Masato Senoo

Reversal of Hypopigmentation in Phenylketonuria Mice by Adenovirus-Mediated Gene Transfer

Phenylketonuria (PKU) is caused by deficiency of phenylalanine hydroxylase (PAH) in the liver. Patients with PKU show increased L-phenylalanine in blood, which leads to mental retardation and hypopigmentation of skin and hair. As a step toward gene therapy for PKU, we constructed a replication-defective, E1/E3-deleted recombinant adenovirus harboring human PAH cDNA under the control of a potent CAG promoter. When a solution containing 1.2 × 109 plaque-forming units of the recombinant adenovirus was infused into tail veins of PKU model mice (Pahenu2), predominant expression of PAH activity was observed in the liver. The gene transfer normalized the serum phenylalanine level within 24 h. However, it also provoked a profound host immune response against the recombinant virus; as a consequence, the biochemical changes lasted for only 10 d and rechallenge with the virus failed to reduce the serum phenylalanine concentration. Administration of an immunosuppresant, FK506, to mice successfully blocked the host immune response, prolonged the duration of gene expression to more than 35 d, and allowed repeated gene delivery. We noted a change in coat pigmentation from grayish to black after gene delivery. The current study is the first to demonstrate the reversal of hypopigmentation, one of the major clinical phenotypes of PKU in mice as well as in humans, by adenovirus-mediated gene transfer, suggesting the feasibility of gene therapy for PKU.

Age-specific incidences of chromosome abnormalities at the second trimester amniocentesis for Japanese mothers aged 35 and older: collaborative study of 5484 cases.

AbstractThe aim of this study was to calculate the expected incidences of chromosome abnormalities found at amniocentesis in Japanese women aged 35 and older. From four clinics in Japan, we gathered genetic amniocentesis data on 5484 pregnant women at risk only due to their advanced age, 35 years and older. We analyzed the data using the logistic regression model. Of the 5484 fetuses, 117 (2.1%) were diagnosed with a chromosome abnormality. The abnormal karyotypes included 42 cases of trisomy 21; 13 of trisomy 18; 7 of trisomy 13; 10 of 47,XXY; 4 of 47,XXX; 1 of 47,XYY; 27 with various structural aberrations; and 13 with various types of mosaicism. The incidences of trisomy 21, lethal autosomal aneuploidies (trisomy 18 and trisomy 13), and sex-chromosome abnormalities (XXY, XXX, XYY) increased with maternal age. Parameters of the regression equations with their standard errors were calculated and the expected incidences of chromosome abnormalities at each maternal age were derived. The expected incidences of chromosome abnormalities obtained in this study are the first data published for Japan and will be useful for the counseling of pregnant women. The incidence of trisomy 21 is not different from the rates published previously for Western countries. The incidences of chromosome abnormalities are not affected by race or by geographic factors.

Decrease and senescence of endothelial progenitor cells in patients with preeclampsia

BACKGROUND In preeclampsia, the precise mechanism of impaired vascular function is still unclear. We hypothesized that cellular function of circulating endothelial progenitor cells (EPCs) might be impaired in patients with preeclampsia. OBJECTIVE The objective of this study was to investigate the number and status of cellular senescence of EPCs in the circulation of women with preeclampsia. METHODS Circulating EPCs were cultured from patients with preeclampsia (n = 8) and normotensive pregnant women (n = 7). EPC numbers were assessed by colony-forming unit (CFU) methodology as previously reported. In addition, to assess cellular senescence, we measured endogenous beta-galactosidase activity. Moreover, we assessed whether the serum level of C-reactive protein (CRP), a marker for systemic inflammation, was associated with cellular impairment of EPCs. RESULTS The number of circulating EPCs was decreased in women with preeclampsia controls (median, 10.0 vs. 34.0 CFU; P < 0.01). The rate of cellular senescence was significantly increased in patients with preeclampsia (33.9%) compared with that in controls (22.9%; P < 0.05). Patients with preeclampsia were divided into two subgroups: the CRP-negative group (CRP, <0.1 mg/dl; n = 4) and the CRP-positive group (CRP, > or =0.1 mg/dl; n = 4). Interestingly, EPC CFU counts were markedly decreased in CRP-positive patients compared with those in CRP-negative patients (5.0 and 25.0 CFU, respectively; P < 0.05). Median values for cellular senescence were greater in the CRP-positive group than in the CRP-negative group, although this did not achieve statistical significance (43.5% and 33.3%, respectively; P = 0.12). CONCLUSION Depletion and cellular aging of EPCs in patients with preeclampsia might be associated with endothelial dysfunction and could be affected by systemic inflammation.