Discovery Of New Type of Immune Cells,CD11c+, Leads To New HIV Treatment Strategy
New immunity cells known as CD11c+ dendritic cells have been identified by a team of researchers from The Westmead Institute For Medical Research in Sydney.These CD11c+ dendritic cells are extremely susceptible to the HIV virus and can transmit the virus to other cells especially the CD4 T Cells.
These CD11c+ dendritic cells are a type of dendritic cells that play a role in capturing any incoming disease causing virus or bacteria (pathogens) and then deliver them to the CD4 T cells. These CD11c+ cells are only only found in human genital tissues, especially at the epithelial levels of the vagina, inner penile foreskin and anus, indicating that these CD11c+ dendritic cells are the first immune cells to interact with HIV virus.
"CD4 T cells drive an immune response to the pathogen but at the same time are also the primary HIV target cells in which the virus replicates.When dendritic cells capture a pathogen, they communicate what they have found to CD4 T cells in the lymph nodes, essentially giving the immune system a constant relay of ‘information’. This prepares the immune system to either tolerate a bacteria or virus, or attack it. However, if CD4 T cells fall below critical levels (e.g. in HIV positive patients), then the body is no longer able to mount an immune response, leading to a diagnosis of AIDS.The newly discovered CD11c+ dendritic cells are more vulnerable to HIV virus than any other known dendritic cell and interact with CD4 T cells more efficiently than any other dendritic cells These CD11c+ dendritic cells transfer the virus to CD4 T cells, making them key drivers of HIV infection. As these dendritic cells are so efficient at interacting with CD4 T cells, they are also important vaccine candidates.” said lead researcher,Associate Professor Andrew Harman in an exclusive interview with Thailand Medical News.
Using new RNAscope technology. the research team was able to observe ,only after 30 minutes after donated genital tissues were surgically removed from the body, how living CD11+c dendritic cells took up the virus and delivered it to the CD4 T cells.
This finding opens up a potential for the development of strategies to block the transmission of HIV by blocking HIV's ability to bind to the CD11+c dendritic cells, which are the first immune cells to encounter the HIV virus. Also another strategy to be looked into is to how to block the CD11c+ cells ability to transmit the virus to the CD4T cells.
Both these strategies could help in a situation where there are low levels of CD4 T cells, thus helping to stop the virus from spreading. This new information can also be used to develop a HIV vaccine. If HIV fragments or inactivated HIV were targeted at these CD11+c dendritic cells, this would have the potential to prime an immune response against HIV immediately as it enters the body.
Reference: Kirstie M. Bertram et al, Identification of HIV transmitting CD11c+ human epidermal dendritic cells, Nature Communications (2019). DOI: 10.1038/s41467-019-10697-w