iPSC-derived mesenchymal stem cells attenuate cerebral ischemia-reperfusion injury by inhibiting inflammatory signaling and oxidative stress

Induced pluripotent stem cell-derived mesenchymal stem cells (iMSCs) hold great promise as a cell source for transplantation into injured tissues to alleviate inflammation. However, the therapeutic efficacy of iMSC transplantation for ischemic stroke remains unknown. In this study, we evaluated the therapeutic effects of iMSC transplantation on brain injury after ischemia-reperfusion using a rat transient middle cerebral artery occlusion model and compared its therapeutic efficacy with that of bone marrow mesenchymal stem cells (BMMSCs). We showed that iMSCs and BMMSCs reduced infarct volumes after reperfusion and significantly improved motor function on days 3, 7, 14, 28, and 56 and cognitive function on days 28 and 56 after reperfusion compared with the vehicle group. Furthermore, immunological analyses revealed that transplantation of iMSCs and BMMSCs inhibited microglial activation and expression of proinflammatory cytokines and suppressed oxidative stress and neuronal cell death in the cerebral cortex at the ischemic border zone. No difference in therapeutic effect was observed between the iMSC and BMMSC groups. Taken together, our results demonstrate that iMSC therapy can be a practical alternative as a cell source for attenuation of brain injury and improvement of neurological function because of the unlimited supply of uniform therapeutic cells.

Association between glomerular filtration rate and plasma N-terminal pro-atrial natriuretic peptide concentration in dogs

OBJECTIVES

To investigate the association between plasma N-terminal pro-atrial natriuretic peptide concentration and glomerular filtration rate in dogs.

MATERIALS AND METHODS

Dogs were classified into four categories by bodyweight. Dogs were divided into four groups (Groups 1 to 4) based on glomerular filtration rate estimates using plasma iohexol clearance per bodyweight category. Generalised linear models were built to explore the relationship between plasma N-terminal pro-atrial natriuretic peptide concentration and glomerular filtration rate and the effect of confounders on plasma N-terminal pro-atrial natriuretic peptide concentration.

RESULTS

Fifty-three dogs were included (Group 1, 25; Group 2, seven; Group 3, five; and Group 4, 16). The medians (interquartile range) N-terminal pro-atrial natriuretic peptide concentrations for Groups 1 to 4 were 7224 pg/mL (4766 to 10,254 mg/dL), 8958 pg/mL (4935 to 11,271 mg/dL), 9280 pg/mL (9195 to 10,384 mg/dL) and 12,683 pg/mL (9133 to 19,217 mg/dL), respectively. Group 4, estimated to have the highest reduction in glomerular filtration rate, had a higher plasma N-terminal pro-atrial natriuretic peptide concentration than Groups 1 to 3. Based on the final generalised linear model, influencing factors for plasma N-terminal pro-atrial natriuretic peptide concentration were plasma iohexol clearance (-0.136; 95% confidence interval, -0.227 to -0.046) and bodyweight (-0.058; 95% confidence interval, -0.098 to -0.018).

CLINICAL SIGNIFICANCE

N-terminal pro-atrial natriuretic peptide concentration is associated with the glomerular filtration rate.

Neat1 lncRNA organizes the inflammatory gene expressions in the dorsal root ganglion in neuropathic pain caused by nerve injury

Primary sensory neurons regulate inflammatory processes in innervated regions through neuro-immune communication. However, how their immune-modulating functions are regulated in concert remains largely unknown. Here, we show that Neat1 long non-coding RNA (lncRNA) organizes the proinflammatory gene expressions in the dorsal root ganglion (DRG) in chronic intractable neuropathic pain in rats. Neat1 was abundantly expressed in the DRG and was upregulated after peripheral nerve injury. Neat1 overexpression in primary sensory neurons caused mechanical and thermal hypersensitivity, whereas its knockdown alleviated neuropathic pain. Bioinformatics analysis of comprehensive transcriptome changes indicated the inflammatory response was the most relevant function of genes upregulated through Neat1. Consistent with this, upregulation of proinflammatory genes in the DRG following nerve injury was suppressed by Neat1 knockdown. Expression changes of these proinflammatory genes were regulated through Neat1-mRNA interaction-dependent and -independent mechanisms. Notably, Neat1 increased proinflammatory genes by stabilizing its interacting mRNAs in neuropathic pain. Finally, Neat1 in primary sensory neurons contributed to spinal inflammatory processes that mediated peripheral neuropathic pain. These findings demonstrate that Neat1 lncRNA is a key regulator of neuro-immune communication in neuropathic pain.

Characterization of Megabat-Favored, CA-Dependent Susceptibility to Retrovirus Infection

The isolation of the Koala retrovirus-like virus from Australian megabats and the identification of endogenous retroviruses in the bat genome have raised questions on bat susceptibility to retroviruses in general. To answer this, we studied the susceptibility of 12 cell lines from 11 bat species to four well-studied retroviruses (human and simian immunodeficiency viruses [HIV and SIV] and murine leukemia viruses [B- and N-MLV]). Systematic comparison of retroviral susceptibility among bats revealed that megabat cell lines were overall less susceptible to the four retroviruses than microbat cell lines, particularly to HIV-1 infection, whereas lineage-specific differences were observed for MLV susceptibility. Quantitative PCR of reverse transcription (RT) products, infection in heterokaryon cells, and point mutation analysis of the capsid (CA) revealed that (i) HIV-1 and MLV replication were blocked at the nuclear transport of the pre-integration complexes and before and/or during RT, respectively, and (ii) the observed lineage-specific restriction can be attributed to a dominant cellular factor constrained by specific positions in CA. Investigation of bat homologs of the three previously reported post-entry restriction factors constrained by the same residues in CA, tripartite motif-protein 5α (TRIM5α), myxovirus resistance 2/B (Mx2/MxB), and carboxy terminus-truncated cleavage and polyadenylation factor 6 (CPSF6-358), demonstrated poor anti-HIV-1 activity in megabat cells, whereas megabat TRIM5α restricted MLV infection, suggesting that the major known CA-dependent restriction factors were not dominant in the observed lineage-specific susceptibility to HIV-1 in bat cells. Therefore, HIV-1 susceptibility of megabat cells may be determined in a manner distinct from that of primate cells. IMPORTANCE Recent studies have demonstrated the circulation of gammaretroviruses among megabats in Australia and the bats' resistance to HIV-1 infection; however, the origins of these viruses in megabats and the contribution of bats to retrovirus spread to other mammalian species remains unclear. To determine the intrinsic susceptibility of bat cells to HIV-1 infection, we investigated 12 cell lines isolated from 11 bat species. We report that lineage-specific retrovirus restriction in the bat cell lines can be attributed to CA-dependent factors. However, in the megabat cell lines examined, factors known to bind capsid and block infection in primate cell culture, including homologs of TRIM5α, Mx2/MxB, and CPSF6, failed to exhibit significant anti-HIV-1 activities. These results suggested that the HIV-1 susceptibility of megabat cells occurs in a manner distinct from that of primate cells, where cellular factors, other than major known CA-dependent restriction factors, with lineage-specific functions could recognize retroviral proteins in megabats.

Evaluation of parameters for efficient purification and long-term storage of herpes simplex virus-based vectors

Replication competent oncolytic herpes simplex virus (HSV) vectors have been used extensively to treat solid tumors with promising results. However, highly defective HSV vectors will be needed for applications that require sustained therapeutic gene expression in the absence of vector-related toxicity or inflammation. These vectors require complementing cell lines for their manufacture, creating significant challenges to achieve high yields of infectious virus particles. We recently described an improved upstream process for the production of a non-cytotoxic HSV vector for gene therapy applications. Here, we sought to optimize the downstream conditions for purification and long-term storage of the same vector, JΔNI5. We compared different methods to remove cellular impurities and concentrate the vector by monitoring both physical and biological titers, resulting in the establishment of optimal conditions for vector production. To optimize the long-term storage parameters for non-cytotoxic HSV vectors, we evaluated vector stability at low temperature and sensitivity to freeze-thaw cycles. We report that suboptimal purification and storage methods resulted in loss of vector viability. Our results describe effective and reproducible protocols for purification and storage of HSV vectors for pre-clinical studies.

