[Method for recording tension changes of small pulmonary artery and vein using the isolated vessel tension measurement system]

Objective: To establish a standardized method for isolated pulmonary artery and vein rings with different diameter, pressure and length, which could provide a more scientific method for in vitro study of pulmonary vessel diseases. Methods: Male SD rats were anesthetized, and the right ventricular systolic pressure were measured. Small pulmonary artery and vein rings with 200-400 μm in diameter and 2 mm in length were prepared by dissecting pulmonary arteries and veins. The pulmonary vessel rings were mounted in the organ bath by 2 stainless steel wires with diameter of 40 μm. Then the internal circumference of the vessel rings was increased gradually with 100 μm per step. At the same time the vascular tension was recorded by the Myograph System and Acknowledgement data acquisition system, and subsequently the passive length-tension exponential curve was made. The initial tension of the rings was set, equilibrated for another 30 min, and then stimulated with 60 mmol/L KCl 3 times, and the best contractile reactivity was achieved. The contractile reactivity of pulmonary artery rings and endothelial integrity were detected by exposure to 1 μmol/L phenylephrine(PE) and 10 μmol/L acetylcholine(Ach), while the contractile reactivity of pulmonary vein rings was detected by exposure to 1 μmol/L U46619 and 10 μmol/L papaverine. Results: The contraction and relaxation effects of the pulmonary artery rings reached 0.39 mg and 92% when they were stimulated by 1 μmol/L PE and 10 μmol/L Ach. The contraction and relaxation effects of pulmonary vein rings were up to 0.13 mg and 84% when they were exposed to 1 μmol/L U46619 and 10 μmol/L papaverine, respectively. Conclusion: Pulmonary artery and vein rings with appropriate basal tension and optimal vasodilator activity were prepared, and a standardized method of tension experiment for isolated pulmonary artery and vein rings established.

Human thymic stromal lymphopoietin promotes the proliferation and invasion of cervical cancer cells by downregulating microRNA-132 expression

Thymic stromal lymphopoietin (TSLP), produced by cervical cancer (CC) cells, promotes angiogenesis, and the recruitment and functional regulation of eosinophils. It has been reported that microRNA (miR)-132 is aberrantly decreased in CC tissues. However, the function and mechanism of TSLP on the biological behaviors of CC cells is largely unknown. The aim of the present study was to investigate the effect of TSLP on the expression of miR-132 and the proliferation and invasion in vitro of CC cell lines, namely, HeLa and SiHa cells. The transcrpitional level of miR-132 was analyzed using reverse transcription-quantitative polymerase chaon reaction. The proliferation, invasion, and the expression of proliferation and invasion-related molecules in HeLa and SiHa cells in vitro were evaluated using bromodeoxyuridine cell proliferation, Matrigel invasion assays, flow cytometry and ELISA, respectively. Here, it was revealed that recombinant human TSLP (rhTSLP) downregulated the expression levels of miR-132 in HeLa and SiHa cells, and by contrast, the neutralizing antibodies for TSLP or TSLP receptor (TSLPR) upregulated miR-132 expression levels in HeLa and SiHa cells. The overexpression of miR-132 resulted in a lowered proliferation and invasiveness, decreased levels of proliferation-associated molecules marker of proliferation Ki-67 and proliferating cell nuclear antigen, and the decreased production of matrix metalloproteinase (MMP)2 and MMP9 in HeLa and SiHa cells. Compared with the control group, there was a higher level of proliferation and invasion in HeLa and SiHa cells following stimulation with rhTSLP. However, these effects induced by rhTSLP were significantly impaired in HeLa and SiHa cells with miR-132 overexpression. The results of the present study indicated that TSLP produced by CC cells downregulated miR-132 expression, and stimulated the proliferation and invasion of CC cells, thereby further promoting the development of CC.

