Histological changes in the knee joints of animals with collagen-induced arthritis. Semiquantitative scoring of the histological changes in the knee joints of the animals with collagen-induced arthritis (CIA) and either the normal diet (N) or the phosphatidylcholine-enriched diet, starting either with the CIA induction (PCpre) or with the clinical onset of the disease (PCther). For the induction of CIA, animals were immunized twice with collagen II and complete Freund's adjuvant/incomplete Freund's adjuvant. Three weeks after the second immunization, the knee joints were removed, decalcified, sectioned and stained, as described in Materials and methods. Values given as medians with the 25th and 75th percentiles. $P < 0.05 versus N/control.