In vitro responses of lymphocytes in juvenile arthritis: effects of time and concentration of PHA-P.

The effects of concentration of PHA-P and time in culture on cells from patients with systemic, polyarticular and pauciarticular juvenile arthritis have been studied. Responses to suboptimal concentrations are depressed at 3 days, particularly of systemic and polyarticular patients, but normal by 5 days and probably prolonged at 7 days. The responses approach normal with 5 micrograms/ml PHA-P. This delay also occurs in cells from children with cystic fibrosis and acute pneumonia and so is not disease specific. Kinetic studies show a slower recruitment of cells. The delay is corrected by 1 microgram/ml indomethacin. After 7 days, cultures from patients with juvenile arthritis have fewer E, heat-stable E, and EAC rosetting cells than do cultures from normal children or children with cystic fibrosis.