INFLUENCE OF DIETARY-PROTEIN RESTRICTION ON IMMUNE COMPETENCE .2. EFFECT ON LYMPHOID-TISSUE

  • 1 January 1976
    • journal article
    • research article
    • Vol. 26  (2) , 314-326
Abstract
Weanling mice fed a 4% protein diet showed a generalized loss of lymphoid tissue which was greater than the loss of total body weight. This effect was greatest in the thymus > spleen > mesenteric lymph node. Cell loss was most pronounced during the 1st wk on diets, then remained stable levels for 3 wk and showed a gradual rise thereafter. The effect was mediated partly by a cessation of growth in lymphoid organs due to the low protein intake and an adrenal corticosteroid induced lympholysis which actually reduced cell numbers. Recirculating T [thymus-derived] cells and resident B [bone marrow-derived] cells were among the least affected cells, whereas stem cells, non-migratory T cells and other RES cells were most depressed in numbers. At no stage was the germinal center forming capacity of the mesenteric node lost, although cell recruitment to antigenically stimulated nodes was diminished. During nutritional repletion the spleen, thymus and mesenteric node all showed different and characteristic regrowth. The spleen was most active initially and rapidly reconstituted hemopoietic cells and B cells. This was followed by the thymus which showed a delayed reinitiation of its normal growth kinetics which was interrupted by the diet. Full rehabiliation of the immune apparatus took place even after 2 mo. of nutritional deprivation.