Diabetes mellitus associated with pentamidine isethionate in diffuse cutaneous leishmaniasis.

The authors report a case of a male patient from Bacabal, MA with diffuse cutaneous leishmaniasis (DCL), for at least nine years, with 168 lesions on his body. These were tumour-like nodules with some ulceration. He used pentavalent antimonial (glucantime) and an association of gamma interferon plus glucantime with improvement of the lesions but relapsed later.

[An evolutionary study of mucosal leishmaniasis (a 7- to 17-year follow-up) due to Leishmania (Viannia) braziliensis in Tres Braços, Bahia].

Seventy seven (68%) patients with mucosal leishmaniasis recorded during the period 1976-1986 in the region of Três Braços, Bahia were traced and re-evaluated clinically, diagnostically and therapeutically. Sixty-five patients were alive. The families of 12 dead patients were interviewed about probable cause of death.

Transforming growth factor-beta in human cutaneous leishmaniasis.

Transforming growth factor (TGF)-beta has several downregulatory functions on the immune system: inhibition of interleukin-2 receptor induction, decrease of interferon-gamma-induced class II antigen expression, inhibition of macrophage activation, as well as cytotoxic and lymphokine-activated killer cell generation. TGF-beta has also been recognized as an important immunoregulator in murine leishmaniasis, for which it increases susceptibility to disease. In the present study we evaluate the involvement of TGF-beta in human leishmaniasis in vitro and in patients with cutaneous leishmaniasis.

Lymphadenopathy as the first sign of human cutaneous infection by Leishmania braziliensis.

This paper describes the presence of transitory lymphadenopathy as an initial sign of cutaneous leishmaniasis, and sometimes the only manifestation of Leishmania braziliensis infection. Ten patients with lymphadenopathy living in an area of L. braziliensis transmission had Leishmania cultivated from their lymph nodes previous to any other manifestation of cutaneous leishmaniasis.

Production of active anti-CD6 mouse/human chimeric antibodies in the milk of transgenic mice.

The expression of chimeric genes in the mammary gland of transgenic farm animals has become an alternative for the large-scale production of recombinant proteins and for the modification of milk composition. In this paper, we show that a mouse/human chimeric antibody against the human CD6 leukocyte antigen can be assembled and correctly folded by the mammary gland, and secreted to milk, where it maintains its specificity. The base sequences encoding for the heavy and light chain variable regions of the anti-CD6 mouse monoclonal antibody IOR-T1 were cloned by the polymerase chain reaction from hybridoma cDNA, coupled to human heavy and light chain constant region genes, and inserted in a vector containing the 5' regulatory region of the rabbit whey acidic protein gene.

Polar and subpolar diffuse cutaneous leishmaniasis in Brazil: clinical and immunopathologic aspects.

Background: Diffuse cutaneous leishmaniasis (DCL) is a rare manifestation of human leishmaniasis, characterized by multiple, slowly progressive nodules or plaques without ulceration, involving almost the entire body. It has been suggested, that DCL results from a lack of cell-mediated immunity to leishmanial antigen, leading to uncontrolled parasite growth.

Methods: We have performed detailed clinical, histopathologic, and immunologic investigations in six patients with DCL.

Antigenicity of cystatin-binding proteins from parasitic protozoan. Detection by a proteinase inhibitor based capture immunoassay (PINC-ELISA).

A novel immunoassay (PINC-ELISA) was designed using proteinase inhibitors of the cystatin superfamily (PINC) in the solid phase, to promote the selective capture of cysteine proteinases. The method was applied in the identification of papain-like antigens from parasitic protozoa. PINC of human origin, namely recombinant cystatin C (r-cystatin C) or low molecular weight kininogen were used in the assays to adsorb proteases contained in cell lysates from various trypanosomatids.

Up-regulation of T helper 2 and down-regulation of T helper 1 cytokines during murine retrovirus-induced immunodeficiency syndrome enhances susceptibility of a resistant mouse strain to Leishmania amazonensis.

Resistance to and recovery from leishmania infection is dependent on cell-mediated immunity. C57BL/6 mice are resistant to Leishmania amazonensis (La) infection but susceptible to LP-BM5 murine leukemia virus (MuLV) infection. MuLV infection leads to a state of immunodeficiency characterized by severe compromise of cell-mediated immunity.

Cytotoxicity in human mucosal and cutaneous leishmaniasis.

CD8+ T cells and lysis of parasitized macrophages seem to be important in the resistance to murine leishmaniasis. In the present study, we evaluated peripheral blood mononuclear cell (PBMC) from patients with either cutaneous (CL) or mucosal (ML) leishmaniasis in cell lysis assays using 51-Cr-labeled Daudi or K562 cells, or autologous antigen-pulsed macrophages as targets. Results are reported as lytic units (number of cells required for 30% lysis) per million PBMC.

Spontaneous regional healing of extensive skin lesions in diffuse cutaneous Leishmaniasis (DCL).

The authors report a case of diffuse cutaneous leishmaniasis, with longstanding evolution and presenting with diffuse infiltrated lesions rich in amastigotes in the absence of mucosal involvement. In situ characterization with monoclonal antibodies revealed Leishmania amazonensis. Large regional lesions have presented spontaneous healing without specific therapy.

Clinical and immunopathological aspects of disseminated cutaneous leishmaniasis.

The clinico-pathological and immunological findings in eight patients from Bahia, Brazil with disseminated cutaneous leishmaniasis are described. This condition differs from anergic diffuse cutaneous leishmaniasis (DCL) and from classical American cutaneous leishmaniasis (ACL). The number of lesions in these patients ranged from 75 to 800 and were characterized by papules and an acneiform type of lesion with a few ulcers rather than nodules that are the main characteristic of DCL.

