CHEMOKINE AND CHEMOKINE RECEPTORS IN DISTINCT CLINICAL FORMS OF HUMAN TEGUMENTARY LEISHMANIASIS

MARIA JULIA PIMENTEL SOLÁ; GARCÍA BUSTOS, MARÍA F.; MARCO-JORGE, DIEGO; BARROSO, PAOLA; RAGONE, PAULA; MESIAS, ANDREA; PEREZ BRANDAN CECILIA; PARODI, CECILIA

Congreso; EUROPEAN CONGRESS OF IMMUNOLOGY; 2021

The aim of this work was to study the participation of CCL20 and CCL17,chemokines directed to skin and mucosal tissues in cutaneous (CL) and mucosal(ML) leishmaniasis.We processed peripheral blood samples from patients with CL (n=20), ML(n=15) and healthy subjects (HS, n=10). Plasma levels were measured by ELISA. Weevaluated the chemokine receptors CCR4 and CCR6 on CD45RO+ CD4+ and CD8+ Tcells by flow cytometry. Also, PBMC cultures were performed (1x106cells/ml,7 days) in presence of L.braziliensis or L. amazonensis solubleantigens (20ug/ml). Single nucleotide polymorphisms (SNP) for CCL17 and CCL20were analyzed by RLP-PCR and gene fragment digestion. Higher plasma levels of CCL20 (p=0.0017) and diminished values of CCL17(p=0.0023) were found in ML (p=0.0017), indicating that this clinical formpresents altered chemokine patterns. In invitro assays, proteins of L.amazonensis inhibited the supernatant (SN) production of CCL17 (p=0.0085) inML, while L. braziliensis slightly increased the SN production of CCL20 inCL (p=0.038) and ML (p=0.031).We suggest that Leishmania spp. could influence the degree of chemokine responses.The number of CCR4+CCR6+ T cells was similar between groups with the majorityof them expressing CD45RO+. Analyzing SNP, the most frequent genotype for CCL17was CT (CL, 72%; ML, 44%; HS, 80%), while TT genotype predominated for CCL20 (CL,45%;ML,87%; HS,60%). This represents a preliminary approach for chemokinepolymorphisms in leishmaniasis. We need further research to determine theircorrelation with plasma levels and pathology outcome.