Joint Report of the Fourth International Bovine Lymphocyte Antigen (BoLA) Workshop, East Lansing, Michigan, USA, 25 August 1990.

Blood samples from 54 animals were exchanged between 15 laboratories in nine countries to improve and expand BoLA class I and class II typing. A total of 27 out of 33 (82%) of previously accepted BoLA-w specificities were represented within the cell panel. Seventeen new serum-defined BoLA specificities were accepted by the workshop participants, thus expanding the number of internationally recognized BoLA specificities to 50. The large number of new specificities detected resulted from the number of serological reagents used (n = 1139) and the genetic diversity of the cell panel. Confidence derived from the high percentage of agreement between the laboratories on antigen detection (97.3%; r = 0.84) permitted the removal of the workshop (w) notation from 23 BoLA-w specificities and their acceptance as full status BoLA-A antigens. Two new non-BoLA antigens were also detected, one completely included within the red blood cell factor S' (BoLy-S'), whereas a second (BoLy-w1) did not show any association with tested red blood cell factors. A comparison between serological, isoelectric focusing (IEF) and DNA typing for BoLA class II polymorphism was conducted with a subset of workshop cells. Correlation between the three methods was significant for three combinations of alleles. Three other serologically defined class II specificities were correlated with DR and/or DQ restriction fragment length polymorphism (RFLP) types, whereas six additional IEF types were correlated with DR and/or DQ RFLP types (r greater than or equal to 0.50). Several new IEF, DRB, DQA and DQB RFLP patterns were identified. In 46 animals that were typed for BoLA-DR and DQ genes by RFLP analysis, 46 different BoLA haplotypes were tentatively defined. These 46 haplotypes were distinguished by 31 serologically-defined BoLA-A alleles (and 2 'blanks'), 15 DRB RFLP types (plus up to 10 new DRB RFLP patterns) and 23 DQA-DQB haplotypes.

New blood group factors Es, Et and a new allele Ebdgjmt (E16) in the pig E blood group system.

By immunizing a miniature sow a monovalent reagent (later designated anti-Es) was prepared, detecting an alternative antigen to the Ej. Blood group factors Ej and Es thus form the fifth genetically closed E subsystem. Analyses of selected raw sera containing anti-Ej led to the determination of a further Ej subgroup (designated Et) which is antithetical, mutually excluding with the blood factor Er. New blood factor Et is inherited by alleles Edeghjmnt (= E9) and (= E16). The investigation in pig breeds kept in CSFR indicated that allele Edeghjmnt occurs in Black and White Prestice breed (qE9 = 0.076 +/- 0.010) while allele Edeghjmnr (= E14) only in miniature pigs (qE9 = 0.147 +/- 0.011) and in wild pigs. In an élite herd of Swedish Landrace kept in CSFR a new complex allele Ebdgjmt (= E16) was found. Its frequency in the population studied was 0.058 +/- 0.022.

[Leukocyte migration inhibition after experimental trypanosome infection in cattle]. / Leukozytenmigrationshemmung nach experimenteller Trypanosomeninfektion beim Rind.

Blood serum from cattle experimentally infected with trypanosomes was tested for its activity influencing granulocyte migration. Pooled porcine granulocytes were used in the migration assay. The inhibitory migration activity observed in serum samples of trypanosome infected animals implies the presence of mediators of cellular immunity. Values of migration indices express reciprocal events of inhibitory and stimulating events in infected animals. This study allowed to follow at least some aspects of the very complex cellular immune system and its functioning. The observed differences in migration values in serum of each animal speak for an individual immunological capacity to defy trypanosome infections. The variability in occurrence of the first inhibitory activity after infection supports the view of individual responsiveness. Distinct differences in migration values were observed in Dahomey cattle after primary and secondary challenge with trypanosomes. Serum from reinfected animals exhibited a marked decrease in inhibitory activity as compared to samples obtained after first infection. These observations suggest a modulation of the individual immune response after multiple challenge with trypanosomes of the same strain. This study demonstrates the involvement of cell mediated immune responses to trypanosome infections.

Joint report of the Third International Bovine Lymphocyte Antigen (BoLA) Workshop, Helsinki, Finland, 27 July 1986.

Two hundred and eighty-two alloantisera were submitted by 20 participating laboratories from 13 countries and tested against lymphocytes of 1298 cattle. The cell panel consisted of samples from 38 Bos taurus breeds, 11 Bos taurus crossbreeds, 4 Bos indicus breeds, 6 Bos taurus x Bos indicus, and a variety of other crossbred populations. Using a standardized lymphocytotoxicity test, all 17 previously identified BoLA specificities were confirmed. The workshop produced agreement on 16 new lymphocyte alloantigenic specificities. Three of the new specificities behaved as splits of previously identified BoLA specificities. Four of the new specificities behaved as alleles at the agreed BoLA-A locus. Seven new specificities are tentatively assigned to the BoLA-A locus but require further definition. Two new specificities may represent products of a second closely-linked BoLA locus.

Chemical characterization of porcine blood serum components with A and SLA activity.

The porcine A blood group substance is found in the serum as a lipid and, additionally, in certain animals, as a glycoprotein. Swine lymphocyte antigens (SLA) occur in the serum only as glycoproteins. Heat treatment of the solid residue obtained by lipid extraction yielded a water-soluble fraction with low protein content, high A activity, but no SLA activity. Poly(glycosyl)ceramides with SLA activity do not occur in the serum; poly(glycosyl)ceramides with A activity cannot be excluded. Desialylation of protein fractions has no effect on A and SLA activity. Both A and SLA activities of protein fractions are stable to mild alkaline hydrolysis thus indicating N-glycosidic carbohydrate-peptide linkages.

Analysis of alloantisera against bovine lymphocytes. Joint report of the 1st International Bovine Lymphocyte Antigen (BoLA) workshop.

The results and agreements of the 1 international BoLA workshop, held in Edinburgh, Scotland in August 1978, are reported. Most of these concern the results from a comparison test of 249 alloantisera to bovine lymphocytes, the antisera being contributed by 9 laboratories. These sera were compared directly in Edinburgh on a panel of lymphocytes from 130 cattle of 21 breeds. In the microlymphocytotoxicity test used 75% of the sera reacted. Sixty eight of these sera were grouped into clusters according to their reaction patterns against the lymphocyte panel. Eleven of these clusters were clearly defined and were given workshop BoLA designations. In addition 22 sera were assigned to subgroups of the agreed clusters. There was no evidence that the method of production of the sera had any effect on their specificity. Although genetic data was not available, the phenotypes of the test panel of lymphocytes are consistent with the clusters detecting antigens controlled by multiple alleles at a single autosomal locus. It was agreed to name the genetic region where this putative locus is located BoLA (bovine lymphocyte antigen).

PGM3 locus and its genetic polymorphism in lymphocytes of the pig.

PGM3 activity was investigated by means of horizontal starch gel electrophoresis. In the pig of the German Landrace three different phenotypes have been recognized: F, S and FS. Family studies suggest the occurrence of at least two alleles--PGM3F and the PGM3S at an autosomal locus.