Photodynamic therapy (PDT) is mostly used to induce apoptosis or necrosis in benign and malignant tumors, along with other microbial infections and suppression of autoimmune diseases including rheumatoid arthritis (RA). The bone marrow stem (BMS) cells are also a focus in translational medicine, tissue engineering and as an autoimmune disease suppressant. In this study we used tetra sulphonatophenyl porphyrin (TSPP) with TiO₂ nanowhiskers for RA PDT and evaluated the effect on stress biomarkers (CAT, SOD, GPX, GR, TAO and MDA) in vivo and BMS cell proliferation in vitro. We compared four murine groups, three of which had collagen induced arthritis as TP-L (illuminated), TP-nL (dark) and CIA (control), whereas the other group was normal without disease and treatment. All anti-oxidative enzymes and biomarkers were significantly (p < 0.01) affected by the treatment except TAO (p > 0.05). Moreover, we also evaluated the growth proliferation effect of TSPP–TiO₂ (TP) PDT on the in vitro RA infected BMS cells i.e. 25 μl had highest cell count (12.33 × 10⁶ cells per well) and 33% higher growth rate in photoactivated TP when compared with 50 and 100 μl treatment groups. Herein, we report that photoactivated TSPP–TiO₂ for RA PDT may be safer than photosensitizers without the titanium nanomaterials in terms of reduced oxidative stress and also promotion of RA BMS cell growth in vitro as a novel finding.