Effect of mesenchymal stem cell transplantation on immunological injury of the ovary in mice / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effect of mesenchymal stem cell (MSC) transplantation in repairing ovarian injury in mice sensitized with porcine ovarian proteins.</p><p><b>METHODS</b>Wild-type female mice with ICR background (6-8 weeks old) were divided randomly into groups A, B and C (n=12). In groups B and C, the mice were treated with the total protein extract from porcine ovary to induce immunological injury of the ovary, while those in group A received no treatment. MSCs-derived from GFP transgenic mice were transplanted into the mice of group C, and equal volume of PBS was injected intraperitoneally in mice of the other two groups. PCR was used to detect GFP gene in the genomic DNA of the ovaries to assess MSCs homing in the ovary, and the reparative effect of MSCs on ovarian injury was evaluated using HE staining and TUNEL analysis.</p><p><b>RESULTS</b>After transplantation, the MSCs could reach the injured ovaries to promote the repair of the ovarian injury, resulting also in reduced apoptosis of the granulosa cells (GCs) in the injured ovaries.</p><p><b>CONCLUSION</b>MSCs transplantation can promote the recovery of the immunological injury of the ovary in mice, the mechanism of which may involve reduced apoptosis of the GCs.</p>

Secretory expression of recombinant porcine zona pellucida glycoprotein-3alpha (rpZP3alpha) in Pichia pastoris / 生物工程学报

To obtain the recombinant pZP3alpha protein for the study of the contraceptive vaccines, the DNA sequence (446-1423) encoding purified pZP3alpha was inserted into a vector--pPICZalphaA. The recombinant plasmid pPICZalphaA-pZP3alpha was linearized and then transformed into Pichia pastoris GS115 by electroporation. Engineering strains were attained by screening with zeocin and induced to produce rpZP3alpha in high-density fermentation. Then rpZP3alpha was purified by Cu2+ metal affinity column chromatography from the separated and concentrated fermentative supernatants. The purified rpZP3alpha was identified by SDS-PAGE and Western blot, and the quantity, purity and rate of recovery of the rpZP3alpha were analyzed by Quantity One software. One male rabbit was immunized with the Cu-NTA-purified rpZP3alpha. The antibody responses against rpZP3alpha and porcine ZP were detected by ELISA and the indirect immunofluorescence. Engineering strains expressing rpZP3alpha in secretion were constructed. A 46kD component named rpZP3alpha which can react with anti-pZP3 antibody was purified from fermentative supernatants of engineering strains and the average yield of purified rpZP3alpha obtained from fermentative supernatants was 8mg/L. The purity and the rate of recovery were up to 92% and 63% respectively. The anti-rpZP3alpha antiserum was prepared by immunization of a male rabbit with purified rpZP3alpha. This anti-rpZP3alpha antiserum could react with rpZP3alpha and purified pZP3 in ELISA and bind to porcine zona pellucida which produced bright green fluorescence in the indirect immunofluorescence. The rpZP3alpha (46kD) protein could be successfully expressed in the Pichia pastoris expression system. And this protein retained the immunogenic activity of natural pZP3.

Comparison of three methods for evaluating acrosome reaction in human spermatozoa / 中华男科学杂志

<p><b>OBJECTIVE</b>To find a convenient and exact method for evaluating acrosome reaction in human spermatozoa.</p><p><b>METHODS</b>The semen of the normal male was mixed and then divided into 6 groups. Coomassie brilliant blue (CBB) staining, chlortetracycline (CTC) fluorescence staining and acid phosphatase (ACP) detection were used for morphological observation and data analysis of the acrosome status of the human sperm treated with or without progesterone.</p><p><b>RESULTS</b>There were obvious morphological differences between the acrosome-reaction and acrosome-intact spermatozoa in CBB staining and CTC fluorescence staining, and significant differences were observed between the experimental and control spermatozoa by the three methods (P < 0.05).</p><p><b>CONCLUSION</b>All the three methods can be used to assess acrosome reaction in human spermatozoa, but Coomassie brilliant blue (CBB) staining is much more convenient and stable.</p>

Expression of recombinant human zona pellucida-3 protein (rhZP3) in Pichia pastoris / 生物工程学报

Human Zona Pellucida(ZP), which is a complex matrix surrounding oocytes,is comprised of three immunologically distinct glycoproteins(hZP1, hZP2 and hZP3). Because hZP3 possesses the sperm receptor activity and the acrosome-inducing activity, it has long been used as a candidate antigen to develop an immunocontraceptive vaccine. However, a large amount of native hZP3 protein is unavailable. It is an effective way to express hZP3 protein directly in vitro. Nevertheless, it had been reported that the rhZP3 protein produced in Pichia pastoris was not secreted but accumulated in the cells and could only be purified after being solubilized by strong denaturants. More unfortunately, after purification the final product required 6mol/L urea to maintain solubility. An improved project was advanced with the aim to express secreted and soluble rhZP3 protein in yeast. In this study, the fragment of hZP3 cDNA coding for aa 23 - 408, which the N-terminal leader was removed and most of the C-terminal transmembrane-like domain was reserved, was amplified by two PCR primers including EcoR I and Not I sites respectively and a His6 codon cassette was added to 5'-terminal. The hZP3 insert was incorporated into expression vector pPIC9K. The resulting recombinant yeast expression vector was designated pPIC9K-rhZP3. Linearized pPIC9K-rhZP3 was transformed into Pichia pastoris. After G418 selection, the recombinant Pichia pastoris strains were identified by PCR and the rhZP3 was expressed following the manufacturer' s protocol. Following induction with methanol, the rhZP3 protein was secreted and dissolved into the culture supernatant. SDS-PAGE and Western blot analyses showed that the apparent molecular weight of the expressed rhPZ3 proteins in yeast was smaller and a little size heterogeneity than native ones; after purified with Ni-chelating affinity chromatography, the final product's apparent molecular weight was about 32 - 34KD and their yield more than 20mg/L. We supposed that the C-terminal transmembrane-like domain be useful for secretion of rhZP3 into the culture supernatant and the expressed rhZP3 protein be incompletely digested by proteinases of Pichia into shorter fragments which all were glycosylated inhomogeneously. Fortunately, the fragments of rhZP3 protein can be recognized in Western blot by the polyclonal antibodies to porcine ZP3 which has showed a cross-reactivity with human ZP in vitro. It will be expected that the rhZP3 protein expressed in Pichia pastoris not only has immunogencity, say, it can rise antibodies in vivo to prevent spermatozoa-ovum binding, but also does not contain ovarian factors that might be the cause of undesired side effects, e.g. ovaritis and can be used as a safe immunogen in human antifertility vaccine research.