Stem cell therapy in the management of shoulder rotator cuff disorders

Table 1 Main biochemical and histological characteristics of the four areas of the enthesis[28]

Zone	Histological characteristics	Collagen type	Extracellular matrix composition
Zone 1	Tendon	I	Decorin
Zone 2	Non-mineralized fibrocartilage	II and III ( small amounts of I, IX and X)	Aggrecan and decorin
Zone 3	Mineralized fibrocartilage	II (small amounts of X)	Aggrecan and mineral component
Zone 4	Bone	I	Mineral component

Table 2 Rotator cuff repair animal models using mesenchimal stem cells

Ref.	Animal	Type of cells	Tendon repair model	Method of delivery	Results
Gulotta et al[20]	Rat	Allogenic BM-MSC	Supraspinatus tendon Acute repair	Fibrin glue carrier	No differences in structure, composition or strength at the repair site
Gulotta et al[63]	Rat	Allogenic BM-MSCs transduced with MT1- MMP	Supraspinatus tendon Acute repair	Fibrin glue carrier	Improved fibrocartilage Improved biomechanical strength
Gulotta et al[64]	Rat	Allogenic BM-MSCs transduced with human BMP-13	Supraspinatus tendon Acute repair	Fibrin glue carrier	No differences in structure, composition or strength at the repair site
Gulotta et al[65]	Rat	Allogenic BM-MSCs transduced with sleraxis	Supraspinatus tendon Acute repair	Fibrin glue carrier	Improved fibrocartilage Improved mechanical resistance and stiffness
Shen et al[74]	Rabbit	Allogenic T-MSCs	Supraspinatus tendon Acute repair	Seeded scaffold (silk-collagen)	T-MSCs differentiated into tenocytes Improved collagen content Improved biological environment Less inflammation
Kida et al[62]	Rat	Autologous BM-MSC	Supraspinatus tendon Acute repair	Transosseous drilling	BM-MSCs infiltrated the repaired tendon Improved mechanical resistance
Oh et al[71]	Rabbit	Allogenic A-MSCs	Subscapularis tendon Chronic repair	Injection	Improved muscle function Improved tendon healing Decreased fatty infiltration

Different types of cells have been used: Bone marrow derived MSCs (BM-MSCs), Tendon derived MSCs (T-MSCs) or Adipose derived MSCs (A-MSCs). MT1-MMP: Metalloproteinase inhibitor-1; BMP-13: Bone morphogenetic protein-13; MSCs: Mesenchymal stem cells.