Seroconversion to human-cytomegalovirus-specific pre-early nuclear antigens in renal transplant recipients

Seroconversion to human cytomegalovirus (H-CMV)-specific antigens was observed in 8 out of 9 renal transplant recipients. In 7 of the 8 recipients antibody to "pre-early nuclear antigens" (PENA), which are detectable in human embryonic lung cells within 1 hr of H-CMV infection by anti-complement immunofluorescence staining, developed concomitantly with the increase in other antibodies including anti-early antigens (EA), anti-nuclear inclusions (NI), and complement-fixing (CF) antibody in 1--2 months after transplantation. About 1 year later, anti-PENA and anti-EA titers were concomitantly decreased in 2 recipients, whereas anti-NI and CF antibody titers were maintained at elevated levels in all the seroconverted recipients. These results support the idea that the development of antibody to PENA, like antibody to EA, may represent a current or recent infection with (or reactivation of) H-CMV. In one patient, antibody to PENA did not develop through the observation period despite increases in antibody to EA and other antibodies; this lends support to immunological distinctness of PENA from EA.