Fate and protective effect of marrow stromal cells after subretinal transplantation

Safety and immunomodulatory effects of allogeneic canine adipose-derived mesenchymal stromal cells transplanted into the region of the lacrimal gland, the gland of the third eyelid and the knee joint

BACKGROUND AIMS

Mesenchymal stromal cells (MSCs) have been extensively studied as a cellular therapeutic for various pathologic conditions. However, there remains a paucity of data regarding regional and systemic safety of MSC transplantations, particularly with multiple deliveries of allogeneic cells. The purpose of this study was to investigate the safety and systemic immunomodulatory effects of repeated local delivery of allogeneic MSCs into the region of the lacrimal gland, the gland of the third eyelid and the knee joint in dogs.

METHODS

Allogeneic adipose tissue-derived canine MSCs were delivered to the regions of the lacrimal gland and the third eyelid gland as well as in the knee joints of six healthy laboratory beagles as follows: six times with 1-week intervals for delivery to the lacrimal gland and the third eyelid gland regions and three to four times with 1- to 2-week intervals for intra-articular transplantations. Dogs were sequentially evaluated by clinical examination. At the conclusion of the study, dogs were humanely euthanized, and a complete gross and histopathologic examination of all organ systems was performed. Mixed leukocyte reactions were also performed before the first transplantation and after the final transplantation.

RESULTS

Clinical and pathologic examinations found no severe consequences after repeated MSC transplantations. Results of mixed leukocyte reactions demonstrated suppression of T-cell proliferation after MSC transplantations.

CONCLUSIONS

This is the first study to demonstrate regional and systemic safety and systemic immunomodulatory effects of repeated local delivery of allogeneic MSCs in vivo.

Differentiation of mesenchymal stem cell in the microenviroment of retinitis pigmentosa

CORRESPONDENCE TO: Fang-Tian Dong. Department of Ophthalmology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing 100730, China. d_fangtian@sina.com

AIM

To access the differentiation of rat mesenchymal stem cell (MSC) in the microenvironment of retinal degeneration induced by the administration of sodium iodate.

METHODS

In-vitro cultured Lewis rat MSC were injected into the sub-retinal space of NaIO(3) induced retinal degeneration rat eyes (30g/L NaIO(3) 100mg/kg). To observe the trace and differentiation of MSC by immuno-fluorescent method successively in 5 weeks after the surgery.

RESULTS

The majority of the transplanted cells stay in retinal pigment epithelium layer and cones & rods layer. From the 2(nd) week after transplantation, the engrafted MSC express PCK and rhodopsin under fluorescent microscope.

CONCLUSION

MSC can survive mainly in the outer layer of retina in the microenvironment of retinal degeneration and differentiate forward the RPE cell and photoreceptor.