Immunological correlates of cure after immunotherapy in a patient with American Tegumentary Leishmaniasis

GARCIA BUSTOS, MF; PARODI, CM; BARRIO, A; RAMOS, F; MORA, MC; CONVIT, J; BASOMBRIO, MA

Ascochinga, Córdoba

Encuentro; XXIV Reunión Anual de la Sociedad Argentina de Protozoología; 2010

Sociedad Argentina de Protozoología

A 40 years old patient presented an ulcer on the right leg. Samples of the lesion were taken to provide material for Leishmania studies. Both polymerase-chain reaction (PCR) with generic Leishmania primers and the Montenegro intradermal reaction were positive. The PCR samples were subjected to PS-PCR (Polymorphism Specific - PCR) for identification of Leishmania species. A 78 bp band identifying the Leishmania subgenus and a 62 bp band, characteristic of infection by L. (L.) amazonensis were detected. Since this patient presented cardiovascular risk factors (cardiomegaly, obesity), we explored an alternative treatment to conventional chemotherapy: immunotherapy (IT). The patient received 3 intradermal doses, at 6-7 week intervals of 600 millions heat-inactivated L. (L.) amazonensis promastigotes and 0.075 mg of BCG vaccine. At the time of the second dose, the lesion was completely healed and remained so up to the last control, 16 months post treatment. Flow-cytometry analysis was performed on the CD4 and CD8 T cell populations from peripheral blood in order to evaluate the dynamics of specific surface and intracellular markers at different time points of the patient follow up. We investigated percentages of some T-cell differentiation (CD27, CD28, CD127), memory (CD45RA, CD45RO) and senescence receptors (CD57), and the cytolytic molecule perforin in order to determine if there was a relationship between expression of these markers and disease progression. The patient vs. 12 subjects without history of Leishmaniasis and not undergoing any acute illness were studied (N). Samples from the patient were taken before receiving IT (T1), 3 months (T2), and 12 months (T3) post-treatment. This patient presented an advanced T cell differentiation phenotype at the time of initial diagnosis but later on, after IT, a tendency was observed toward reverting that phenotype, approaching the values of the control group. These differences were more profound comparing CD8 T cells (CD45RA T1, T2, T3= 65.83 ± 0.89 % vs. N= 73.85 ± 3.03 %. Mean ± SEM; CD45RO T1= 31.40 %, T2= 31.38 %, T3= 48.92 % vs. N= 31.35 ± 4.72; CD27/CD28 co-expression T1= 35.02 %, T2= 33.88 %, T3= 58.50 % vs. N= 70.44 ± 5.30 %; CD127 T1= 54.61 %, T2= 42.66 %, T3 68.83 % vs. N= 77.99 ± 5.17 %; CD57 T1= 37.63 %, T2= 25.76 %, T3= 21.17 % vs. N= 14.92 ± 3.78 %; perforin T1= 31.67 %, T2= 22.62 %, T3= 17.45 % vs. N= 19.68 ± 3.67 %). This could indicate a good response to therapy, not only evaluating the patient with clinical, but also with immunologic criteria.