A PCR-amplified transgene fragment flanked by a single copy of a truncated inverted terminal repeat for recombinant adeno-associated virus production prevents unnecessary plasmid DNA packaging

The application of recombinant adeno-associated viruses (rAAVs) for gene therapy faces certain challenges, including genome packaging of non-vector sequences. Inverted terminal repeats (ITRs) flanking the rAAV genome, comprising three inverted repeat regions (A, B, and C) and a non-inverted repeat region (D), contribute to non-vector genome packaging. We aimed to circumvent this issue by comparing the properties of rAAV containing DNA plasmids and PCR-amplified transgenes, including a single copy of the AD sequence (rAAV-pAD/L-AD, respectively), which is a truncated form of ITR, with those of wild-type ITR genome (single-stranded and self-complementary AAV; ssAAV and scAAV). The packaging efficiency of rAAV-pAD/L-AD was found to be comparable to that of scAAV, whereas the transduction efficiency of rAAV-pAD/L-AD was lower than that of ss/scAAV. Remarkably, rAAV-L-AD reduced the plasmid backbone packaging contamination compared to ss/scAAV. Furthermore, to confirm the functionality of this system, we generated a rAAV-L-AD harboring a short hairpin RNA targeting ATP5B (rAAV-L-AD-shATP5B) and found that it caused a significant decrease in ATP5B mRNA levels when transduced into HEK293EB cells, suggesting that it was functional. Thus, our system successfully packaged L-AD into capsids with minimal contamination of plasmid DNA, offering a novel functional packaging platform without causing plasmid backbone encapsidation.

Fibroblast growth factor-23 as an early marker of CKD-mineral bone disorder in dogs: preliminary investigation

OBJECTIVES

To examine the relationship between fibroblast growth factor-23 levels, chronic kidney disease severity and mineral metabolic disorders associated to chronic kidney disease in dogs.

MATERIALS AND METHODS

Fifteen control and 75 chronic kidney disease dogs were retrospectively included. Serum fibroblast growth factor-23 concentration and other phosphate metabolite parameters were compared between controls and each International Renal Interest Society stage. Multiple regression analysis was performed to determine the predictors of fibroblast growth factor-23.

RESULTS

Serum fibroblast growth factor-23 concentrations were significantly higher in dogs with IRIS stages 2, 3 and 4 chronic kidney disease than those in dogs in control group and with stage 1 and increased along with the severity of chronic kidney disease. Compared with control dogs, serum intact parathyroid hormone significantly increased from stage 2 and serum phosphorus concentrations increased in dogs with stage 4. In dogs with stage 2, fibroblast growth factor-23 levels significantly increased in those with hyperphosphatemia compared with those with normophosphatemia. While eight of 26 (30.8%) dogs with stage 2 developed hyperparathyroidism (intact parathyroid hormone>8.5 ng/L), 19 (73.1%) dogs with stage 2 had elevated fibroblast growth factor-23 levels above the reference range (>528 pg/mL). Log creatinine, log intact parathyroid hormone and log product of total calcium and phosphorus were independent predictors of log fibroblast growth factor-23.

CLINICAL SIGNIFICANCE

This preliminary study suggests that canine fibroblast growth factor-23 might be involved in mineral metabolic disorders associated to chronic kidney disease in dogs, and this factor could be potentially used as an early marker for this condition.

Use of vertebral left atrial size for staging of dogs with myxomatous valve disease

INTRODUCTION/OBJECTIVES

The American College of Veterinary Internal Medicine (ACVIM) guidelines suggest that pimobendan should be initiated in dogs which meet all criteria of stage B2 myxomatous mitral valve disease (MMVD): murmur intensity ≥ 3/6, left atrial-to-aortic ratio ≥ 1.6, normalized left ventricular internal diameter in diastole ≥ 1.7, and vertebral heart size > 10.5. Recently, a new radiographic index for left atrial enlargement, vertebral left atrial size (VLAS), was proposed. The objective of the present study was to evaluate whether VLAS is useful in staging MMVD and if it can distinguish between ACVIM stages B1 and B2.

ANIMALS

Ninety-seven client-owned dogs with MMVD were evaluated and classified as ACVIM stage B1, B2, or C-D.

MATERIALS AND METHODS

The echocardiographs and radiographs of all the dogs were retrospectively evaluated to obtain left atrial-to-aortic ratio, normalized left ventricular internal diameter in diastole, and VLAS values. The data were analyzed to assess the correlation between these measurements and VLAS, and the optimal cutoff value of VLAS was determined.

RESULTS

A VLAS cutoff value of 2.6 provided the greatest diagnostic accuracy for identification of dogs with ACVIM stage B2 MMVD (area under the curve, 0.96; sensitivity, 95%; specificity, 84%). A VLAS ≥2.5 exhibited the highest sensitivity (sensitivity, 100%; specificity, 78%), and a VLAS ≥ 3.1 exhibited the highest specificity (sensitivity, 47%; specificity, 100%).

CONCLUSIONS

VLAS is a helpful index for monitoring MMVD using radiography. A VLAS cutoff value of 2.5 could be used to identify dogs that may benefit from echocardiography to determine if they have reached ACVIM stage B2.

Protocol Optimization for the Production of the Non-Cytotoxic JΔNI5 HSV Vector Deficient in Expression of Immediately Early Genes

Non-toxic herpes simplex virus (HSV) vectors can be generated by functional deletion of all immediate-early (IE) genes, providing a benign vehicle with potential for gene therapy. However, deletion of multiple IE genes raises manufacturing concerns and thus limits clinical application of these vectors. To address this issue, we previously developed a novel production cell line, called U2OS-ICP4/27, by lentiviral transduction of human osteosarcoma U2OS cells with two essential HSV IE genes, ICP4 and ICP27. To optimize the process of vector manufacturing on this platform, we evaluated several cell culture parameters of U2OS-ICP4/27 for high-titer and -quality production of non-toxic HSV vectors, revealing that the yields and functionality of these vectors can be significantly influenced by culturing conditions. We also found that several chemical compounds can enhance the replication of non-toxic HSV vectors and their release from producer cells into the supernatants. Notably, the vector produced by our optimized protocol displayed a greatly improved vector yield and quality and showed elevated transgene expression in cultures of primary dorsal root ganglion neurons. Taken together, our optimized production approach emerges as a relevant protocol for high-yield and high-quality preparation of non-toxic HSV-based gene therapy vectors.

Dorsal Root Ganglia Homeobox downregulation in primary sensory neurons contributes to neuropathic pain in rats

Transcriptional changes in primary sensory neurons are involved in initiation and maintenance of neuropathic pain. However, the transcription factors in primary sensory neurons responsible for neuropathic pain are not fully understood. Dorsal Root Ganglia Homeobox (DRGX) is a paired-like homeodomain transcription factor necessary for the development of nociceptive primary sensory neurons during the early postnatal period. However, roles for DRGX after development are largely unknown. Here, we report that DRGX downregulation in primary sensory neurons as a result of post-developmental nerve injury contributes to neuropathic pain in rats. DRGX expression was decreased in nuclei of small and medium primary sensory neurons after spinal nerve ligation. DRGX downregulation by transduction of a short hairpin RNA with an adeno-associated viral vector induced mechanical allodynia and thermal hyperalgesia. In contrast, DRGX overexpression in primary sensory neurons suppressed neuropathic pain. DRGX regulated matrix metalloproteinase-9 (MMP-9) and prostaglandin E receptor 2 mRNA expression in the DRG. MMP-9 inhibitor attenuated DRGX downregulation-induced pain. These results suggest that DRGX downregulation after development contributes to neuropathic pain through transcriptional modulation of pain-related genes in primary sensory neurons.

A statistical model for activation of Factor C by binding to LPS aggregates

Published data on Factor C activity at various LPS and Lipid A concentrations (Nakamura et al. in Eur J Biochem 176:89, 1988; Kobayashi et al. in J Biol Chem 37:25987, 2014) were rearranged to show that Factor C exhibited its maximum activity at a specific concentration of LPS. A statistical model was proposed for examining whether a single LPS molecule binding activates Factor C (monomeric activation) or dimerization of Factor C is necessary for the activation (dimeric activation). In the monomeric activation model the plots of the relative activity of Factor C against the molar ratio of LPS to Factor C were different from those in the published data. The plots in the dimeric activation model lie on a bell-shaped curve, whatever the Factor C concentration, matching the published data and indicating the appropriateness of that model. We suggest that Factor C is activated by multiple molecular interactions of Factor C with LPS aggregates on which it dimerises and that this explains why larger aggregates are less effective at activating Factor C than smaller ones.