Cisplatin inhibits the growth, migration and invasion of cervical cancer cells by down-regulating IL-17E/IL-17RB

Interleukin (IL)-17E mainly produced by immune cells, is a distinct member of the IL-17 cytokine family, which has multifarious immunomodulatory activities. As a potent anticancer drug, cisplatin is commonly used against various types of solid tumors. The present study was performed to investigate whether cisplatin regulates the expression of IL-17E and it receptor IL-17RB, and the role of IL17E in cervical cancer cells in vitro. The expression of IL-17E and IL-17RB in cervical cancer cells was detected by flow cytometry and ELISA. The viability, apoptosis, migration and invasion of cervical cancer cells were analyzed by CCK8, Annexin V-7AAD apoptosis, transwell migration, wound healing, and matrigel invasion assays. Here, we found that cervical cancer cells co-expressed IL-17E and IL-17RB, especially HeLa and SiHa cells. Recombinant human IL-17E protein (rhIL-17E) enhanced the viability, migration and invasion of HeLa and SiHa cells, and blocking IL-17E with anti-human IL-17RE neutralizing antibody promoted the apoptosis of HeLa and SiHa cells. Cisplatin significantly down-regulated the expression of IL-17E and IL-17RB, and further reversed the regulatory effects of rhIL-17E on viability, apoptosis, migration and invasion of HeLa and SiHa cells. The results suggest that cisplatin inhibits the viability, migration, invasion, and promotes the apoptosis of cervical cancer cells possibly by down-regulating IL-17E/17RB signaling. Cisplatin may be the first choice for cervical cancer patients with abnormally high IL-17E expression.

[Optimization of alkaline hydrolysis based on the side chain of diethyl ester 4-amino-N5-formyl-N8, N10-dideazatetrahydrofolic acid]

OBJECTIVE

To optimize and establish the best hydrolysis method of diethyl ester 4-amino-N⁵-formyl-N⁸, N¹⁰-dideazatetrahydrofolate through the optimization of simple compound of diethyl N-(4-aminobenzoyl)-L-glutamate.

METHODS

To increase the low yield of hydrolysis reaction of diethyl ester 4-amino-N⁵-formyl-N⁸, N¹⁰-dideazatetrahydrofolate due to the by-products and difficult purification, we studied the effect of NaOH and KOH, two kinds of alkalis, three concentrations between 0.175-1 mol/L and five types of reaction time involved in 20, 30, 60, 120 and 180 min on the common side chain diethyl N-(4-aminobenzoyl)-L-glutamate. A high performance liquid chromatography was established for measuring the target product and the by-products in reaction liquid in different reaction conditions. Finally, on the basis of the best hydrolysis method of diethyl ester 4-amino-N⁵-formyl-N⁸, N¹⁰-dideazatetrahydrofolate, we completed the optimization of the hydrolysis reaction conditions of diethyl ester 4-amino-N⁵-formyl-N⁸, N¹⁰-dideazatetrahydrofolate.

RESULTS

We developed the best reaction condition for the hydrolysis of diethyl ester 4-amino-N⁵-formyl-N⁸, N¹⁰-dideazatetrahydrofolate, which could be carried out easily and efficiently. The results indicated that treated with the optimized condition of 0.3 mol/L KOH in 60 min at the room temperature, diethyl ester 4-amino-N⁵-formyl-N⁸, N¹⁰-dideazatetrahydrofolate was converted into its diacid derivative in 95.6 % yield, which turned to be a better reaction condition compared with the previous reaction condition. The structures of those compounds were identified to be correct by 1H nuclear magnetic resonance(1H NMR), 13C nuclear magnetic resonance(13C NMR) and electrospray ionization time of flight mass spectrometry (ESI-MS). The purity of the diacid derivative of the compound was determined to be 96% by high performance liquid chromatography(HPLC).The new hydrolysis reaction condition could not only avoid the formation of single ester hydrolysis product and amide bond hydrolysis product, but also improve the yield of the hydrolysis reaction.

CONCLUSION

We have developed an efficient reaction for the hydrolysis of diethyl ester 4-amino-N⁵-formyl-N⁸, N¹⁰-dideazatetrahydro. Since the final step of the synthesis of classical folic acid antagonists is always the catalyzed hydrolysis of the side chain glutamate, the reaction also has great significance for anti-folic acid anti-tumor inhibitors synthesis.

