Measurement and illustration of immune interaction after stem cell transplantation

A variety of stem cells, including embryonic, mesenchymal, and hematopoietic stem cells, have been isolated to date, resulting in the current investigation of many therapeutic applications. These stem cells offer a high potential in cell replacement therapies or in the regeneration of organ damage. One current obstacle in using these stem cells in clinical applications are the unknown or unexplained mechanisms regarding the activation of immune responses as well as their given potential of immune activity, which can attack the host tissue. Similarly, the unknown immunological environment, which can benefit tumor growth, also restrains the rapid clinical implementation of stem cells. We have shown that several techniques for measurement or illustration of immune responses in a hematopoietic murine CD4(k/o) mice transplantation model might be beneficial to get new insight into in vivo behavior of transplanted stem cells. Subjected to the transplantation setups (allogeneic, syngeneic, or xenogenic transplantation) different immune responses (enhancement of CD4(+) T cells, cytokine activity) as well as different effects of the transplanted cells on the host organs (organ destruction, toxicity) are detectable. The methods used to describe such immune responses will be presented here.