Crystallization kinetics of safflower and olive oils during low-temperature storage

The crystallization behaviors of safflower and olive oils were investigated according to changes in volume and transmitted light intensity during isothermal storage at low temperature. The changes between the oils were significantly different even though their fatty acid compositions were similar, with oleic acid accounting for more than 75% (w/w) of the total oil. It was expected that minor components with high melting points would affect the crystallization behaviors of these oils. The crystallization processes of the oils were then analyzed using a kinetic model in which the oil crystallizes through two different processes. It is suggested that although the crystallization behaviors were apparently different, the crystallization mechanisms of these oils are essentially the same.

Abstract P3-10-19: Significance of baseline neutrophil-to-lymphocyte ratio for progression-free survival of patients with HER2-positive locally advanced and metastatic breast cancer treated with trastuzumab emtansine

Purpose The prognosis of human epidermal growth factor receptor 2 (HER2)-positive locally advanced or metastatic breast cancers (MBCs) has dramatically improved due to the introduction of trastuzumab, pertuzumab, and trastuzumab emtansine (T-DM1). The efficacy of T-DM1 is prolonged for some patients; however, the predictive factors remain unknown. There is a report that T-DM1 induced antitumor immunity in patients treated with neoadjuvant therapy, with tumor infiltrating lymphocytes (TILs) increasing after the administration of T-DM1. Based on these observations, the benefits of T-DM1 for prognosis may be mediated by an immune reaction against breast cancers, at least in part. As an indicator of cancer immunity, in addition to TILs, the neutrophil-to-lymphocyte ratio (NLR) has been established in early breast cancers. In the present study, we investigated the usefulness of the NLR for treatment efficacy of T-DM1 in HER2-positive MBCs. Methods Fifty-three advanced or metastatic breast cancers treated with T-DM1 were retrospectively recruited from three institutes. The NLR in the peripheral blood was measured at baseline (just before the start of T-DM1) and after one cycle (just before the start of cycle 2). The cutoff value of the NLR was set at 2.56 (median value) and progression-free survival (PFS) and overall survival (OS) according to NLR levels were evaluated. Results The PFS of patients with NLR-low at baseline (NLR<2.56; n=26; median, not reached) was significantly better than that of patients with NLR-high (NLR≥2.56; n=27; median, 4.13 months; hazard ratio [HR], 0.226; 95% confidence interval [CI], 0.112-0.493; p=0.0001). There was a significant association between improved OS and a low NLR (HR, 0.384; 95% CI, 0.170-0.910; p=0.0296). In the subgroup analysis, patients with NLR-low consistently had improved PFS compared to those with NLR-high irrespective of the number of prior chemotherapy regimens, prior trastuzumab use, visceral metastasis, estrogen receptor status, and HER2 immunohistochemical staining score. According to univariable analysis of each clinical and biological factor for PFS, the NLR-low group was solely and significantly associated with favorable PFS compared with the NLR-high group (HR, 0.226; 95% CI, 0.112-0.493; p=0.0001). The NLR at baseline was significantly decreased (p=0.0010) and lymphocyte count was significantly increased after one cycle treatment (p=0.0005). Interestingly, the PFS of patients whose NLR was high at baseline but changed to low after one cycle (n=12; median PFS, 6.47 months) was better than that of patients with a consistently high NLR (n=14; median PFS, 3.27 months). Conclusion and Discussion A low baseline NLR was found to be significantly associated with improved PFS for patients treated with T-DM1. Interestingly, lymphocyte count was significantly increased in patients in the NLR-low group but not in the NLR-high group after one cycle treatment. Although detailed mechanisms remain unknown, the treatment efficacy of T-DM1 may be partly mediated by immunoreaction on the basis of present data. A low baseline NLR appears to be beneficial for treatment with T-DM1 in HER2-positive breast cancers.

Citation Format: Imamura M, Morimoto T, Egawa C, Miyagawa Y, Miyoshi Y. Significance of baseline neutrophil-to-lymphocyte ratio for progression-free survival of patients with HER2-positive locally advanced and metastatic breast cancer treated with trastuzumab emtansine [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P3-10-19.

Epstein–Barr virus-associated hemophagocytic syndrome in a patient with ulcerative colitis during treatment with azathioprine: A case report and review of literature

A 19-year-old female was diagnosed with ulcerative colitis when she presented with persistent melena, and has been treated with 5-aminosalicylic acid for 4 years, with additional azathioprine for 2 years at our hospital. The patient experienced high-grade fevers, chills, and cough five d prior to presenting to the outpatient unit. At first, the patient was suspected to have developed neutropenic fever; however, she was diagnosed with Epstein-Barr virus-associated hemophagocytic syndrome (EB-VAHS) upon fulfilling the diagnostic criteria after bone marrow aspiration. When patients with inflammatory bowel disease treated with immunomodulators, such as thiopurine preparations, develop fever, EB-VAHS should be considered in the differential diagnosis.

Highly Efficient Ultracentrifugation-free Chromatographic Purification of Recombinant AAV Serotype 9

Recombinant adeno-associated virus serotype 9 (rAAV9) can specifically transduce muscle and neuronal tissues; thus, rAAV9 can potentially be used in gene therapy. However, rAAV9 is the most challenging rAAV serotype to purify. Traditionally, rAAV9 has been purified by ultracentrifugation, which is not scalable. We recently described a chromatographic purification protocol for rAAV1; this protocol can achieve scalable purifications. In this study, we attempted to optimize this protocol for purifying rAAV9 preparations, and we developed a novel, effective method for high-yield purification of rAAV9 using quaternary ammonium anion exchangers and size-exclusion chromatography. The final purified rAAV9 contained mainly three capsid proteins, as observed by SDS-PAGE. Furthermore, negative-stain electron microscopy demonstrated that 96.1% ± 1.1% of rAAV9 particles carried the viral genome containing the EGFP transgene, indicating that impurities and empty capsids can be eliminated with our purification protocol. The final rAAV9 titer obtained by our protocol totaled 2.5 ± 0.4 × 10¹⁵ viral genomes produced from ∼3.2 × 10⁹ HEK293EB cells. We confirmed that our protocol can also be applied to purify other varied AAV genome constructs. Our protocol can scale up production of pure rAAV9, in compliance with current good manufacturing practice, for clinical applications in human gene therapy.

Evaluation of the inhibitory effects of telmisartan on drug-induced renin-angiotensin-aldosterone system activation in normal dogs

INTRODUCTION

This study examined whether the angiotensin II receptor blocker telmisartan had inhibitory effects on drug-induced renin-angiotensin-aldosterone system (RAAS) activation in normal dogs.

ANIMALS

Five healthy laboratory beagles were used in this study.

METHODS

Each dog received amlodipine (0.5 mg/kg, q12h, PO) alone for 14 days. Starting on the next day, animals received both amlodipine and telmisartan (1.0 mg/kg, q24h, PO) for 84 days. Systolic blood pressure, heart rate, plasma biochemical variables (blood urea nitrogen, creatinine, and electrolytes), plasma renin activity, and 24-h urinary aldosterone elimination (U-Aldo) were measured before amlodipine administration; at day 0; and at days 1, 7, 14, 28, 56, and 84 of telmisartan treatment.

RESULTS

Telmisartan was associated with significant decreases in systolic blood pressure on day 56 (p=0.046), whereas heart rate did not significantly change during this treatment (p=0.061). Plasma renin activity was significantly increased on days 1, 7, 28, 56, and 84 during telmisartan administration (all p=0.04). No change in median U-Aldo was detected following telmisartan administration (p=0.241). When U-Aldo was evaluated in individual animals, two dogs displayed evidence of aldosterone breakthrough.

CONCLUSIONS

Telmisartan administration did not suppress RAAS activation. The appearance of aldosterone breakthrough supports the incomplete blockade of RAAS activation.

Systematic characterization of human testis-specific actin capping protein β3 as a possible biomarker for male infertility

STUDY QUESTION

Is actin capping protein (CP) β3 involved in human spermatogenesis and male infertility?

