Comparison of infrapatellar and subcutaneous adipose tissue stromal vascular fraction and stromal/stem cells in osteoarthritic subjects.
Since inflammatory mechanisms have been postulated to link obesity to osteoarthritis, the current study evaluated the ratio of immune cells to multipotent stromal cells within the infrapatellar fat pad (IPFP) and subcutaneous adipose tissue (SQ) of the knee; each depot has potential as a source of regenerative cells. The immunophenotypes of stromal vascular fraction (SVF) and adipose-derived stem cells (ASCs) of the IPFP and SQ were determined in tissues from osteoarthritic subjects (n = 7) undergoing total knee replacement. Based on a subset of surface antigens, the immunophenotype of ASCs from SQ of OA subjects was not significantly different from that of relatively healthy and leaner subjects undergoing elective liposuction surgery. Flow-cytometry comparison of SVF cell populations in the IPFP of OA subjects resembled those within the subject's own matched SQ, with the exception of the endothelial marker CD31(+) , which was significantly greater in cells from SQ. In the OA subjects, lower numbers of capillary-like structures and higher numbers of stromal and alkaline phosphatase colony-forming units in the IPFP vs SQ were consistent with this finding; however, ASCs from both depots in OA subjects exhibited comparable adipogenic and osteogenic differentiation potential. Thus, the IPFP contains an ASC and immune cell population similar to that of donor-matched SQ, making it an alternative ASC source for tissue regeneration. Further studies will be needed to determine whether IPFP immune cell infiltrates play an aetiological role in osteoarthritis equivalent to that shown in diabetes associated with obesity.
Pennington Biomedical Research Center, 6400 Perkins Road, Baton Rouge, LA, USA; 3Bs Research Group, Biomaterials, Biodegradables and Biomimetics, University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine, Avepark, Guimarães, Portugal; ICVS/3Bs PT Government Associated Laboratory, Braga/Guimarães, Portugal.
Pedro
P
Pires de Carvalho
Katie M
KM
Hamel
Robert
R
Duarte
Andrew G S
AG
King
Masudul
M
Haque
Marilyn A
MA
Dietrich
Xiying
X
Wu
Forum
F
Shah
David
D
Burk
Rui L
RL
Reis
Jennifer
J
Rood
Ping
P
Zhang
Mandi
M
Lopez
Jeffrey M
JM
Gimble
Vinod
V
Dasa
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee; D042783:Endothelial Cells / Q000378:metabolism / Q000473:pathology; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D008297:Male; D059630:Mesenchymal Stem Cells / Q000378:metabolism / Q000473:pathology; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000378:metabolism / Q000473:pathology; D019408:Platelet Endothelial Cell Adhesion Molecule-1 / Q000378:metabolism; D039904:Pluripotent Stem Cells / Q000378:metabolism / Q000473:pathology; D050151:Subcutaneous Fat / Q000378:metabolism / Q000473:pathology
D019408:Platelet Endothelial Cell Adhesion Molecule-1