Opportunistic Infections Associated With Antibodies to IFN
(HealthDay News) – Neutralizing anti-interferon-γ autoantibodies are detected in most Asian adults with multiple opportunistic infections.
Sarah K. Browne, MD, from the National Institute of Allergy and Infectious Diseases in Bethesda, MD, and colleagues examined the role of autoantibodies against interferon-γ in patients with severe disseminated opportunistic infection. A cohort of 203 individuals in five groups from sites in Thailand and Taiwan were enrolled. Clinical histories were recorded and blood specimens obtained for 52 patients with disseminated, nontuberculous mycobacterial infection (group 1); 45 patients with a different opportunistic infection, with or without nontuberculous mycobacterial infection (group 2); nine patients with disseminated tuberculosis (group 3); 49 patients with pulmonary tuberculosis (group 4); and 48 healthy controls (group 5).
The researchers found that CD4+ T-cell counts in patients in groups 1 and 2 were similar to those of groups 4 and 5, and the patients were not infected with HIV. Patients in groups 1 and 2 had intact cytokine production and response to cytokine stimulation when cells were washed, but the plasma from these patients inhibited interferon-γ in normal cells. High-titer anti-interferon-γ autoantibodies were detected in most patients in groups 1 and 2 (81 and 96%, respectively), but in few patients from groups 3, 4, and 5 (11, 2, and 2%, respectively).
"In conclusion, our study showed that this adult-onset immunodeficiency syndrome is strongly associated with high-titer neutralizing antibodies to interferon-γ, supporting the central role of interferon-γ in the control of numerous pathogens," the authors write.
One author disclosed financial ties to several pharmaceutical companies.