Article

MUC1 in human milk blocks transmission of human immunodeficiency virus from dendritic cells to T cells.

Department of Molecular Cell Biology and Immunology, VU University Medical Center, Amsterdam, The Netherlands.
Molecular Immunology (Impact Factor: 2.65). 05/2009; 46(11-12):2309-16. DOI: 10.1016/j.molimm.2009.03.025
Source: PubMed

ABSTRACT Mother-to-child transmission of human immunodeficiency virus-1 (HIV-1) occurs frequently via breast-feeding. HIV-1 targets DC-SIGN+ dendritic cells (DCs) in mucosal areas that allow efficient transmission of the virus to T cells. Here, we demonstrate that the epithelial mucin MUC1, abundant in milk, efficiently bound to DC-SIGN on DC. The O-linked glycans within the mucin domain contained Lewis X structures, that were specifically recognized by the receptor. Interestingly, MUC1 prevented DC-SIGN-mediated transmission of HIV-1 from DCs to CD4+ T cells. We hypothesize that repetitive units of Lewis X, within the mucin domain, play an important role in inhibiting transmission of HIV-1 from mother to child.

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