SalivarySLPI in Oral Candidiasis Among HIV-positive and At-Risk HIV-negative Women

BACKGROUND: Innate immunity helps to control the growth of oral pathogens by producing antimicrobial molecules. e.g. salivary secretory leukocyte protease inhibitor (salSLPI), a mucosal antiprotease with anti-inflammatory and wound healing activities. Oropharyngeal candidiasis (OC), typically caused by Candida albicans, is frequently found in HIV-infected persons. A role for salSLPI in OC has not been characterized.

OBJECTIVE: To determine whether salSLPI levels vary with OC diagnosis, HIV-serostatus and HIV-progression.

METHODS: Study participants were 91 women (66 HIV+, 25 HIV-) enrolled in the Oral Sub-Study at the Chicago and Los Angeles sites of the Women's InterAgency HIV Study (WIHS) who were free of OC at the baseline (BL) visit, had also participated in 1 (n=74) or 2 (n=24) consecutive 6-month follow-up (FU) visits, had complete data from interview questionnaires and oral examinations, and had reposited whole saliva for salSLPI measurement by ELISA. WIHS is the largest longitudinal cohort study of HIV infected and at-risk seronegative women in the US. Participant demographics, HIV status, CD4 cell count, viral load, smoking status, OC diagnosis, and salSLPI content were assessed for associations between salSLPI and OC, HIV status and HIV progression using t-tests (paired/unpaired) and ANOVA.

RESULTS: Overall, mean salSLPI levels for the HIV+ and HIV- groups were similar at BL (173.06±225.7 µg/mL vs 151.7±184.3 µg/mL), first FU (151.9±193.9 µg/mL vs 135.0±141.9 µg/mL) and second FU (208.2±240.8 µg/mL vs 112.0±107.7 µg/mL). Those with OC at 1stFU (n=27 HIV+) had significantly lower salSLPI levels than those without OC at 1stFU (102.7±104.7 µg/mL vs 170.3±206.3 µg/mL, p=0.01). The significant salSLPI-OC association was maintained after adjusting for CD4 count and smoking (p=0.01).

CONCLUSIONS: These data support a role for salSLPI in the oral mucosal defense against C. albicans. SalSLPI may serve as an indicator for OC infection among HIV-positive women.