed of serotype II organisms. Generally, serotype I strains were more sensitive to phage lysis than were serotype II strains. No correlation was found between phage type and site of isolation.

Chapter V Principles and Practice of Typing Vibrio cholerae

Abstract: Publisher Summary Cholera is a disease of bacterial origin. It is not only important to recognize the disease clinically, but also to attempt as complete an identification of the causative organism as possible using various epidemiological typing procedures. This chapter explains the practical procedures currently available for the characterization, as well as a working background of the relevant theoretical knowledge. V. cholera is asporogenous, single curved or rigid rod with a single polar flagellum. It is indophenols oxidase positive and produces acid without gas from glucose. The aim of all typing systems is to identify strains within a species with a degree of precision that makes it safe to assume that all the isolates from an epidemic are truly identical and have therefore originated from a single parent strain. Of the three methods of typing V. cholera—serotyping, phage-typing and bacteriocin biotyping—serological typing was the earliest to be developed.

Experiences with the typing of coagulase-negative staphylococci and micrococci.

Abstract: Strains of coagulase-negative staphylococci and micrococci from many sources were biotyped and tested with a set of 20 phages, 19 of which were described by Dean et al. Strains resistant to many antibiotics were generally untypable with these phages. Nearly 50% of untypable strains could be typed by "reverse" typing--the characterisation of strains by the pattern of lysis given by their supernates on the propagating strains for the typing phages. This method was also used to clarify the relationship between isolates from an outbreak of septicaemia in a cardiac unit.

Comparison ofBacteriophage Typing, Serotyping, and Biotyping asAidsinEpidemiological Surveillance of Klebsiella Infections

Abstract: Bacteriophage typing was usedtosubdivide Klebsiella obtained frompatients ina surgical intensive careunitduring a 2-year period. The15phagesemployed totypethestrains were propagated byasoft-agar layer technique. Inail,23phage typeswere foundamong the120clinical strains. Thephagetypesofrepeat isolates were reproducible. Only70%ofthestrains tested were phagetypable, but whenusedinconjunction withcapsular serotyping andbiotyping, a muchgreater subdivision oftheKlebsiella strains was achieved. Theaddition ofphagetyping toserobiotyping forepidemiological analysis suggested thatthenumberofcrossinfecting Klebsiella strains intheintensive care unit was few,butthatthese strains persisted intheunitforlongperiods oftimeandcouldinfect different bodysites. Theimportance ofsubdividing strains ofa bacterial species into asmanytypes aspossible forepidemiological surveillance andinfection control hasbeenrecognized formanyyears. While somebacteria like Staphylococcus aureus canbesubdivided adequately byasingle typing method, thishasnotprovedsatisfactory for Klebsiella. Forthis organism, capsular serotyping(4,5,11,12),bacteriocin typing (9,15), biotyping (8,13), andbacteriophage typing (16) haveallbeentried; butapplied alone, each methodhaslacked sufficient precision forepidemiological needs. Inanearlier study(13), it wasfound that acombination ofserotyping and biotyping wasmorediscriminating thaneither methodalone, butapparently identical serobiotypesofKlebsiella havebeenobserved in whichnoclear epidemiological relationship existed (14). Thepresent investigation wasdesigned totest whether bacteriophage typing couldbeapplied tothetyping ofKlebsiella either asasingle technique orasa supplementary methodtogether withserotyping andbiotyping. Apersistentproblem ofserious infections caused byKlebsiella inpatients inthesurgical intensive care unit(SICU) ofaStockholm hospital provided theopportunity toinvestigate thereliabiity of phagetyping asanepidemiological tool. This report gives anaccount ofitsusebothwhen employed alone andasanadjunct toserotyping andbiotyping forthesubdivision ofnosocomial

Serologic examination of the Westphal-type lipopolysaccharides of Pasteurella multocida.

Abstract: The serologic specificities of the Westphal-type lipopolysaccharides from 16 serotypes of Pasteurella multocida were compared with those reported for the heat-stable typing antigens in the gel diffusion precipitin test. Like the heat-stable typing antigen, the Westphal-type lipopolysaccharide from each of the serotypes reacted only with its homologous antiserum in 14 of the 16 serotypes. The lipopolysaccharide from type strains representing serotypes 2 and 5 reacted with either of the corresponding typing sera, as did field isolates of these serotypes to a lesser extent. Although differences among the properties of these antigens were minor, the lipopolysaccharide appeared to be a major component of the heat-stable antigen responsible for the type specificity.

Low responsiveness in MLC induced by certain HLA--A antigens on the stimulator cells.

