Immune response pattern of the popliteal lymph nodes of dogs with visceral leishmaniasis

Autor(es)

Reina Moreira, Pamela Rodrigues ^[1] ; Vieira, Lais Mendes ^[1] ; Costa de Andrade, Mariana Macedo ^[1] ; Bandarra, Marcio de Barros ^[1] ; Machado, Gisele Fabrino ^[2] ; Munari, Danisio Prado ^[3] ; Vasconcelos, Rosemeri de Oliveira ^[4]

Afiliação do(s) autor(es)

^[1] Univ Estadual Paulista, Dept Patol Anim, FCAV, BR-14884900 Sao Paulo - Brazil

^[2] Univ Estadual Paulista, Dept Clin Cirurgia & Reprod Anim, FOA, BR-14884900 Sao Paulo - Brazil

^[3] Univ Estadual Paulista, Dept Ciencias Exatas, FCAV, BR-14884900 Sao Paulo - Brazil

^[4] Univ Estadual Paulista, Dept Patol Vet, FCAV, BR-14884900 Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Parasitology Research; v. 107, n. 3, p. 605-613, AUG 2010.
• Citações Web of Science: 12

Resumo

The present study aimed to estimate the cell response and parasite load in the popliteal lymph nodes of dogs with visceral leishmaniasis (VL), comparing these findings with the clinical staging of the disease. From the necropsy, 33 dogs were classified as symptomatic (S), asymptomatic (A), or oligosymptomatic (O). Cytology and histopathology were used to determine any presence of microscopic lesions and immunohistochemistry, for parasite load. Dog hyperimmune serum was used as the primary antibody. The inflammatory infiltrate in lymph nodes consisted of macrophages and plasmocytes. The granulomas invaded the trabecular and sinusoid regions and sometimes compressed the lymphocytes of the cortical region (atrophy) and medullary cord cells. Parasite load intensity was unrelated to the density of the macrophages infiltrating the lymph node. Significant differences in parasite load (P < 0.05) were observed between the three groups of infected dogs. Follicular hyperplasia of the cortical region occurred among A and O, while follicular atrophy predominated among S. The parasite load was the greatest among S, followed by O. It can be concluded that, regardless of clinical condition, the most evident cell response consisted of macrophages and plasmocytes. Lymphoid atrophy was observed among animals with intense granulomatous reaction and high parasite load, such as among the symptomatic dogs (P < 0.05). Likewise, the oligosymptomatic dogs also presented high density of parasites in the lymph nodes. Thus, we can confirm that dogs with clinical manifestations of VL have an immune system that is less effective for controlling infection by Leishmania chagasi, thereby favoring parasite multiplication. (AU)

• Processo FAPESP: 09/07815-4 - Avaliação da expressão de MIF,iNOS e MHC-II em macrófagos de linfonodos de cães com leishmaniose visceral
• Beneficiário: Rosemeri de Oliveira Vasconcelos
• Modalidade de apoio: Auxílio à Pesquisa - Regular