3 research outputs found
Stability of biochemical analytes of end stage renal failure patients on renal replacement therapy for urea-kinetic modeling in the home dialysis setting
© The Author 2013. Published by Oxford University Press on behalf of ERA-EDTA. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited. For commercial re-use, please contact [email protected] reviewe
Leishmania Promastigote Membrane Antigen-Based Enzyme-Linked Immunosorbent Assay and Immunoblotting for Differential Diagnosis of Indian Post-Kala-Azar Dermal Leishmaniasis
Diagnosis of post-kala-azar dermal leishmaniasis (PKDL), caused by Leishmania donovani, is difficult, as the dermal lesions are of several types and resemble those caused by other skin diseases, especially leprosy. Since the disease generally appears very late after the clinical cure of kala-azar in India, it is also difficult to correlate PKDL with a previous exposure to L. donovani. Very few attempts have been made so far to diagnose PKDL serologically, and the diagnostic methods vary in their sensitivities and specificities. Diagnosis of PKDL through sophisticated PCR methods, although highly sensitive, has limited practical use. We have developed a serodiagnostic method using an enzyme-linked immunosorbent assay to detect specific immunoglobulin (Ig) isotypes and IgG subclass antibodies in the sera of Indian PKDL patients. Our assay, which uses L. donovani promastigote membrane antigens, was 100% sensitive for the detection of IgG and 96.7% specific for the detection of IgG and IgG1. Optical density values for individual patients, however, demonstrated wide variations. Western blot analysis based on IgG reactivity could differentiate patients with PKDL from control subjects, which included patients with leprosy, patients from areas where kala-azar is endemic, and healthy subjects, by the detection of polypeptides of 67, 72, and 120 kDa. The recognition patterns of the majority of serum samples from patients with PKDL were also distinct from those of the serum samples from patients with visceral leishmaniasis (VL), at least for a 31-kDa polypeptide. To further differentiate patients with PKDL from those with active and cured VL, we analyzed the specific titers of the Ig isotypes and IgG subclasses. High levels of IgG, IgG1, IgG2, and IgG3 antibodies significantly differentiated patients with PKDL from patients cured of VL. The absence of antileishmanial IgE and IgG4 in patients with PKDL differentiated these patients from those with active VL. These results imply intrinsic differences in the antibodies generated in the sera from patients with PKDL and VL
IL-10- and TGF-�-Mediated Susceptibility in Kala-azar and Post-kala-azar Dermal Leishmaniasis: The Significance of Amphotericin B in the Control of Leishmania donovani Infection in India1
Visceral leishmaniasis (VL) or kala-azar is known to be associated with a mixed Th1-Th2 response, and effective host defense
requires the induction of IFN-� and IL-12. We address the role of the differential decline of IL-10 and TGF-� in response to
sodium antimony gluconate (SAG) and amphotericin B (AmB), the therapeutic success of SAG and AmB in Indian VL, and the
significance of IL-10 and TGF-� in the development and progression of post-kazla-azar dermal leishmaniasis (PKDL). In the
active disease, PBMC from VL patients showed suppressed Ag-specific lymphoproliferation, IFN-� and IL-12 production, and
elevation of IL-10 and TGF-�. Cure corresponded with an elevation in IFN-� and IL-12 production and down-regulation of IL-10
and TGF-�. Both CD4� and CD8� T cells were involved in IFN-� and IL-10 production. Interestingly, the retention and maintenance
of residual IL-10 and TGF-� in some SAG-treated individuals and the elevation of IL-10 and TGF-� in PKDL, a sequel
to kala-azar, probably reflects the role of these cytokines in reactivation of the disease in the form of PKDL. Contrastingly, AmB
treatment of VL resulted in negligible TGF-� levels and absolute elimination of IL-10, reflecting the better therapeutic activity of
AmB and its probable role in the recent decline in PKDL occurrences in India. Moreover, elucidation of immune responses in
Indian PKDL patients revealed a spectral pattern of disease progression where disease severity could be correlated inversely with
lymphoproliferation and directly with TGF-�, IL-10, and Ab production. In addition, the enhancement of CD4�CD25� T cells in
active VL, their decline at cure, and reactivation in PKDL suggest their probable immunosuppressive role in these disease
forms. The Journal of Immunology, 2007, 179: 5592–5603