AIM: To elaborate optimal cell culture administration regimens to enhance the 
efficiency of anti-inflammatory therapy for inflammatory bowel diseases.
SUBJECTS AND METHODS: Three groups of patients with chronic continuous or 
chronic recurrent ulcerative colitis (UC) were formed according to the treatment 
option: 1) 15 patients with UC, in whom mesenchymal stromal cells (MSC) were 
thrice administered for a month at a one-week interval; 2) 20 patients with UC 
who received MSC once; 3) 20 patients with UC who had standard anti-inflammatory 
therapy with 5-aminosalycilic acid (5-ASA) preparations and glucocorticosteroids 
(GCS). The clinical activity of UC was evaluated using the Rachmilewitz index; 
its endoscopic pattern was assessed with the Mayo index. UC histological 
specimens were scored using the Gebs scale. To ascertain the duration of 
remission, the authors used the Kaplan-Maier survival curve method and 
calculated relative risk (RR) and odds ratio with 95% confidence intervals.
RESULTS: Following 12 months, allogeneic bone marrow (BM) MSC transplantation 
performed thrice during a month caused the greatest reduction in the 
Rachmilewitz clinical activity index, Mayo endoscopic activity index, and Gebs 
pathohistological index in patients with UC as compared to those who had 
underwent one transplantation or received 5-ASA preparations and GCS (p < 0.05). 
The duration of remission also depended on the chosen therapy option for UC and 
the frequency of cell culture administration: the longer duration was recorded 
in patients who were infused thrice with allogeneic BM MSC.
CONCLUSION: In the patients who had undergone one MSC administration, the risk 
of recurrent UC was higher than in those who had received MSC thrice during a 
month (a 2-year follow-up) and comparable with the RR of recurrent UC in the 
patient receiving only 5-ASA preparations, GCS, and/or immunosuppressants.