Tissue polypeptide specific antigen for the detection of lymphoproliferative diseases induced by cyclosporine

Abstract

Aim-To evaluate the efficacy of tissue polypeptide specific (TPS) antigen for the early detection of cyclosporin A (CyA) induced post-transplant lymphoproliferative diseases. Methods-Serum concentrations of TPS antigen were analysed using a monoclonal enzyme immunoassay and whole blood CyA concentrations were measured using high pressure liquid chromatography. Infection with Epstein-Barr virus and cytomegalovirus was detected by determiniing levels of IgM and IgG antibodies directed against viral capsid antigen (VCA). Immunohistochemistry and analysis of clonality were carried out on formalin fixed, paraffin wax embedded tissue. Results-The mean serum concentration of TPS antigen in the eight transplant recipients investigated was 60 UnI during periods without complication (control), 101 UnI during infection, 166 Un1 when the diagnosis of a lymphoma was confirmed, and 172 Unl when lymphoma and infection coincided. Increased TPS antigen concentrations were detected in six patients one month before detection ofmalignancy. After reduction of immunosuppression and the start of tumour regression, TPS antigen concentrations decreased. TPS antigen concentrations increased in the one patient who experienced a recurrence. Conclusions-Continuous monitoring of TPS antigen concentrations leads to the early discovery of CyA induced lymphoprolilferative disease.