Effect of Lutzomyia longipalpis salivary gland extracts on leukocyte migration induced by Leishmania major.
The mechanism by which the salivary gland lysate (SGL) of Lutzomyia longipalpis enables Leishmania infection remains under investigation. One possibility is that saliva promotes cellular recruitment leading to development of skin lesions. In this study, we investigated leukocyte recruitment induced by L. major, L. major + SGL, or SGL alone into the peritoneal cavity of BALB/c mice. The administration of L. major with or without SGL induced neutrophil migration six hours after infection. Interestingly, after seven days, the BALB/c mice still had eosinophils and mononuclear cells in their peritoneal cavities. Flow cytometric analysis showed an increase in the CD4(+) CD45RB(low) T cell subset (effector or memory cells) compared with the CD4(+) CD45RB(high) subset (naive cells). Moreover, the co-injection of L. major with SGL enhanced production of interleukin-10. These results suggest that SGL can facilitate Leishmania infection by modulating leukocyte recruitment and Th2 cytokine production at the inflammatory focus.
Monteiro
Marta Chagas
MC
Department of Biochemistry and Immunology, and Department of Pharmacology, Ribeirao Preto School of Medicine, University of São Paulo, São Paulo, Brazil. martachagas2@yahoo.com.br
Lima
Hermênio C
HC
Souza
Adelson A Almeida
AA
Titus
Richard G
RG
Romão
Pedro Roosevelt Torres
PR
Cunha
Fernando de Queiroz
FQ
D000818:Animals; D002457:Cell Extracts / Q000494:pharmacology*; D002465:Cell Movement / Q000187:drug effects*; D005260:Female; D007371:Interferon-gamma / Q000378:metabolism; D016753:Interleukin-10 / Q000378:metabolism; D018320:Leishmania major / Q000276:immunology*; D007962:Leukocytes / Q000166:cytology / Q000187:drug effects* / Q000276:immunology / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D011576:Psychodidae; D012469:Salivary Glands
D002457:Cell Extracts; D016753:Interleukin-10; D007371:Interferon-gamma