Cytokine production and lymphocyte proliferation in patients with Nocardia brasiliensis actinomycetoma.

IFN-gamma, TNF-alpha, IL-4, IL-10 and IL-12 concentrations in the supernatant of peripheral blood mononuclear cell (PBMC) cultures and the in vitro proliferation of PBMC were studied in 25 patients with actinomycetoma caused by Nocardia brasiliensis and in 10 healthy controls from endemic zones. Cell cultures were stimulated by a N. brasiliensis crude cytoplasmic antigen (NB) and five semi-purified protein fractions (NB2, NB4, NB6, NB8, and NB10) separated by isoelectric. Phytohemagglutinin (PHA) and purified protein derivative (PPD) of Mycobacterium tuberculosis were used as control antigens. Skin tests were performed by injecting 0.1 ml of candidin and PPD intradermally (ID). Patients showed a poor response to tuberculin, while their response to candidin was more than two fold greater than that observed in the controls. Cell proliferation showed no statistically significant differences in either group. IFN-gamma production was higher in the healthy controls than in the patients, whereas TNF-alpha secretion was slightly higher in the patients' cultures. IL-4 was detected in the patients' cultures but not in the controls. IL-10 and IL-12 were present at low concentrations in both groups. These results suggest that patients with actinomycetoma show normal antigen recognition, but with low IFN-gamma production, and higher concentrations of IL-4, IL-10 and TNF-alpha in the patients' PBMC cultures, indicating that they probably have a Th2 type of immune response.

Diagnosis of cutaneous leishmaniasis.

PURPOSE OF REVIEW: The purpose of this review is to discuss some of the most important issues in the clinical and laboratory diagnosis of cutaneous leishmaniasis. The former is based on clinical experience and the latter on the literature published within the last couple of years. The sensitivity and specificity of old and novel tests to identify the parasite, antigenic products, the host's immune response, and the molecular diagnosis by the PCR are considered here. RECENT FINDINGS: Recent clinical and laboratory research has addressed the individual, entomological, and epidemiological aspects of acute and chronic forms of cutaneous leishmaniasis. Traditional diagnostic investigations for individual cases include the search of suggestive history and clinical features, the identification of amastigotes by histology or direct microscopy, and the growth of promastigotes in culture. Diagnosis by the polymerase chain reaction seems to be approaching a 'gold standard' status as novel techniques offer considerable advantages in the collection and transport of specimens and DNA extraction procedures that are more efficient in individual and field-based protocols. Several authors have reported consistent 100% specificity with increasing sensitivity that overall is between 92 and 98%. Moreover the PCR approach makes possible the fast identification at the Leishmania species and subspecies level. SUMMARY: The diagnostic tools discussed in this review are relevant not only for the diagnosis in endemic regions of the world but also for travellers and workers that following exposure return to non-endemic countries.

Importancia de los antígenos protéicos de Mycobacterium leprae: uso potencial para el desarrollo de una vacuna contra la lepra / Importance of the proteic antigen from Mycobacterium leprae. Potential use for the development of an anti-leprosy vaccine

En la revisión se describen las estructuras antigénicas de M. leprae que se consideran importantes para el desarrollo de una vacuna contra la lepra. Se mencionan los productos biológicos actualmente empleados en la vacunación e inmunoterapia de esta enfermedad y se consideran las posibilidades de contar en el futuro con una vacuna efectiva y de bajo costo obtenida mediante técnicas recombinantes de biología molecular. Se inicia esta revisión con la descripción de la epidemiología y el control de la lepra, que constituyen el marco de referencia relevante de esta infeccción