Sheep histo compatibility antigens: a population level comparison between lymphocyte antigens previously defined in France, England and Scotland, and sheep red cell groups

A comparison test was performed to look for correlations between the three nomenclature systems for sheep histo compatibility antigens which have been previously described in France, England and Scotland. 187 French sheep from a wide variety of breeds were typed for lymphocyte antigens with antisera which detect the OLA, P and ED series of antigens; they were also tested against. 387 uncharacterized French antisera. Six clusters of sera were found which showed correspondence between antigens of at least two of the three nomenclatures; five of these clusters gave high r values of 0.78–0.94. New antisera from French sheep were found which contributed to the above clusters but few additional clusters were noted. No correlation was found between any of the lymphocyte groups of antisera tested and the sheep red cell antigens which were also tested.     

Sheep lymphocyte antigens: A preliminary study

Sera from 287 sheep were screened for cytotoxic antibodies against sheep lymphocytes. Forty four antisera were selected which provisionally define 13 lymphocyte antigens. The frequency of these antigens was studied in 305 sheep from 8 flocks of different breeds. Family studies confirm that inheritance of sheep lymphocyte antigens is controlled by the autosomal codominant genes of at least 2 linked loci.     

Sheep lymphocyte antigens: a preliminary study

Sera from 287 sheep were screened for cytotoxic antibodies against sheep lymphocytes. Forty four antisera were selected which provisionally define 13 lymphocyte antigens. The frequency of these antigens was studied in 305 sheep from 8 flocks of different breeds. Family studies confirm that inheritance of sheep lymphocyte antigens is controlled by the autosomal codominant genes of at least 2 linked loci.     

Ovine lymphocyte antigens: a comparison of Australian and European antisera

Lymphocyte alloantigens were determined in 183 Australian merino sheep, using antisera from Australian and European laboratories. The study had two aims: (1) to compare reagents characterized in the different laboratories and to correlate antigen definition; and (2) to define lymphocyte antigens for use as genetic markers in two flocks of sheep which had been selectively bred for resistance or susceptibility to the intestinal parasite Trichostrongylus colubriformis, in order to extend a previous study which had indicated linkage between resistance to the parasite and the sheep major histocompatibility system. Good or excellent correspondence was found between four Australian and four European specificities and it was concluded that continued international collaboration would allow definition of markers for future genetic or disease susceptibility studies.     

An association between a lymphocyte antigen in sheep and the response to vaccination against the parasite Trichostrongylus colubriformis

Lymphocyte antigens were tested in sheep which had been selected for responsiveness to vaccination against the intestinal nematode Trichostrongylus colubriformis. These sheep had been bred in an assortative mating programme which produced offspring designated as either “high responders” or “low responders”, with highly heritable resistance or susceptibility.Ovine lymphocyte antigen (OLA) typing antisera were obtained from parous ewes in the course of matings which produced the high and low responder flocks. A particular antigen (SY1) was found to be present in high frequency on the lymphocytes of high responder (72·2%) and in lower frequency (21·9%) on the lymphocytes of low responder rams. In ewes, the frequency for high responders was 65·7% and for low responders it was 33·5%. A similar association between the SY1 antigen and low faecal egg count was found in random-bred sheep which had been vaccinated with irradiated larvae and challenged with normal larvae. The conclusion was drawn that this lymphocyte antigen was likely to be part of the sheep major histocompatibility complex which influenced the immune response of sheep to vaccination against the parasite.     