Chemokine CCL17 induced by hypoxia promotes the proliferation of cervical cancer cell

Cervical cancer is often associated with hypoxia and many kinds of chemokines. But the relationship and role of hypoxia and Chemokine (C-C motif) ligand 17 (CCL17) in cervical cancer are still unknown. Here, we found that CCL17 was high expressed in cervical cancer. HeLa and SiHa cells could secrete CCL17 in a time-dependent manner. Hypoxia increased expression of CCL17 receptor (CCR4) on HeLa and SiHa cells. Treatment with recombination human CCL17 (rhCCL17) led to an elevation of cell proliferation in HeLa and SiHa cells in a dose-dependent manner. In contrast, blocking CCL17 with anti-human CCL17 neutralizing antibody (α-CCL17) played an oppose effect. However, rhCCL17 had no effect on apoptosis in cervical cancer cells. Further analysis showed that hypoxia promoted the proliferation of HeLa and SiHa cells, and these effects could be reversed by α-CCL17. Stimulation with the inhibitor for c-Jun N-terminal kinase (JNK) or signal transducers and activator of transcription 5 (STAT5) signal pathway not only directly decreased the proliferation of HeLa and SiHa cells, but also abrogated the stimulatory effect of rhCCL17 on the proliferation of HeLa and SiHa cells. These results suggest that a high level of CCL17 in cervical cancer lesions is an important regulator in the proliferation of cervical cancer cells through JNK and STAT5 signaling pathways. In this process, hypoxia magnifies this effect by up-regulating CCR4 expression and strengthening the interaction of CCL17/CCR4.

Chemokine CCL24 promotes the growth and invasiveness of trophoblasts through ERK1/2 and PI3K signaling pathways in human early pregnancy

Chemokine CCL24, acting through receptor CCR3, is a potent chemoattractant for eosinophil in allergic diseases and parasitic infections. We recently reported that CCL24 and CCR3 are co-expressed by trophoblasts in human early pregnant uterus. Here we prove with evidence that steroid hormones estradiol (E), progesterone (P), and human chorionic gonadotropin (hCG), as well as decidual stromal cells (DSCs) could regulate the expression of CCL24 and CCR3 of trophoblasts. We further investigate how trophoblast-derived CCL24 mediates the function of trophoblasts in vitro, and conclude that CCL24/CCR3 promotes the proliferation, viability and invasiveness of trophoblasts. In addition, analysis of the downstream signaling pathways of CCL24/CCR3 show that extracellular signal-regulated kinases (ERK1/2) and phosphoinositide 3-kinase (PI3K) pathways may contribute to the proliferation, viability and invasiveness of trophoblasts by activating intracellular molecules Ki67 and matrix metallopeptidase 9 (MMP9). However, we did not observe any inhibitory effect on trophoblasts when blocking c-Jun N-terminal kinase (JNK) or p38 pathways. In conclusion, our data suggests that trophoblast-derived CCL24 at the maternal-fetal interface promotes trophoblasts cell growth and invasiveness by ERK1/2 and PI3K pathways. Meanwhile, pregnancy-related hormones (P and hCG), as well as DSCs could up-regulate CCL24/CCR3 expression in trophoblasts, which may indirectly influence the biological functions of trophoblasts. Thus, our results provide a possible explanation for the growth and invasion of trophoblasts in human embryo implantation.

Combination of CD4(+)CD25(+)CD127(-) regulatory T cells with MLC-BE and BE-Ab2: an efficient evaluation of the therapy of paternal lymphocyte induced immunization in unexplained recurrent spontaneous abortion patients

