Abstract

The adult human body is composed of trillions and trillions of cells. These cells can be divided into three categories: functional differentiated cells, maintenance progenitor stem cells, and healing stem cells. Healing stem cells were discovered in 1975 residing within niches in the connective tissues of adult terrestrial salamanders undergoing complete limb regeneration. Since 1975, healing stem cells and maintenance progenitor stem cells have undergone extensive comparison and contrast analyses. The healing stem cells are uniquely different from maintenance progenitor stem cells. Healing stem cells are telomerase positive which gives them an essentially unlimited proliferation potential. Maintenance progenitor stem cells are telomerase negative, thus having a defined lifespan before pre-programmed senescence and cell death. In toto, healing stem cells will form all the somatic cells of the body, gametes, and the nucleus pulposis of the intervertebral disc. Maintenance progenitor cells will only form somatic cells within their respective cell lineages. The first report described a high throughput screening-assay, termed ELICA, to assess the differentiation potential of proliferative, progressive, inductive, and anti-differentiative biological agents on healing stem cells and maintenance progenitor cells. The second report introduced endogenous healing stem cells and described their location in the body. The third report described the methodologies developed to optimize the viability of mixed cultures of cells of differentiated cells, maintenance progenitor cells and healing stem cells during their isolation, segregation, plating, and propagation. This report describes in detail the separation of the mixed cultures of functional differentiated cells, maintenance progenitor stem cells, and healing stem cells based on differential centrifugation, cell surface markers, and cell sorting.

Keywords

differentiated cells, progenitor cells, stem cells, telomerase, differential centrifugation, cd markers, cell sorting