Presence of species-specific, monomorphic antigens on sheep and goat binucleate cells

Immunocytochemical assays for sheep and goat species-specific, monomorphic antigens were developed utilizing polyclonal antisera from sheep and goats immunized by interspecific pregnancy. The assays were applied to cell isolates from sheep and goat fetal cotyledons collected from allogeneic pregnancies at Days 35, 40 and 120 of gestation. The isolates contained 7 to 48% binucleate cells (BNC). Using these assays, the sheep-specific antigen was detected on sheep cotyledonary cell isolates on all days of gestation tested (P < 0.001); the assay also detected the antigen on the BNC subset of the cotyledonary cell isolate population (P < 0.001). The caprine-specific antigen was shown to be present on cotyledonary cell isolates (P < 0.05), although the presence of the antigen could not be demonstrated with statistical confidence on goat BNC due to insufficient numbers of discernible cells. Binucleate cells contribute to the formation of the syncytial layer of the placenta by fusing with maternal epithelial cells and with the syncytium. The species-specific antigen (or antigens) is present on BNC at the appropriate time of gestation at which it (they) could play a role in the humoral immune response to interspecific and hybrid pregnancies observed in ewes and does.     

Joint report1 of the First International Workshop on Lymphocyte Alloantigens of the Horse held 24–29 October 1981

Six equine lymphocyte alloantigen (ELA) specificities were defined by an international antiserum comparison test and workshop held in 1981. Twelve laboratories from four countries submitted 195 antisera for analysis. The antisera were exchanged among the 12 laboratories and tested in a standard lymphocyte microcytoxicity assay against the isolated lymphocytes at 1009 horses of several breeds. The data was pooled and analysed by a single computer analysis. The calculated χ² values of all cells with all antisera provided comparisons between antisera. Fifteen antisera clusters were formed by this analysis, but only six of these clusters met the criteria established by the workshop for the identification of ELA antigens. No horses of the cell panel positively reacted with more than two of these six specificities. The consensus of the participants, although not substantiated in this workshop, was that these six clusters of antisera define alleles of a single genetic region, the ELA region, and it is likely that this genetic region is the major histocompatibility complex of the horse.     

The relationship between ovine lymphocyte antigens and parasitological and production parameters in Romney sheep

The occurrence of ovine lymphocyte antigen (OLA) types in two flocks of New Zealand Romney sheep was examined in relation to resistance to nematode parasites [as judged by faecal egg counts (FEC)], plasma pepsinogen levels, liveweight and weight gains. A panel of OLA-typing antisera (SY 1-16) which determine class 1 MHC antigens of the sheep was used. The OLA combination SY 1a + 1b was found exclusively in Romney sheep of both flocks having below average FEC, but was present in low frequency (5%). In one flock, sheep possessing this antigen combination had consistently lower FEC from weaning to 1 year of age than sheep without this combination. SY 6 occurred significantly more frequently in above average FEC sheep and was associated with significantly higher FEC during secondary challenge infection. Plasma pepsinogen levels were significantly lower in those sheep possessing SY 2 or SY 3 but these OLA types were not associated with lower than average FEC. No OLA type was associated with above average weight gain but in one flock sheep with SY 1b and SY 1a + 1b had significantly lower weight gains between weaning and 6 months of age than sheep without these OLA types. A similar association was not found in the other flock. Sheep in one flock with SY 16 were significantly heavier than those without this antigen. No other associations between OLA types and liveweight were found.     

Uniformity of protective antigens among isolates of the cattle tick, Boophilus microplus

Abstract. Gut membrane antigens were extracted from ten isolates of the cattle tick Boophilus microplus; the antigen extracts were probed with bovine antisera and three murine monoclonal antibodies (mAbs) in Western blots and dot-ELISA. The antisera had been obtained from cattle which were vaccinated with larval and gut extracts of B.microplus , and which were subsequently protected (84% and 94% respectively) against challenge with B.microplus. One of the mAbs (QU13) has been demonstrated to precipitate protective antigens from the midgut of B.microplus. Gut antigens from all ten isolates displayed similar reactivity profiles against bovine antisera and also against mAbs in Western blots. The end-point titres of antigens in dot-ELISA showed four-fold variation between isolates against bovine antisera, and also against mAb QUI 3. Larval membrane antigen extracted from N-strain B.microplus reacted with QU13 in dot-ELISA, indicating that protective antigens are common to both larval and adult stages of B.microplus. It was concluded that protective antigens recognized by QUI3 and antigens recognized by sera from protected cattle were conserved between the ten isolates examined, and between life-cycle stages.     

