Despite the presence of HIV-1 in the oral cavity, transmission of the virus through saliva has not been proven. Consistent with these observations, we recently identified an endogenous 12kD protein, secretory leukocyte protease inhibitor (SLPI), in saliva which blocks HIV-1 infection in vitro. Whereas other salivary proteins tested were inactive, purified native or recombinant SLPI inhibited HIV-1 infection of human monocytes at 100ng/ml. Levels of SLPI quantitated by ELISA in saliva from control and HIV-1 infected individuals exceeded this level, consistent with antiviral activity. As in saliva, levels of SLPI mRNA determined by Northern hybridization and protein as assessed by immunohistochemistry in the salivary glands of control and infected populations were comparable. In contrast to adults, oral transmission occurs in infants, possibly due to their lack of fully developed salivary glands. To determine whether the inadequate antiviral protection might be compensated for by maternal sources, we evaluated breast milk samples obtained 6 months postpartum. Levels of SLPI were significantly lower than in saliva and not sufficient to provide antiviral protection in contrast to colostrum samples in which SLPI levels were equivalent to those in saliva and able to inhibit HIV-1 infection when tested in vitro. These data suggest that breast milk may provide transient antiviral activity in the newborn, but that this maternal source of SLPI is of insufficient duration to maintain protection against mucosal transmission of the virus over time. The high functional levels of SLPI in saliva and the low levels in mature breast milk correlate with negligible rates of HIV-1 transmission by saliva and higher rates by breast feeding. In additional studies, the regulation of HIV replication through NF-kB as influenced by corticosteroids and interferon is being explored. Moreover, enhanced NF-kB expression may contribute to the ability of opportunistic pathogens to induce massive viral replication in macrophages even after CD4 depletion has occurred. Thus, macrophages may be a primary source of viremia in late stage HIV disease.

Agency
National Institute of Health (NIH)
Institute
National Institute of Dental & Craniofacial Research (NIDCR)
Type
Intramural Research (Z01)
Project #
1Z01DE000513-07
Application #
2572344
Study Section
Special Emphasis Panel (LI)
Project Start
Project End
Budget Start
Budget End
Support Year
7
Fiscal Year
1996
Total Cost
Indirect Cost
Name
National Institute of Dental & Craniofacial Research
Department
Type
DUNS #
City
State
Country
United States
Zip Code
Greenwell-Wild, Teresa; Vazquez, Nancy; Jin, Wenwen et al. (2009) Interleukin-27 inhibition of HIV-1 involves an intermediate induction of type I interferon. Blood 114:1864-74
Mavragani, Clio P; Niewold, Timothy B; Moutsopoulos, Niki M et al. (2007) Augmented interferon-alpha pathway activation in patients with Sjogren's syndrome treated with etanercept. Arthritis Rheum 56:3995-4004
Peng, Gang; Greenwell-Wild, Teresa; Nares, Salvador et al. (2007) Myeloid differentiation and susceptibility to HIV-1 are linked to APOBEC3 expression. Blood 110:393-400
Moutsopoulos, Niki M; Nares, Salvador; Nikitakis, Nikolaos et al. (2007) Tonsil epithelial factors may influence oropharyngeal human immunodeficiency virus transmission. Am J Pathol 171:571-9
Peng, Gang; Lei, Ke Jian; Jin, Wenwen et al. (2006) Induction of APOBEC3 family proteins, a defensive maneuver underlying interferon-induced anti-HIV-1 activity. J Exp Med 203:41-6
Moutsopoulos, N M; Greenwell-Wild, T; Wahl, S M (2006) Differential mucosal susceptibility in HIV-1 transmission and infection. Adv Dent Res 19:52-6
Vazquez, Nancy; Greenwell-Wild, Teresa; Rekka, Sofia et al. (2006) Mycobacterium avium-induced SOCS contributes to resistance to IFN-gamma-mediated mycobactericidal activity in human macrophages. J Leukoc Biol 80:1136-44
Wahl, Sharon M; Greenwell-Wild, Teresa; Vazquez, Nancy (2006) HIV accomplices and adversaries in macrophage infection. J Leukoc Biol 80:973-83
Riley, E M; Wahl, S; Perkins, D J et al. (2006) Regulating immunity to malaria. Parasite Immunol 28:35-49
Moutsopoulos, Niki M; Vazquez, Nancy; Greenwell-Wild, Teresa et al. (2006) Regulation of the tonsil cytokine milieu favors HIV susceptibility. J Leukoc Biol 80:1145-55

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