ABSTRACT
Thirty lepromatous (BL-LL) and 25 tuberculoid (TT-BT) nerve lesions obtained from untreated cases of leprosy were scanned using transmission electron microscope for assessing the bacterial load in different cell types. Major bulk of infection was seen in the Schwann cells of nonmyelinated fibres, in both early lepromatous and tuberculoid nerve lesions, suggesting that M. leprae spread mainly via the Schwann cells within the nerve.
Subject(s)
Colony Count, Microbial , Humans , Leprosy, Lepromatous/microbiology , Leprosy, Tuberculoid/microbiology , Microscopy, Electron , Mycobacterium leprae/isolation & purification , Nerve Fibers/microbiologySubject(s)
Health Expenditures , Health Services Administration , India , Poverty , Social Conditions , United NationsABSTRACT
Various mechanisms for nerve damage in tuberculoid leprosy have been proposed. A common feature amongst them is the crucial role played by T-cells. Therefore, the present study was designed to determine the role of T-cells in the induction of nerve damage in leprosy using two different protocols for obtaining graded levels of T-cell depletion: (i) Cyclosporine A, for depletion of T-helper cells and (ii) Anti Thy 1.2, for total depletion of T-cells. The findings indicate that the early changes seen in the unmyelinated fibres may not involve T-cells. However, the later stages of nerve damage associated with demyelination are dependent on T-cell responses.
Subject(s)
Animals , Cyclosporine/pharmacology , Demyelinating Diseases/etiology , Female , Isoantibodies/immunology , Leprosy/microbiology , Mice , Mycobacterium leprae/growth & development , Sciatic Nerve/pathology , T-Lymphocytes/physiologyABSTRACT
Intracellular localization of antileprosy drugs dapsone (DDS) and rifampicin (RFP) was carried out on skin and nerve lesions obtained from multidrug treated, multi (BL-LL)- and pauci (BT-TT) bacillary cases of leprosy using immunocytochemical techniques. Intracellular localization of the above drugs especially in macrophages and Schwann cells was aimed by using rabbit raised anti DDS and RFP polyclonal antibody in an indirect peroxidase assay. Our study records both intra and extracellular staining with anti DDS and RFP antibodies in the skin as well as nerve lesions of MB and PB cases treated with MDT. All the nerves under investigation had moderate to severe pathology and hence free diffusion of the drug could be attributed to the broken barrier. Basal lamina around the Schwann cell did not seem to form a barrier. It was also noted that the drug (metabolite) persisted over a long period of time).