Work

Interferon-gamma and tumor necrosis factor-alpha exert their antirickettsial effect via induction of synthesis of nitric oxide.

Year: 1993

Type: article

Abstract: How the host defenses control rickettsiae in the cytosol of nonphagocytic host cells, where they are not exposed to antibodies or phagocytes, has posed a difficult question. Rickettsia conorii infection of a mouse fibroblast cell line was inhibited in a dose-dependent manner by nitrogen oxide synthesized by eukaryotic host cells stimulated by interferon-gamma or tumor necrosis factor-alpha. L-arginine was the source of the nitric oxide as demonstrated by competitive inhibition by NG-monomethyl-L-arginine. Nitric oxide synthesis required host cell protein synthesis and had an approximately 48-hour lag phase following cytokine stimulation. At low doses of interferon-gamma and tumor necrosis factor-alpha, which had no detectable response as single agents, dramatic synergistic nitric oxide synthesis and antirickettsial effects were observed.

Source: PubMed

Authors: H M Feng, D H Walker

Institution: The University of Texas Medical Branch at Galveston

Language: English

Topic: Vector-borne infectious diseases

Subfield: Parasitology

Field: Immunology and Microbiology

Domain: Life Sciences

SDG: Good health and well-being

Open Access status: green

Funder: National Institute of Allergy and Infectious Diseases

Award: Spotted Fever Rickettsial Antigens