Regulatory role of exogenous IL-10 in the development of immune response versus Cryptococcus neoformans.
The most important event involved in host defence against Cryptococcus neoformans is the development of an adequate cell-mediated immune response. IL-10, abundantly produced during AIDS progression, could be a negative factor that affects the T cell response through its own immunosuppressive action on antigen-presenting cells. To determine whether this cytokine affects the course of immune response against C. neoformans, we added exogenous IL-10 to cultured Cryptococcus-laden monocytes plus T lymphocytes. The data from this study confirmed the down-regulatory effect of exogenous IL-10 on monocytes and expanded the known inhibitory role to include an increase of the deleterious effect due to capsular material of C. neoformans on (i) lymphoproliferation, (ii) down-regulation of MHC class II molecules, (iii) inhibition of IL-2 mRNA expression and protein secretion by T lymphocytes. These results indicate that the presence of IL-10 in AIDS patients, due to the progression of disease, could represent a pivotal problem contributing to augment the pathogenic effect of C. neoformans.
Monari
C
C
Department of Experimental Medicine and Biochemical Sciences, University of Perugia, Italy.
Retini
C
C
Palazzetti
B
B
Bistoni
F
F
Vecchiarelli
A
A
D000908:Antibodies, Fungal / Q000276:immunology; D000917:Antibody Formation; D002478:Cells, Cultured; D003455:Cryptococcus neoformans / Q000502:physiology*; D017931:DNA Primers / Q000737:chemistry; D015536:Down-Regulation; D005434:Flow Cytometry; D000949:Histocompatibility Antigens Class II / Q000378:metabolism; D006801:Humans; D007111:Immunity, Cellular / Q000276:immunology; D016753:Interleukin-10 / Q000502:physiology*; D007376:Interleukin-2 / Q000235:genetics / Q000378:metabolism; D008213:Lymphocyte Activation / Q000276:immunology; D009000:Monocytes / Q000276:immunology* / Q000382:microbiology; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000378:metabolism; D013601:T-Lymphocytes / Q000276:immunology* / Q000382:microbiology
D000908:Antibodies, Fungal; D017931:DNA Primers; D000949:Histocompatibility Antigens Class II; D007376:Interleukin-2; D012333:RNA, Messenger; D016753:Interleukin-10