Objective:To prepare heparin (Hep)-modified gelatin methacryloyl (GelMA) microspheres and to investigate their application in liver-targeted delivery of adipose-derived mesenchymal stem cells (ADSCs).Methods:GelMA microspheres were modified with Hep to obtain GelMA-Hep microspheres. The surface morphology of the GelMA-Hep microspheres was observed by scanning electron microscopy. The changes of carbon atoms, nitrogen atoms and sulfur atoms on the surface of the GelMA-Hep microspheres were detected by X-ray photoelectron spectroscopy. The surface chemical group composition of the GelMA-Hep microspheres was analyzed by Fourier transform infrared spectrometer. The swelling properties of the GelMA-Hep microspheres were detected by water absorption swelling experiment. Human liver HL-7702 cells transfected with lentivirus were co-cultured with GelMA, GelMA-dopamine (GelMA-dop) and GelMA-Hep microspheres. The effects of microspheres on cell proliferation activity were evaluated by cell counting kit-8 method and live/dead cell staining experiment. The adhesion of microspheres to cells was observed by confocal microscopy. The GelMA-Hep microspheres loaded with ADSCs were injected into C57BL/6 mice through the tail vein, and its efficiency of liver-targeted delivery of ADSCs was observed by a small animal in vivo imaging system. The data were compared by independent sample t test or one-way analysis of variance. Results:The GelMA-Hep microspheres were prepared by modifying the GelMA microspheres with Hep. Compared with the GelMA microspheres, the size of the GelMA-Hep microspheres did not change significantly, and the surface did not collapse and showed some crystalline particles. The binding energy of sulfur atoms on the surface of the GelMA-Hep microspheres increased from 166 eV to 168 eV. On the surface of the GelMA-Hep microspheres, the characteristic peaks of sulfonic acid and sulfate groups of Hep were detected at 1 490 cm ?1 and from 1 135 cm ?1 to 1 050 cm ?1, respectively. The swelling rate of the GelMA-dop microspheres was uniform, while the swelling rate of the GelMA microspheres and the GelMA-Hep microsphere was quite different, but the final swelling mass of the three microspheres tended to be consistent at 5 min. After 12, 24, 36 and 48 h of culture, the relative proliferation of cells in the GelMA-Hep group (1.61±0.29, 1.78±0.05, 2.27±0.08, 2.26±0.33) were higher than those in the negative control group (1.00±0.00, 1.28±0.06, 1.39±0.02, 1.41±0.04) (all P<0.05). After 36 h of culture, the relative proliferation of cells in the GelMA-Hep group was higher than that in the GelMA-dop group (1.63±0.21), with significant difference ( P<0.05). Live/dead cell staining experiment showed that after 12 h of cell culture in the GelMA-Hep group, only a few microspheres had cell adhesion; at 24 h, the cells were densely distributed on the surface of the microspheres. After 36 h, the number of cells increased further. At 48 h, live cells were distributed throughout the microspheres. Confocal microscopy showed that after 24 h of culture, cells adhered to the surface of the microspheres in the GelMA-Hep group and showed a stretched morphology. The liver of the GelMA-Hep+ADSCs group showed strong fluorescence at 0.5 h, and the fluorescence brightness continued to 48.0 h. The number of ADSCs reaching the liver was more than that of ADSCs group and GelMA+ADSCs group. Conclusions:GelMA-Hep microspheres were successfully prepared, which can improve the efficiency of liver-targeted delivery of ADSCs.

Objective To reveal the mechanisms of immunological infertility,the method of coimmunoprecipitation(CO-IP) and liquid chromatogram mass/mass (LC-MS/MS) was used to screen sperm membrane proteins which interacting with antisperm antibodies (ASA).Methods This study was designed as a case-control.The disease group including 56 serum samples from 521 cryptogenic infertile patients were screened ASA positive by ELISA and conformed with mixed antiglobulin reaction(MAR).The controls were 31 serum samples which ASA is negative and already possessed healthy offspring.All subjects were enrolled from September 2015 to December 2015 in China PLA General Hospital.Spermatozoa samples from 48donors with normal sperm parameters were from January 2016 to April 2016 in China PLA General Hospital.The purified human sperm membrane proteins were then mixed with serum from disease group (positive for ASA) and control group (not containing ASA).The binding proteins of antisperm antibodies were enriched using CO-IP assay.The immunoprecipitates were separated on sodium dodecyl sulfate-polyactylamide gel (SDS-PAGE),then the binding proteins were cut from the gel and analyzed by LC-MS/MS after the enzymolysis.These proteins could bc idcntified as definition,biological function (s) and subccllular localization with Uniprot database.Results The serum samples from infertile persons (39 females and 17males) were screened ASA positive by ELISA and conformed with MAR.The healthy controls (17 females and 14 males) were ASA-negative in ELISA.Forty proteins that interact with ASA were obtained from the study and these could be divided into three groups:11 antigens detected by control serum samples only,14antigens recognised by both infertile patients and control sera,and 15 antigens specific for patients with ASA.These 15 proteins are Sperm Cation channcl protein 1,Sperm Cation channel protein 3,Sperm Cation channel protein 4,Sperm associated antigen 9,Apolipoprotein A-I,Dynein heavy chain 14,Cylicin-2,Izumo sperm-egg fusion protein 4,Thioredoxin domain-containing protein 2,IQ domain-containing protein H,IQ domain-containing protein F1,Spermatogenesis-associated protein 5,Spermatogenesis-associated protein 5-like protein 1,Sperm acrosome membrane-associated protein 1,E3 ubiquitin-protein ligase RNF 114.Conclusion Fifteen proteins discovered with CO-IP technology and LC-MS/MS analysis could be referred as male immunoinfertility-related antigens and they may hold the great importance in revealing the secret of immunological infertility.