title: The influence of long-term protein deprivation on in vivo phagocytic cell delivery to inflammatory lesions.
abstract: The effect of long-term protein deprivation and refeeding was assessed on the in vivo delivery of phagocytic leukocytes (PHAGS) to delayed-type hypersensitivity (DTH) reaction and a bacterial abscess. Male inbred Lewis rats sensitized to keyhole limpet hemocyanin (KLH) were fed either a normal diet or a 2% protein diet for 1, 6, and 10 weeks. Two additional groups were fed a 2% protein diet for 10 weeks but were refed with a normal diet for 1 or 4 weeks. At the end of each diet period rats were injected intradermally with KLH, Staphylococcus aureus 502A, and saline solution at different sites at from 1 to 24 hours. Technetium-99m-colloid labeled PHAGS (99PHAG) were injected intravenously and used to assess in vivo PHAG cell delivery. In normally fed rats the peak influx of 99PHAG was at 2 to 4 hours. After 1 week of protein-deficient diet there was a significant drop in early (2 to 4 hours) 99PHAG influx to both the DTH and bacterial reactions. After 10 weeks of protein deprivation (severe malnutrition) there was a further drop and a delay in the peak 99PHAG influx (from 2 to 4 hours, to 8 hours). A return to normal 99PHAG influx occurred only after 4 weeks of refeeding, and it coincided with a return to normal body weight and a normal DTH reaction. There was a direct correlation between total 99PHAG delivery to a DTH reaction and a bacterial abscess (rs = 0.87, Spearman rank; p less than 0.001). We conclude that both moderate and severe protein deprivation is associated with reduced in vivo phagocytic cell delivery to both a DTH reaction and a bacterial skin abscess, which can be restored with refeeding.
mesh_terms: D000038:Abscess / Q000276:immunology*; D000818:Animals; D006968:Hypersensitivity, Delayed / Q000276:immunology*; D008297:Male; D010586:Phagocytes / Q000276:immunology*; D011502:Protein-Energy Malnutrition / Q000276:immunology*; D051381:Rats; D011917:Rats, Inbred Lew; D012874:Skin Diseases, Infectious / Q000276:immunology*; D012882:Skin Tests; D013203:Staphylococcal Infections / Q000276:immunology*; D013997:Time Factors