SUMMARY ANSWER

Human CPβ3 (hCPβ3) is expressed in testis, changes its localization dynamically during spermatogenesis, and has some association with male infertility.

WHAT IS KNOWN ALREADY

The testis-specific α subunit of CP (CPα3) was previously identified in human, and mutations in the cpα3 gene in mouse were shown to induce malformation of the sperm head and male infertility. However, CPβ3, which is considered to be a heterodimeric counterpart of CPα3, has been neither characterized in human nor reported in association with male infertility.

STUDY DESIGN, SIZE, DURATION

To confirm the existence of CPβ3 in human testis, fresh semen samples from proven fertile men were analyzed. To investigate protein expression during spermatogenesis, cryopreserved testis obtained from men with obstructive azoospermia were examined by immunofluorescent analysis. To assess the association of CP with male infertility, we compared protein expression of human CPα3 (hCPα3) and hCPβ3 using immunofluorescent analysis of cryopreserved sperm between men with normozoospermia (volunteers: Normo group, n = 20) and infertile men with oligozoospermia and/or asthenozoospermia (O + A group, n = 21).

PARTICIPANTS/MATERIALS, SETTING, METHODS

The tissue-specific expression of hCPβ3 was investigated by RT-PCR and Western blot analysis. To investigate whether hCPα3 and hCPβ3 form a heterodimer, a tandem expression vector containing hcpα3 tagged with monomeric red fluorescent protein 1 and hcpβ3 tagged with enhanced green fluorescent protein in a single plasmid was constructed and analyzed by co-immunoprecipitation (Co-IP) assay. The protein expression profiles of hCPα3 and hCPβ3 during spermatogenesis were examined by immunohistochemical analysis using human spermatogenic cells. The protein expressions of hCPα3 and hCPβ3 in sperm were compared between the Normo and O + A groups by immunohistochemical analysis.

MAIN RESULTS AND THE ROLE OF CHANCE

RT-PCR showed that mRNA of hcpβ3 was expressed exclusively in testis. Western blot analysis detected hCPβ3 with anti-bovine CPβ3 antibody. Co-IP assay with recombinant protein showed that hCPα3 and hCPβ3 form a protein complex. At each step during spermatogenesis, the cellular localization of hCPβ3 changed dynamically. In spermatogonia, hCPβ3 showed a slight signal in cytoplasm. hCPβ3 expression was conspicuous mainly from spermatocytes, and hCPβ3 localization dynamically migrated from cytoplasm to the acrosomal cap and acrosome. In mature spermatozoa, hCPβ3 accumulated in the postacrosomal region and less so at the midpiece of the tail. Double-staining analysis revealed that hCPα3 localization was identical to hCPβ3 at every step in the spermatogenic cells. Most spermatozoa from the Normo group were stained homogenously by both hCPα3 and hCPβ3. In contrast, significantly more spermatozoa in the O + A versus Normo group showed heterogeneous or lack of staining for either hCPα3 or hCPβ3 (abnormal staining) (P < 0.001). The percentage of abnormal staining was higher in the O + A group (52.4 ± 3.0%) than in the Normo group (31.2 ± 2.5%). Even by confining the observations to morphologically normal spermatozoa selected in accordance with David's criteria, the percentage of abnormal staining was still higher in the O + A group (39.9 ± 2.9%) versus the Normo group (22.5 ± 2.1%) (P < 0.001). hCPβ3 in conjunction with hCPα3 seemed to play an important role in spermatogenesis and may be associated with male infertility.

LARGE SCALE DATA

Not applicable.

LIMITATIONS REASONS FOR CAUTION

Owing to the difficulty of collecting fresh samples of human testis, we used cryopreserved samples from testicular sperm extraction. To examine the interaction of spermatogenic cells or localization in seminiferous tubules, fresh testis sample of healthy males are ideal.

WIDER IMPLICATIONS OF THE FINDINGS

The altered expression of hCPα3 and hCPβ3 may not only be a cause of male infertility but also a prognostic factor for the results of ART. They may be useful biomarkers to determine the fertilization ability of human sperm in ART.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported by a Grant-in-Aid for Young Scientists (B) from the Japan Society for the Promotion of Science (JP16K20133). The authors declare no competing interests.

Abstract P2-09-31: Predictive impact of absolute lymphocyte counts for progression-free survival in HER2-positive advanced breast cancer treated with pertuzumab and trastuzumab plus eribulin or nab-paclitaxel

Background: Tumor-infiltrating lymphocytes might be a one of predictive outcome of human epidermal growth factor receptor 2 (HER2)-positive advanced breast cancer (ABC) patients (pts) who treated with trastuzumab and pertuzumab (TP) plus docetaxel. Although peripheral blood-based parameter (PBBP) is reported as a prognostic indicator of patients with early breast cancers, utility of PBBP has not been studied in HER2-positive ABC.

Objective:The aim of our study was to determine whether PBBP is significant for predictive efficacy in HER2-positive ABC treated with TP combined with eribulin (ERI) or nab-paclitaxel (Nab-PTX).

Methods: The 51 patients' data from two single arm phase II trials was included in this retrospective-prospective study; ERI + TP (n=30) or Nab-PTX + TP (n=21) registered with UMIN000012375 or UMIN000006838, respectively. We assessed the PBBP in prospectively collected data and investigated their association with progression-free survival (PFS). In consideration of PBBP, we evaluated absolute lymphocyte count (ALC), neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR). The cutoff values of ALC, NLR, and PLR were set at 1000 cells/μL, 2, and 250, respectively.

Results:Median age at baseline was 58 years (range: 31-77). Median number of previous chemotherapy was 3 (range: 1-10). Pts had multiple metastases, 53% with LNs, 35% with bone, 25% with lung, 20% with liver, and 6% with brain. The objective response rate (CR+PR) and clinical benefit rate (CR+PR+ more than 6 month SD) were 37% (n=19) and 59% (n=30), respectively. The median PFS of all pts was 301 days (range: 21-1281). The PFS of pts with ALC-High was significantly better than those of ALC-low (hazard ratio (HR): 2.74, 95% confidence interval (CI): 1.28 to 5.86; p= .0097). Furthermore, improved PFS was obtained in pts with ALC greater than 1500 cells/μL compared with less than 1000 cells/uL (HR: 4.05, 95% CI: 1.60 to 11.6; p= .0029). Significant associations seem to exist irrespective of number of previous chemotherapy. Since we combined different studies for evaluating PBBP, ERI and Nab-PTX were calculated separately. Marginally significant associations between ALC and PFS were obtained both in ERI (HR: 2.18, 95% CI: 0.87 to 5.60; p=.0973) and Nab-PTX (HR: 3.26, 95% CI: 0.80 to 12.4; p=.0939). The PFS of NLR-low pts was significantly better than those of NLR-high (HR: 2.29, 95% CI: 1.01 to 5.90; p= .0477), but this statistical difference was inferior to those of ALC. There was no significant association between PLR and PFS.

Conclusions: Pre-treatment ALC-High was significantly correlated with favorable PFS of pts treated with TP irrespective of combination chemotherapy in HER2-positve ABC. Prolonged PFS of TP combination therapy might be obtained mediating through host systemic onco-immunity. These data obtained here suggest that a usefulness of ALC for selecting pts who might have clinical benefit from TP combination therapy for heavily treated HER2-positve ABC.

Citation Format: Araki K, Ito Y, Fukada I, Kobayashi K, Ohno S, Miyagawa Y, Imamura M, Kira A, Takatsuka Y, Egawa C, Suwa H, Miyoshi Y. Predictive impact of absolute lymphocyte counts for progression-free survival in HER2-positive advanced breast cancer treated with pertuzumab and trastuzumab plus eribulin or nab-paclitaxel [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P2-09-31.

