Campath-1M--prophylactic use after kidney transplantation. A randomized controlled clinical trial.

Campath-1M is a rat monoclonal IgM antibody that binds human complement and recognizes virtually all peripheral human mononuclear cells. It is known to be effective in T cell depletion of bone marrow grafts, and encouraging results were obtained in a pilot study in which the antibody was used in prevention and treatment of rejection of kidney, pancreas, and liver allografts. In this randomized controlled clinical trial, Campath-1M has been evaluated as a prophylactic agent following renal allografting. It is shown that patients who received a 10-day course of the antibody immediately postoperatively, in addition to standard therapy with high-dose cyclosporine (17 mg/kg), experienced a significantly lower incidence of early acute cellular rejection than control patients who received cyclosporine alone. There was no evidence of "rebound" rejection following the end of antibody treatment to suggest that rejection had merely been delayed. However, patients who received this additional immunosuppression experienced a significantly higher incidence of serious infections than controls, this negating any benefit from the treatment in terms of graft survival. Thus, a monoclonal antibody of broad specificity directed against lymphocytes may be effective as a prophylactic agent after organ transplantation but its use should be accompanied by a reduction in other immunosuppressive drugs

Difficulties in the ascertainment of C9 deficiency: lessons to be drawn from a compound heterozygote C9-deficient subject

A group of patients with long-surviving mismatched kidney allografts were investigated for complement function using haemolytic assays in agarose gels. One patient was found to have no alternative pathway activity but a low normal classical pathway. Surprisingly, investigation revealed that the patient’s complement was normal for all components except C9, which was functionally absent. The patient was shown to be heterozygous for DNA markers in the C6, C7 and C9 region of chromosome 5 and therefore appears to be a compound heterozygote for two uncharacterized C9 deficiency genes. Serological analysis by ELISA revealed that he has trace concentrations of a non-functional C9 molecule. Western blot analysis was not sufficiently sensitive to permit detection of this molecule. We hypothesize that the patient is heterozygous for a complete deficiency of C9 and for a gene directing hyposynthesis of a defective C9. We also suggest that C9 deficiency may be more common among Caucasians than has been reported

Serological identification of Ia antigens: report of a British region Ia workshop.

In preparation for the 7th International Histocompatibility Workshop 13 laboratories in the British Region participated in a local workshop. One hundred and twenty-three sera which had been previously shown to have activity on either normal B cells, CLL cells or B cell lymphoid lines in the absence of HLA-A, B or C activity were exchanged between the laboratories. These sera were tested on a total of 212 B cells, 101 CLL cells, 76 T cells and 76 lymphoid cell lines. The data was collected and analyzed in Oxford. The analysis showed that six groups of sera could be distinguished. When these groups were compared with the D locus typing of some of the lymphoid lines which were derived from individuals used as MLC typing cells, they were seen to have significant associations with D locus antigens. The serological groups defined were therefore given numbers corresponding to the D locus numbers they associate with, i.e. UK1 is associated with DW1 and so on for UK2, 3, 4, 5 and 7. Comparison of typing techniques showed that long incubation both with antiserum and then with complement, 1 hour + 2 hours gave the best and most reproducible reactions on normal B cells. Residual anti-HLA-A, B or C activity in some of the sera even after platelet absorption showed the importance of adequate checking on T cells after absorption

Serological identification of Ia antigens: report of a British region Ia workshop.

In preparation for the 7th International Histocompatibility Workshop 13 laboratories in the British Region participated in a local workshop. One hundred and twenty-three sera which had been previously shown to have activity on either normal B cells, CLL cells or B cell lymphoid lines in the absence of HLA-A, B or C activity were exchanged between the laboratories. These sera were tested on a total of 212 B cells, 101 CLL cells, 76 T cells and 76 lymphoid cell lines. The data was collected and analyzed in Oxford. The analysis showed that six groups of sera could be distinguished. When these groups were compared with the D locus typing of some of the lymphoid lines which were derived from individuals used as MLC typing cells, they were seen to have significant associations with D locus antigens. The serological groups defined were therefore given numbers corresponding to the D locus numbers they associate with, i.e. UK1 is associated with DW1 and so on for UK2, 3, 4, 5 and 7. Comparison of typing techniques showed that long incubation both with antiserum and then with complement, 1 hour + 2 hours gave the best and most reproducible reactions on normal B cells. Residual anti-HLA-A, B or C activity in some of the sera even after platelet absorption showed the importance of adequate checking on T cells after absorption