Echinococcus granulosus: host lymphocyte transformation by parasite antigens.

Lymphocyte transformation, measured by in vitro tritiated thymidine incorporation, and indirect hemagglutination tests were carried out on hydatid patients and normal individuals using sheep and human hydatid fluid or scolex antigens. The hydatid patients showed statistically significant lymphocyte transformation with human and sheep hydatid fluid or scolex antigens when compared to normal individuals. The indirect hemagglutination tests resulted in high titers of antibody with sheep or human hydatid fluid antigens, while very low titers were obtained with scolex antigens. Unlike in the indirect hemagglutination test, the source of the antigen, scolex or fluid, was not of consequence in the lymphocyte transformation test. Furthermore, there was no correlation between the results of the serologic and lymphocyte transformation tests, since some patients with very high lymphocyte stimulation indices produced low indirect hemagglutination titers and vice versa. Similar results were obtained from rabbits which were immunized with sheep hydatid fluid or scolex extracts. The skin tests were of the immediate type of hypersensitivity reactions. Delayed skin reactions did not occur in spite of the presence of sensitized lymphocytes in the blood of the immunized rabbits.     

Joint report of the First International Workshop on Lymphocyte Alloantigens of the Horse held 24-29 October 1981

Six equine lymphocyte alloantigen (ELA) specificities were defined by an international antiserum comparison test and workshop held in 1981. Twelve laboratories from four countries submitted 195 antisera for analysis. The antisera were exchanged among the 12 laboratories and tested in a standard lymphocyte microcytoxicity assay against the isolated lymphocytes at 1009 horses of several breeds. The data was pooled and analysed by a single computer analysis. The calculated chi 2 values of all cells with all antisera provided comparisons between antisera. Fifteen antisera clusters were formed by this analysis, but only six of these clusters met the criteria established by the workshop for the identification of ELA antigens. No horses of the cell panel positively reacted with more than two of these six specificities. The consensus of the participants, although not substantiated in this workshop, was that these six clusters of antisera define alleles of a single genetic region, the ELA region, and it is likely that this genetic region is the major histocompatibility complex of the horse.     

Group antigens in slow-growing rhizobia

Summary Internal group antigens of several slow-growing and fast-growing Rhizobium strains were tested by gel-diffusion against antisera to three strains of Rhizobium japonicum. At least one, generally two common antigens were found in 13 strains of R. japonicum, 4 strains of R. lupini, 4 strains isolated from cowpea and two slow-growing strains isolated from Lotus. Forty-six fast-growing rhizobia (including two from Lotus and 4 from Leucaena leucocephala) were clearly distinguished from the slow-growing strains in tests with the same antisera. They were wholly negative (9) or gave a much weaker non-identical line with one antiserum (24 strains), two antisera (8) or three antisera (5). The 5 strains of agrobacteria grouped with the fast-growing rhizobia.     

The definition of five B lymphocyte alloantigens closely linked to BoLA class I antigens

B lymphocyte alloantigens in cattle were identified by serological analysis. Alloantisera were raised by skin implant immunization or leucocyte immunization and were absorbed with platelets to reduce class I-specific antibody activity. Leucocyte absorptions were done to reduce the complexity of some antisera. A panning technique was used to prepare B-enriched and B-depleted lymphocytes. Antisera which displayed anti-B cell activity over a number of dilutions were tested against 115 Charolais cattle, and 13 antisera were used to define five B lymphocyte alloantigens. These antigens were present on B lymphocytes but did not appear to be present, at least at the same density, on the majority of T lymphocytes or platelets. Family studies suggested that these antigens are coded by one or two loci which are closely linked to the bovine class I loci. These results suggest the five antigens are class II antigens of the major histocompatibility complex (MHC) of cattle.     