Abstract: An individual, BK, repeatedly gave typing responses against homozygous typing cells representing more than two HLA--D antigens Family studies showed that she had inherited the HLA--Dw2 and Dw7 determinants, in agreement with results from primed lymphocyte typing The HLA--A, B, C types of the stimulators giving rise to unexpected typing responses all involved the HLA--A1, A3 or A11 antigens The hypothesis of this specificity in low-responsiveness was confirmed in the independent stimulator sample provided by the 7th workshop homozygous typing cell panel The same pattern was observed when BK was tested as a responder towards related and unrelated heterozygous stimulators Furthermore, in three-cell experiments it was found that BK cells were able to suppress the response to the Dw-identical individual, BS, towards stimulators carrying HLA--A1, A3, or A11 This effect of BK's cells appeared to be radiosensitive We were not able to demonstrate suppressive supernatant factors in the relevant cultures, neither were we able to find circulating cytotoxic cells by the direct CML-technique, nor an accelerated cytotoxic response by the indirect CML-technique against targets carrying HLA--A1 or A3 This is the first demonstration of induction of suppressor cells in MLC by HLA--A, B, C antigens in the stimulator cells

Chapter V Phage Typing of Pseudomonas aeruginosa

Abstract: Publisher Summary Phage typing is one of the standard methods for epidemiological typing. For Pseudomonas aeruginosa , various phage typing procedures have been developed. These phage typing sets have mostly been developed locally. This chapter discusses basic mechanisms involved for phage–host-interaction, and methods used for phage typing of P. aeruginosa . Phages of P. aeruginosa may be isolated from sewage or from lysogenic isolates. Such strains are fairly common. The nucleic acid of the bacteriophages of P. aeruginosa may contain either DNA or RNA. The former are best known. They contain double-stranded DNA. The mole % (G + C) ratio of such phages has been reported as falling in the range 46–55%. The DNA-phages resemble the T-even phages of Escherichia coli in having a head and tail. Most have a morphology corresponding to group A of Bradley and Kay, but group B phage morphology has also been encountered. The tail lengths vary; upon contact with specific bacterial receptors, the sheath of the tails contracts.

Typing field isolates of infectious bronchitis by the plaque-reduction test.

Abstract: A technique is described for typing field isolates of infectious bronchitis virus by plaque-reduction assay of the serum antibody response of chickens experimentally infected with such isolates. Also reported are use of the technique with field isolates and a comparison of results obtained in plaque-reduction assay and in tracheal-ring organ-culture assay.

Phage typing of coagulase-negative staphylococci.

Abstract: 218 bovine and 116 human strains of coagulase-negative staphylococci and 46 bovine Staphylococcus aureus strains were typed with the Verhoef-phage set for human staphylococci and the Holmberg-set for bovine staphylococci. 22.5% of the bovine strains were lysed by the bovine phages and only 3.2% by the human phages. None of the bovine Staph. aureus strains could be typed. 21% of the human strains tested were lysed by the human phages and only 5.2% by the bovine phages. These results clearly demonstrate the need of separate phage sets for the typing of bovine and human coagulase-negative staphylococci.

Evaluation and application of an improved bacteriocin typing method for Klebsiella aerogenes.

Abstract: A bacteriocin typing method was evaluated using 200 strains of Klebsiella aerogenes, 93% of which fell into 11 distinct types. The typing technique was successfully applied to the monitoring and control of hospital cross-infection.

Tissue Typing of Cells in Culture. III. HLA Antigens of Established Human Cell Lines. Attempts at Typing by the Mixed Hemadsorption Technique

Abstract: Thirty established cell lines from solid human tumors were typed by the mixed hemadsorption technique with respect to the HLA-A and HLA-B and partly also the HLA-C series. All cultures exhibited unique antigenic patterns. The discriminatory potential was further increased very much taking into consideration one as yet undefined antigen series tentatively named Ek-1 to Ek-11. Sixteen cell lines not designated as HeLa cells but on various non-immunological indications suspected to be HeLa cell contaminants, all gave, with our present test, the same antigenic composition as HeLa cells or clones thereof. The mixed hemadsorption reaction is a highly sensitive and convenient method for immunological typing of cells in monolayer cultures. Some important implications of this are discussed.

False HLA--D assignments may be caused by cytotoxic responder lymphocytes.

Abstract: Lymphocytes from a healthy female repeatedly giving rise to MLC-typing response against HLA--D homozygous typing cells of three different specificities were investigated for cytotoxic capacity by the direct CML technique. Testing against a panel indicated the presence of circulating cytotoxic lymphocytes with specificity towards HLA--A2. When tested against selected HLA--D homozygous typing cells, the pattern of CML reactivity closely resembled the pattern of MLC-typing responses, i.e. typing responses were mostly restricted by the presence of HLA--A2 on the stimulator cells. This pattern was also found when time course studies of Cr--51 release were performed using experimental conditions identical to ordinary MLC typing, but involving chromium-51 labeled, irradiated homozygous typing cells as targets. These studies indicate that the presence of in vivo educated cytotoxic lymphocytes among the responder lymphocytes may in some instances mimic typing responses. Such lymphocytes are thought to lyse relevant stimulator lymphocytes prior to initiation of the proliferative response.

