Specific IgE detected by ELISA and immunoblot after human cytomegalovirus infection (HCMV) in renal transplant (RT) recipients.

BACKGROUND: Specific HCMV IgE response has been reported by some authors, and was proposed as a valuable virologic marker of CMV infection. OBJECTIVES: we evaluated specific HCMV IgE in renal transplant patients with active (primary and secondary) HCMV infection with special interest to symptomatic infections. STUDY DESIGN: Specific IgE was tested retrospectively by ELISA and immunoblot (IB) on sera of 55 RT patients who were followed before and after transplantation with virologic markers of CMV infection. RESULTS: Total serum IgE levels were similar in control group and in patients with primary and secondary HCMV infections. Anti-CMV specific IgE response by ELISA was more frequently found in patients with primary infection (76.9%) than in patients with secondary infection (47.1%). These specific IgE reacted on immunoblot with a 150 kDa protein in 84.6% of patients with primary infection and 94.1% with secondary infections; and reacted with rp52 (pUL44) in 76.9% of primary infection and 47.1% of secondary infection. CONCLUSIONS: Anti-CMV specific IgE tested by immunoblot and ELISA is a marker of CMV infection. It was clearly detected in cases of active infection (primary and secondary) and was present in cases with severe CMV clinical manifestations. In contrast, anti-CMV specific IgE, was consistently negative among healthy blood donors. This is the first report of CMV proteins detected by IgE immunoblot.