Expression profile of porcine scavenger receptor A and its role in bacterial phagocytosis by macrophages.

Expression of scavenger receptor A (SRA) in macrophages plays key role in macrophage mediated uptake of microbes. However, little is known about the role of porcine scavenger receptor A (pSRA) in phagocytic function of macrophages in swine species. In this study, polyclonal antibody against pSRA was generated by using recombinant proteins to study expression and function of pSRA. We report broad expression of pSRA in different tissues. In the lungs, pSRA is mainly expressed by alveolar macrophages. Blockade of class A scavenger receptor by fucoidan treatment demonstrates that pSRA has role in bacterial phagocytosis by macrophages. Furthermore, importance of SRA-mediated bacterial phagocytosis has been shown using CHO cell line expressing pSRA. In summary, these findings reveal that pSRA, which is predominantly expressed in alveolar macrophages is likely to be an important receptor mediating recognition and uptake of bacteria in pig lungs.

Pubmed ID: 31689452