@article{1672,
  keywords = {Antibodies, Bacterial, Cells, Cultured, Cytokines, Granulocyte-Macrophage Colony-Stimulating Factor, Humans, Immunoglobulin Class Switching, Immunoglobulin G, Interferon-gamma, leprosy, Macrophages, T-Lymphocytes, Tumor Necrosis Factor-alpha},
  author = {Hussain R and Kifayet A and Dojki M and Dockrell H M},
  title = {Selective correlation of interferon-gamma, tumour necrosis factor-alpha and granulocyte-macrophage colony-stimulating factor with immunoglobulin G1 and immunoglobulin G3 subclass antibody in leprosy.},
  abstract = {<p>Dysregulation of both B- and T-cell responses is observed in leprosy. Immunoglobulin G1 (IgG1) and IgG3 antibody subclasses are selectively elevated towards the lepromatous or disseminated form of the disease accompanied by a depression of T-cell responses. T-cell and macrophage cytokines influence antibody class switching, differentiation and proliferation of B cells. To understand the dynamic nature of the immune response in leprosy, we examined the relationship between circulating Mycobacterium leprae-specific antibodies and secreted cytokines [interferon-gamma (IFN-gamma), interleukin-2 (IL-2), IL-5, IL-10, IL-6, tumour necrosis factor-alpha (TNF-alpha) and granulocyte-macrophage colony-stimulating factor (GM-CSF)] in leprosy patients (19 lepromatous patients; 25 tuberculoid patients) and their exposed household contacts (HC=14) in response to M. leprae antigens. Paired comparison revealed a highly significant negative correlation between IFN-gamma and IgG (P=0.016), IgG1 (P<0.001) and IgG3 (P=0. 007) antibodies. No significant relationship was observed with other T-cell cytokines (IL-2, IL-5 and IL-10). These results strongly suggest that IFN-gamma may play a role in down-regulating antigen-specific IgG1 and IgG3 antibodies. Among the macrophage cytokines, TNF-alpha and GM-CSF which have not been shown to play a role in B-cell activation were positively associated with IgG1 (TNF-alpha, P=0.0005; GM-CSF, P=0.001) and IgG3 (TNF-alpha, P=0.001; GM-CSF, P=0.021) antibodies. Since macrophages have high-affinity Fc receptors for IgG1 and IgG3, it is possible that antigen uptake via these receptors may influence cytokine expression of TNF-alpha, a key modulator of disease pathogenesis in mycobacterial diseases. We are currently investigating the role of Fc receptors on activated macrophages, in expression of pro-inflammatory cytokines in mycobacterial diseases.</p>},
  year = {1999},
  journal = {Immunology},
  volume = {98},
  pages = {238-43},
  month = {1999 Oct},
  issn = {0019-2805},
  doi = {10.1046/j.1365-2567.1999.00876.x},
  language = {eng},
}