The aim of this retrospective study was to compare the immune tolerance status of patients suffered from unexplained spontaneous abortion (URSA) before and after treatment with paternal lymphocyte induced immunization (PLII) four times, and its relationship to the pregnancy outcome. 168 URSA patients were included in the present study. Among 168 couples, 138 couples were conceived again, of whom 86 were successfully pregnant till 20 gestational weeks, 31 cases again failed in the first trimester, 21 cases were still under follow-up, another 30 cases still had not conceived. Both the level of one way mixed lymphocyte culture blocking efficiency (MLC-BE) and anti-idio blocking antibody (BE-Ab2) were markedly elevated in succeeded group after PLII. In contrast, although a significant increase could be observed in the failed group after treatment, the elevation of BE-Ab2 was much lower than that in successful group. PLII therapy significantly up-regulated the percentage of peripheral CD4(+)CD25(+)CD127(-) regulatory T cells (Tregs) in successfully pregnant women; however, there was no significant change of Tregs in pregnancy loss cases although receiving PLII therapy. These results suggested a positive correlation between higher frequency of Tregs and rate of successful pregnancies. The sensitivity and specificity of combination of Tregs with MLC-BE and BE-Ab2 were 81.8% and 81.3%, respectively. Therefore, the percentage of Tregs in peripheral blood may hopefully serve as a potential biomarker for monitoring the efficacy of therapy in URSA patients. Combination of Tregs with MLC-BE and BE-Ab2 may expect to better evaluate the efficacy of PLII in URSA patients.

Molecular adjuvant C3d3 improved the anti-hCGbeta humoral immune response in vaginal inoculation with live recombinant Lactobacillus expressing hCGbeta-C3d3 fusion protein

To enhance the contraceptive efficiency of human chorionic gonadotrophin (hCG)-beta contraceptive vaccine, we coupled hCG-beta gene with molecular adjuvant C3d3, and cloned into live Lactobacilli (Lb.) to express fusion protein hCGbeta-C3d3. The recombinant Lb. could survive in BALB/c murine vagina for at least 3 weeks. After inoculating BALB/c and C57BL/6 mice via vagina, we found that the antibody titer peaks induced by the Lb.hCGbeta-C3d3 inoculation were higher significantly than the Lb.hCGbeta. T and B cells in spleen and vagina were significantly increased, and anti-hCGbeta IgG and IgA antibody-secreting cells in uterus and vagina were significantly increased compared to the control in different strain mice. Our study shows that the C3d3 can display apparent adjuvant efficiency to induce more powerful humoral response to the hCGbeta antigen in vaginal mucosal immunization.

Mucosal inoculation of Lactobacillus expressing hCGβ induces an anti-hCGβ antibody response in mice of different strains

To show that an anti-human chorionic gonadotrophin-beta (hCGbeta) antibody response can be induced by inoculating Lb. expressing hCGbeta through different mucosal pathways in mice of two strains, female BALB/c and C57BL/6 mice were immunized via vaginal, oral or nasal routes with 10(8), 10(9), and 10(10)Lb.hCGbeta (a recombinant Lactobacillus expressing hCGbeta). The mice were immunized twice with a booster in study week 3. An indirect ELISA was used to determine anti-hCGbeta IgG and IgA antibodies in vaginal lavage and serum, obtained from the 2nd to 8th week after the primary immunization. Flow cytometry was used to analyze the lymphocyte proliferation from these tissues, 1 week after the primary immunization. The hCGbeta antigen-specific antibody-secreting cells of spleen, uterus, and vagina were evaluated by enzyme-linked immunospot assay (ELISpot), 2 weeks after the booster. The analysis showed that 10(9) and 10(10)Lb.hCGbeta inoculations induced similar anti-hCGbeta antibody responses, while the three mucosal pathways induced similar antibody responses. The antiserum obtained after boosters with 10(9) and 10(10)Lb. hCGbeta was able to neutralize more than 100 ng/ml hCG antigen, both in BALB/c and C57BL/6 mice. The highest antibody titer induced by vaginal mucosal immunization was stronger than that obtained via the other mucosal pathways. The B cells in the vagina appeared to proliferate after vaginal immunization (P<0.05). The numbers of anti-hCGbeta IgG and IgA antibody-secreting cells in the uterus and vagina were greater than in the spleen. Therefore, the vaginal mucosal route appears to be a better immunization pathway to induce higher anti-hCGbeta antibody levels in the reproductive tract.

