Cell-to-Cell HIV Transmission
Combating Cell-to-Cell HIV Transmission
HIV viruses can spread in different ways. Some spread from one cell to another through plasma called cell-free transmission, and others spread directly between cells, or cell-to-cell. A recent study tested the ability of antiretroviral drugs to prevent cell-to-cell HIV transmission, which produced very valuable information in regards to how antiretroviral therapies (ARTs) are so effective and how to avoid the virus becoming resistant to the medications.
Researchers at a prominent American university came up with a way to examine the difference between cell-free and cell-to-cell HIV transmission. They went through and tested different types of HIV treatments to see how well they treated both types of virus transmission. These tests included non-nucleoside reverse transcriptase inhibitors (NNRTIs), nucleoside reverse transcriptase inhibitors (NRTIs), protease inhibitors (PIs), and entry inhibitors (ENT-Is), also called fusion inhibitors. The tests proved that all types of medication, with the exception of NRTIs, were very effective in treating cell-to-cell spread of the virus.
During these experiments, scientists also tested how these drugs react when treating cell-free transmission. When they added more viruses to a certain area of cells, raising the multiplicity of infection (MOI), they found that the drugs reacted much like they did when treating cell-to-cell transmission. In this instance, as in the one before, NRTIs did not do well in fighting the virus. Because there were a higher number of infected cells, the quantity of the drug necessary to combat it was also higher. The drugs were also more effective when combined, proving that combined ARTs are some of the most useful for suppressing HIV. No matter what a patient is prescribed, however, it is important that they take their medicine as ordered to avoid the cells becoming drug- resistant. In addition, for an HIV drug to be most effective, they must be able to handle a high MOI—that is, a high ratio of infectious cells to target cells—to effectively combat cell-to-cell HIV transmission.