Cytokine profiles in tuberculosis patients and healthy subjects in response to complex and single antigens ofMycobacterium tuberculosis

Abstract

Peripheral blood mononuclear cells (PBMC) were obtained from tuberculosis (TB) patients and Mycobacterium bovis bacillus Calmette-Guerin vaccinated healthy subjects. PBMC were tested for secretion of tumor necrosis factor-alpha (TNF-alpha), interferon-gamma (IFN-gamma), interleukin-5 (IL-5) and IL-10 in response to complex (whole cells, culture filtrate and cell walls), single secreted (Ag85B, ESAT6, MPT64, PstS and MPT70) and single cytosolic (DnaK, GroES and GroEL) antigens of Mycobacterium tuberculosis. In the absence of antigens, detectable concentrations of TNF-alpha, IFN-gamma and IL-10 were secreted by PBMC of both donor groups, but the concentrations of only IL-10 were significantly higher (P=0.015) in TB patients than in healthy subjects. In the presence of complex antigens, PBMC secreted IFN-gamma and TNF-alpha in response to all three preparations, whereas IL-10 was secreted in response to whole cells and cell walls only. In the presence of single antigens, IFN-gamma was secreted in response to Ag85B, ESAT6 and MPT64 in TB patients and ESAT6 in healthy donors. Except for GroEL and DnaK, single antigens did not induce TNF-alpha and IL-10 secretion from PBMC in either donor group. The secretion of IFN-gamma, but not IL-10, in the presence of Ag85B, ESAT6 and MPT64 supports their potential as subunit vaccine candidates against TB.

Comparative Evaluation of MPT83 (Rv2873) for T Helper-1 Cell Reactivity and Identification of HLA-Promiscuous Peptides in Mycobacterium bovis BCG-Vaccinated Healthy Subjects

“…S1 in the supplemental material). In addition, ProPred identified 11 T-cell epitope regions of 9 to 24 residues in length, which were scattered throughout the MPT83 sequence, i.e., amino acids 4 2/9 0/9 0/9 0/9 0/9 7/9 9/9 1/9 0/9 4/9 3/9 9/9 DRB1.7 2/2 0/2 0/2 0/2 0/2 2/2 0/2 0/2 0/2 0/2 0/2 2/2 DRB1. 8 6/6 5/6 1/6 4/6 0/6 0/6 4/6 1/6 0/6 6/6 1/6 6/6 DRB 9/9 7/9 0/9 0/9 1/9 0/9 4/9 0/9 0/9 8/9 8/9 9/9 DRB1.…”

“…Antigen-and peptideinduced proliferation of PBMCs was performed by using standard procedures (4). In brief, PBMCs (2 ϫ 10 5 cells/well) suspended in 50 l of complete tissue culture medium were seeded into the wells of 96-well tissue culture plates (Nunc, Roskilde, Denmark).…”

Vaccines against Mycobacterium Tuberculosis: Exploring Alternate Strategies to Combat a Near-perfect Pathogen

“…The memory B cell response in BCG-vaccinated individuals have been shown to be present even 45 years following vaccination [19]. Yet this response, which may initiate clearance, is not sufficient to prevent infection of the individual [15,25,26].…”

“…There is evidence to suggest that the stunting of the humoral response may be due to exposure to other environmental mycobacterial [ [28] have shown that while there is an initial antibody response to these antigens, the next steps involving the complement pathway are suppressed. In addition, Espitia et al [15], Al-Attiyah et al [26] and Rennie et al [25] have shown that antibodies to the Ag85 complex and other environmental mycobacteria can be found in the sera of subjects with no prior Mtb exposure. Furthermore, this presentation does not protect the individual from infection [9].…”

Diagnostic and Vaccine Potentials of ESAT-6 Family Proteins encoded by M. tuberculosis genomic regions absent in M. bovis BCG

“…Although, these genes have only 10-35% homology to esat6, they are approximately of the same size (ca 100 aa) and share a similar genomic organization. Because of the immunodominance of ESAT-6 (ESXA) [12][13][14][15][16][17][18], other ESAT-6 family proteins have also received considerable attention for immunological evaluation [19][20][21]. As given below, the genes of some of these proteins are present in M. tuberculosis-specific genomic regions, and therefore they have been considered useful in the diagnostic and vaccine applications [2][3][4][5][6].…”