Diferenças na expressão do receptor para complemento tipo 1 (CR1/CD35) em hemácias e leucócitos de pacientes com leishmaniose visceral, antes e após o tratamento

• Autor(a) principal: Carneiro, Isabel Paiva Dias Mendes
• Data de Publicação: 2015
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da Universidade Federal do Ceará (UFC)
• Texto Completo: http://www.repositorio.ufc.br/handle/riufc/44192
• topic: Leishmaniose Visceral; Eritrócitos; Leucócitos

Visceral leishmaniasis or Kala-azar is a chronic systemic disease, endemic in northeastern Brazil, caused by the parasite Leishmania infantum chagasi and transmitted by the bite of the sand fly Lutzomyia longipalpis. Laboratory findings of pancytopenia are associated with polyclonal activation of B cells, with high levels of circulating immune complexes (CIC). The receptors for complement type 1 (CR1/CD35) in erythrocytes (CR1/E) and in neutrophils (CR1/N) have the function of CIC clearance. The expression of CR1 is modulated during diseases and tends to normalize after a period of remission. Reducing the CR1/E was observed in autoimmune diseases and chronic infectious diseases, being correlated with increased levels of CIC and the severity of symptoms. It has also been observed a reduction in the CR1/N in autoimmune diseases. This study aimed to investigate in patients with Kala-azar, before and after treatment, the expression of CR1 on erythrocytes and leukocytes by flow cytometry and measuring circulating immune complexesby enzyme immunoassay. At the moment of diagnosis, patients compared with the healthy control group showed a reduction in the expression of CR1/E, as well as the frequency of erythrocytesCD35+. There was also a reduction in the expression of CR1/N without reducing the frequency of neutrophilsCD35+, while in lymphocytes and monocytes there was an increase in CR1 expression. After 24 days of treatment, the expression of CR1/E and CR1/N increased significantly, showing a tendency to recover after treatment. CR1expression in monocyte decreased and CR1expression in lymphocyte showed a tendency to normalization. Before treatment, 66% of patients, CIC levels were approximately nine times higher and no correlation with the expression of CR1/E. After treatment, a reduction in CICwas observedbut the levels yet still remaining above the normal. The results suggest that differences in expression of the CR1 in erythrocytes and leucocytesmay be considered a phenomenon acquired with pathology, but no correlation with the levels of circulating immune complexes.