Transforming growth factor-beta in tegumentary leishmaniasis.

1. The course of infection with the protozoan parasite Leishmania is determined in part by its early replication in macrophages, the exclusive host cells for these organisms. Resistance to and recovery from leishmanial infection is related to cell-mediated immune responses in all forms of human and murine leishmaniasis.

Leishmaniasis recidiva cutis in American cutaneous leishmaniasis.

Background: Leishmaniasis recidiva cutis (LRC) consists of active lesions around or inside the scar of classical cutaneous leishmaniasis (CL). In the literature it is considered as an hyperergic form of CL because the patients show a strong response to intradermal testing with leishmania antigen and, histologically, the parasites are scarce or absent; a well-organized granuloma is always observed.

Methods: Three patients from Bahia (Brazil) with LRC were evaluated by clinical examination, biopsies, skin tests with leishmania antigen, serology, and culture.

Antigen-reactive gamma delta T cells in human leishmaniasis.

The importance of Ag-specific gamma delta T lymphocytes in human immune responses to pathogenic organisms is unknown. In the present study the expression of gamma delta TCR on T lymphocytes from patients with cutaneous, mucosal, or visceral leishmaniasis was examined. All of these patient groups had elevated levels of gamma delta T cells in peripheral blood.

Transforming growth factor beta as a virulence mechanism for Leishmania braziliensis.

Transforming growth factor beta (TGF-beta) has potent down-regulating effects on macrophages and is thus capable of influencing the fate of intramacrophage parasites, including leishmanias. We report the development of a mouse model for the study of the human pathogen Leishmania braziliensis and demonstrate, both in vitro and in vivo, a key regulatory role for TGF-beta in the pathogenesis of infection with this parasite. Recombinant TGF-beta added to cultures of murine peritoneal macrophages led to increased intracellular L.

Lymphadenopathy associated with Leishmania braziliensis cutaneous infection.

Lymph node involvement by Leishmania during human cutaneous leishmaniasis was reported more than 90 years ago, but the importance of certain Leishmania strains in such dissemination remains largely speculative. We have examined 36 consecutively untreated cutaneous leishmaniasis patients early in their disease; 66.7% had enlarged lymph nodes.

Diffuse cutaneous leishmaniasis with atypical aspects.

A 16-year-old man had long-standing diffuse cutaneous leishmaniasis with the following characteristics: diffuse infiltrated lesions rich in amastigotes, absence of mucosal involvement, and lack of parasite-specific cell-mediated immune response. In situ identification of Leishmania mexicana amazonensis was achieved by the use of monoclonal antibodies. Clinically, as an atypical finding there was deep and extensive ulceration in the lower limbs.

Transforming growth factor-beta in leishmanial infection: a parasite escape mechanism.

The course of infection with the protozoan parasite Leishmania is determined in part by their early replication in macrophages, the exclusive host cells for these organisms. Although factors contributing to the survival of Leishmania are not well understood, cytokines influence the course of infection. Transforming growth factor-beta (TGF-beta) is a multipotential cytokine with diverse effects on cells of the immune system, including down-regulation of certain macrophage functions.

Human lymphocyte stimulation by legume lectins from the Diocleae tribe.

Lectins from eight leguminous seeds from the Diocleae tribe were compared to Concanavalin A (Con A), a well known T cell mitogen, on the stimulation of lymphocyte proliferation and Interferon gamma (IFN-gamma) production by peripheral blood mononuclear cells (PBMC) from normal volunteers. Lectins from Canavalia brasiliensis and Dioclea virgata induced the highest lymphocyte proliferation, both much higher than levels obtained with Con A, whereas lectins from Dioclea guianensis var. lasiophylla and from Canavalia bonariensis induced the lowest stimulation.

Diminished in vitro production of interleukin-1 and tumor necrosis factor-alpha during acute visceral leishmaniasis and recovery after therapy.

Disturbance of T cell-mediated immunity has been reported in acute visceral leishmaniasis (AVL). In a study of 16 patients with AVL, defective production of interleukin-1 (IL-1) by peripheral blood mononuclear cells was demonstrated in response to leishmania antigens, heat-killed Listeria organisms, and lipopolysaccharide when compared to posttherapy values or controls. This global defect in IL-1 production was corrected after successful therapy.

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

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.

Immunologic markers of clinical evolution in children recently infected with Leishmania donovani chagasi.

The study attempted to identify immunologic markers for progression of Leishmania donovani chagasi infection to disease in children in an area endemic for visceral leishmaniasis (VL). [3H]thymidine uptake of lymphocytes stimulated with L. donovani chagasi antigen from children with asymptomatic infection (25,286 +/- 11,648) and from children with self-healing subclinical infection (15,511 +/- 4681) was greater (P = .

Leishmania amazonensis infection: a comparison of in vivo leishmanicidal mechanisms between immunized and naive infected BALB/c mice.

In vitro studies have shown that both macrophage activation and destruction of parasitized macrophages lead to leishmania destruction. The relative role played by such mechanisms in vivo have not been properly evaluated. We took advantage of the model of intravenous immunization with solubilized leishmanial antigen which renders partially resistant the otherwise highly susceptible BALB/c mice to address this issue avoiding the interference of different genetic backgrounds.

Serum levels of bothropic venom in patients without antivenom intervention.

Serum kinetics of bothropic venom were evaluated in eight snakebite patients, who due to a national shortage, received no specific antivenom therapy. The cases were clinically classified as mild, moderate, and severe. Patients were bled sequentially and serum levels of venom were assayed by ELISA.