Harmful Effect of Anti-Class II Antibodies in Kidney Transplant Patients who Experienced an Acute Rejection Episode

The presence of anti-lymphocytes antibodies is associated with the occurrence of acute rejection after kidney transplantation but few is known on their role after the rejection episode. We conducted a retrospective study in kidney transplant recipients who experienced a biopsy proven acute rejection episode to analyse the influence of anti-lymphocytes antibodies on clinical outcome. Anti-lymphocytes antibodies were detected before and after transplantation and characterized for isotype, class I and class II targets and donor specificity. 76 kidney recipients were included and analysed for steroid resistance of acute rejection, serum creatinine and 1-year actual graft survival. The presence of anti-lymphocytes antibodies was noticed in 80% of patients. Anti-lymphocytes antibodies were associated with more frequent steroid resistant rejection episodes, higher creatinine at discharge and throughout the first year post transplantation and with a worse graft survival, at the condition they were of the IgG isotype, donor-specific, and they recognized class II targets. We conclude that donor-specific anti-class II IgG antibodies are deleterious in the subgroup of kidney transplant recipients who develope an acute rejection.