Activated mouse T-cells synthesize MHC class II, process, and present morbillivirus nucleocapsid protein to primed T-cells.
A pivotal step in the initiation of T-cell immunity is the presentation of antigenic peptides by major histocompatibility complex (MHC) expressed on antigen presenting cells. The expression of MHC class II molecules by mouse T-cells has not been shown unequivocally. In the present work, we demonstrate that activated mouse T-cells synthesize MHC class II molecules de novo and express them on their surface. Further, we have demonstrated that in vitro activated T-cells take up extra-cellular soluble nucleocapsid protein of a morbillivirus. The internalized antigen goes to antigen processing compartment as shown by co-localization of antigen and LAMP-1 using confocal microscopy. We show that activated T-cells express H2M, a chaperone molecule known to have a role in antigen presentation. Further, we demonstrate that activated T-cells process and present internalized extra-cellular antigen to primed T-cells as shown by IL-2 secretion and in vitro proliferation. The presentation of antigen by T-cells may have implications in immuno-regulation, control of infection by lymphotropic viruses and maintenance of immunological memory.
Lal
Girdhari
G
Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India.
Shaila
M S
MS
Nayak
Rabindranath
R
D000818:Animals; D017951:Antigen Presentation; D015703:Antigens, CD / Q000378:metabolism; D005802:Genes, MHC Class II; D006801:Humans; D008213:Lymphocyte Activation; D051907:Lysosomal Membrane Proteins; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D018103:Morbillivirus / Q000276:immunology*; D019590:Nucleocapsid Proteins / Q000276:immunology*; D012333:RNA, Messenger / Q000378:metabolism; D016176:T-Lymphocyte Subsets; D013601:T-Lymphocytes / Q000276:immunology*
D015703:Antigens, CD; D051907:Lysosomal Membrane Proteins; D019590:Nucleocapsid Proteins; D012333:RNA, Messenger