The written consent of the subjects will be obtained after full information of the aims, nature and possible risks of the study.~Before inclusion, subjects will undergo a medical check-up including an interview on personal and family history and drug treatments taken as well as a standard medical examination including weight, height and blood pressure measurement. . Their compliance with the inclusion / exclusion criteria will be verified during this review. An interview with personnel involved in the research (a dietician / study Research clinic assistant, etc.) will also be carried out as well as a biological selection assessment.~As part of this study, the subjects will come a total of 7 times to the Emile ROUX hospital in Le Puy en Velay.~The probiotic treatment will begin between 1 and 3 weeks after the inclusion visit. The volunteers / patients recruited will have a volume of blood sampled and a stool collected before the start of the probiotic treatment (T = 0) and at the end of the treatment (T = 4 weeks). The study consists of three periods of probiotic treatment of 4 weeks each interspersed with a wash-out period of 3 weeks in accordance with the recovery period necessary between two blood samples.~The sera thus obtained will then be analyzed to determine their biological activity with regard to the induction of changes in the behavior of bone cell models: osteoformin cells (osteoblasts) and osteo-resorbent cells (osteoclasts).
The main objective of the study is to determine the influence of patient sera before and after probiotic intervention on the behavior of bone cells (osteoblasts and osteoclasts).~The secondary objectives are to assess the activity of bone cells and the course of rheumatoid arthritis before and after the consomption of probiotics.