The role of crude human saliva and purified salivary MUC5B and MUC7 mucins in the inhibition of Human Immunodeficiency Virus type 1 in an inhibition assay.
BACKGROUND
Despite the continuous shedding of HIV infected blood into the oral cavity and the detectable presence of the AIDS virus at a high frequency, human saliva is reported to inhibit oral transmission of HIV through kissing, dental treatment, biting, and aerosolization. The purpose of this study was to purify salivary MUC5B and MUC7 mucins from crude saliva and determine their anti-HIV-1 activities.


METHODS
Following Sepharose CL-4B column chromatography and caesium chloride isopycnic density-gradient ultra-centrifugation, the purity and identity of the mucins was determined by SDS-PAGE and Western blotting analysis respectively. Subsequently an HIV-1 inhibition assay was carried out to determine the anti-HIV-1 activity of the crude saliva and purified salivary mucins by incubating them with subtype D HIV-1 prior to infection of the CD4+ CEM SS cells.


RESULTS
Western blotting analysis confirmed that the mucin in the void volume is MUC5B and the mucin in the included volume is MUC7. The HIV inhibition assay revealed that both the crude saliva and salivary MUC5B and MUC7 mucins inhibited HIV-1 activity by 100%.


CONCLUSIONS
Although the mechanism of action is not clear the carbohydrate moieties of the salivary mucins may trap or aggregate the virus and prevent host cell entry.
Habte
Habtom H
HH
Department of Surgery, University of Cape Town, Cape Town, South Africa. hhabte@uctgsh1.uct.ac.za
Mall
Anwar S
AS
de Beer
Corena
C
Lotz
Zoë E
ZE
Kahn
Delawir
D
D000596:Amino Acids / Q000032:analysis; D019380:Anti-HIV Agents / Q000494:pharmacology*; D015153:Blotting, Western; D002850:Chromatography, Gel; D004591:Electrophoresis, Polyacrylamide Gel; D015497:HIV-1 / Q000145:classification / Q000187:drug effects* / Q000502:physiology; D006801:Humans; D055257:Mucin-5B; D009077:Mucins / Q000032:analysis / Q000302:isolation & purification / Q000494:pharmacology*; D012463:Saliva / Q000737:chemistry / Q000502:physiology*; D012471:Salivary Proteins and Peptides
D000596:Amino Acids; D019380:Anti-HIV Agents; C524578:MUC5B protein, human; C083238:MUC7 protein, human; D055257:Mucin-5B; D009077:Mucins; D012471:Salivary Proteins and Peptides