Proteomic profiling of macrophages infected with Penicillium marneffei

Abstract

Penicillium marneffei is a pathogenic fungus with the unique characteristic of dimorphism. When grown at 25°C, it grows in the mold phase, while at 37°C it takes on characteristic of a yeast. Humans can be infected with this fungus if conidia (mold spores) are inhaled. Once inside the body, P. marneffei undergoes a phase change to form yeast-like cells. It is this phase transition that accounts for the pathogenic effect on the body. Active macrophages are capable of carrying out phagocytosis of foreign entities in the body and initiating an immune response to destroy them. Penicillium marneffei is one such pathogen that macrophages are known to attack. Conceivably, the proteins produced by marcrophages may differ depending on whether or not they have phagocytized a foreign molecule. The purpose of my study was to compare the proteins produced by macrophages infected with the fungus Penicillium marneffei to those not infected with the fungus. This objective was achieved by growing and collecting the conidia of P. marneffei, adding them to a solution containing live murine macrophages, and allowing for phagocytosis to occur. The proteins were then isolated from both infected and control macrophages and were visualized with the aid of 2-dimensional gel electrophoresis. This technique provided spot "maps" of the proteins present, which were then be compared and contrasted. Proteins of interest are those found in only one group of macrophages (infected or control). Further studies may include excision of these spots and sequencing in order to identify the proteins.