Estimation and Comparison of Salivary Secretory Leukocyte Protease Inhibitor in Human Immunodeficiency Virus Patients and Healthy Individuals

AIM: Transmission of human immunodeficiency virus (HIV) in the oral cavity is a rare event, despite detectable virus in saliva and oropharyngeal tissues of infected persons, unlike other mucosal sites. Secretory leukocyte protease inhibitor (SLPI) has been suggested as the main soluble factor responsible for the HIV inhibitory effect of saliva. The study was designed to estimate and compare the salivary SLPI levels in HIV patients and healthy controls. Furthermore, the relationship between salivary SLPI levels and disease severity was also investigated. MATERIALS AND METHODS: Unstimulated whole saliva specimens were collected from 60 HIV-infected and 20 healthy subjects. Disease severity was determined by CD4 count in HIV subjects, who were divided into two groups: ≥200 cells/μL (n = 30) and < 200 cells/μL n = 30. Salivary SLPI levels were determined by enzyme-linked immunosorbent assay. RESULTS: Numerically higher SLPI levels were observed in HIV subjects 193.342 ng/mL vs. 190.587 ng/mL; P = 0.517. A nonsignificant negative correlation was noted between CD4 counts and SLPI levels r = −0.037, P = 0.781. CONCLUSION: The salivary anti-HIV factor, SLPI, is not only preserved in HIV infection but its concentration may even get enhanced in the infection. However, the clinical significance of SLPI levels and disease severity should be investigated further with a larger sample of patients.