Application of paracrine effect of fallopian tube stem cells derived from Holstein cattle to bovine mastitis

Objective Mastitis in dairy cows is a major cause of economic loss, and conventional antibiotic treatments often result in antimicrobial resistance and increased milk discard. This study aimed to evaluate bovine fallopian tube-derived stem cells as a novel source of mesenchymal stem cells (MSCs) and to investigate the therapeutic potential of their conditioned medium (C-DPBS) in mastitis treatment. Materials and methods Bovine fallopian tubes, typically discarded after slaughter, were used as a source of stem cells. Isolated cells were characterized by analyzing cell surface markers and assessing their multilineage differentiation potential in vitro. Expression of MSC-associated markers and hematopoietic lineage markers was evaluated. Differentiation assays were conducted to confirm osteogenic and adipogenic potential. Additionally, the therapeutic efficacy of conditioned Dulbecco's phosphate-buffered saline (C-DPBS) was assessed in mastitis-affected cows by monitoring somatic cell counts (SCC) over time and comparing results with a conventional antibiotic treatment group. Results The isolated cells exhibited MSC-like characteristics, including high expression of CD44 (72.5%) and low expression of CD4 (2.0%) and CD105 (1.3%), with no hematopoietic marker expression. The cells successfully differentiated into osteoblasts and adipocytes. In the mastitis treatment trial, 66% of cows in the antibiotic-treated group and 46% in the C-DPBS group reached the milk collection threshold by Day 8. SCC in the C-DPBS group was significantly reduced on Day 8 compared to Day 0 (P < 0.05), with no significant difference between the antibiotic and C-DPBS groups (P > 0.05). The antibiotic group also showed a significant reduction in SCC on Day 8 compared to Days 0–3 (P < 0.05). Conclusion Bovine fallopian tube-derived stem cells exhibit MSC properties and multilineage differentiation potential. Their conditioned medium (C-DPBS) effectively reduces somatic cell counts, indicating its potential as an alternative therapeutic approach for mastitis management in dairy cows.