LIVER AND INTESTINAL FATTY-ACID-BINDING PROTEINS IN CONTROL AND TGF-BETA-1 GENE TARGETED DEFICIENT MICE

The effect of transforming growth factor beta-1 (TGF beta 1) expressio n on fatty acid binding proteins was examined in control and two strai ns of gene targeted TGF beta 1-deficient mice. Homozygous TGF beta 1-d eficient 129 x CF-1, expressing multifocal inflammatory syndrome, had 25% less liver fatty acid binding protein (L-FABP) when compared to co ntrol mice. The decrease in L-FABP expression was not due to multifoca l inflammatory syndrome since homozygous TGF beta 1-deficient/immunode ficient C3H mice on a SCID background had 36% lower liver L-FABP than controls. This effect was developmentally related and specific to live r, but not the proximal intestine, where L-FABP is also expressed. Fin ally, the proximal intestine also expresses intestinal-FABP (1-FABP) w hich decreased 3-fold in the TGF beta 1-deficient/immunodeficient C3H mice only. Thus, TGF beta 1 appears to regulate the expression of L-FA BP and I-FABP in the liver and the proximal intestine, respectively.