Gene conjugation of molecular adjuvant C3d3 to hCGβ increased the anti-hCGβ Th2 and humoral immune response in DNA immunization

Human chorionic gonadotropin (hCG) has been used as an anti-fertility vaccine and as a target for cancer immunotherapy. We have explored the use of three copies of C3d in DNA vaccine as molecular adjuvant to improve the immunogenicity of this hormone in previous work and found that the immune response induced by pcDNA3-hCGbeta-C3d3 has been enhanced 243-fold compared with pcDNA3-hCGbeta following DNA immunization in BALB/c mice. In the present study, a new functionally active DNA vaccine of hCGbeta-C3d3 chimera based on pCMV4 vector has been described. We compared the expression efficiency of pCMV4 and pcDNA3 eukaryotic vectors for hCGbeta and hCGbeta-C3d3 fusion protein and the immune response of mice immunized with pcDNA3-hCGbeta, pCMV4-hCGbeta, pcDNA3-hCGbeta-C3d3 and pCMV4-hCGbeta-C3d3, respectively, at 25, 50 and 100 pmol dose, and further analyzed the levels of Th1 and Th2 cytokines produced by spleen lymphocytes of the immunized mice upon hCG restimulation in vitro. It was found that pCMV4 vector achieved 1.3-1.5-fold higher protein expression and raised 1.1-1.2 (primary) and 1.2-1.3 (booster) logs higher titer of anti-hCGbeta IgG than pcDNA3. Mice vaccinated with 50 pmol of hCGbeta-C3d3-DNAs elicited the highest titer of hCGbeta-specific antibody among the serial doses and the immune response induced by pCMV4-hCGbeta-C3d3 were, respectively, 1.3, 1.3 and 1.2 logs higher than that of pcDNA3-hCGbeta-C3d3 and 2.2, 2.9 and 2.4 logs higher than that of pCMV4-hCGbeta at week 2 following the booster immunization. Moreover, we observed that the production of IL-4 and IL-10 increased in mice vaccinated with hCGbeta-C3d3-DNAs and the ratio of IL-4/IFN-(gamma) showed a Th2 bias of immune response in the mice immunized with hCGbeta-C3d3-DNAs. These findings indicated that gene fusion of C3d3 to hCGbeta, as a means of harnessing the adjuvant potential of the innate immune system, may improve the antigen-specific Th2 humoral immune response of the hCGbeta DNA vaccine and the pCMV4 vector is a more ideal eukaryotic vector for DNA vaccine than pcDNA3.

Enhancement of humoral immunity to the hCG beta protein antigen by fusing a molecular adjuvant C3d3

The vaccine directed against human chorionic gonadotropin (hCG) has previously undergone clinical test demonstrating the feasibility of the approach in preventing pregnancy in women. Some individuals, however, did not response adequately despite employing highly immunogenic bacterial toxoids as carriers. In this study, we investigated the potential of three copies of C3d as a new molecular adjuvant to enhance the immunogenicity of hCG beta protein antigen. The antibody response to the hCG beta-C3d3 fusion protein immunization was compared with those resulting from immunization with the hCG beta alone and the hCG beta plus CFA/IFA either in BALB/c mice or in C(57)BL/6J mice. Our results showed that the fusion of C3d3 to hCG beta protein antigen resulted in a significant elevation of the serum anti-hCG beta antibody level in the two mouse strains and the antibodies were capable of effectively neutralizing the bioactivity of hCG. The immunization with C3d3 as a molecular adjuvant favored Th2 bias of immune response. The immunity-enhancing effect of the C3d3 was 10-fold (initial) and 20-32-fold (booster) greater than CFA/IFA. These findings indicated that fusion of C3d3 to hCG beta, as a means of harnessing the adjuvant potential of the innate immune system, may improve immunogenicity of the hCG beta contraceptive vaccine, which is useful to produce a cost-effective vaccine and for the less-responsive population.

Inoculation of Lactobacillus expressing hCG beta in the vagina induces an anti-hCG beta antibody response in murine vaginal mucosa

OBJECTIVES

To test the possibility of vaccination with lactobacillus expressing hCG beta antigen administered by vaginal mucosal immunization.

