Many therapeutic compounds need to reach the inner space of cells to access their targets. For this reason, multiple strategies have been designed to break through the cells membranes with variable success outcomes. At the end of the 1980s, Frankel and Pabo published the unexpected finding of a protein that could penetrate cell membranes on its own. This was attributed to a short amino acid sequence in the TAT protein from HIV virus, capable of dragging large molecules such as proteins and nucleic acids across the cell membrane.
Researchers from the IBR applied this nature strategy to incorporate two proteins from a pathogenic bacteria into human neuronal cells. These Leptospira interrogans proteins are involved in efficient heme turnover and are likely to confer cell protection against oxidative stress injury.
Protein import to neuronal cells in culture through this system did not present cytotoxic effects. Furthermore, neurons treated with these proteins manage to limit the accumulation of reactive oxygen species, noxious chemical molecules that threaten cells survival, enhancing their tolerance to oxidative stress and hence, showing superior survival rates.
As described in this work, this novel biotechnological tool shows promising results in the prevention of oxidative stress induced neuronal damage. This approach might protect organs or tissues during transplants, trauma or ischemia. Moreover, exogenous imported proteins are eventually degraded by the cell's machinery, leaving no trace of them when no longer needed.