Allogenic Umbilical Cord Mesenchymal Secretome for Knee Osteoarthritis: A Clinical Efficacy, Imaging and Safety Study - Soetjahjo, Bintang; Hancoro, Udi; Ermawan, Rieva; Saputra, Rhyan; Adriansyah, Denny (International Journal of Hematology-Oncology and Stem Cell Research, 2026)