METHODS

A plasmid pIlac-hCG beta was constructed and then transfected into Lactobacillus casei CECT5276, which stably expressed hCG beta protein. RIA was used to detect hCG beta in the culture supernatant and cell lysate. Western blotting was performed to evaluate the expressed protein of interest. Female BALB/c mice aged 6-8 weeks received inoculations in the vagina of the recombinant L. casei CECT5276. ELISA was used to determine the anti-hCG beta IgA antibody in vaginal lavage fluid from the BALB/c mice after vaginal mucosal immunization.

RESULTS

The pIlac alone appeared to have a higher efficiency than pIlac-hCG beta, and the highest transfection efficiency of both plasmids was at pulse voltages of 1200 V and 1500 V. About 78.5% of the hCG beta protein was excreted into the culture supernatant. Excretion of hCG beta was most efficient when the pH of the culture medium was adjusted to around 7.0 and the concentration of lactose was around 1%. The hCG beta protein in the vaginal lavage fluid of these BALB/c mice was positive on the third day after vaginal inoculation. Anti-hCG beta IgA antibody continued to be found in the vaginal lavage fluid for 2 weeks following a booster vaginal inoculation. The splenic lymphocytes of the mice immunized with hCG beta through the vagina underwent a proliferative reaction to hCG antigen restimulation in vitro. Interferon gamma (IFN-gamma) and interleukin (IL)-4 were secreted at higher levels after vaginal mucosal immunization of L. casei expressing hCG beta than after vaginal mucosal immunization of L. casei alone.

CONCLUSIONS

Vaginal immunization of lactobacillus expressing hCG beta induced an anti-hCG beta antibody response in the murine vaginal mucosa. Induction of the antigen-specific antibodies in the reproductive tract following vaginal inoculation of recombinant lactobacillus will lead to the development of a safe, efficient, and easy-to-use form of immunocontraception.

Human first-trimester trophoblast cells recruit CD56brightCD16- NK cells into decidua by way of expressing and secreting of CXCL12/stromal cell-derived factor 1

More than 70% of decidual lymphocytes are NK cells characterized by CD56(bright)CD16(-) phenotype, but the mechanisms by which these NK cells are recruited in the decidua are still almost unrevealed. In this study, we first analyzed the transcription of 18 chemokine receptors in the first-trimester decidual CD56(bright)CD16(-) NK cells. Among these receptors, CXCR4 and CXCR3 were found highly transcribed, and the expression of CXCR4 was verified in most of the decidual CD56(bright)CD16(-) NK cells by flow cytometry. The first-trimester human trophoblasts were found expressing CXCL12/stromal cell-derived factor 1, the specific ligand of CXCR4, by way of in situ hybridization and immunohistochemistry. The primary cultured trophoblast cells were also found to secrete stromal cell-derived factor 1alpha spontaneously, and its concentration was 384.6 +/- 90.7 pg/ml after the trophoblast cells had been cultured for 60 h. All of the ligands for CXCR3 were below the minimal detectable concentration when trophoblast cells were cultured for up to 48 h. Both recombinant human SDF-1alpha and supernatants of the cultured trophoblast cells exhibited chemotactic activity on decidual CD56(bright)CD16(-) NK cells. Our findings suggest that human first-trimester trophoblast cells produce CXCL12, which in turn chemoattracts decidual CD56(bright)CD16(-) NK cells. This activity could contribute to the recruitment mechanism of decidual lymphocytes, especially CD56(bright)CD16(-) NK cells, in decidua, and may be used at a local level to modulate the immune milieu at the materno-fetal interface.