Deletion of the Virion Host Shut-off Gene Enhances Neuronal-Selective Transgene Expression from an HSV Vector Lacking Functional IE Genes

The ability of herpes simplex virus (HSV) to establish lifelong latency in neurons suggests that HSV-derived vectors hold promise for gene delivery to the nervous system. However, vector toxicity and transgene silencing have created significant barriers to vector applications to the brain. Recently, we described a vector defective for all immediate-early gene expression and deleted for the joint region between the two unique genome segments that proved capable of extended transgene expression in non-neuronal cells. Sustained expression required the proximity of boundary elements from the latency locus. As confirmed here, we have also found that a transgene cassette introduced into the ICP4 locus is highly active in neurons but silent in primary fibroblasts. Remarkably, we observed that removal of the virion host shutoff (vhs) gene further improved transgene expression in neurons without inducing expression of viral genes. In rat hippocampus, the vhs-deleted vector showed robust transgene expression exclusively in neurons for at least 1 month without evidence of toxicity or inflammation. This HSV vector design holds promise for gene delivery to the brain, including durable expression of large or complex transgene cassettes.

Phase I/II clinical trial to assess safety and efficacy of intratumoral and subcutaneous injection of HVJ-E in castration-resistant prostate cancer patients

Inactivated Sendai virus particles (hemagglutinating virus of Japan envelope (HVJ-E)) have a novel antitumor effect: HVJ-E fused to prostate cancer cells via cell surface receptor causes apoptosis of prostate cancer cells in vitro and in vivo. HVJ-E also induces antitumor immunity by activating natural killer (NK) cells and cytotoxic T cells and suppressing regulatory T cells in vivo. We conducted an open-label, single-arm, phase I/II clinical trial in patients with castration-resistant prostate cancer (CRPC) to determine the safety and efficacy of intratumoral and subcutaneous injection of HVJ-E. Patients with CRPC who were docetaxel-resistant or could not receive docetaxel treatment were eligible. HVJ-E was injected directly into the prostate on day 1 and subcutaneously on days 5, 8 and 12 in two 28-day treatment cycles using a 3+3 dose-escalation design. The primary end points were to evaluate safety and tolerability of HVJ-E. The secondary end points were to analyze tumor immunity and antitumor effect. The study is registered at UMIN Clinical Trials Registry, number UMIN000006142. Seven patients were enrolled, and six patients received HVJ-E. Grade 2 or 3 adverse events (Common Terminology Criteria for Adverse Events Ver. 4.0) were urinary retention and lymphopenia from which the patients recovered spontaneously. No Grade 4 adverse events were observed. Radiographically, three patients had stable disease in the low-dose group, and one patient had stable disease and two had progressive disease in the high-dose group. The prostate-specific antigen (PSA) declined from 14 to 1.9 ng ml^-1 in one patient in the low-dose group after two cycles of HVJ-E treatment, and the PSA response rate was 16.6%. NK cell activity was elevated from day 12 to day 28 after HVJ-E administration, whereas serum interleukin-6, interferon (IFN)-α, IFN-β and IFN-γ levels were not affected by HVJ-E treatment. Intratumoral and subcutaneous injections of HVJ-E are feasible and PSA response was observed in a subgroup of CRPC patients.

Abstract P2-05-27: Baseline serum CA15-3 levels are associated with prognosis for breast cancer patients with non-complete pathological response to neoadjuvant chemotherapy

Background: It has been well demonstrated that patients who achieved pathological complete response (pCR) after neoadjuvant chemotherapy (NAC) had a favorable prognosis compared with patients who did not (non-pCR). Even though pCR was not attained, reduction in tumor volume after chemotherapy may be associated with improved prognosis for a certain number of patients. However, the association between residual tumor volume and prognosis is not necessarily consistent. In order to identify substitute markers for breast cancer patients with non-pCR after NAC, we investigated the impact of serum levels of carcinoembryonic antigen (CEA) and carbohydrate antigen (CA15-3) at baseline as well as post-NAC.

Patients and Methods: Ninety-six breast cancer patients treated with NAC and operated on at the Hyogo College of Medicine were recruited for this study. Serum CEA and CA15-3 were measured prior to chemotherapy as well as at completion of pre-operative treatment. The optimal cutoff points for CEA (1.55ng/m, normal range: &lt;5.0ng/ml) and CA15-3 (13.25U/ml, normal range: &lt;28.0U/ml) for relapse-free survival (RFS) were determined by analyzing the area under receiver operating characteristic curves in another study involving 613 breast cancer patients. Expression levels of Ki67 in samples obtained at pre- and post-NAC were also determined by means of immunohistochemical staining. Pathological complete response was classified as the absence of residual invasive cancer in the breast and lymph nodes. During a 2.13 years median follow-up period, 15 patients suffered relapse.

Results: pCR and non-pCR was attained by 21 and 75 patients, respectively. For the non-pCR patients, serum CEA levels at baseline were classified into high (n=35) and low (n=38) and serum CA15-3 levels at baseline into high (n=31) and low (n=43). RFS of non-pCR patients with high serum CA15-3 levels was significantly worse than of those with low levels (3-year RFS: 0.47 vs 0.93; p=0.0009). RFS for patients with high and low serum levels of CA15-3 after NAC was also significantly different (p=0.037). As for CEA, no significant association with RFS was observed either at baseline or post-NAC. Univariate analysis demonstrated that tumor size and baseline CA15-3 were significant prognostic factors for RFS. Multivariate analysis showed that both tumor size (hazard ratio (HR): 3.88, 95% confidence interval (CI): 1.21-12.35, p=0.023) and baseline CA15-3 (HR: 13.51, 95% CI: 1.74-105.08, p=0.013) were significant and independent risk factors for relapse. As for lymph node metastasis, tumor grade, residual tumor size and pre- and post-NAC Ki67 expression levels of patients with non-pCR showed no significant association with RFS.

Conclusion and discussion: High levels of serum CA15-3 at baseline constituted a significantly worse prognosis for breast cancer patients with non-pCR. Tumor size at baseline but not residual size and baseline CA15-3 seems to suitable as a substitute for prediction of outcome for patients with non-pCR. Our findings suggest that these markers may be useful for identifying patients with poor prognosis who may be candidates for additional adjuvant treatment.

Citation Format: Fujimoto Y, Imamura M, Higuchi T, Nishimukai A, Yanai A, Miyagawa Y, Murase K, Takatsuka Y, Miyoshi Y. Baseline serum CA15-3 levels are associated with prognosis for breast cancer patients with non-complete pathological response to neoadjuvant chemotherapy [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P2-05-27.

Wnt signaling regulates hepatobiliary repair following cholestatic liver injury in mice

Hepatic repair is directed chiefly by the proliferation of resident mature epithelial cells. Furthermore, if predominant injury is to cholangiocytes, the hepatocytes can transdifferentiate to cholangiocytes to assist in the repair and vice versa, as shown by various fate-tracing studies. However, the molecular bases of reprogramming remain elusive. Using two models of biliary injury where repair occurs through cholangiocyte proliferation and hepatocyte transdifferentiation to cholangiocytes, we identify an important role of Wnt signaling. First we identify up-regulation of specific Wnt proteins in the cholangiocytes. Next, using conditional knockouts of Wntless and Wnt coreceptors low-density lipoprotein-related protein 5/6, transgenic mice expressing stable β-catenin, and in vitro studies, we show a role of Wnt signaling through β-catenin in hepatocyte to biliary transdifferentiation. Last, we show that specific Wnts regulate cholangiocyte proliferation, but in a β-catenin-independent manner.

CONCLUSION

Wnt signaling regulates hepatobiliary repair after cholestatic injury in both β-catenin-dependent and -independent manners. (Hepatology 2016;64:1652-1666).

Abstract P2-08-24: High levels of serum C-terminal crosslinking telopeptide of type 1 collagen at baseline are associated with poor prognosis for breast cancer patients

Background: It has been demonstrated that adjuvant treatment using bisphosphonate may reduce recurrence among breast cancer patients. However, these improved prognoses of patients are reportedly limited to breast cancers of estrogen receptor (ER)-positive and postmenopausal women. Although the mechanisms of the effects of bisphosphonate remain unknown, this finding seems to represent support for the hypothesis that suppression of bone resorption by bisphosphonate results in favorable prognoses at least for patients in this subset. In order to determine the prognostic significance of bone resorption in breast cancer patients, we investigated these markers c-terminal crosslinking telopeptide of type I collagen (1CTP) and N-telopeptide of type I collagen (NTX).

