Regional cerebral cortical deficits in the immune-deficient nude mouse: a preliminary study

This report examines the morphology of the cerebral cortex in the nude mouse (nu/nu) compared with the BALB/c(+/+). Our experiments indicated that the thickness of the lateral frontal lobe was significantly reduced (8%; P less than 0.005) in the 4-month-old, female nude mouse compared with a BALB/c mouse of like sex and age. In addition, the left hemisphere was, in general, thinner in the nude than in the BALB/c, with area 18 being significantly thinner (2%; P less than 0.005). Oligodendrocytes were less in area 18 in the nude by 25% (P less than 0.02) in contrast to the BALB/c. In some respects these results extend the work of others. In previously published experiments, we showed that the thickness of the frontal cortex from enriched and impoverished female rats (from 60 to 116 days of age) differed by 2 to 3% (P less than 0.001) and in male rats by 3 to 4% (P less than 0.001). The oligodendrocytes in area 18 in the male differed by 20% (P less than 0.02) in rats exposed to their respective enriched or impoverished environments from 25 to 105 days of age. Thus, we have shown that the frontal cortical morphology as well as the occipital cortical oligodendrocytes were altered in both immune-deficient animals and environmentally stimulated or impoverished animals. Based on these separate sets of data, we will be interested to learn if our environmental conditions can alter the immune system and if so by what mechanism.