Comparison of Residual Dimethyl Sulfoxide (DMSO) and Ethylene Glycol (EG) Concentration in Bovine Ovarian Tissue During Warming Steps Between Slow Freezing and Vitrification.

BACKGROUND: DMSO and EG have been used as cryoprotectants for human ovarian tissue cryopreservation, but residual cryoprotectants concentration and safety have rarely been reported. OBJECTIVE: We aimed to compare residual cryoprotectants (DMSO, EG) concentration in bovine ovarian tissue during warming steps between one kind of common slow freezing method and two kinds of vitrification methods, which are usually used for cryopreservation of human ovarian tissue in Japan. MATERIALS AND METHODS: In this study, we used five bovine ovaries with an average age of 24.2 months divided into three kinds of cryopreservation methods. All ovarian cortices cut to 1 mm thickness were cryopreserved in slow freezing and two kinds of vitrification methods. Residual cryoprotectants before, during and after warming of cryopreserved ovarian cortices were measured using GC-MS and compared. RESULTS: Concentrations of residual cryoprotectants in the ovarian tissue just before transplantation into the body after warming were high after both vitrification methods but almost zero with the slow freezing method. CONCLUSION: We are concerned about the residual cryoprotectants in ovarian tissue, and continue to study the safety of cryopreservation methods to the woman after reimplantation and her baby.

Maternal inheritance of atopic IgE responsiveness on chromosome 11q.

Atopy is a common familial state underlying allergic asthma and rhinitis. Lately, we have assigned a gene for atopy to chromosome 11q by linkage to the marker D11S97. Since previous studies have suggested that the risk of atopy is higher for children of atopic mothers than for those of atopic fathers, we sought differences between maternal and paternal patterns of transmission at the 11q13 locus among pairs of siblings in families affected by atopy. When we defined atopy as the presence of a positive skinprick test (greater than or equal to 2 mm) to any of a panel of common allergens, a higher than normal concentration of total serum IgE, or a positive radioallergosorbent test for a specific IgE, we found that 125 (62%) of the sibling-pairs affected by atopy shared the maternal 11q13 allele and 78 (38%) did not. This distribution differs significantly from the expected 50/50 distribution (p = 0.001). Of paternally derived alleles, 83 (46%) were shared and 96 (54%) were not (not significantly different from 50/50). The result was similar whatever definition of atopy was used and with other genetic markers on 11q. These findings show that transmission of atopy at the chromosome 11q locus is detectable only through the maternal line. The pattern of inheritance is consistent either with paternal genomic imprinting or with maternal modification of developing immune responses.