Increased level of interferon-alpha in blood of patients with insulin-dependent diabetes mellitus: Relationship with coxsackievirus B infection

The activation of the interferon (IFN)-alpha system and its relationship wi th coxsackievirus B (CVB) infection has been analyzed in 56 patients with i nsulin-dependent diabetes mellitus (IDDM; 25 children and 31 adults). Eleva ted levels of IFN-alpha were found in plasma of 70% of patients (39/56), an d a positive detection of IFN-alpha mRNA in blood cells by reverse transcri ptase-polymerase chain reaction CRT-PCR) was observed in 75% of patients (4 2/56), Enterovirus (EV) RNA assayed by seminested RT-PCR was detected in th e blood of 50% of IFN-alpha-positive patients but not in any IFN-alpha-nega tive patients. The results of genotype analysis of amplified EV RNA sequenc es (5 CVB2, 8 CVB3, and 8 CVB4) were concordant with the results of CVB-neu tralization tests. The comparison between IFN-alpha, EV RNA, and serology s uggested that the proportion of CVB infection associated with IFN-alpha pos itivity might be higher than is predicted from the investigation of EV RNA, Together, the results suggest that, in a majority of cases, a CVB infectio n is associated with clinical IDDM.