Transcytosis of HTLV-1 across a tight human epithelial barrier and infection of subepithelial dendritic cells

• Published in: Blood Vol. 120; no. 3; pp. 572 - 580
• Main Authors: Martin-Latil, Sandra, Gnädig, Nina F., Mallet, Adeline, Desdouits, Marion, Guivel-Benhassine, Florence, Jeannin, Patricia, Prevost, Marie-Christine, Schwartz, Olivier, Gessain, Antoine, Ozden, Simona, Ceccaldi, Pierre-Emmanuel
• Format: Journal Article
• Language: English
• Published: Washington, DC Elsevier Inc 19.07.2012; Americain Society of Hematology; American Society of Hematology
• Subjects: Biological and medical sciences; Caco-2 Cells; Coculture Techniques; Dendritic Cells - cytology; Dendritic Cells - metabolism; Dendritic Cells - virology; Enterocytes - cytology; Enterocytes - metabolism; Enterocytes - virology; Epithelial Cells - cytology; Epithelial Cells - metabolism; Epithelial Cells - virology; HEK293 Cells; Hematologic and hematopoietic diseases; HT29 Cells; HTLV-I Infections - metabolism; HTLV-I Infections - transmission; HTLV-I Infections - virology; Human T-lymphotropic virus 1 - metabolism; Humans; Life Sciences; Medical sciences; Microscopy, Electron, Transmission; T-Lymphocytes - cytology; T-Lymphocytes - metabolism; T-Lymphocytes - virology; Tight Junctions - metabolism; Tight Junctions - ultrastructure; Tight Junctions - virology; Transcytosis - physiology; Virion - metabolism; Virus; Human; Infection; Dendritic cell; Deltaretrovirus; Hematology; Antigen presenting cell; Subepithelial cell; Retroviridae; Transcytosis; HTLV-I virus
• ISSN: 0006-4971; 1528-0020
• DOI: 10.1182/blood-2011-08-374637

Human T-cell leukemia virus type 1 (HTLV-1) is the causative agent of adult T-cell leukemia/lymphoma and HTLV-1–associated myelopathy/tropical spastic paraparesis. In addition to blood transfusion and sexual transmission, HTLV-1 is transmitted mainly through prolonged breastfeeding, and such infection represents a major risk for the development of adult T-cell leukemia/lymphoma. Although HTLV-1–infected lymphocytes can be retrieved from maternal milk, the mechanisms of HTLV-1 transmission through the digestive tract remain unknown. In the present study, we assessed HTLV-1 transport across the epithelial barrier using an in vitro model. Our results show that the integrity of the epithelial barrier was maintained during coculture with HTLV-1–infected lymphocytes, because neither morphological nor functional alterations of the cell monolayer were observed. Enterocytes were not susceptible to HTLV-1 infection, but free infectious HTLV-1 virions could cross the epithelial barrier via a transcytosis mechanism. Such virions were able to infect productively human dendritic cells located beneath the epithelial barrier. Our data indicate that HTLV-1 crosses the tight epithelial barrier without disruption or infection of the epithelium to further infect target cells such as dendritic cells. The present study provides the first data pertaining to the mode of HTLV-1 transport across a tight epithelial barrier, as can occur during mother-to-child HTLV-1 transmission during breastfeeding.