Serologically detected lymphocyte antigens in Holstein cattle

Lymphocytes from 103 Holstein cattle were tested with 11 antilymphocytotoxic sera. Four of these sera were produced by whole blood immunization; these generally yielded lymphocytotoxicity against a large number of animals in each test panel. The majority of the sera were collected from parous cows which had never been immunized. Observations about this latter group of sera are (1) lymphocyte antibodies, may occur by alloimmunization in foetal-maternal interaction, (2) normal sera from non-immunized parous cows generally had a narrower specificity of antibodies than from parous cows immunized with blood from unrelated animals and in some cases these antisera may be monospecific, and (3) these sera from parous cows are easy to obtain without the need for laborious immunizations. Analysis of these lymphocytotoxic sera indicate several reagents were obtained which possessed different antibodies; these were useful in detecting polymorphism of cattle lymphocyte antigens. Using these 11 sera, an analysis of the reactions patterns among 103 Holsteins, including parent-offspring data resulted in the postulation of several alleles. These data suggest that cattle lymphocyte antigens are very polymorphic and inherited.     

Serologically detected lymphocyte antigens in Holstein cattle1

Lymphocytes from 103 Holstein cattle were tested with 11 antilymphocytotoxic sera. Four of these sera were produced by whole blood immunization; these generally yielded lymphocytotoxicity against a large number of animals in each test panel. The majority of the sera were collected from parous cows which had never been immunized. Observations about this latter group of sera are (1) lymphocyte antibodies may occur by alloimmunization in foetal-maternal interaction, (2) normal sera from non-immunized parous cows generally had a narrower specificity of antibodies than from parous cows immunized with blood from unrelated animals and in some cases these antisera may be monospecific, and (3) these sera from parous cows are easy to obtain without the need for laborious immunizations. Analysis of these lymphocytotoxic sera indicate several reagents were obtained which possessed different antibodies; these were useful in detecting polymorphism of cattle lymphocyte antigens. Using these 11 sera, an analysis of the reactions patterns among 103 Holsteins, including parent-offspring data resulted in the postulation of several alleles. These data suggest that cattle lymphocyte antigens are very polymorphic and inherited.     

Lymphocyte antigens in sheep

This paper describes the detection of 13 lymphocyte antigens in sheep. The results obtained from family studies are consistent with the hypothesis that at least 12 antigens are under the control of a single genetic system. The distribution of antigens in the population suggests that the system contains two loci. The 13 antigens were compared with those previously reported. Only one additional specificity was found.     

Species-specific antigens ofMycoplasma hyopneumoniae and cross-reactions with other porcine mycoplasmas

Cell proteins from the porcine mycoplasmasMycoplasma hyorhinis, M. hyopneumoniae, andM. flocculare have been analyzed by SDS-gel electrophoresis and immunoblotting. The protein profiles ofM. hyopneumoniae andM. flocculare were similar, but the protein profile ofM. hyorhinis was quite different from the others. Antisera prepared against whole cells of the above three mycoplasmas were used in immunoblotting of electrophoretically separated antigens and in enzyme-linked immunosorbent assay. One major antigen, which had a molecular weight of 73 k, was found to be common to all three mycoplasmas. Another major antigen, with a molecular weight of 41 k, was common toM. hyopneumoniae andM. flocculare and may also be present inM. hyorhinis. Several antigens of comparatively high molecular weights (108 k, 102 k, 93 k, 89 k, and 87 k) seemed to be specific forM. hyopneumoniae. Three antisera prepared by immunization of rabbits with immunoprecipitates obtained by crossed immunoelectrophoresis ofM. hyopneumoniae were also used in blotting experiments. One of these antisera was found to be directed against the 73 k antigen common to the three porcine mycoplasmas investigated. The other two antisera were directed againstM. hyopneumoniae-specific antigens with molecular weights of 74 k, 58 k, 45 k, 44 k, and 38 k.     

