Enrichment of haploid spermatids in mice by flow sorting / 中华男科学杂志

<p><b>OBJECTIVE</b>To establish an effective method for haploid spermatid enrichment by Hoechst 33342 staining and flow sorting.</p><p><b>METHODS</b>Mouse testicular monoplast suspension was prepared by two-step enzyme digestion, and the cells were incubated in the medium containing Hoechst 33342 and Verapamil. Haploid spermatids were separated and enriched according to their DNA content by flow sorting. The gene expressions in the spermatids of several histone-modified enzymes, including the histone acetylases (HAT) and histone deacetylases (HDAC), were examined by RT-PCR and compared with that in the HAT-inhibitor curcumin-treated counterparts.</p><p><b>RESULTS</b>We successfully enriched the haploid spermatids with high purity and further purified the round and elongated spermatids. RT-PCR results indicated the specificity of the expression of the HAT gene in the spermatids, and that it was influenced by curcumin.</p><p><b>CONCLUSION</b>Flow sorting can efficiently improve the purity of haploid spermatid enrichment, which helps a lot to elucidate the mechanisms of spermiogenesis.</p>

A proliminary study on the regulatory function of human plasma exosomes-like vesicles / 中华血液学杂志

<p><b>OBJECTIVE</b>To identify the exosomes-like vesicles from the plasma and study their biologic characteristics and regulatory effect.</p><p><b>METHODS</b>The exosomes-like vesicles were purified from healthy donors plasma with a series of high-speed centrifugations and ultrafiltration. Morphology was identified by transmission electron microscopy and biologic characteristics by Western blot and flow cytometry. CD4(+)T cells and CD4(+)CD25(+)CD127low Treg cells were purified from peripheral blood mononuclear cells (PBMCs) by Magnetic cell sorting. After exosomes-like vesicles cultured with CD4(+)T cells or CD4(+)CD25(+)CD127low Treg cells, cell proliferation and apoptosis were assayed. Phosphorylated β-catenin level in Wnt signaling by phosflow.</p><p><b>RESULTS</b>Exosomes-like vesicles from plasma were similar to previously described exosomes in shapes and size and expressed exosome marker proteins CD63 and CD81 as well as the MHC-II molecule, costimulatory molecules CD86 etc. After co-cultured with CD4(+) T cells, exosomes-like vesicles inhibited the proliferation of the T cells in a dose-dependent manner. After Treg cells cultured with exosomes-like vesicles for 14 days, the survival rate of the Treg cells was 57.07%, while that of the control Treg was 30.91%. Frizzled receptors 2, 3, 4and LRP6 gene mRNA expressed (the relative gray value was 48.50, 34.84, 23.85, 49.73) in the Treg cells by RT-PCR, and Wnt molecular expressed in exosomes-like vesicles. After Treg cells co-cultured with exosomes-like vesicles, the MFI of phosphorylated β-catenin decreased (from 20.06 ± 2.99 to 12.41 ± 2.08), and the expression of Bcl-2 mRNA was upregulated significantly (the relative gray value from 0.45 to 84.97).</p><p><b>CONCLUSIONS</b>Exosomes-like vesicles existed in human plasma and express immune regulatory molecules. They can suppress the proliferation of activated CD4(+) T cells induce their apoptosis and pro-long the survival of natural Treg cells via Wnt signaling pathway.</p>