Scientists at the National Institute of Allergy and Infectious Diseases (NIAID) have found that treating mice with interleukin-12 (IL-12) plus conventional antibiotic therapy can help control infection with Mycobacterium avium, an opportunistic infection common in people with late-stage AIDS. IL-12, a cytokine or chemical messenger produced by immune cells, helps regulate cell-mediated immunity.
These findings in immunodeficient mice suggest that combined IL-12/drug treatment may offer a highly effective strategy for managing atypical mycobacterial infections in people who have AIDS or are otherwise immunocompromised, note Mark Doherty, Ph.D., and Alan Sher, Ph.D., of NIAID's Laboratory of Parasitic Diseases, in their report published June 1 in the The Journal of Immunology. Furthermore, they postulate that the same approach might work for other opportunistic infections common in these individuals such as Toxoplasma and Histoplasma. Previous research in animals has shown that these infections also respond to IL-12 treatment.
Based on the new findings, researchers at the National Institutes of Health led by Henry Masur, M.D., recently began recruiting people with both AIDS and Mycobacterium avium complex (MAC) into a Phase I clinical trial to test IL-12 in combination with standard antibiotic treatment regimens. MAC is an infection caused by either M. avium or its close relative, M. intracellulare.
"This is an excellent example of how a preclinical study can provide a model for designing a clinical trial," says Anthony S. Fauci, M.D., director of NIAID.
"It's very difficult to treat this infection in AIDS patients," comments Dr.
Sher. Often patients have to be treated with three or four different drugs,
which can have toxic side effects so that patients become intolerant to one or
more drugs. Furthermore, the bacteria that causes the infection can become
resistant to one or more antibiotics. This protocol is evaluating a way we
Contact: Laurie K. Doepel
NIH/National Institute of Allergy and Infectious Diseases