Cord stem-cell transplantation in Ontario: do we need a public bank?

Enumeration of viable CD34+ cells in cord blood using a novel stem cell enumeration kit

OBJECTIVE

To assess the detection performance of the hematopoietic stem cell enumeration kit developed by BD Biosciences.

METHODS

Cord blood samples were prepared using a hematopoietic stem cell enumeration kit developed by BD Biosciences and Stem-Kit reagents from Beckman Coulter. CD34+ cells were enumerated using a BD FACSCanto instrument and FACSDiva software.

RESULTS

A total of 519 samples were analyzed in this study. The hematopoietic stem cell enumeration kit developed by BD Biosciences yielded absolute counts of CD34-positive cells that were on average 8.7% lower than Beckman Coulter Stem-Kit reagents (range: -5.7% to-14.7%). The BD Biosciences kit yielded relative counts that were on average 9.9% higher compared with Beckman Coulter Stem-Kit reagents (range: -2.1% to +13.8%). The intraclass correlation coefficients for absolute and relative counts of CD34-positive cells were 0.9967 (95% confidence interval [CI]: 0.9961-0.9972) and 0.9512 (95% CI: 0.9423-0.9587) for the BD Biosciences and Beckman Coulter kits, respectively.

CONCLUSIONS

The hematopoietic stem cell enumeration kit developed by BD Biosciences can be used to enumerate CD34-positive stem cells from cord blood samples.

Ex Vivo-expanded Natural Killer Cells Derived From Long-term Cryopreserved Cord Blood are Cytotoxic Against Primary Breast Cancer Cells

With over 600,000 units of umbilical cord blood (CB) stored on a global scale, it is important to elucidate the therapeutic abilities of this cryopreserved reservoir. In the advancing field of natural killer (NK) cell cancer immunotherapy, CB has proven to be a promising and noninvasive source of therapeutic NK cells. Although studies have proven the clinical efficacy of using long-term cryopreserved CB in the context of hematopoietic stem cell transplantations, little is known about its use for the ex vivo expansion of effector immune cells. Therefore, our group sought to derive ex vivo-expanded NK cells from long-term cryopreserved CB, using an artificial antigen presenting cell-mediated expansion technique. We compared the expansion potential and antitumor effector function of CB-derived NK (CB-NK) cells expanded from fresh (n=4), short-term cryopreserved (<1-year old, n=5), and long-term cryopreserved (1-10-year old, n=5) CB. Here, we demonstrated it is possible to obtain an exponential amount of expanded CB-NK cells from long-term cryopreserved CB. Ex vivo-expanded CB-NK cells had an increased surface expression of activating markers and showed potent antitumor function by producing robust levels of proinflammatory cytokines, interferon-γ, and tumor necrosis factor-α. Moreover, expanded CB-NK cells (n=3-5) demonstrated cytotoxicity towards primary breast cancer cells (n=2) derived from a triple-negative breast cancer and an estrogen receptor-positive/progesterone receptor-positive breast cancer patient. Long-term cryopreservation had no effect on the expansion potential or effector function of expanded CB-NK cells. Therefore, we propose that long-term cryopreserved CB remains clinically useful for the ex vivo expansion of therapeutic NK cells.

Institutional Knots: A Comparative Analysis of Cord Blood Policy in Canada and the United States

Umbilical cord blood is a rich source of blood stem cells, which are of critical clinical importance in the treatment of a variety of malignant and genetic conditions requiring stem cell transplantation. Many countries have established national public cord blood banks; such banks often coexist with a panoply of private options for cord blood banking. Until recently, Canada was the only G8 country without a national cord blood bank. This differs markedly from the United States, which years ago established a national cord blood bank policy and inventory. This article investigates potential reasons for this discrepancy through a comparative analysis of the evolution of programs and policies on national cord blood banking in Canada and the United States. My analysis suggests that cross-national discrepancies in policy on public cord blood banking were determined primarily by institutional factors, principal among them formal governmental structure and the legacy of past policies. Institutional entrepreneurialism in the health sector played a constitutive role in the earlier evolution of national cord blood policy in the United States as compared to Canada.