Lymphocytotoxic antibodies and antiglobulins in renal allograft recipients. Correlative study with acute rejection

In 45 patients who received kidney transplants, both homologous and heterologous human antiglobulins (anti-Ig) and HLA cytotoxic antibodies have been studied before and after transplantation and in some cases after nephrectomy. A similar study has been performed in a control group of 1,019 healthy blood donors and in 130 patients with acute or chronic glomerulonephritis. After transplantation, homologous anti-IgG were found in 60% of the patients, as compared with 3.5% in the healthy blood donors and 21% in patients with various forms of glomerulonephritis. This difference is particularly striking in sera obtained prior to nephrectomy; the presence of anti-IgG and cytotoxic antibodies in the same patient being significantly associated with early transplant failure. Anti-IgA were found in 75% of the patients with transplants and in 37% of the patients with glomerulonephritis. There was no relationship between the anti-IgA and the outcome of the graft. On the other hand, heterologous anti-Ig were unchanged in the three groups investigated. The mechanism of formation of the anti-IgG is not clear. They are probably antibodies against antigenic structures of the patient's own antibodies, previously combined with a soluble antigen or an antigen on the transplant that has undergone molecular transformation in the course of this reaction. Their pathogenic role, although not demonstrated, can be strongly suspected, and, in a practical way, screening for the anti-Ig in kidney transplant recipients could be of value as a prognostic test.