Patients and Methods: 469 breast cancer patients were recruited who were operated on Hyogo College of Medicine and histologically confirmed to have invasive carcinoma. Serum 1CTP and NTX were measured preoperatively with the two-antibody radioimmunoassay and enzyme-linked immunosorbent assay methods, respectively, and blood samples were obtained before treatment from patients who were treated with neoadjuvant chemotherapy or endocrine therapy. The area under receiver operating characteristic curves were applied and optimal cutoff values were set at 3.6ng/ml for 1CTP, and 10.55nmolBCE/L premenopausal and 14.05nmolBCE/L postmenopausal for NTX. The relationships between these bone turnover markers and various clinicopathological characteristics were evaluated with the chi square or Fisher's exact test. The log-rank test was used to compare relapse-free survival (RFS) in Kaplan-Meier plots. Associations of RFS were assessed with a Cox proportional-hazards model based on the results of univariate and multivariate analyses. Differences were considered statistically significant if p&lt;0.05.

Results: There were significantly more 1CTP-high patients among postmenopausal women and RFS of 1CTP-high patients was significantly worse than that of 1CTP-low patients (5-year RFS: 0.65 vs 0.86; p=0.0002). Similarly, NTX-high patients were significantly associated with postmenopausal status, but there was no significant association between NTX-high worse RFS (p=0.0976). Multivariate analysis of tumor size, lymph node metastasis and nuclear grade identified 1CTP (hazard ratio: 2.04, 95% confidence interval: 1.13-3.68; p=0.018) as a significant independent prognostic factor. Subset analyses of 1CTP showed that prognosis was consistently worse recognized for postmenopausal (p=0.0002), but not premenopausal (p=0.37) patients. Furthermore, prognosis for 1CTP-high patients was worse for the estrogen receptor (ER)-positive subset (p=0.0005) but not for the ER-negative subset (p=0.22).

Conclusion and discussion: High levels of serum bone resorption markers at baseline were identified as significant unfavorable prognostic factors for breast cancer patients. The prognostic significance of 1CTP seems to be prominent for postmenopausal patients with ER-positive breast cancers. These findings suggest the use of bone-modifying agents as an adjuvant therapy may be beneficial for breast cancer patients, especially for patients with high serum levels of 1CTP.

Citation Format: Imamura M, Nishimikai A, Yanai A, Miyagawa Y, Higuchi T, Ozawa H, Murase K, Takatsuka Y, Miyoshi Y. High levels of serum C-terminal crosslinking telopeptide of type 1 collagen at baseline are associated with poor prognosis for breast cancer patients. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P2-08-24.

Abstract P6-16-01: Differences in patterns of change of bone turnover markers during treatment with bone-modifying agents of breast cancer patients with bone metastases

Background: Bone-modifying agents have demonstrated their efficacy for treatment by suppressing osteoclast function. The activity of bone-modifying agents can be monitored by means of bone resorption markers such as c-terminal crosslinking telopeptide of type I collagen (1CTP) and N-telopeptide of type I collagen (NTX) as well as bone forming marker bone-specific alkaline phosphatase (BAP). In contrast to these markers which indirectly indicate bone turnover, tartrate-resistant acid phosphatase-5b (Tracp-5b) has been established as a direct marker showing osteoclast number and activity. The aim of this study was to identify the relative significance of these bone turnover markers as indicators of treatment efficacy induced by bone-modifying agents for breast cancer patients with bone metastases.

Patients and Methods: For this study, 52 breast cancer patients with bone metastases treated with bone-modifying agents were recruited. Zoledronic acid and denosumab were administered as bone-modifying agents to 36 and 22 patients, respectively (for 6 patients, denosumab was used after zoledronic acid). Serum Tracp-5b, 1CTP, NTX and BAP were measured with, respectively, the EIA (enzyme immunoassay), RIA (two-antibody radioimmunoassay), ELISA (enzyme-linked immunosorbent assay) and CLEIA (chemiluminescent enzyme immunoassay) method. Blood samples were obtained pretreatment and 1, 3 and 6 months after treatment. Changes in these bone turnover markers were statistically analyzed with Friedman's test, and correlation between serum markers and clinicopathological factors was calculated with Mann-Whitney's test.

Results: Serum tracp-5b decreased significantly after treatment (p&lt;0.0001). The baseline median value of Tracp-5b (457.5mU/dl, range: 173-1630mU/dl) had been reduced to 137mU/dl (91-795mU/dl) 1 month after treatment, but no further reduction was observed after that. For 13 out of 15 patients to whom Tracp-5b was administered, abnormally high levels (above 420mU/dl) decreased to normal range with one month treatment. Serum NTX was also significantly reduced after treatment (p=0.0007). The median baseline value (16.5nmolBCE/L, 6.1-52.2nmolBCE/L) was diminished after 1 month (to 10.9nmolBCE/L, 7.0-49.5nmolBCE/L), and further reduction of NTX was observed after 3 months (9.55nmolBCE/L, 6.4-56.0nmolBCE/L). Similarly, baseline BAP (15.1μg/L, 6.4-81.3μg/L) decreased significantly (p=0.0032), a reduction which was obtained after 3 months (10.15μg/L, 6.1-51.7μg/L), but not after 1 month (13.0μg/L, 7.7-137.0μg/L). On the other hand, reduction in 1CTP was not significant (p=0.83).

Conclusion and discussion: Although baseline values of the bone turnover markers Tracp-5b, NTX and BAP decreased significantly after treatment with bone-modifying agents, the pattern of reduction for these three markers varied. Tracp-5b appears to reflect efficacy of bone-modifying agents most quickly and sensitively, possibly due to its direct link to the number and activity of osteoclasts. These findings may prove usefulness of Tracp-5b when considering the efficacy of various bone-modifying agents in clinical practice.

Citation Format: Higuchi T, Nishimukai A, Yanai A, Miyagawa Y, Murase K, Imamura M, Ozawa H, Takatsuka Y, Miyoshi Y. Differences in patterns of change of bone turnover markers during treatment with bone-modifying agents of breast cancer patients with bone metastases. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P6-16-01.

A PLK4 mutation causing azoospermia in a man with Sertoli cell-only syndrome

About 15% of couples wishing to have children are infertile; approximately half these cases involve a male factor. Polo-like kinase 4 (PLK-4) is a member of the polo protein family and a key regulator of centriole duplication. Male mice with a point mutation in the Plk4 gene show azoospermia associated with germ cell loss. Mutational analysis of 81 patients with azoospermia and Sertoli cell-only syndrome (SCOS) identified one man with a heterozygous 13-bp deletion in the Ser/Thr kinase domain of PLK4. Division of centrioles occurred in wild-type PLK4-transfected cells, but was hampered in PLK-4-mutant transfectants, which also showed abnormal nuclei. Thus, this PLK4 mutation might be a cause of human SCOS and nonobstructive azoospermia.

Sendai virus-mediated gene transfer of the c-myc suppressor far-upstream element-binding protein-interacting repressor suppresses head and neck cancer

Far-upstream element-binding protein-interacting repressor (FIR) is a transcription factor that inhibits c-Myc expression and has been shown to have antitumor effects in some malignancies. Here, we evaluated the antitumor effects of FIR using fusion gene-deleted Sendai virus (SeV/ΔF) as a nontransmissible vector against head and neck squamous cell carcinoma (HNSCC). Using in vitro and in vivo xenograft mouse models, we observed efficient expression of green fluorescent protein (GFP) following transduction with the SeV/ΔF vector encoding GFP (GFP-SeV/ΔF) into HNSCC cells. In vitro and in vivo studies revealed that administration of the FIR-encoded SeV/ΔF (FIR-SeV/ΔF) vector exerted significant antitumor effects, suppressed c-Myc expression and induced apoptosis in HNSCC. Additionally, the antitumor effects of FIR or the expression of GFP following administration of the FIR- or GFP-SeV/ΔF vector, respectively, were dependent on the multiplicity of infection or titer. Furthermore, the SeV/ΔF vector itself had no cytotoxic effects. Therefore, the SeV/ΔF vector may be safe and useful for the treatment of HNSCC, allowing for high-titer SeV/ΔF vector administration for anticancer gene therapy. In addition, SeV/ΔF vector-mediated FIR gene therapy demonstrated effective tumor suppression in HNSCC, suggesting that this therapy may have the potential for clinical use as a novel strategy for HNSCC treatment.

