Isolation and cultivation of neural stem cells from the embryonic rat brain and spinal cord / 生理学报

The aim of this study was to establish the culture system of isolation and cultivation of the neural stem cells (NSCs) from the embryonic rat brain and spinal cord. The methods of microscopic dissection, cell culture and immunofluorescence cytochemistry were used. The results are as follows. (1) In the presence of fibroblast growth factor-2 (FGF-2) and epidermal growth factor (EGF), both brain- and spinal cord-derived stem cells proliferated and expanded in vitro for 8 - 10 passages (over 60 d). The period of expansion resulted in a 10(6)-fold increase in brain-derived NSCs and 10(5)-fold increase in spinal cord-derived NSCs. These proliferating cells expressed nestin. (2) In the medium containing 1% FBS, the two NSCs populations could be induced to differentiate into neurons, astrocytes and oligodentrocytes. The percentage of neurons (beta-tubulin III-ir) differentiated from brain-derived NSCs decreased rapidly from 11.95+/-2.5% at passage 2 (P(2)) to 1.97+/-1.16% at passage 5 (P5). Significant difference was shown between P(2) and P(5) (P<0.01). The percentage of oligodentrocytes (Rip-ir) differentiated from brain-derived NSCs remained mostly unchanged from 8.66+/-2.93% at P(2) to 9.12+/-1.13% at P(5). The same differentiation patterns were found in spinal cord-derived NSCs. All these results indicate that both embryonic rat brain- and spinal cord-derived NSCs can expand and proliferate in vitro through multiple passages, and retain the capacity to differentiate into all three major types of cells in the central nervous system.

Association of HLA-DQB1 coding region with unexplained recurrent spontaneous abortion / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>DNA analysis has shown a lack of significant compatibility between couples affected by unexplained recurrent spontaneous abortion (URSA) compared with normal fertile couples, [8] although one study that made use of a PCR-sequence-specific oligonucleotide (SSO) method did observe evidence of significant compatibility in the HLA-DQA1 and DQB1 alleles between patients and aborted fetuses. [9] This study was designed to investigate whether URSA were associated with particular DQ alleles or promoter alleles.</p><p><b>METHODS</b>Thirty-two patients with URSA and 54 women who had had at least one successful pregnancy were included in this study. HLA-DQ genotyping was performed by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The HLA-DQB1 promoter was detected by the SSO and sequence-specific primer (SSP) methods. The DQA1, DQB1, and DQB1 promoter (QBP) gene frequencies in the patients were compared with the gene frequencies in normal controls. The data were analyzed statistically with the chi(2) and Fisher's exact tests.</p><p><b>RESULTS</b>The results showed that the frequency of DQB1 * 0604/0605 was significantly higher and the frequency of DQB1 * 0501/0502 was significantly lower in the patient group as compared with the normal controls. In addition, the frequencies of the DQA1 * 01-DQB1 * 0604/0605 and QBP6.2-DQB1 * 0604/0605 haplotypes were overrepresented in the patients relative to the controls. Our results did not show any differences between URSA patients and the controls with regard to DQA1 and QBP allele frequencies.</p><p><b>CONCLUSIONS</b>Our data suggest that URSA is associated with the HLA-DQB1 coding region, and is not associated with its upstream regulatory region. The DQB1 * 0604/0605, DQA1 * 01-DQB1 * 0604/0605, and QBP6.2-DQB1 * 0604/0605 haplotypes may confer susceptibility to URSA, while the DQB1 * 0501/0502 allele may protect women from URSA.</p>