Blockade of CD86 signaling facilitates a Th2 bias at the maternal-fetal interface and expands peripheral CD4+CD25+ regulatory T cells to rescue abortion-prone fetuses

Intervention in B7 (CD80/CD86)/B7-ligand (CD28/CTLA-4) pathways is an effective way of preventing unwanted immune responses, such as allograft rejection. Pregnancy maintenance represents maternal tolerance to the fetal allograft, which is accompanied by a type 2 helper cell (Th2) bias at the maternal-fetal interface. Here, the costimulatory signal of CD86 was selectively blocked, and that of CD80 was kept unimpaired by administration of anti-murine CD86 monoclonal antibody at the early gestational stage in abortion-prone CBA/JxDBA/2 matings and normal pregnant CBA/JxBALB/c matings. It was demonstrated that in vivo blockade of CD86 costimulation could suppress maternal immune attack to the fetus by shifting cytokines from Th1 predominance to Th2 bias at the maternal-fetal interface, and expanding peripheral CD4+CD25+ regulatory T cells, which play an important role in the development and maintenance of maternal-fetal tolerance. Furthermore, the expression of CD28 and its ligands CD80/CD86 on peripheral lymphocytes was down-regulated, whereas that of CTLA-4 was up-regulated, which might facilitate the suppressive effect of CD4+CD25+ regulatory T cells on the alloreactive T cells. The maternal-fetal immunotolerance induced by CD86 blockade decreased fetal resorption in CBA/JxDBA/2 matings, but did not affect normal pregnant CBA/JxBALB/c matings. These results suggest that selective blockade of CD86 costimulation leads to maternal immune tolerance to embryo antigen, and might contribute to a rational immunoregulatory regimen for recurrent spontaneous abortion.

Adoptive Transfer of Paternal Antigen-Hyporesponsive T Cells Induces Maternal Tolerance to the Allogeneic Fetus in Abortion-Prone Matings

The embryo expresses paternal Ags foreign to the mother and therefore has been viewed as an allograft. It has been shown that anergic T cells generated by blocking of the CD28/B7 costimulatory pathway with anti B7-1 and anti B7-2 mAbs can be transferred as suppresser cells to prevent allograft rejection. Little is known, however, about the in vivo function of anti-B7-treated T cells after their transfer into abortion-prone mice in the maintenance of materno-fetal tolerance. In the present study, abortion-prone CBA/J females mated with DBA/2 males were administered anti-B7-1 and anti-B7-2 mAbs on day 4 of gestation (murine implantation window). The anti-B7-treated T cells subsequently were adoptively transferred into abortion-prone CBA/J mice. We demonstrated that costimulation blockade with anti-B7 mAbs at the time of implantation resulted in altered allogeneic T cell response and overcame increased maternal rejection to the fetus in the CBA/JxDBA/2 system. The transferred anti-B7-treated T cells appeared to be regulatory, decreasing responsiveness and generating clonal deviation in maternal recipient T cells. The transferred CFSE-labeled T cells were found to reside in the spleen and uterine draining lymph nodes, and a few were localized to the materno-fetal interface of the maternal recipient. Our findings suggest that the anti-B7-treated T cells not only function as potent suppresser cells, but also exert an immunoregulatory effect on the maternal recipient T cells, which cosuppresses maternal rejection to the fetus. This procedure might be considered potentially useful for fetal survival when used as an immunotherapy for human recurrent spontaneous abortion.

The Expression of CXCR4/CXCL12 in First-Trimester Human Trophoblast Cells1

Chemokines and chemokine receptors have been implicated as pivotal players in many physiological and pathological situations, but little is known about the expression and function of chemokines and chemokine receptors at the materno-fetal interface. In this study, we first analyzed the transcription of 18 chemokine receptors in first-trimester human trophoblast cells. Among these receptors, CXCR4 was found highly transcribed. We demonstrated afterward that both CXCR4 and CXCL12 (stromal cell-derived factor-1; SDF-1) were expressed in trophoblast cells. Primary cultured trophoblast cells were also found secreting CXCL12 spontaneously. To identify the functional role of CXCR4/CXCL12 in these cells, we treated trophoblast cells with recombinant human (rh)SDF-1 alpha and analyzed the cell viability and signaling pathway. The results showed that rhSDF-1 alpha increased the viability of trophoblast cells and the activation of extracellular signal-regulated kinases signaling pathway in vitro. Our findings suggest that first-trimester trophoblast cells express functional CXCR4/CXCL12, which may play an important role in early pregnancy such as stimulating trophoblast cell proliferation or differentiation in an autocrine manner.

