Received: October 9, 2007.

Accepted: October 30, 2007.

Abstract published online: October 31, 2007.

Full paper published online: August 31, 2008.

TNF-a AND IL-6 IMMUNOHISTOCHEMISTRY IN RAT RENAL TISSUE EXPERIMENTALY INFECTED WITH Leptospira interrogans

SEROVAR CANICOLA

MARINHO M (1), MONTEIRO CMR (1), PEIRÓ JR (2), MACHADO GF (2), OLIVEIRA-JÚNIOR IS (3)

(1) Department of Animal Health and Production, Dentistry School, FOA, São Paulo State University, UNESP, Araçatuba, São Paulo State, Brazil; (2) Department of Clinics, Surgery and Animal Reproduction, Dentistry School, FOA, São Paulo State University, UNESP, Araçatuba, São Paulo State, Brazil; (3) Inflammatory Mediators Laboratory, Division of Geriatrics and Gerontology, Department of Medicine, Federal University of São Paulo, São Paulo, São Paulo State, Brazil.

ABSTRACT: Leptospirosis is a public health problem worldwide and its etiology remains unclear. Its pathogenesis involves a complex interaction between host and infecting microorganism. The inflammatory reaction that controls the infection process also underscores many pathophysiological events occurring in leptospirosis. We investigated the presence of tumor necrosis factor- (TNF-) and interleukin-6 (IL-6) in renal tissues by immunohistochemical and histopathological examination in animals experimentally inoculated with Leptospira serovar Canicola. All the tests were carried out 2, 7, 14, 21 or 28 days  after inoculation. Although TNF- and IL-6 had been detected in tissues throughout the observation period, these cytokines appeared more intensely during the initial phase of infection. Therefore, both TNF- and IL-6 were associated with the immunopathogenesis of leptospirosis. This profile suggests a high immunocellular response throughout the early infection stages followed by subsequent humoral response.

KEY WORDS: leptospirosis, immunohistochemistry, IL-6, TNF-, mice.

CONFLICTS OF INTEREST: There is no conflict.

FINANCIAL SOURCE: The State of São Paulo Research Foundation (FAPESP), financial aid process n. 2002/10139-1.

CORRESPONDENCE TO:

MÁRCIA MARINHO, Universidade Estadual Paulista, Rua Clóvis Pestana, 793, CEP 16050-680, Araçatuba, São Paulo, Brasil. Phone: +55 18 3636 1382. Fax 55 18 2633-6487. Email: mmarinho@fmva.unesp.br.