Stem Cell T Stimulation

Bethesda, Maryland -

The return of ex vivo expanded T cells into an "empty compartment" has been used successfully by Steven Rosenberg and various researchers at the NIH for treatment of cancer. Essentially the idea is that when T cells are placed into a compartment that is lymphodepleted, then the T cells will proliferate by homeostatic expansion and be able to kill targets in absence of second signal.

In a recent study (Wrsesinski et al. Hematopoietic stem cells promote the expansion and function of adoptively transferred antitumor CD8 T cells. J Clin Invest. 2007 Feb;117(2):492-501) it was demonstrated that the efficacy of anti-tumor responses initiated by adoptive transfer of T cells into a lymphodepleted compartment may be substantially augmented by the co-transfer of hematopoietic stem cells.

The authors demonstrate that the hematopoietic stem cells purified from murine bone marrow are capable of providing contact dependent and independent signals that augment T cell antitumor activity independent of antigen presentation.

Watch for new therapeutic regimens to emerge based on these studies that will integrate bone marrow transplantation and autologous T cell immunotherapy.