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Biomedical subjects

J R Batchelor

Publications and source records attributed to J R Batchelor.

At least 163 records · Page 9Linked to original sources

Immunological enhancement of rat renal allografts using rabbit antisera with specificity for rat transplantation antigens.

Rabbits immunized with particulate and soluble preparations of rat lymphoid tissue of the HO strain produced antisera which reacted without strain specificity on rat lymphocytes. Absorption of the sera with tissue from the AS strain of rat removed the antibodies reacting with AS tissue leaving activity against HO cells only. Studies with backcross rats showed that the antigens detected by these sera were products of the AgB genes or genes segragating with them. The immunosuppressive activity of rabbit antisera specific for Ag-B5 rat transplantation antigens was tested in a rat renal allograft assay. Some of the antisera markedly prolonged the survival of (AS X HO)F1 kidneys transplanted to AS rats. The prolongation of graft survival was not due to ALS activity since the sera were active in the absence of antibody directed against recipient antigens. There was no correlation between in vivo enhancement and anti-donor lymphocytotoxic titres of the xenoantisera.

Absorption↗

Histocompatibility antigens in diabetic identical twins.

84 pairs of diabetic identical twins were HL-A typed. 22 were maturity-onset diabetics (diagnosed after age 45); all were concordant and they showed no disturbance of HL-A frequencies. Of the remaining 62 pairs of juvenile-onset diabetics, 31 were discordant (only one twin diabetic) and 31 concordant (both twins diabetic). The frequency of the W15 antigen was equally increased in both the concordant and discordant pairs; HL-A8 was increased only in the concordant pairs. The fact that W15 is increased in the discordant pairs shows that there is genetic predisposition to diabetes even in these twins; the fact that HL-A8 is not increased suggests that different alleles may underlie susceptibility in the two groups of twins.

Alleles↗

The role of the spleen in the rejection and enhancement of renal allografts in the rat.

As rats were splenectomised up to 7 weeks before or at the time of receiving an (AS times August)F1 kidney allograft. Only 2 of 19 splenectomised recipients rejected their grafts within 12 days, and 14 of the 19 survived for more than 100 days. All 19 splenectomised recipients had a marked and often complete suppression of the lymphocytotoxic antibody response to the graft. In contrast, splenecotomy had no effect in suppressing the rejection of (AS times August)F1 renal allografts transplanted to AS recipients previously immunised with August lymphoid tissue, or in AS recipients of homozygous August renal allografts. Splenectomised recipients could be reconstituted with spleen cells from sensitised but not from normal AS rats. Splenectomy was found neither to augment nor diminish the effectiveness of passive enhancement of (AS times August)F1 or August kidneys in AS recipients. Splenectomy of AS recipients 2 or 4 days after an (AS times August)F1 renal allograft was as effective as pregraft splenectomy in suppressing rejection, but there was a deficiency of long survivors in a group splenectomised 1 day after grafting. A working hypothesis to explain these results is presented, and their clinical relevance is discussed.

Animals↗

Prevention of blood transfusion-induced immunization against transplantation antigens by treatment of the blood with antibody.

The experiments reported show that alloantisera directed against the transplantation antigens of allogeneic blood will completely suppress (1) the lymphocytotoxic antibody response to the blood and (2) its ability to sensitize against renal allografts. AS (Ag-B1) rats injected i.v. with 1 ml of August (Ag-B5) blood gave a strong primary (mainly IgM) and secondary (IgG) lymphocytotoxin response. If the August blood was mixed with AS anti-August serum in vitro before injection, the lymphocytotoxin response was completely suppressed. However, rats given the blood-antiserum mixture gave a primary IgM response upon rechallenge with blood. Rats previously primed with blood had substantial but only partial suppression of the secondary response if the secondary stimulus was given as a blood-antiserum mixture. An AS anti-Wistar (Ag-B2) serum, which showed only weak serological cross-reaction with August lymphocytes, could suppress the lymphocytotoxin response to August blood. A protocol of widely spaced injections of August blood was found to sensitize AS rats to (AS X August)F1 renal allografts. If the blood injections were given as a blood-antiserum mixture, sensitization was prevented. In addition, the blood-antiserum mixtures were found to induce a slight degree of immunosuppression. The clinical application of this approach to preventing blood transfusion-induced sensitization is discussed.

Animals↗

Histocompatibility antigens in active chronic hepatitis and primary biliary cirrhosis.

The frequency of antigens HL-A 1 (48%) and HL-A 8 (52%) in 54 patients with active chronic hepatitis from south-east England was significantly higher than in 89 control subjects from the same region (22% and 17% respectively). No correlation could be detected with the age and sex of the patients or with the presence of a particular immunological abnormality but the frequency of HL-A 1 and HL-A 8 was much lower in the nine patients who were positive for HBAg than in the 45 HBAg-negative cases. These results provide further evidence of the importance of genetic factors in active chronic hepatitis. In contrast the frequency of HL-A 1 and HL-A 8 in primary biliary cirrhosis, both in 45 patients from south-east England and in 28 patients from western Scotland, was not significantly different from that found in control groups from the same regions.

Age Factors↗

The Rosette inhibition test in skin-grafted patients.

The rosette inhibition test was performed on lymphocytes from five patients who received viable allogeneic skin grafts after a severe burn injury. Serial tests were done to ascertain whether a change in the minimal inhibitory concentration of antihuman lymphocyte globulin needed to inhibit rosette formation by 25% was specifically associated with rejection of such a graft. No such change was observed.

Adolescent↗

Rosette inhibition test in severely burned patients.

The rosette inhibition test has been advocated as a test of immune reactivity in patients given transplants. We have done the test in lymphocytes from patients with severe burns, non-burnt control patients, and normal subjects. There was no correlation with the period of immunosuppression which follows a severe burn, though both groups of patients showed a wider range of minimal inhibitory concentrations (M.I.C.) than the normal group. Wide day-to-day variation of M.I.C. in burn and control patients was noted; this seemed to correlate with the ratio of sodium to potassium excreted in the urine. In-vitro experiments suggest that the M.I.C. is correlated with a plasma constituent which may be similar in action to hydrocortisone and that the rosette inhibition test is not a direct measure of immune reactivity.

Alanine Transaminase↗