Downmodulation of CD18 and CD86 on macrophages and VLA-4 on lymphocytes in experimental tuberculosis.
Development and evaluation of new vaccines and immunotherapy against tuberculosis demand a better understanding of the immune mechanisms in this disease. Costimulatory signals and intercellular contact seem to be pivotal in determining whether recognition of antigen by T cells leads to activation or anergy. In this paper, we show that virulent M. tuberculosis H37Rv downmodulates the ex vivo expression of CD18 and CD86 on peritoneal macrophages and VLA-4 on lymphocytes but does not disturb the in vitro production of interleukin (IL)-12 and interferon (IFN)-gamma after intraperitoneal infection. In addition, splenocytes from infected mice produce IL-10, while the expression of cell surface receptors is unchanged. The interplay among IL-12, IFN-gamma and IL-10 in vivo and the downmodulation of cell-surface receptors during the infection at the inflammatory site may contribute to the explanation of the maintenance of infection.
Bonato
V L
VL
Centre for Tuberculosis Research, Department of Biochemistry and Immunology, School of Medicine of Ribeirão Preto, University of São Paulo, Brazil.
Medeiros
A I
AI
Lima
V M
VM
Dias
A R
AR
Faccioliti
L H
LH
Silva
C L
CL
D000818:Animals; D015703:Antigens, CD / Q000378:metabolism*; D051940:B7-2 Antigen; D018821:CD18 Antigens / Q000378:metabolism*; D015536:Down-Regulation; D066298:In Vitro Techniques; D039041:Integrin alpha4beta1; D016023:Integrins / Q000378:metabolism*; D007371:Interferon-gamma / Q000096:biosynthesis; D016753:Interleukin-10 / Q000096:biosynthesis; D018664:Interleukin-12 / Q000096:biosynthesis; D008213:Lymphocyte Activation; D008214:Lymphocytes / Q000276:immunology*; D017737:Macrophages, Peritoneal / Q000276:immunology*; D008562:Membrane Glycoproteins / Q000378:metabolism*; D051379:Mice; D008807:Mice, Inbred BALB C; D009169:Mycobacterium tuberculosis / Q000472:pathogenicity; D014395:Peritonitis, Tuberculous / Q000276:immunology*; D016201:Receptors, Lymphocyte Homing / Q000378:metabolism*
D015703:Antigens, CD; D051940:B7-2 Antigen; D018821:CD18 Antigens; C497965:Cd86 protein, mouse; D039041:Integrin alpha4beta1; D016023:Integrins; D008562:Membrane Glycoproteins; D016201:Receptors, Lymphocyte Homing; D016753:Interleukin-10; D018664:Interleukin-12; D007371:Interferon-gamma