The gene for the extracellular alpha antigen of Mycobacterium kansasii was cloned by using the alpha-antigen gene fragments of M. bovis BCG as probes. Gene analysis revealed that this gene encodes 325 amino acid residues, including 40 amino acids for the signal peptide, followed by 285 amino acids for the mature protein. A comparison of the nucleotide sequences of the genes isolated from these ...

Arabinomannan (AM) is a polysaccharide antigen of the mycobacterial capsule. However, it is uncertain whether AM constitutes an immunologically distinct fraction of Mycobacterium tuberculosis. In this study, we analyzed the repertoire and specificity of antibodies to AM by using AM-binding murine monoclonal antibodies (MAbs) and human serum samples. Murine MAbs were found to be diverse in their...

Activation of both CD4(+) and CD8(+) T cells is required for an effective immune response to an M. tuberculosis infection. However, infected macrophages are poor antigen presenting cells and may be spatially separated from recruited T cells, thus limiting antigen presentation within a granuloma. Our previous studies showed that infected macrophages release from cells small membrane-bound vesicl...

Mycobacterium tuberculosis infection elicits antigen-specific CD8(+) T cells that are required to control disease. It is unknown how the major histocompatibility complex class I (MHC-I) pathway samples mycobacterial antigens. CFP10 and ESAT6 are important virulence factors secreted by M. tuberculosis, and they are immunodominant targets of the human and murine T-cell response. Here, we test the...

An ubiquitin conjugated multivalent mycobacterial gene vacIII (containing seven immunogenic mycobacterial epitopes or genes; esat-6 (P1), esat-6 (P2), phos1 (65-83), phos1 (129-137), phos1 (166-175), hsp 16.3 and mtb 8.4) was developed and packaged in different modes of antigen delivery systems including 1) DNA vaccination (pVaxVacIII), 2) oral vaccine strain Salmonella typhi Ty21a as a deliver...

Patients with acquired immunodeficiency syndrome (AIDS) who have Mycobacterium avium-Mycobacterium intracellulare (MAI) infection typically have widely disseminated disease, often fail to respond to multi-drug chemotherapeutic regimens, and show little or no inflammatory tissue response. To determine if this clinicopathologic state correlates with in vitro lymphocyte responses to specific antig...

Gamma interferon (IFN-gamma) is a key cytokine in host defense against intracellular mycobacterial infection. It has been believed that both CD4 and CD8 T cells are the primary sources of IFN-gamma. However, the relative contributions of CD4 and CD8 T-cell subsets to IFN-gamma production and the relationship between CD4 and CD8 T-cell activation have not been examined. By using a model of pulmo...

The immune protection initiated by γδ T cells plays an important role in mycobacterial infection. The γδ T cells activated by Mycobacterium tuberculosis-derived nonpeptidic, phosphorylated biometabolites (phosphoantigens) provide only partial immune protection against mycobacterium, while evidence has suggested that protein antigen-activated γδ T cells elicit effective protective immune respons...

Cattle were inoculated with Mycobacterium bovis, Mycobacterium tuberculosis, or Mycobacterium kansasii to compare the antigen-specific immune responses to various patterns of mycobacterial disease. Disease expression ranged from colonization with associated pathology (M. bovis infection) and colonization without pathology (M. tuberculosis infection) to no colonization or pathology (M. kansasii ...