Fig. 4

Immune cell fraction from APS treatment persists in RAG KO OA model. Ten-week female C57BL/6 RAG KO mice underwent unilateral ACLT surgery and treatment 2 weeks later with saline (control), human APS, APS without cellular component (denoted as APS w/o cell), sorted CD3⁺ cells from APS (denoted as CD3⁺ or APS-CD3⁺ only), or sorted CD45⁺ cells from APS (denoted as CD45⁺ or APS-CD45⁺ only) (n = 5/group), and no surgery (N.S.) control. a Study design. b Average response time after treatment. Percentage of weight placed on the operated limb versus the contralateral control limb (data are mean with ± SEM). c Representative brightfield images of safranin-O fast green staining of joint (× 20 magnification). Scale bar = 200 μm. d Immunofluorescence staining of human CD4⁺ cells (pink) that does not react with mouse and DAPI counterstain (blue) in the synovium of the operated joints 2 weeks after injection with APS, APS without cellular component, CD3⁺ sorted from APS, CD45⁺ sorted from APS, saline, and no surgery (N.S.) control (× 20 magnification). Scale bar = 200 μm for joint and for zoomed-in ROI scale bar = 20 μm. Ordinary one-way ANOVA with Tukey’s multiple comparison tests for b. *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001