Chemokine mRNA expression after bacterial oral infection in IL-12/23p40-/- mice.

ORTEGA N; CARGNELUTTI E; DI GENARO S

Ciudad de La Punta, San Luis

Congreso; XXVII Reunión Científica Anual de la Sociedad de Biología de Cuyo - 2009; 2009

Sociedad de Biología de Cuyo

Chemokines are small peptides that promote leukocyte migration into tissues. The cytokine interleukin (IL)-12 plays a protective role against the enteropathogenic bacteria Yersinia enterocolitica (Ye). IL-12 is composed by two subunits, p40 and p35. The subunit p40 is also present in IL-23.  The protective role of IL-12/23p40 in the mucosal tissue after Ye oral infection is still unknown. A cross-talk between cytokines and chemokines may explain protective effects of cytokines. In this work we compared chemokine mRNA expression in mesenteric lymph node (MLN) after oral Ye infection in wild-type (WT) and IL-12/23p40-/- C57BL/6 mice. The mice were infected orogastrically with 9 x 107 colony forming units (CFU) of Ye. Twenty-four hours after infection, MLN were removed and total RNA was extracted. RT-PCR was performed using specific primers for the chemokines: macrophage inflammatory protein (MIP)-2 and monocyte chemoattractant protein (MCP)-1. We found significantly lower expression of both MIP-2 and MCP-1 mRNA (p<0,05) in MLN from IL-12/23p40-/- mice compared with those from WT mice. We concluded that up-regulation of chemokine transcripts could be one of the mechanisms involved in the mucosal protective role of IL-12/23 p40 against Ye infection.