Subset-specific analysis of calcium fluxes in murine AIDS.
Infection of susceptible strains of mice with the Duplan strain of murine leukemia viruses induces a syndrome called MAIDS (murine acquired immunodeficiency syndrome) characterized by immunodeficiency and lymphoproliferation. In addition to a complete refractoriness of most subsets of lymphocytes to mitogen stimulation, the development of phenotypic abnormalities occurs such as the appearance of an abnormal CD4+ T cell subset lacking membranes Thy-1. This study was performed to compare the calcium responses during the early stages of MAIDS (week 9 or earlier) between T cells and B cells and between CD4+Thy-1- and CD4+Thy-1+ T cells. B cells were strikingly less affected than T cells: their baseline [Ca2+]i did not significantly increase, and their calcium response to anti-IgM antibody and concanavalin A (Con A) was partially maintained. In contrast, the response to Con A was completely abolished in T cells. Interestingly, calcium mobilization in response to membrane receptor-independent stimuli such as ionophores and thapsigargin was strongly inhibited in T cells, while no such inhibition was found in B cells. In comparison with their CD4+Thy-1+ counterparts, CD4+Thy-1- T cells had blunted calcium responses in controls, as well as in infected mice. However, CD4+Thy-1+ T cells were also strikingly altered, suggesting that the loss of membrane Thy-1 could be associated with, but not directly responsible for abnormalities of calcium responses in CD4+ T cells from RadLV-Rs-infected mice.
Moutschen
M
M
Department of Pathology, University of Liège, Belgium.
Trebak
M
M
Greimers
R
R
Colombi
S
S
Boniver
J
J
D000818:Animals; D016175:B-Lymphocyte Subsets / Q000187:drug effects / Q000276:immunology*; D000001:Calcimycin / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism*; D017493:Leukocyte Common Antigens / Q000032:analysis; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D016183:Murine Acquired Immunodeficiency Syndrome / Q000276:immunology*; D016176:T-Lymphocyte Subsets / Q000187:drug effects / Q000276:immunology*; D019284:Thapsigargin / Q000494:pharmacology; D018800:Thy-1 Antigens / Q000032:analysis
D018800:Thy-1 Antigens; D000001:Calcimycin; D019284:Thapsigargin; D017493:Leukocyte Common Antigens; D002118:Calcium