Enhancement of innate and cell-mediated immunity by antimycobacterial antibodies.
Infect Immun
; 73(10): 6711-20, 2005 Oct.
Article
in En
| MEDLINE
| ID: mdl-16177348
ABSTRACT
We investigated the ability of human antibodies induced by Mycobacterium bovis bacillus Calmette-Guérin (BCG) vaccination to protect against mycobacterial infections. Serum samples containing mycobacterium-specific antibodies were obtained from volunteers who had received two intradermal BCG vaccinations 6 months apart. Significant increases in lipoarabinomannan (LAM)-specific immunoglobulin G (IgG) were detected after both the primary and booster vaccinations. Effects of mycobacterium-specific antibodies on surface binding and internalization of BCG by neutrophils and monocytes/macrophages were studied, using green fluorescent protein (gfp)-expressing BCG. Surface-bound gfp-expressing BCG were distinguished from intracellular BCG by surface labeling with LAM-specific monoclonal antibody. Internalization of BCG by phagocytic cells was shown to be significantly enhanced in postvaccination serum samples. Furthermore, the inhibitory effects of neutrophils and monocytes/macrophages on mycobacterial growth were significantly enhanced by BCG-induced antibodies. The growth-inhibiting effects of postvaccination sera were reversed by preabsorption of IgG with Protein G. Finally, the helper effects of antimycobacterial antibodies for the induction of cell-mediated immune responses were investigated. BCG-induced antibodies significantly enhanced proliferation and gamma interferon production in mycobacterium-specific CD4(+) and CD8(+) T cells, as well as the proportion of proliferating and degranulating CD8(+) T cells. We conclude that mycobacterium-specific antibodies are capable of enhancing both innate and cell-mediated immune responses to mycobacteria.
Full text:
1
Collection:
01-internacional
Health context:
2_ODS3
/
3_ND
Database:
MEDLINE
Main subject:
Tuberculosis
/
CD4-Positive T-Lymphocytes
/
Immunization, Passive
/
CD8-Positive T-Lymphocytes
/
Immunity, Innate
/
Antibodies, Bacterial
/
Mycobacterium bovis
Limits:
Humans
Language:
En
Journal:
Infect Immun
Year:
2005
Document type:
Article