Your browser doesn't support javascript.
loading
Early high avidity specific IgG production in experimental hamster visceral leishmaniasis.
de Carvalho, Camila Aparecida; Ferrão, Thiago Fidelis; Cavalcante, Fernanda Siqueira; de Freitas, Flavia Regina Novais; Meireles, Luciana Regina; de Andrade Júnior, Heitor Franco.
Afiliação
  • de Carvalho CA; Instituto de Medicina Tropical-Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil. camilacarvalho@usp.br.
  • Ferrão TF; Protozoology Laboratory, Instituto de Medicina Tropical de São Paulo, Avenida Doutor Enéas de Carvalho Aguiar 470, São Paulo, SP, 05403-000, Brazil. camilacarvalho@usp.br.
  • Cavalcante FS; Instituto de Medicina Tropical-Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil.
  • de Freitas FRN; Instituto de Medicina Tropical-Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil.
  • Meireles LR; Instituto de Medicina Tropical-Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil.
  • de Andrade Júnior HF; Instituto de Medicina Tropical-Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil.
Parasitol Res ; 119(11): 3881-3885, 2020 Nov.
Article em En | MEDLINE | ID: mdl-32797264
Visceral leishmaniasis (VL) by Leishmania (Leishmania) infantum is epidemic in Brazil. Hypergammaglobulinemia appears early in patients with VL and is ineffective. Usually, high-affinity IgG B cells are selected during most infections, a critical step for an effective humoral response. The avidity of IgG antibodies in VL is unexplored due to the absence of temporal parameters in most patients, associated to low clinical significance. Experimental infection models overcome this fact, allowing the monitoring of the disease temporal evolution. In this study, the avidity of IgG antibodies was evaluated in experimental models, in infection in hamsters, and in immunization in rabbits. Specific IgG antibodies were detected by ELISA, using chaotropic solution to determine avidity, as reported for viral infections. The levels of IgG antibodies correlated with the progression of experimental infection in hamsters or antigenic stimulation in immunized rabbits. However, IgG avidity was high early in infected animals, even in early periods (> 80%), while in immunized rabbits, they had early antibodies of low avidity with progressive maturation, similar as other infections. These data suggest that the affinity maturation of the avidity of anti-Leishmania IgG antibodies promoted at an early stage, influencing the appropriate interaction between antigens and affecting the disease progression. This fact could be associated to monovalent immune complexes, as reported in human and experimental VL. This scenario may be related to an independent process of immune cell activation by the parasite but absent in antigen preparation used as immunogens.
Assuntos
Palavras-chave
Texto completo
Adicionar na Minha BVS
Imprimir
XML
PubMed Links
Buscar no Google

Texto completo: 1 Coleções: 01-internacional Base de dados: MEDLINE Assunto principal: Imunoglobulina G / Anticorpos Antiprotozoários / Leishmania infantum / Leishmaniose Visceral Limite: Animals / Female / Humans / Male País/Região como assunto: America do sul / Brasil Idioma: En Revista: Parasitol Res Assunto da revista: PARASITOLOGIA Ano de publicação: 2020 Tipo de documento: Article País de afiliação: Brasil País de publicação: Alemanha
Texto completo
Adicionar na Minha BVS
Imprimir
XML
PubMed Links
Buscar no Google

Texto completo: 1 Coleções: 01-internacional Base de dados: MEDLINE Assunto principal: Imunoglobulina G / Anticorpos Antiprotozoários / Leishmania infantum / Leishmaniose Visceral Limite: Animals / Female / Humans / Male País/Região como assunto: America do sul / Brasil Idioma: En Revista: Parasitol Res Assunto da revista: PARASITOLOGIA Ano de publicação: 2020 Tipo de documento: Article País de afiliação: Brasil País de publicação: Alemanha