SIN3A mutations are rare in men with azoospermia

A loss of function of the murine Sin3A gene resulted in male infertility with Sertoli cell-only syndrome (SCOS) phenotype in mice. Here, we investigated the relevance of this gene to human male infertility with azoospermia caused by SCOS. Mutation analysis of SIN3A in the coding region was performed on 80 Japanese patients. However, no variants could be detected. This study suggests a lack of association of SIN3A gene sequence variants with azoospermia caused by SCOS in humans.

Removal of reprogramming transgenes improves the tissue reconstitution potential of keratinocytes generated from human induced pluripotent stem cells

Human induced pluripotent stem cell (hiPSC) lines have a great potential for therapeutics because customized cells and organs can be induced from such cells. Assessment of the residual reprogramming factors after the generation of hiPSC lines is required, but an ideal system has been lacking. Here, we generated hiPSC lines from normal human dermal fibroblasts with piggyBac transposon bearing reprogramming transgenes followed by removal of the transposon by the transposase. Under this condition, we compared the phenotypes of transgene-residual and -free hiPSCs of the same genetic background. The transgene-residual hiPSCs, in which the transcription levels of the reprogramming transgenes were eventually suppressed, were quite similar to the transgene-free hiPSCs in a pluripotent state. However, after differentiation into keratinocytes, clear differences were observed. Morphological, functional, and molecular analyses including single-cell gene expression profiling revealed that keratinocytes from transgene-free hiPSC lines were more similar to normal human keratinocytes than those from transgene-residual hiPSC lines, which may be partly explained by reactivation of residual transgenes upon induction of keratinocyte differentiation. These results suggest that transgene-free hiPSC lines should be chosen for therapeutic purposes.

Derivation of human differential photoreceptor cells from adult human dermal fibroblasts by defined combinations of CRX, RAX, OTX2 and NEUROD

Redirecting differentiation of somatic cells by over-expression of transcription factors is a promising approach for regenerative medicine, elucidation of pathogenesis and development of new therapies. We have previously defined a transcription factor combination, that is, CRX, RAX and NEUROD, that can generate photosensitive photoreceptor cells from human iris cells. Here, we show that human dermal fibroblasts are differentiated to photoreceptor cells by the same transcription factor combination as human iris cells. Transduction of a combination of the CRX, RAX and NEUROD genes up-regulated expression of the photoreceptor-specific genes, recoverin, blue opsin and PDE6C, in all three strains of human dermal fibroblasts that were tested. Additional OTX2 gene transduction increased up-regulation of the photoreceptor-specific genes blue opsin, recoverin, S-antigen, CNGB3 and PDE6C. Global gene expression data by microarray analysis further showed that photoreceptor-related functional genes were significantly increased in induced photoreceptor cells. Functional analysis, that is, patch-clamp recordings, clearly revealed that induced photoreceptor cells from fibroblasts responded to light. Both the NRL gene and the NR2E3 gene were endogenously up-regulated in induced photoreceptor cells, implying that exogenous CRX, RAX, OTX2 and NEUROD, but not NRL, are sufficient to generate rod photoreceptor cells.

An efficient method for differentiation of human induced pluripotent stem cells into hepatocyte-like cells retaining drug metabolizing activity

The use of human induced pluripotent stem (iPS) cells would be of great value for a variety of applications involving drug development studies. Several reports have been published on the differentiation of human iPS cells into hepatocyte-like cells; however, the cells were insufficient for application in drug metabolism studies. In this study, we aimed to establish effective methods for differentiation of human iPS cells into hepatocytes. Two human iPS cell lines were differentiated by addition of activin A, dimethyl sulfoxide, hepatocyte growth factor, oncostatin M, and dexamethasone. The differentiated cells expressed hepatocyte markers and drug-metabolizing enzymes, revealing that the human iPS cells were differentiated into hepatocyte-like cells. Expression of CYP3A4 and UGT1A1 mRNAs increased with treatment with typical inducers of the enzymes, and the response of the cells against the inducers was similar to that of human hepatocytes. Furthermore, the drug-metabolizing activity of CYP3A4, as monitored by testosterone 6β-hydroxylase activity, was elevated by these inducers. In conclusion, we established methods for differentiation of hepatocyte-like cells expressing drug metabolizing activity from human iPS cells. The hepatocyte-like cells derived from human iPS cells will be useful for drug metabolism studies.

Establishment and directed differentiation of induced pluripotent stem cells from glycogen storage disease type Ib patient

Glycogen storage disease type Ib (GSDIb) is caused by a deficiency in the glucose-6-phosphate transporter (G6PT), which leads to neutrophil dysfunction. However, the underlying causes of these dysfunctions and their relationship with glucose homeostasis are unclear. Induced pluripotent stem cells (iPSCs) hold a great promise for advances in developmental biology, cell-based therapy and modeling of human disease. Here, we examined the use of iPSCs as a model for GSDIb. In this study, one 2-year-old patient was genetically screened and diagnosed with GSDIb. We established iPSCs and differentiated these cells into hepatocytes and neutrophils, which comprise the main pathological components of GSDIb. Cells that differentiated into hepatocytes exhibited characteristic albumin secretion and indocyanine green uptake. Moreover, iPSC-derived cells generated from patients with GSDIb metabolic abnormalities recapitulated key pathological features of the diseases affecting the patients from whom they were derived, such as glycogen, lactate, pyruvate and lipid accumulation. Cells that were differentiated into neutrophils also showed the GSDIb pathology. In addition to the expression of neutrophil markers, we showed increased superoxide anion production, increased annexin V binding and activation of caspase-3 and caspase-9, consistent with the GSDIb patient's neutrophils. These results indicate valuable tools for the analysis of this pathology and the development of future treatments.

Human cytomegalovirus induces apoptosis in neural stem/progenitor cells derived from induced pluripotent stem cells by generating mitochondrial dysfunction and endoplasmic reticulum stress

Background

Congenital human cytomegalovirus (HCMV) infection, a leading cause of birth defects, is most often manifested as neurological disorders. The pathogenesis of HCMV-induced neurological disorders is, however, largely unresolved, primarily because of limited availability of model systems to analyze the effects of HCMV infection on neural cells.

Methods

An induced pluripotent stem cell (iPSC) line was established from the human fibroblast line MRC5 by introducing the Yamanaka’s four factors and then induced to differentiate into neural stem/progenitor cells (NSPCs) by dual inhibition of the SMAD signaling pathway using Noggin and SB-431542.

Results

iPSC-derived NSPCs (NSPC/iPSCs) were susceptible to HCMV infection and allowed the expression of both early and late viral gene products. HCMV-infected NSPC/iPSCs underwent apoptosis with the activation of caspase-3 and −9 as well as positive staining by the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL). Cytochrome c release from mitochondria to cytosol was observed in these cells, indicating the involvement of mitochondrial dysfunction in their apoptosis. In addition, phosphorylation of proteins involved in the unfolded protein response (UPR), such as PKR-like eukaryotic initiation factor 2a kinase (PERK), c-Jun NH2-terminal kinase (JNK), inositol-requiring enzyme 1 (IRE1), and the alpha subunit of eukaryotic initiation factor 2 (eIF2α) was observed in HCMV-infected NSPC/iPSCs. These results, coupled with the finding of increased expression of mRNA encoding the C/EBP-homologous protein (CHOP) and the detection of a spliced form of X-box binding protein 1 (XBP1) mRNA, suggest that endoplasmic reticulum (ER) stress is also involved in HCMV-induced apoptosis of these cells.

Conclusions

iPSC-derived NSPCs are thought to be a useful model to study HCMV neuropathogenesis and to analyze the mechanisms of HCMV-induced apoptosis in neural cells.

