Researchers at the UA BIO5 institute recently isolated and identified the protein that causes the tissue damage when a brown recluse bites an animal. When introduced into tissue, the protein cleaves off the head of the lipids in the cell membrane. Up until now, scientists thought that the reaction ended with the headless lipid being vulnerable to break down from the venom. Instead, we know that the protein actually causes the lipids to form cyclical structures. Many other insect bites create the same headless lipid structure, which very rarely in other insect bites causes systemic reactions. This discrepancy between other insect bites and brown recluse bites and their respective effects was one of the sources of inspiration for this study. When the ring structure forms, it initiates an immune response. This immune response is "basically our tissues committing suicide". The cells in the tissues begin to lose blood flow and begin to die, which stops the blood containing the venomous toxin from entering healthy tissues. If we have better understanding of the function of the cyclical structure that forms in the lipid tissue after a brown recluse bite, we could potentially develop an anti-venom to inhibit the protein and stop tissue damage or systemic reaction.
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