ESTUDIO MICROBIOLÓGICO E INMUNOLÓGICO DE LA INFECCIÓN OCULAR

Abstract

The innate immunity is the first defense mechanism of a host, which limits an infection during the first hours of exposure to a pathogen. The TLR's and NOD's are innate immunity molecules present in immune cells and epithelial cells of various tissues. These molecules have molecular targets such as bacterial components: the lipopolsacárido (LPS), peptidoglycan (PNG), lipoteichoic acid (LTA), muramildepeptido (MDP), flagellin, and nucleic acid sequences oligonucleotides with cytosine-phospho-guanine (CPG). In previous works, the research group found that murine corneal fibroblasts stimulated with PNG induce expression of antimicrobial peptide CRAMP (homologue of human LL-37). It has also been observed that primary cultures of human limbal fibroblasts stimulated with LPS express VEGF but not the antimicrobial peptide LL-37. In the human keratinocyte cell line HaCaT was found that stimulation of those with PNG induces expression of LL-37 and VEGF. On the other hand, when i know about the LL-37 expressed in the cell line HaCaT was found that it modulates the expression of VEGF. Based on the above we decided to test whether the peptidoglycan, lipoteichoic acid and muramyl dipeptide induces the expression of any member of the family of vegf in primary cultures of human limbal fibroblasts. The PNG induced expression of VEGFA in a time response, and dose response with submitted to a maximum of expression from the lowest concentration of PNG and maintained this expression at all doses tested. The MDP the same form induced VEGFA expression dose and time response, the lipoteichoic acid did not change the level of expression of the VEGFA family in all assays tested.