Use of a phage set for the ecological typing of coagulase-negative staphylococci.

Abstract: The staphylococcal flora of skin and acne lesions of 98 patients was analysed by the use of phage typing and biotyping methods. It appeared that in some individuals a relatively stable staphylococcal flora was present while others harboured 7 or more different strains. The same S. epidermidis strains were found on different skin sites and in acne lesions of a given individual. Examples of different carriage patterns were given.

Chapter I Serotyping of Bacteria

Abstract: Publisher Summary The use of serological methods for epidemiological typing is based upon the fact that microorganisms frequently show variations in antigenic constitution, not only between distantly related or unrelated organisms, but also within groups of closely related organisms. The identification of the antigens of microorganisms by means of specific antibodies, therefore, often allows very fine subdivision of microbial taxa, and greatly facilitates the surveillance and control of the spread of pathogenic micro-organisms. Microorganisms produce a wide variety of antigens, many of which can be utilized in identification and epidemiological typing: structural components of the cells, such as cell wall constituents, capsules or envelopes, flagella, fimbriae; secretion products of the cells, such as exotoxins or extracellular enzymes; or antigens contained in the interior of the cells. Many of these antigens can be utilized for typing purposes. A large variety of serological reactions are available. The reactions most commonly used for epidemiological typing are presented in the chapter.

A proposal for further modification of the phage-typing system for coagulase-negative staphylococci.

Abstract: Our phage-set, published in 1975 (6) was modified in that other staphylococcal hoststrains were found more suitable for the propagation. This new typing set of 15 phages should replace our old phage-sets. In comparing the phage-sets of Dr. Verhoef, Dr. Parisi and Dr. Blouse with our phages, the advantages of our new phage-set could be demonstrated. Lysogeny induction experiment with mitomycin C and UV-rays showed all staphylococcal host strains to be lysogenic. Conclusions of the studies performed were derived from and discussed.

Chapter III Bacteriophage Typing of Yersinia enterocolitica

Abstract: Publisher Summary Serological characterization of Yersinia enterocolitica is the epidemiological typing method that has gained the widest acceptance. No system for bacteriocine typing has been worked out;- there have been reports to the effect that this species does not have bacteriocins. This chapter discusses the available systems for phage typing of Y. enterocolitica. A considerable proportion of isolates of Y. enterocolitica are lysogenic. The frequencies vary, but on an average, 70–85% of strains may harbor phages. The methods described involve bacteria-free lysates spotted on to a number of sensitive strains. The Y. enterocolitica phages differ in their host ranges, such that different patterns of sensitivity are obtained with a given set of phages on different bacterial isolates. Host modifications of phage spectra are easily obtained on propagation in different susceptible strains. As natural variation in host sensitivity is considerable, the phage typing sets have been mostly composed of wild phages, but phages changed by host modification have also been included.

New HLA--D specificity included in Dw7.

Abstract: An HLA--D homozygous typing cell -- MS -- was found to induce typing responses with a phenotype frequency of 7% tested in a panel of 202 random individuals. All but two of these were positive for HLA--Dw7, which implies that the MS cell defines a split of Dw7. The new subgroups, MS, is associated with B12. Three individuals positive for MS but lacking Dw7 were found to be B13 positive. The relationship of the MS specificity to HLA--Dw11 has yet to be defined.

Chapter I Usefulness, Applications and Limitations of Epidemiological Typing Methods to Elucidate Nosocomial Infections and the Spread of Communicable Diseases

Abstract: Publisher Summary This chapter discusses the principal methods of epidemiological typing among which phage typing occupies a foremost place. It is designed primarily for the subdivision of microbial species whose serotype is usually determined previously. Serotyping is also applicable to a series of microbial species of medical interest. Phage typing is a method of bacterial differentiation based upon the sensitivity of strains to certain bacteriophages. The importance of each of the epidemiologic typing methods may differ from one species to another and many methods still need further improvement, or standardization, in both technique and international agreement. The importance of epidemiologic data in analyzing typing methods takes on a particular significance in the case of hospital infections. The utility of epidemiologic typing methods is of major importance in epidemic foci, whereas in sporadic cases it is of more restricted value. In various epidemiologic situations, the utility of these methods depends upon the stability of the types in time.

Tissue typing of cells in culture. IV. Cell surface antigens of tumor cell lines, not obviously belonging to the HLA-system.

