Role of T cells in the adjuvant effect of Bacillus firmus on the immune system of mice: intranasal and intratracheal immunization study with ovalbumin.
Functions of T cells were determined after intranasal and intratracheal immunization of mice with ovalbumin (Ova) and Bacillus firmus (Bf), a Gram-positive nonpathogenic bacterium of the external environment, or delipidated Bf (dBf) as adjuvants, with the aim to elucidate the mechanism of support of Ova-specific antibody production caused by Bf that had been observed in an identical experiment. Neither Bf nor dBf in a mixture with Ova stimulated Ova-specific T-cell response tested as antigen-specific blast transformation. By contrast, a mild polyclonal stimulation was observed in splenocytes from mice given dBf. In vitro incubation of splenocytes with 100 micrograms (but not 10 micrograms) of Bf or dBf led to a highly significant inhibition of proliferation below the control level in all groups of animals. Supernatants of splenocyte cultures were further tested for cytokine production. IL-10 and IFN-gamma were released after in vitro challenge with dBf and in some cases also with Bf. Analysis of sera demonstrated that administration of Ova + adjuvant brought about an increase in anti-Ova IgG1, IgG2a and IgG2b whereas treatment with Ova alone caused a rise in IgG1 only. The role of Bf or dBf in the enhancement of antigen-specific antibody production could be in influencing macrophages and inducing cytokine milieu composed of IL-10, IFN-gamma and other factors that leads to a bystander stimulation of specifically activated Ova-B cell receptor (Ova-BCR)-bearing cells.
Mlcková
P
P
Institute of Immunology and Microbiology, 1st Faculty of Medicine, Charles University, 128 00 Prague, Czechia.
Cechová
D
D
Marusková
L
L
Chalupná
P
P
Novotná
O
O
Prokesová
L
L
D000276:Adjuvants, Immunologic / Q000008:administration & dosage / Q000494:pharmacology*; D000281:Administration, Intranasal; D000818:Animals; D001407:Bacillus / Q000276:immunology*; D016207:Cytokines / Q000276:immunology / Q000378:metabolism; D005260:Female; D007114:Immunization / Q000379:methods / Q000592:standards; D007074:Immunoglobulin G / Q000097:blood; D008213:Lymphocyte Activation / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D010047:Ovalbumin / Q000008:administration & dosage / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*
D000276:Adjuvants, Immunologic; D016207:Cytokines; D007074:Immunoglobulin G; D010047:Ovalbumin