Human submandibular saliva specifically inhibits HIV type 1

Area of Science:

• Immunology
• Virology
• Biochemistry

Background:

• Human saliva contains factors with in vitro anti-HIV-1 activity.
• Previous studies indicated higher anti-HIV-1 activity in submandibular saliva compared to parotid or whole saliva.
• Individual variations in anti-HIV activity were noted, necessitating further investigation.

Purpose of the Study:

• To investigate the anti-HIV-1 inhibitory activity of individual human submandibular saliva samples.
• To assess the impact of filtration on HIV-1 inhibitory activity in submandibular saliva.
• To evaluate the activity of submandibular saliva against laboratory and clinical isolates of HIV-1, HIV-2, and SIV.

Main Methods:

• Collected individual submandibular saliva samples from 15 donors.
• Assessed HIV-1 inhibitory activity in vitro, with and without a filtration step.
• Tested activity against laboratory strains and clinical isolates of HIV-1, HIV-2, and SIV.

Main Results:

• Significant variations in anti-HIV-1 activity were observed among individual saliva samples (9/15 similar, 4/15 less active, 2/15 inactive).
• Filtration generally did not alter activity, but 2 samples showed activity only after filtration.
• Submandibular saliva demonstrated activity against HIV-1 laboratory strains and clinical isolates, but not against HIV-2 or SIV.

Conclusions:

• Individual differences in submandibular saliva composition influence its anti-HIV-1 activity.
• Filtration can be important for detecting inhibitory factors in some individuals.
• Submandibular saliva's anti-HIV-1 activity is relevant against diverse HIV-1 strains, but not other related viruses.