Fig. 2

Irradiation in combination with thymectomy enhances chronic arthritis. a Rats were pre-conditioned by irradiation and/or thymectomy (as indicated in the enclosed table) prior to transfer. Left: arthritis development in rats transferred with or without LN-derived cells. Right: summary data of total incidence (Incid), incidence of arthritis lasting > 40 days (Chronic), and level of acute-phase protein (AGP). Number of rats per group is indicated in the enclosed table. b Immunohistochemistry of hind paws from rats shown in a stained for CD4⁺ cells, macrophages and neutrophils. Bottom tables show quantifications (as percent of total cells) of infiltrating cell populations; 0.5 to 5% (++), 5 to 20% (+++), or 20 to 50% (++++). c Irradiated/thymectomized rats (n = 70) were transferred with T cells as in a. On day 65 post-transfer, rats were divided into three disease-matched groups that were treated with methotrexate (n = 9), etanercept (n = 9), or phytol (n = 8). Filled and open circles represent normalized disease scores (vs. day 65) for treated and none-treated individuals, respectively. Statistical analyses as in Fig. 1. All groups in a were compared to non-irradiated, non-thymectomized rats except those indicated by a hash sign (#), which were compared to irradiated, non-thymectomized recipients. Data shown in c were pooled from two separate experiments