664 DIMINISHED POLYMORPHONUCLEAR LEUKOCYTE ADHERENCE AND CHEMOTAXIS FOLLOWING PROTEIN CALORIE MALNUTRITION IN NEWBORN RATS: EFFECT OF NUTRITIONAL RESTORATION

Abstract

Recent advances in neonatal intensive care have permitted the survival of very low birthweight infants who in the past might not have lived. Many of these babies, however, are difficult to nourish, and ultimately develop clinical and biochemical signs of malnutrition. These infants may be at greater risk for nosocomial infection than normally nourished hosts. We have compared neutrophil (PMN) adherence (ADH), and chemotactic response (CR) to formyl peptides in a rat model of protein calorie malnutrition (PCM). Wistar rats at 14 days gestation received either a normal (24% protein) or isocaloric (2.5% protein) diet. On day 3, rat pups were divided into 3 groups: 1) pups allowed to nurse on their own dam (normal); 2) normally nourished pups foster nursed onto a malnourished mother (depleted); or 3) malnourished pups foster nursed to a normal lactating dam (repleted). Daily wt. gain was significantly less in the depleted pups vs. the normal and repleted groups (p < .001). Fibronectin concentrations (ug/ml) were also less in the depleted animals (normal 220.5, repleted 218.0, depleted 151.2). PMNs from depleted pups demonstrated diminished adherence (p < .02) and diminished CR (p < .03) when compared to normal or repleted pups. Thus, PMNs from newborn rats demonstrate diminished ADH and CR following postnatal PCM, which may contribute to increased susceptibility to bacterial infection. Postnatal repletion may restore PMN functional responses.