Miwako Kikuchi | PubMed Health

PubMed2003

A simple controlled-rate freezing method without a rate-controlled programmed freezer provides optimal conditions for both large-scale and small-scale cryopreservation of umbilical cord blood cells.

BACKGROUND: Umbilical cord blood (CB) is being used as a source of alternative HPCs for transplantation with increasing frequency. The goal of CB banks for unrelated transplantation is to provide good quality-controlled CB units that can be transplanted for HPCs into the largest possible number of patients. STUDY DESIGN AND METHODS: Large CB samples in freezing bags wrapped with insulators and small samples in cryotubes placed into double styrene-foam boxes were cryopreserved at -85 degrees C without a rate-controlled freezing machine, followed by storage in the liquid phase of nitrogen. After thawing these cells, the viability and recovery of cells, as well as the recovery rate of HPCs such as CD34+ cells, CFU-GM, and total CFU were evaluated. RESULTS: Measurement of the freezing rate in CB bags and cryotubes demonstrated that this simple method for cryopreservation of CB cells provided optimal conditions for both large-scale and small-scale cryopreservation. Recovery of CB progenitor cells after cryopreservation was also shown to be potentially acceptable when evaluated with CD34+ cells, CFU-GM, and total CFU. These results were comparable to the method using a rate-controlled programmed freezer. CONCLUSIONS: A simple method for cryopreservation of CB cells without a rate-controlled programmed freezer could provide a sufficient-enough potential for the transplantability of HPCs after thawing.

Blood Banks↗

PubMed2002

Delayed recovery of effector memory CD4+ T cells by highly active antiretroviral therapy in a patient with HIV-1 infection.

Effector memory T cells, which are potentially important in the protection against various pathogens, have been shown to be CCR7 negative. We report a case with HIV-1 infection in whom the change in the cell numbers of the subsets of CD4+ T cells, including CCR7 negative memory CD4 + T cells, in peripheral blood was monitored for more than one year after the initiation of highly active antiretroviral therapy. Percentage of each subsets in lymphocytes was measured by triple staining on lymphocyte fraction in flow-cytometry. The numbers of total CD4+ T cell, naive T cells, and CCR7 positive memory T cells successfully increased within half a month after the initiation of the therapy. Instead, the recovery of the cell number in CCR7 negative memory T cells delayed, and continued to increase untill 10 months after the initiation of the therapy. It suggests the possibility of delay in recovery of immune systems after the initiation of the therapy in HIV-1-infected patients, despite the prompt recovery of total CD4 + T cells.

Adult↗