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Seminar

Tuesday, June 6th, 2023
11h30
Centre de recherche - Paris - Amphithéâtre Hélène Martel-Massignac (BDD)

Definitional and characterisation of human tissue mononuclear phagocytes and their role in HIV transmission

Mononuclear phagocytes (MNP) consist of Langerhans cells, macrophages and dendritic cells (DC). They can become infected by HIV and transport the virus to its primary target cells (CD4 T cells) in association with their antigen presenting cell function. 

We have revealed that the MNPs within anogenital tissues significantly differ to those in other parts of the body and we have defined three that preferentially transmit HIV; (i) epithelial cDC2, (ii) lamina propria langerin+ cDC2 and CD14+ monocyte derived DCs. We have also shown HIV causes MNP to form clusters with T cells within 2 hours of topical application and that the virus preferentially localises to DCs. Furthermore, DCs traffic HIV to lymphoid follicles which provide a conduit for the virus to enter the submucosa where it preferentially interacts with macrophages. 

These observations significantly advance our understanding of HIV transmission by (i) defining the specific MNPs that capture and transmit HIV (ii) demonstrating that transfer of HIV by MNPs to CD4 T cells occurs within mucosal tissue within 2 hours (rather than lymph nodes) and (iii) that HIV is actively trafficked between mucosal tissue compartments. This is essential information for vaccine design and adds important data regarding early seeding of the viral reservoir.

Speaker(s)

Andrew Harman
Professor of Virology and Immunology - Deputy Director of Centre for Virus Research, The Westmead Institute for Medical Research

School of Medical Sciences at the University of Sydney

Invited by

Elodie Segura

Institut Curie

Philippe Benaroch

Institut Curie

Contact

Sylvia Trival

Send an e-mail

To sum up

Andrew Harman is Professor of Virology and Immunology in the School of Medical Sciences at the University of Sydney where he co-leads the theme of Infection, Immunity and Inflammation. He is also the Deputy Director of the Centre for Virus Research at the Westmead Institute for Medical Research. 

Andrew has been working at the Westhead Health Precinct since completing his PhD at the University of Cambridge in 2002. This is the largest health precinct in the Southern Hemisphere comprising of 6 hospitals and two independent medical research institutes. He has extensive collaborations with surgeons across the precinct who provide his research group with a large range of human tissues discarded from surgery with which he conducts all his research.

He leads two research groups at the Westmead Institute for Medical Research, which investigate the role of mononuclear phagocytes in viral transmission and Inflammatory Bowel Disease.