Characterization of Candida antigens by crossed-immunoaffinoelectrophoresis

The antigens of three Candida albicans strains (3153 A, 3156 B and CBS 1905) and one C. tropicalis strain were studied by means of crossed-immunoaffinoelectrophoresis with the corresponding polyvalent antisera. Most antigens (from 63.8% to 77.7% depending on the strain) were bound to concanavalin A-sepharose and about 20% to blue cibacron-sepharose for all the strains tested. Free concanavalin A, wheat germ lectin-sepharose and Helix pomatia lectin-sepharose revealed differences between C. albicans 3153 A and C. albicans CBS 1905 on the one hand and C. albicans 3156 B and C. tropicalis on the other, since affinity percentages were from 4.2 to 10.2 and from 14.2 to 20.0 respectively. Among 10 previously described species-specific antigens of C. albicans, 4 were never bound and 5 were bound to concanavalin A-sepharose which was considered an unsuitable agent for antigen purification since it retained 77% of C. albicans antigens. One important species-specific antigen was bound to blue cibacron sepharose and the corresponding purification could be undertaken. Similar results were found for 12 species-specific antigens of C. tropicalis. Blue cibacron-sepharose as well as wheat germ lectin or Helix pomatia lectin-sepharose were found suitable agents for purification of some of them.     

Soluble and membrane-bound enzyme-active antigens of rat-liver lysosomes.

Secondary lysosomes were isolated from rat liver and separated into a soluble and a membrane fraction. Plasma membranes and microsomes were also isolated and antisera against the various fractions were prepared in rabbits. Lysosomal content and detergent-solubilized membrane fractions were analysed in two-dimensional immunoelectrophoresis (crossed immunoelectrophoresis). The immunoprecipitates were stained by histochemical procedures for different enzyme activities such as phosphatases, non-specific esterase, arylsulphatase, glycosidases and L-leucyl-beta-naphthylamidase. When lysosomal content was tested against its corresponding antiserum, 17 different precipitates could be seen. Most of the enzyme activities tested were shown to reside separately in one or a few precipitates each. In contrast, when the membrane extracts were investigated, a more polymorphic pattern of enzyme-active precipitates appeared. Thus, when lysosomal membrane extracts were reacted with homologous antiserum 11 precipitates with acid phosphatase activity were obtained. Several of the antigens were electrophoretically different and immunologically non-identical. As expected from the biology of secondary lysosomes, many of their antigens were also found in microsomes and/or plasma membranes, but several antigens unique for lysosomes were detected concomitantly. Closer analysis of these results indicated that several seemingly identical enzyme-active proteins occurred both in soluble and membrane-associated forms. However, while many of the membrane antigens expressed 2-4 different enzyme activities, only one activity was detected in individual precipitates of the lysosomal content. Thus, acid phosphatase activity was found together with esterase activity in three membrane-associated antigens. The precipitates formed by two of these also stained for arylsulphatase and nucleoside tri-, di- and monophosphatase activities. L-Leucyl-beta-naphthylamidase activity was found in one additional acid-phosphatase-active precipitate.     

Human cell surface antigens coded by genes on chromosome 21

Clones of man-mouse hybrids derived from four different crosses which retained a very limited number of human chromosomes were studied for the expression of human cell surface antigens. In testing a variety of rabbit antisera to human cells and tissues, it was found that an antiserum to Daudi cells recognizes human species-specific antigen(s) on three ‘WA’ clones, all of which carried human chromosome 21. Absorption of the antiserum with any of the clones abolished its activity against all clones, indicating that the antiserum recognized the same antigen(s) on these clones. The antigen(s) was shown to be present on normal human lymphocytes, more on B than on T cells, but apparently absent from erythrocytes. C3H mice, from which the murine parent originated, were immunized with the WA clones carrying human chromosome 21. The resultant antisera reacted with clones carrying chromosome 21 but not with clones which did not retain this chromosome, even though some of these clones possessed many other human chromosomes. The murine antisera reacted with some, but not all, human peripheral blood lymphocytes tested. Absorption studies clearly showed the multiple nature of the antigens recognized by these antisera. Studies on cells of identical twins provided evidence that these antigens are inheritable.