@article{open325, volume = {28}, number = {1}, month = {May}, author = {S Majumdar and H Kaur and H Vohra and Grish C Varshney}, note = {Copyright of this article belongs to Elsevier/ Wiley}, title = {Membrane surface of Mycobacterium microti-infected macrophages antigenically differs from that of uninfected macrophages.}, publisher = {Elsevier Science}, year = {2000}, journal = {FEMS immunology and medical microbiology}, pages = {71--7}, keywords = {Macrophage; Surface membrane; Antigenic change; Mycobacterium microti}, url = {http://crdd.osdd.net/open/325/}, abstract = {Identification of the antigenic changes in mycobacteria-infected macrophage may be important in understanding the mechanisms responsible for the intracellular survival of the bacteria. In the present study, Mycobacterium microti-infected macrophages were utilized to investigate the possibility of differentiating the infected cells from normal cells, based on the antigenic changes occurring in the membranes. Antisera were generated against bacterial extract, heat-killed bacteria and crude preparation of M. microti-infected homologous macrophage membrane. The reactivity of these antisera, towards in vitro infected macrophages, was compared by flow cytometry. Unlike anti-bacterial extract antiserum or anti-heat-killed bacterial antiserum, anti-infected macrophage membrane antiserum reacted with infected macrophage surface. This reactivity increased with the increase in post-infection time. However, it was not observed with uninfected macrophages, PMA- or lipopolysaccharide-activated macrophages and those harboring Mycobacterium tuberculosis H37Ra, heat-killed M. microti and Leishmania donovani. Interestingly, anti-infected macrophage membrane antiserum identified a 63-kDa antigen in M. microti-infected macrophage membranes which was not present in the membranes of normal macrophages, activated macrophages and of those infected with M. tuberculosis H37Ra, heat-killed M. microti and L. donovani. Thus, membranes of M. microti-infected macrophages differ antigenically from those of the normal macrophages and infected homologous macrophage membrane antiserum provides a useful tool in studying such changes.} }