POSTOPERATIVE IMMUNOLOGICAL FUNCTION AND JAUNDICE

The effects of operative trauma and obstructive jaundice on systemic i mmunity were studied in a rat model, using the delayed-type hypersensi tivity response to 2,4-dinitro-1-fluorobenzene as a measure of systemi c immune responsiveness. Midline laparotomy caused a significant decre ase in the mean(s.e.m.) delayed-type hypersensitivity response 1 week after operation (4.6(1.3) versus 19.0(2.2) per cent for controls). The response returned to control levels by 2 weeks (14.6(3.1) per cent). Common bile duct ligation and division resulted in a significantly dep ressed hypersensitivity response at 2 and 3 weeks (6.8(2.0) and 8.4(1. 6) per cent respectively). The expected decrease in the response at 1 week in these animals was not observed (mean(s.e.m.) 12.7(2.7) per cen t), suggesting a possible role for the normal liver in the induction o f postoperative immune depression. Impaired function of the reticuloen dothelial system was induced in non-jaundiced animals by Kupffer cell ablation following intraportal infusion of Alpha-carrageenan. A simila r prevention of postoperative immune hyporesponsiveness was observed ( mean(s.e.m.) 10.4(1.0) versus 10.4(1.6) per cent for controls). Hepati c Kupffer cells play an important role in the induction of postoperati ve immune depression.