Stem cell properties and neural differentiation of sheep amniotic epithelial cells

This study was designed to verify the stem cell properties of sheep amniotic epithelial cells and their capacity for neural differentiation. Immunofluorescence microscopy and reverse transcription-PCR revealed that the sheep amniotic epithelial cells were positive for the embryonic stem cell marker proteins SSEA-1, SSEA-3, SSEA-4, TRA-1-60 and TRA-1-81, and the totipotency-associated genes Oct-4, Sox-2 and Rex-1, but negative for Nanog. Amniotic epithelial cells expressed β-Ⅲ-tubulin, glial fibrillary acidic protein, nestin and microtubule-associated protein-2 at 28 days after induction with serum-free neurobasal-A medium containing B-27. Thus, sheep amniotic epithelial cells could differentiate into neurons expressing β-Ⅲ-tubulin and microtubule-associated protein-2, and glial-like cells expressing glial fibrillary acidic protein, under specific conditions.

Construction and Immunogenicity of a Recombinant Adenovirus Expressing the HA Gene of H5N1 Subtype Swine Influenza Virus

To construct a recombinant adenovirus shuttle plasmid pDC315-H5HA-EGFP,the HA gene of A/Swine/Fujian/1/2001(H5N1) was amplified by RT-PCR and then inserted into adenovirus shuttle plasmid pDC315.A replication-defective recombinant adenovirus expressing the HA gene(rAd-H5HA-EGFP) was generated by co-transfecting the recombinant shuttle plasmid pDC315-H5HA-EGFP and the genomic plasmid pBHGlox△E1,E3Cre in HEK293 cells.The recombinant adenovirus was confirmed by PCR,RT-PCR and Western blot assay.These results demonstrated that HA protein was properly expressed by the rAd-H5HA-EGFP in HEK293 cells and had natural biological activities.The TCID50 of the rAd-H5HA- EGFP was assessed to be 2.26×1010/mL after propagation and purification.Immunization of BALB/ c mice indicated that rAd-H5HA-EGFP induced HI antibodies and protected mice from replication of the challenge virus in their lungs.