Existing efforts to short-circuit the HIV virus once it has successfully colonized human host cells, have consistently run aground. The rapid mutation and prolific reproduction of the virus combine with sophisticated strategies to evade host immune detection by any healthy cells remaining to combat the viral assault.
The new approach under investigation is a preventive vaccine against HIV that would arm the immune system, preparing it to kill infected cells, should the recipient encounter HIV following vaccination. The strategy relies on the fact that human cells affected by HIV infection manufacture aberrant proteins, which are not produced at significant levels by normal cells.
Specific cell proteins associated with HIV-infected cells will be rigorously tested for their ability to target and kill HIV-infected cells. Once identified, these proteins could be used as the basis for a vaccine to prevent AIDS. Because this approach borrows from a process Biodesign has applied to cancer cells, (which also generate specific, aberrant proteins), the infrastructure for its execution is in place.
Although vaccines employing components of a given pathogen have been applied with impressive results to a range of lethal diseases, the approach has thus far met with dispiriting failure in the case of HIV and may simply provide an inadequate weapon for this unusual pathogen.
Preventing HIV Backward relies on a two-pronged approach in which aberrant, host-encoded proteins consistently produced by HIV-infected cells are first identified and catalogued and then tested for their ability to kill infected cells while leaving healthy cells unaffected.
Curiously, the body seems unable to use this tactic to naturally combat HIV. The team believes the reason for this is that the immune system’s reaction to aberrant cell proteins is switched off by T-regulatory cells. This mechanism seems to also play a role in halting the body’s response to aberrant proteins produced by cancerous tumor cells. If the proteins are used as a vaccine however, the hope is that the immune system will be exposed to a sufficient quantity to mount a robust immune response. The efficacy of this approach for cancer vaccination has been demonstrated in mice. In the case of HIV, such a vaccine could gain a critical advantage over the virus, particularly if a method to specifically suppress T-regulatory cells can be developed.
Each month, innovative research from the Biodesign Institute appears in the world’s premier scientific journals. Many such studies have graced the covers of these journals, showcasing Biodesign research ranging from water remediation to nanometer-scale structures built from DNA.
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