Cytokines enhance neutrophils from human immunodeficiency virus-negative donors and AIDS patients to inhibit the growth of Mycobacterium avium in vitro

Mycobacterium avium is one of the most prevalent opportunistic infections in AIDS patients, and neither prophylaxis nor treatment against M, avium is effective. To evaluate host defense mechanisms against mycobacterial infections, studies investigated whether neutrophils from AIDS patients could inhibit the growth of M, avium in vitro and what cytokines enhance neutrophil function against M, avium. Peripheral blood neutrophils from human immunodeficiency virus-negative and AIDS patients were incubated with media, granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin-8, or macrophage-inhibitory proteins and infected with M, avium, and the inhibition of bacterial growth was determined. G-CSF (1000 U/mL) and GM-CSF (2000 U/mL) stimulated neutrophils from AIDS patients to significantly inhibit M, avium growth. These results demonstrate that neutrophils from AIDS patients can respond to exogenously supplied G-CSF or GM-CSF by inhibiting the growth of M. avium.