Cell therapy is thought to be the ultimate treatment for degenerative disease and cancer. Stem cells or progenitor cell transplantation will replace those damaged cells or tissue, because stem cells are immature, un-differentiated cells that have potential to produce a variety of cells in our body. The majority of stem cell therapy options (embryonic stem cell, patient specific induced pluripotent stem cells, neural stem cells and mesenchymal stem cells) are still in animal experimental or pre-clinical stage. Currently, only hematopoietic stem cells (HSCs) are used in the clinic to treat patients with cancer, blood or immune defects. High quality hematopoietic stem cells can be purchase from HemaCare.
Hematopoietic stem cells (HSCs) are multipotent, self-renewing progenitor cells which can form different types of blood and immune cells. During hematopoiesis, HSCs can give rise to cells of the erythroid, lymphoid and myeloid lineages. Daily they produce billions of new blood cells, B and T cells for the body.
HSCs are originally isolated from bone marrow in the early 1960s, and it is the only type of stem cells has been used in cell therapy to reconstitute blood cells and restore the immune system. But the risk is high and the efficiency is low. To improve the efficiency and decrease risk, it is important to understand the regulators for HSCs proliferation or renewal.
Recently, Nakada et al. reported that estrogen increases HSC proliferation and HSCs from female mice divide more frequently than those from male mice . But the basal number of the HSCs in the bone marrow and spleen remained the same meaning that the cell death of those newly generated HSCs in female is also higher compared to males.
This study highlighted an interesting phenomenon; that the difference between male and female was involved in the HSC proliferation. So far there are very few studies that address how the sex differences will affect in cell therapy. It has been shown in mice that stem cell derived from female have higher muscle regeneration efficiency than male  .This evidence may push researchers to take sexual dimorphism into consideration in the future cell therapy research.
 Nakada, D., H. Oguro, et al. (2014). "Oestrogen increases haematopoietic stem-cell self-renewal in females and during pregnancy." Nature 505(7484): 555-558.
 Leeman, D. S. and A. Brunet (2014). "Stem cells: Sex specificity in the blood." Nature 505(7484): 488-490.
Deasy, B. M., A. Lu, et al. (2007). "A role for cell sex in stem cell-mediated skeletal muscle regeneration: female cells have higher muscle regeneration efficiency." J Cell Biol 177(1): 73-86.