One of the reasons why we still do not have a definitive cure for HIV (human immunodeficiency virus) is that it infects the cells of the immune system responsible for activating the response that should stop the infection. Specifically, HIV has as its main target white blood cells called CD4 T lymphocytes, which receive this name because they have the CD4 protein in their membrane. The more than 20 drugs available on the market today work by blocking the cycle that HIV follows to infect these CD4 T lymphocytes, but they do not cure because they cannot completely eliminate the virus from the body. One of the reasons is that the available medication does not act on the callsdendritic cells, into which HIV also penetrates and most accumulates intact inside.
Spanish scientists from the IrsiCaixa AIDS Research Institute could remedy it after having found the entry point of HIV to these dendritic cells, an enigma that the scientific community has been trying to decipher for years. It’s about thesiglec-1 molecule, and allows HIV to access mature dendritic cells when the virus gangliosides bind, which function as keys. In this way, dendritic cells accumulate a large amount of virus inside them and become Trojan horses, favoring the infection of CD4 + T lymphocytes, the main target of HIV and thus contributing to the spread of HIV within the body.
The finding constitutes the latest great achievement of a line of research led by ICREA research professor from IrsiCaixa Javier Martínez-Picado and IrsiCaixa researcher Nuria Izquierdo-Useros, in collaboration with a research group from the University of Heidelberg, in Germany , coordinated by Professor Hans-Georg Kräusslich, and another from the University of Lausanne, in Switzerland, headed by Amalio Telenti. As a result of this line of work, last April they published an article in the same journal, where they identified a molecule called ganglioside that is found on the surface of HIV and is responsible for its entry into dendritic cells. As the researcher Javier Martínez-Picado explains, “we had the key and now we have found the lock.” “The enigma is solved: we are already working on the development of a drug that blocks this process and that allows improving the effectiveness of current treatments against AIDS,” he adds.
Furthermore, according to the researcher Nuria Izquierdo-Useros, it has been observed “thatthe protein that acts as a lock for the entry of HIV could also facilitate the entry of other virusesand therefore the finding could also lead to the development of treatments for other infections that use this same route of spread. “
