Interferon-gamma in endocervical secretions of women infected with Chlamydia trachomatis.

Although interferon-gamma has been associated with control of chlamydial infections in mice, no direct evidence links it to human chlamydial infections. Therefore, interferon-gamma was assayed by ELISA in endocervical secretions and plasma of women cultured for Chlamydia trachomatis. Women with positive endocervical chlamydial cultures had increased levels of interferon-gamma in endocervical secretions (6.7 +/- 2.8, mean +/- SE, n = 47) compared with uninfected women (1.4 +/- 0.4, n = 52) (P = .002). Interferon was also present in secretions of women with gonorrhea. Higher levels were seen in secretions from older women with positive chlamydial cultures. Interferon levels in secretions did not correlate with simultaneous plasma levels, the number of organisms recovered in tissue culture, or clinical correlates of inflammation. These data suggest that interferon-gamma is present at the site of chlamydial infection; however, further experiments are needed to determine whether interferon is specifically involved in protection or is a nonspecific indicator of inflammation.

Membrane fluidity alterations in a cytochrome P-450-deficient mutant of Candida albicans.

A cytochrome P450-deficient mutant of the pathogenic fungus, Candida albicans, which accumulates exclusively 14 alpha-methylsterols in place of the normal end product sterol, ergosterol, was examined for alterations in membrane fluidity by electron paramagnetic resonance. The results using four nitroxyl spin labels indicated that exponential phase cultures of the mutant strain, D10, had a uniformly more rigid membrane than similarly grown wild type. Since D10 shows a sterol spectrum similar to that of wild type cells treated with imidazole and triazole antifungal agents, many of the physiological effects reported as the result of azole application may be the result of alterations in membrane fluidity.