Effect of dietary nucleotides on response to bacterial infections.

A nucleotide-free diet (NFD) suppresses cellular immunity including suppression of both murine allograft rejection and murine graft-vs-host disease in H2 mismatched marrow recipients. To explore the effect of this diet upon response to a bacterial challenge, BALB/c mice were placed upon one of four diets: NFD, NFD supplemented with 0.25% RNA (NFR) and NFD reconstituted with either 0.06% adenine (NFA) or 0.06% uracil (NFU). After 8 weeks on the diets, which supported normal growth in all groups, each dietary group of 10 mice was challenged with an intravenous injection of 1 X 10(7) live Staphylococcus aureus (Strain ATCC 25923). By 120 hr postinoculation all mice in the NFD group had died; mortality was only 56% in the NFR group (p less than 0.05). Addition of uracil resulted in mortality similar to that of the NFR group. Addition of adenine resulted in mortality close to that of the NFD group. Thus, dietary nucleotide restriction increases the mortality from staphylococcal sepsis. Addition of certain dietary nucleotides appears to decrease this susceptibility to bacterial challenge.