A synthetic nanofibrillar matrix promotes in vitro hepatic differentiation of embryonic stem cells and induced pluripotent stem cells

Embryonic stem (ES) cells recapitulate normal developmental processes and serve as an attractive source for routine access to a large number of cells for research and therapies. We previously reported that ES cells cultured on M15 cells, or a synthesized basement membrane (sBM) substratum, efficiently differentiated into an endodermal fate and subsequently adopted fates of various digestive organs, such as the pancreas and liver. Here, we established a novel hepatic differentiation procedure using the synthetic nanofiber (sNF) as a cell culture scaffold. We first compared endoderm induction and hepatic differentiation between murine ES cells grown on sNF and several other substrata. The functional assays for hepatocytes reveal that the ES cells grown on sNF were directed into hepatic differentiation. To clarify the mechanisms for the promotion of ES cell differentiation in the sNF system, we focused on the function of Rac1, which is a Rho family member protein known to regulate the actin cytoskeleton. We observed the activation of Rac1 in undifferentiated and differentiated ES cells cultured on sNF plates, but not in those cultured on normal plastic plates. We also show that inhibition of Rac1 blocked the potentiating effects of sNF on endoderm and hepatic differentiation throughout the whole differentiation stages. Taken together, our results suggest that morphological changes result in cellular differentiation controlled by Rac1 activation, and that motility is not only the consequence, but is also able to trigger differentiation. In conclusion, we believe that sNF is a promising material that might contribute to tissue engineering and drug delivery.

Differentiation of human induced pluripotent stem cells into functional enterocyte-like cells using a simple method

  Human induced pluripotent stem (iPS) cells were differentiated into the endoderm using activin A and were then treated with fibroblast growth factor 2 (FGF2) for differentiation into intestinal stem cell-like cells. These immature cells were then differentiated into enterocyte-like cells using epidermal growth factor (EGF) in 2% fetal bovine serum (FBS). At the early stage of differentiation, mRNA expression of caudal type homeobox 2 (CDX2), a major transcription factor related to intestinal development and differentiation, and leucine-rich repeat-containing G-protein-coupled receptor 5 (LGR5), an intestinal stem cell marker, was markedly increased by treatment with FGF2. When cells were cultured in medium containing EGF and a low concentration of FBS, mRNAs of specific markers of intestinal epithelial cells, including sucrase-isomaltase, the intestinal oligopeptide transporter SLC15A1/peptide transporter 1 (PEPT1), and the major metabolizing enzyme CYP3A4, were expressed. In addition, sucrase-isomaltase protein expression and uptake of β-Ala-Lys-N-7-amino-4-methylcoumarin-3-acetic acid (β-Ala-Lys-AMCA), a fluorescence-labeled substrate of the oligopeptide transporter, were detected. These results demonstrate a simple and direct method for differentiating human iPS cells into functional enterocyte-like cells.

Stability of genomic imprinting in human induced pluripotent stem cells

BACKGROUND

hiPSCs are generated through epigenetic reprogramming of somatic tissue. Genomic imprinting is an epigenetic phenomenon through which monoallelic gene expression is regulated in a parent-of-origin-specific manner. Reprogramming relies on the successful erasure of marks of differentiation while maintaining those required for genomic imprinting. Loss of imprinting (LOI), which occurs in many types of malignant tumors, would hinder the clinical application of hiPSCs.

RESULTS

We examined the imprinting status, expression levels and DNA methylation status of eight imprinted genes in five independently generated hiPSCs. We found a low frequency of LOI in some lines. Where LOI was identified in an early passage cell line, we found that this was maintained through subsequent passages of the cells. Just as normal imprints are maintained in long-term culture, this work suggests that abnormal imprints are also stable in culture.

CONCLUSIONS

Analysis of genomic imprints in hiPSCs is a necessary safety step in regenerative medicine, with relevance both to the differentiation potential of these stem cells and also their potential tumorigenic properties.

Relationship between glomerular filtration rate and plasma N-terminal pro B-type natriuretic peptide concentrations in dogs with chronic kidney disease

Plasma N-terminal pro B-type natriuretic peptide (NT-proBNP) concentrations increase in dogs with azotemia. However, the correlation between glomerular filtration rate (GFR) and NT-proBNP concentrations in dogs has not been evaluated. The objective of this study was to evaluate the correlation between GFR and plasma NT-proBNP concentrations in dogs with chronic kidney disease (CKD). In this retrospective cross-sectional study, plasma creatinine (Cre) and NT-proBNP concentrations, plasma iohexol clearance (PCio) values and blood pressure were measured in dogs with CKD. Dogs were classified according to PCio values into D group (dogs with decreased PCio values), and N group (dogs with normal PCio values). Dogs were further categorized on the basis of their systolic blood pressure and PCio values into NT-D group (normotensive dogs with decreased PCio values), NT-N group (normotensive dogs with normal PCio values), HT-D group (hypertensive dogs with decreased PCio values) and HT-N group (hypertensive dogs with normal PCio values). Significant correlations were observed between plasma NT-proBNP and Cre concentrations (r=0.360, P<0.05) and PCio values (r=-0.470, P<0.01). Plasma NT-proBNP concentrations were significantly higher in the D group than in the N group (P<0.001). Plasma NT-proBNP concentrations were significantly higher in the HT-D group than in the other three groups (P ≤ 0.007). No differences in plasma NT-proBNP concentrations were observed between the NT-D and HT-N groups (P=0.28). Plasma NT-proBNP concentrations were significantly lower in the NT-N group than in the other three groups (P ≤ 0.043). Our findings suggest that decreased GFR might be associated with increased plasma NT-proBNP concentrations in dogs, similar to that in humans. In addition, the complication of hypertension in CKD might be associated with further increases in plasma NT-proBNP concentrations. In conclusion, the effects of GFR and blood pressure on the plasma NT-proBNP concentration were small, but it could be necessary to consider the effects when this marker is used to evaluate canine cardiac disease.

Coexpression of Escherichia coli RNase III in silkworm cells improves the efficiency of RNA interference induced by long hairpin dsRNAs

Long hairpin dsRNA transcribed from chromosomal DNA can induce RNA interference in Bombyx mori cells, although its gene silencing efficiency is lower than that of exogenously introduced double-stranded RNAs (dsRNAs). To solve this problem, we monitored the nuclear cytoplasmic translocation of the transcribed hairpin dsRNA and analyzed the processing efficiency into mature small interfering RNA (siRNA). Northern blot analysis revealed that the transcribed hairpin dsRNAs were spliced and transported into the cytoplasm, but were not effectively diced into siRNAs. Interestingly, RNAi with hairpin dsRNAs from genome-integrated IR transgene was stimulated by the coexpression of Escherichia coli RNase III, although this exogenous enzyme seemed to bring about nonspecific cleavage of cellular mRNA.

Induction of adipogenic differentiation in three-dimensional culture model on a novel microfabricated scaffold

The development of a three-dimensional (3D) culture system is very important for regenerative medicine and drug discovery applications of stem cell technology because the 3D culture condition could mimic the stem cell environment in vivo and support accurate differentiation. This chapter describes a novel 3D culture technique for efficient induction of adipogenic differentiation. This 3D culture system provides an easy way to allow cells to form a 3D spheroid structure without any matrix derived from animal and chemical substances. We firstly describe the details of the 3D culture technique using human mesenchymal stem/progenitor cells (MPCs) and its optimization. Then we elaborate on the protocol of efficient induction for adipogenic differentiation and adipocyte-specific gene expression, including peroxisome proliferator-activated receptor-γ, with our culture system in human MPCs.

ZNF385B is characteristically expressed in germinal center B cells and involved in B-cell apoptosis

We previously identified zinc finger (ZF) protein ZNF385B as a molecule specifically expressed in Burkitt's lymphoma (BL) among hematologic malignancies. Here, we investigated ZNF385B expression in healthy B cells in a variety of hematological tissues by RT-PCR and immunohistochemistry. ZNF385B expression was found to be limited to a subset of GC B cells, the healthy counterpart to BL B cells. To elucidate the function of ZNF385B in healthy B cells, we established a tetracycline-controlled protein-inducible system in B-cell lines and observed that ectopic expression of the longest transcript variant of ZNF385B, possessing four ZF domains, induced upregulation of PERP and FAS/CD95, a downstream target of p53, and activation of caspase, resulting in apoptosis induction. However, a ZNF385B deletion mutant with three ZF domains corresponding to shorter isoforms, did not induce upregulation; rather it inhibited apoptosis induced by CD20 cross-linking and BCR stimulation. The direct binding of ZNF385B with p53 has suggested the involvement of ZNF385B in B-cell apoptosis via modulation of p53 transactivation; our data indicate that ZNF385B characteristically expressed in GC B cells has both proapoptotic and antiapoptotic activities depending on the type of isoform and should be a novel player in GC B-cell selection.