Effect of Apheresis for ABO and HLA Desensitization on Anti-Measles Antibody Titers in Renal Transplantation

Abstract

Desensitization strategies for ABO-incompatible renal transplants with plasma exchange (PE) or specific immunoadsorption (IA) decrease immunoglobulin levels. After recent measles outbreak and decreasing vaccination rates, we studied the impact of apheresis on anti-measles antibodies. Anti-measles antibodies were measured before desensitization, before transplantation and during followup in 12 patients with ABO incompatibility (2x PE only, 8x IA only, and 2x IA and PE) and 3 patients with donor-specific HLA antibodies (all PE). Patients received rituximab, IVIG, and standard immunosuppressive therapy. All patients had detectable anti-measles antibodies before desensitization (mean 3238 mU/l, range 560-8100). After 3-6 PE sessions, titers decreased significantly to 1710 mU/l (P < 0.05), in one patient to nondetectable values, while IA only maintained protective titers. After a median followup of 64 days, anti-measles antibodies returned to baseline in all patients. Immunity against measles was temporarily reduced by apheresis but remained detectable in most patients at time of transplantation. Desensitization maintains long-term protective immunity against measles.

Figure 1

Effect of apheresis on reduction of anti-measles IgG antibodies. Antibody titer reduction (in %) at time of transplantation in comparison to the baseline values among patients using plasma exchange either alone or in combination with antigen-specific immunoadsorption (n = 7) or antigen-specific immunoadsorption alone (n = 8). There was a mean reduction of 40% in the plasma exchange group.

Figure 2

Effect of desensitization therapy on anti-measles IgG antibody titers (mU/l). Anti-measles antibodies were measured before desensitization therapy (“before”), the day before transplantation (“tx”) and during followup (“after”). Patients were analysed according to the used apheresis strategies: use of plasma exchange either alone or in combination with antigen-specific immunoadsorption (n = 7) or antigen-specific immunoadsorption alone (n = 8). At the time of transplantation, antibody titers were significantly reduced in the plasma exchange group compared to baseline (P < 0.05).