Rheumatoid arthritis and osteoarthritis are the main diseases that imply an inflammatory process at the joints
involving the articular cartilage. Recently, mesenchymal stem cells (MSCs) derived from perinatal tissues were considered
good candidates for cellular therapy of musculoskeletal and orthopaedic diseases, since they can differentiate into
multiple cell types and are an easily accessible cellular source. Therefore, several protocols exist on the differentiation of
mesenchymal stem cells of different origins into osteoblasts and chondrocytes. Another key feature of MSCs is their capacity
to modulate the immune system responses in vitro and in vivo. This may have critical outcomes in diseases of the
musculoskeletal system where an inflammatory or autoimmune process is at the basis of the main disease.
In the present paper, after isolation of MSCs from Wharton’s Jelly (WJ-MSCs), we performed the three standard differentiation
protocols. The acquisition of the differentiated phenotype was demonstrated by the specific histological stains. As
the main objective of this work, we determined the expression of immunomodulatory molecules (by immunohistochemistry
and qualitative RT-PCR), both in undifferentiated cells and after differentiation. We demonstrated for the first time
that immune-related molecules (as B7-H3/CD276 and HLA-E) which have been characterized in undifferentiated MSCs,
are also expressed by the differentiated progeny. This strongly suggests that also after the acquisition of a mature phenotype,
WJ-MSCs-derived cells may maintain their immune privilege. This evidence, which deserves much work to be confirmed
in vivo and in other MSCs populations, may provide a formal proof of the good results globally achieved with WJMSCs
as cellular therapy vehicle.