Antigenic differences among Leishmania amazonensis isolates and their relationship with distinct clinical forms of the disease

Abstract

Immunoblot analysis was used to investigate antigenic differences among clinical isolates of Leishmania amazonensis and their role in the etiology of the disease. Western blots of promastigote homogenates were analyzed with either monoclonal antibodies (MAbs) specific for the L. mexicana complex (M-4, M-6, M-9, and M-11) or polyclonal sera from L. amazonensis infected patients with the various forms of clinical disease. In the case of the MAbs, no significant variation was observed among the strains of L. amazonensis, isolated from cases of cutaneous leishmaniasis (CL), mucocutaneous leishmaniasis (MCL), diffuse cutaneous leishmaniasis (DCL), visceral leishmaniasis (VL) or post kala-azar dermal leishmaniasis (PKDL), in either the relative mobility (Mr) or the quantitative amount (intensity) of the antigenic determinants. In the case of the sera of the infected patients, the patterns of antigenic reactivity of these strains revealed that, despite showing the presence of shared antigens, differences were observed between some of the antigenic components of the various isolates of L. amazonensis that were recognized by a single serum. Differences were also demonstrated between the antigenic determinants of a single isolate of L. amazonensis that were recognized by the different patients' sera. No apparent association was consistently found, however, between the Mr components identified in these isolates and the clinical form of the disease or the geographical area of isolation. In addition, the spectrum of antigens recognized by the sera from patients with the same clinical form were not identical; although in some instances, similar Mr antigens were shared.(ABSTRACT TRUNCATED AT 250 WORDS)

Leishmania (Leishmania) major-infected rhesus macaques (Macaca mulatta) develop varying levels of resistance against homologous re-infections

“…Immunoblot analyses showed that infected monkeys produced antibodies (both IgG and IgG 1 isotypes) which bound to a number of Leishmania antigen components, consistent with human data (Leon et al 1992). A differential decline in leishmanial antigen-specific IgG, IgM, IgE, and IgG subclasses was shown in visceral leishmaniasis patients after chemotherapy (Anam et al 1999), in particular with IgG1 and IgG3 levels being significantly reduced following treatment (Elassad et al 1994, Ghosh et al 1995.…”

“…After rinsing, strips were developed in a satured solution of 3,3'-diaminobenzidine in Tris buffer (pH 7.4) containing 0.01% H 2 O 2 . The techniques have been described in detail previously (Leon et al 1992). (Figs 1, 2), all L. (L.) majorinfected rhesus monkeys inoculated (Experiment 1) in the orbit of the right eye with 10 7 virulent promastigotes developed nodular skin lesions at the site of inoculation.…”

Antileishmanial activity of lapachol analogues

“…In this report, we evaluated the effect of 1 to 6 against two different species of Leishmania from the New World: L. amazonensis which has been associated with all clinical forms of leishmaniasis (Barral et al 1991, Leon et al 1992, and L. braziliensis that usually presents high invasive capacity resulting in deforming mucocutaneous manifestations, and is endemic in the state of Rio de Janeiro, Brazil.…”

Characterization of Endotrypanum Parasites Using Specific Monoclonal Antibodies

“…The final pellet was used for preparation of samples. Antigens of each of the strains tested were prepared as promastigote homogenates containing protease inhibitors (Leon et al 1992). Prior to analysis, the samples were briefly sonicated using a bath sonicator (RAI Research, Model 250 Ultrasonic cleaner) to homogenize the antigens, and then centrifuged (2,000 x g for 10 min, at 4 o C).…”

“…Briefly, the soluble antigen extracts were resolved by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) using 10% slab gels in non-reducing conditions, and electrophoretically transferred to nitrocellulose paper (Schleicher and Schuell, Keene, New Hampshire, USA). The techniques have been described in detail previously (Leon et al 1992).…”