Abstract: Studies on the HLA pattern of several human tumor cell lines by the mixed hemadsorption test and also studies on the discriminative patterns formed by a collection of sera on a number of cell lines and diploid cells have been reported elsewhere. It was noted during these studies that some sera reacted in a fashion indicating that they did not represent any of the HLA-A or -B series and probably not the HLA-C series either. The corresponding antigenic determinants were tentatively designated Ek-1 to Ek-11. The pattern of these antigens among the cell lines is given in a table and it seems apparent that the Ek-series considerably increases the cell identification potential of the typing results. So far, five of the sera determining the Ek-antigens have failed to be blocked by anti-beta-2-microglobulin, indicating that the antigens do not belong to the HLA-A, B or C series. Preparatory work for HLA-D typing is under way.

Chapter VII Phage Typing of Proteus

Abstract: Publisher Summary This chapter discusses the phage typing of Proteus . The presence of Proteus in the normal faecal and perineal flora makes endogenous infections a common occurrence, particularly with P. mirabilis, but cross-infections also occur. Proteus produces bacteriophage-tail like, proteinaceous bacteriocins. To elucidate transmission and spreading, typing methods are necessary. To ensure that the typing sets are applied on the same taxons at different centers, the major characteristics of the Proteus species are reviewed in the chapter. The indole positive proteae represent a difficult therapeutic problem on account of their multiple resistances to antibacterials. Antibiotic resistance transfer factors, transmissible by conjugation (R-factors) are common in the indole negative P. mirabilis that may acquire a resistance resembling that of the other species. By typing, one may distinguish between endogenous and exogenous infections, identify the likely sources and in a group of patients, differentiate between cross-contamination and isolated cases.

Chapter III Phage Typing of Escherichia Coli

Abstract: Publisher Summary This chapter discusses the phage typing of Escherichia coli . Based on the symptoms, epidemiological characteristics, and the type of pathogenic agent human enteric diseases are classified into two main groups: (1) the cholera-like syndrome, and (2) the dysentery-like syndrome. Enteric and extra-enteric diseases of animals manifest in diarrhoea or in generalized infection are caused by some definite serotypes of E. coli . The development of relevant laboratory methods has facilitated epidemiologic studies of infantile enteritis. Serological methods have been used to reveal pathogenicity of E. coli strains, however, biochemical and serological techniques have proved less suited for clarifying the route and source of nosocomial infections. Clinical and epidemiological observations accompanied by serological identification, phage and colicin typing have shown that certain sero-fermentative, phage or colicin types within the antigenic group O are involved in pathological processes causing diseases and outbreaks. Phage typing and additional typing procedures reveal the pathogenic role of serologically nonidentified or non-identifiable E. coli strains. The application of these procedures allows a further subdivision of frequent serogroups and serotypes, thus serving as an efficient and valuable epidemiological tool.

Mixed Lymphocyte Culture Search for HLA‐D Homozygous Typing Cells in the Hungarian Inbred Population of Ivád

Abstract: Six functionally HLA-D homozygous typing cells were identified by a restricted investigation into the Hungarian inbred population of Ivad. These putative HLA-D homozygous typing cells were then tested against a highly selected Scandinavian population sample of 60 individuals previously typed by histocompatibility reference reagents. Three different HLA-D specificities could thus be identified: one closely matching HLA-Dw5, another resembling the Oslo LDoH specificity, while the last seems to be unique. Only one of the typing cells thus ascertained were HLA-B homozygous and were selected on the basis of the Ivad family structure and not on the basis of serological HLA typing.

[Modified procedure for pyocin typing of Pseudomonas aeruginosa (author's transl)].

Abstract: The Procedure for pyocin typing of Pseudomonas aeruginosa isolations as proposed by GILLIES and GOVAN has been modified in the following aspects: strains are arranged in a symmetrical way, with a central producer zone and radial indicator streaks, optimal size of inocula for both producer (300 x 10(6)/ml) and indicators (50 X 10(6)/ml) was determined, unsupplemented Tryptic Soy Agar is used giving identical results to those when TSA is supplemented with 5% horse blood. The typing results obtained with this simplified and standardized procedure were identical with those from the cross streak method.

A complex of HLA-D specificities detected by HTC typing: Dw7, Dw11, and TMo.

Abstract: Homozygous typing cells defining HLA-D antigens related to Dw7 appear to identify a complex of partially overlapping structures. The relationships between these specificities were analyzed using 7th Workshop cells and other cells sent to the reference laboratory. The local cells JLe and KA seem to fit the antigen Dw11, which is in large part included in Dw7. TMo defines a component that is rare in normal whites and frequently observed in children with rheumatoid arthritis.