The present disclosure relates to methods of inducing tolerance to lung allograft transplantation. These methods comprise increasing suppressor CD8.sup.+ T cells and/or suppressing deleterious CD8+ and CD4.sup.+ T cells.

The current invention concerns an isolated mesenchymal stem cell wherein said cell is measuredpositive for mesenchymal markers CD29, CD44 and CD90; and negative for MHC class II molecules,whereinsaid cell secretes immunomodulatory prostaglandin E2 cytokine when present in an inflammatory environment or condition. The current invention also concerns a cell composition comprising said cells and the use thereof in the treatment of immune-related diseases and inflammatory conditions.

A preparation method and applications of rejuvenated and regenerative fibroblasts, where the rejuvenated and regenerative fibroblasts are prepared from normal fibroblasts by inhibiting the JAK-STAT signaling pathway. The rejuvenated and regenerative fibroblasts are prepared by treating the target cells with a small molecular combination, a cytokine combination or a recombinant protein combination. This application further provides an application of the rejuvenated and regenerative fibroblasts in the reprogramming or rejuvenation of cells, tissues, organs and organisms.

Tumor stem cells can be obtained by culturing a tumor cell population, and exposing the cultured tumor cell population to free radicals. In certain embodiments, the free radical agent can be a nitric oxide (NO) donor. In one embodiment, the free radical agent can be Diethylenetriamine NONOate (DETA NONOate) or agents that constitutively increase cellular nitric oxide, such as phosphodiesterase inhibitors or L-arginine, or agents that increase NO synthase in the population. The methods can further include inducing stem cells present in the population to expand and/or inducing dedifferentiation of tumor cells into tumor stem cells. Additionally, the present invention provides methods of selecting stem cells from a tumor cell population. Another aspect provides methods of screening for anti-tumor stem cell teherapeutic compounds by providing high nitric oxide (HNO) tumor cells, exposing the HNO cells to at least one compound, assessing one or more indicators of HNO cell health and determining toxicity of the compound to HNO tumor cells.

A preparation method and applications of rejuvenated and regenerative fibroblasts, where the rejuvenated and regenerative fibroblasts are prepared from normal fibroblasts by inhibiting the JAK-STAT signaling pathway. The rejuvenated and regenerative fibroblasts are prepared by treating the target cells with a small molecular combination, a cytokine combination or a recombinant protein combination. This application further provides an application of the rejuvenated and regenerative fibroblasts in the reprogramming or rejuvenation of cells, tissues, organs and organisms.