Transforming growth factor beta is protective in host resistance against Listeria monocytogenes infection in mice

The role of transforming growth factor beta (TGF-beta) in host resistance against Listeria monocytogenes infection was studied with mice. The constitutive expression of TGF-beta 1 mRNA was observed in the spleens and livers of mice before and after infection. Injecting the mice with anti-TGF-beta 1 peptide serum resulted in diminished antilisterial resistance, whereas the administration of human platelet-derived TGF-beta 1 enhanced the resistance. Moreover, mice were protected against lethal infection when treated with TGF-beta 1. These results suggest the TGF-beta 1 might be involved in antilisterial resistance. On the other hand, injecting the mice with TGF-beta 1 resulted in a decrease in the titers of endogenous gamma interferon, tumor necrosis factor alpha, and interleukin-6, which are crucial in antilisterial resistance, in sera and in extracts of spleen and liver. Thus, a complicated mechanism might be involved in the role of TGF-beta 1 in host resistance against L. monocytogenes infection.