METHOD OF HARVESTING MESENCHYMAL STEM CELLS FROM CORD-PLACENTA JUNCTION

Abstract

The present invention is a method of harvesting mesenchymal stem/stromal cells (MSCs) from human umbilical cord/placenta tissue. A key aspect of the invention is that MSCs are harvested from a specific region of the human umbilical cord/placenta, namely, the cord placenta junction (CPJ). In accordance with the method, the tissue is divided into distinct regions, one of which is the cord placenta junction (CPJ). MSCs from the CPJ are isolated and cultured. Harvesting MSCs from the CPJ yields a higher number of cells, with greater proliferation and self-renewal capacities in vitro.

Claims

1. A method of harvesting mesenchymal stem/stromal cells from human umbilical cord/placenta tissue comprising the steps: isolating and dissecting the cord placenta junction from the cord/placenta tissue; cutting the cord placenta junction tissue into sections; and, isolating the mesenchymal stem/stromal cells by explant culturing in a growth medium.

2. The method of claim 1 wherein said sections are substantially square.

3. The method of claim 2 wherein sides of said sections are between 1 and 2 mm.

4. The method of claim 1 wherein duration of said explant culturing step is about 3 or 4 days.

5. The method of claim 1 including the step of removing said mesenchymal stem/stromal cells from said growth medium.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0015] FIG. 1 shows a diagrammatic representation of the method of the invention.

DETAILED DESCRIPTION

[0016] Human umbilical cord (UC) blood and tissue are non-invasive sources of potential stem/progenitor cells with similar cell surface properties as bone marrow stem/stromal cells (BMSCs). However, the UC is an anatomically complex organ and the potential of cells in various sites of the UC has not been fully explored. Commonly dissected regions from the UC to isolate stem cells are cord tissue (CT), Wharton's jelly (WJ) and Fetal Placenta (FP). The idea of separating the cord placenta junction (CPJ) as a distinct anatomical region of the human umbilical cord and isolating the perinatal/mesenchymal stem cells is a key aspect of the invention as will be described in more detail below. In prior art attempts at harvesting MSCs, cells are generally harvested from all regions of the UC. The present invention lies in the discovery that the CPJ is the most potent anatomical region of the UC and yields a higher number of cells, with greater proliferation and self-renewal capacities in comparison to the other sites of the human umbilical cord. Therefore, pre-differentiation of the CPJ derived mesenchymal stem cells into the progenitors of target tissue lineage would pose far greater capacity to regenerate and treat degenerative diseases such as Osteoarthritis and Intervertebral Disc Disease.

[0017] In accordance with the method of the invention the cord/placenta samples 10 are dissected and the CPJ 12 is isolated as can be seen in FIG. 1. The dissected sample 12 is then cut into sections 14. The sections 14 can be square with sides of between 1 to 2 mm.

[0018] The explant culture technique is then used to isolate cells from the CPJ in a suitable growth medium 16. Outgrowth of the cells from the CPJ occur within 3-4 days, and by experimentation it has been discovered that this is faster than cells from the other UC sites. The isolated cells are adherent to plastic and display fibroblastoid morphology and surface markers, such as CD29, CD44, CD73, CD90, and CD105, similarly to bone marrow (BM)-derived MSCs. MSCs from the CPJ differentiate into adipogenic, chondrogenic, and osteogenic lineages, indicating that they were multipotent (as do MSCs from the other sources). However, when compared to MSCs from the other UC sites, as well as (BM)-derived MSCs, experimental data indicates CPJ-MSCs differentiate more efficiently in comparison to other MSC sources. Accordingly, it has been determined that the CPJ is the most potent anatomical region and yields a higher number of cells, with greater proliferation and self-renewal capacities in vitro. A comparative analysis of the MSCs from the four sources indicated that the CPJ is a more promising source of MSCs for cell therapy, regenerative medicine, and tissue engineering.