combined pretransplantation seropositivity of kidney transplant recipients for cytomegalovirus antigens [pp150 and pp28] a predictor for protection against infection?

ABSTRACT

This study was aimed at detecting antibodies to the antigens which may contribute to protection against cytomegalovirus [CMV] infection after organ transplantation. A total of 203 kidney transplant patients were enrolled in the study. Based on CMV antigenemia assay, 23 patients were antigen-positive and of the remaining 180 antigen-negative patients, 46 were selected as controls matched for age, gender and source of kidney. The 69 kidney recipients [KR] had CMV antibody due to previous infection and were followed up for a period of 6 months after transplantation for the development of active CMV infections by the antigenemia assay. Antibody responses to five CMV-related peptide antigens [pp65, gB, pp150, pp28 and pp38] were investigated by enzyme immunoassay and their presence was correlated with the results of the CMV antigenemia assay. Of the five CMV-related peptide antigens, only gB antigen showed response to the antibody in 10/23 [43.5%] antigen-positive patients and 9/46 antigen-negative patients and the difference was statistically significant [p = 0.048]. On the other hand, there was no significant difference in antibody responses between the antigen-positive and antigen-negative KR to the other four CMV peptide antigens [p > 0.05]. However, among the antigen-positive KR there was only 1 patient who had antibodies to both pp150 and pp28 antigen, while among the antigen-negative KR, 22 of 46 [47.8%] had the antibodies [p < 0.001]. The findings suggest that the combined presence of antibodies against the pp150 and pp28 antigens may indicate a lower risk of CMV reactivation after kidney transplantation