Gene fusion of molecular adjuvant C3d to hCGβ enhances the anti-hCGβ antibody response in DNA immunization

OBJECTIVE

To express the hCGbeta-C3d3 fusion protein in a CHO cell continual expression system to investigate further the adjuvant effects of C3d on contraceptive vaccination.

METHOD

We constructed a plasmid pcDNA3-hCGbeta-C3d3 which contains three copies of murine C3d cDNA and the hCGbeta gene by cloning the chimerical hCGbeta-C3d3 cDNA into the eukaryotic vector pcDNA3 downstream of the CMV promoter. The plasmid was transfected into a COS-7 cell transient expression system and a CHO cell continual expression system. RIA was used to detect hCGbeta in the culture supernatant. Western blot and Raji cell immunohistochemical assays were performed to evaluate the expressed protein. Then, 6-8-week-old female BALB/c mice were inoculated intramuscularly with pcDNA3-hCGbeta and pcDNA3-hCGbeta-C3d3, and ELISA was used to assess anti-hCGbeta IgG antibody in serum.

RESULTS

In 72 h after COS-7 cells were transfected with the plasmid pcDNA3-hCGbeta-C3d3, 1.0x10(5) cells could secrete 152 ng of the recombinant protein (calculated by hCGbeta contained). The transfected CHO cells, which were then screened by G418, could continuously secrete the fusion protein at 660 ng/10(6) cells/48 h. The hCGbeta-C3d3 protein was purified by anti-hCGbeta immunoaffinity chromatography. Raji cell immunohistochemical assay demonstrated that both the hCGbeta and C3d3 were successfully fused. After DNA immunization intramuscularly, the anti-hCGbeta IgG antibody titer in the pcDNA3-hCGbeta-C3d3 immunized group was 243-fold higher than that of the pcDNA3-hCGbeta immunized group.

CONCLUSION

We have expressed the hCGbeta-C3d3 protein successfully, both in a transient expression system (COS-7 cells) and in a stable expression system (CHO cells). The C3d3 molecular adjuvant can enhance significantly the immunogenecity of hCGbeta antigen in DNA immunization.

Studies on treatment of acute promyelocytic leukemia with arsenic trioxide: remission induction, follow-up, and molecular monitoring in 11 newly diagnosed and 47 relapsed acute promyelocytic leukemia patients

Fifty-eight acute promyelocytic leukemia (APL) patients (11 newly diagnosed and 47 relapsed) were studied for arsenic trioxide (As2O3) treatment. Clinical complete remission (CR) was obtained in 8 of 11 (72.7%) newly diagnosed cases. However, As2O3 treatment resulted in hepatic toxicity in 7 cases including 2 deaths, in contrast to the mild liver dysfunction in one third of the relapsed patients. Forty of forty-seven (85.1%) relapsed patients achieved CR. Two of three nonresponders showed clonal evolution at relapse, with disappearance of t(15;17) and PML-RARalpha fusion gene in 1 and shift to a dominant AML-1-ETO population in another, suggesting a correlation between PML-RARalpha expression and therapeutic response. In a follow-up of 33 relapsed cases over 7 to 48 months, the estimated disease-free survival (DFS) rates for 1 and 2 years were 63.6% and 41.6%, respectively, and the actual median DFS was 17 months. Patients with white blood cell (WBC) count below 10 x 10(9)/L at relapse had better survival than those with WBC count over 10 x 10(9)/L (P =.038). The duration of As2O3-induced CR was related to postremission therapy, because there was only 2 of 11 relapses in patients treated with As2O3 combined with chemotherapy, compared with 12 of 18 relapses with As2O3 alone (P =.01). Reverse transcription polymerase chain reaction (RT-PCR) analysis in both newly diagnosed and relapsed groups showed long-term use of As2O3 could lead to a molecular remission in some patients. We thus recommend that ATRA be used as first choice for remission induction in newly diagnosed APL cases, whereas As2O3 can be either used as a rescue for relapsed cases or included into multidrug consolidation/maintenance clinical trials.