An alternative method for the isolation of NS-1 hybridomas using cholesterol auxotrophy of NS-1 mouse myeloma cells

Structure-based design of a novel third-generation antipsychotic drug lead with potential antidepressant properties

Partial agonist activity at the dopamine D₂ receptor (DRD2) is a key feature of third-generation antipsychotics (TGAs). However, TGAs also act as antagonists or weak partial agonists to the serotonin (5-hydroxytryptamine; 5-HT) 2A receptor (5-HT_2AR). Here we present the crystal structures of aripiprazole- and cariprazine-bound human 5-HT_2AR. Both TGAs adopt an unexpected 'upside-down' pose in the 5-HT_2AR binding pocket, with secondary pharmacophores inserted in a similar way to a 'bolt'. This insight into the binding modes of TGAs offered a structural mechanism underlying their varied partial efficacies at 5-HT_2AR and DRD2. These structures enabled the design of a partial agonist at DRD2/3 and 5-HT_1AR with negligible 5-HT_2AR binding that displayed potent antipsychotic-like activity without motor side effects in mice. This TGA lead also had antidepressant-like effects and improved cognitive performance in mouse models via 5-HT_1AR. This work indicates that 5-HT_2AR affinity is a dispensable contributor to the therapeutic actions of TGAs.

Induction of integration-free human-induced pluripotent stem cells under serum- and feeder-free conditions

Human-induced pluripotent stem cells (hiPSCs) have shown great potential toward practical and scientific applications. We previously reported the generation of human dental pulp stem cells using non-integrating replication-defective Sendai virus (SeVdp) vector in feeder-free culture with serum-free medium hESF9. This study describes the generation of hiPSCs from peripheral blood mononuclear cells to increase the donor population, while reducing biopsy invasiveness. From 6-d-old primary culture of peripheral blood mononuclear cells (PBMCs) with IL-2, hiPSCs were established using SeVdp(KOSM)302L with recombinant Laminin-511 E8 fragments under serum-free condition. The established PBMC-derived hiPSCs showed pluripotency and differentiation ability both in vivo and in vitro. In addition, we evaluated microarray data from PBMC- and dental pulp–derived hiPSCs. These hiPSCs will be beneficial for characterizing the molecular mechanisms of cellular differentiation and may provide useful substrates for developing cellular therapeutics.

Generation of cleidocranial dysplasia-specific human induced pluripotent stem cells in completely serum-, feeder-, and integration-free culture

Human pluripotent stem cells hold great promise for their practical and scientific potentials. To improve understanding of self-renewal and differentiation, we previously reported a defined serum-free medium hESF9 could generate and maintain human induced pluripotent stem cells (iPSCs) in serum- and feeder-free culture conditions using retroviral vectors. To avoid the unpredictable side effects associated with retrovirus integration, we report here the successful generation of hiPSCs from dental pulp cells with a non-integrating replication-defective and persistent Sendai virus (SeVdp) vector expressing four key reprogramming genes. We found that hESF9 medium in combination with fibronectin are effective for generating and maintaining hiPSCs with SeVdp (KOSM). Using this system, pluripotent and self-renewing hiPSCs could be easily and stably generated and propagated. With this system, we successfully generated hiPSCs from cleidocranial dysplasia (CCD) caused by a heterozygous germ-line mutation of runt-related protein2 (RUNX2), which has an important role in the differentiation of osteoblasts and maturation of chondrocytes. This is the first report of the establishment of CCD-specific iPSCs. The cartilage in the teratomas of CCD-iPSCs showed abnormalities. These CCD-iPSCs would be beneficial to clarify the molecular mechanism and for development of medical applications. Moreover, it brings new pathophysiological role of RUNX2 in the differentiation of the human chondrocytes and osteocytes.

Generation of human induced pluripotent stem (Ips) cells in serum- and feeder-free defined culture and TGF-Β1 regulation of pluripotency

Human Embryonic Stem cells (hESCs) and human induced Pluripotent Stem cells (hiPSCs) are commonly maintained on inactivated mouse embryonic fibroblast as feeder cells in medium supplemented with FBS or proprietary replacements. Use of culture medium containing undefined or unknown components has limited the development of applications for pluripotent cells because of the relative lack of knowledge regarding cell responses to differentiating growth factors. In addition, there is no consensus as to the optimal formulation, or the nature of the cytokine requirements of the cells to promote their self-renewal and inhibit their differentiation. In this study, we successfully generated hiPSCs from human dental pulp cells (DPCs) using Yamanaka's factors (Oct3/4, Sox2, Klf4, and c-Myc) with retroviral vectors in serum- and feeder-free defined culture conditions. These hiPSCs retained the property of self-renewal as evaluated by the expression of self-renewal marker genes and proteins, morphology, cell growth rates, and pluripotency evaluated by differentiation into derivatives of all three primary germ layers in vitro and in vivo. In this study, we found that TGF-β1 increased the expression levels of pluripotency markers in a dose-dependent manner. However, increasing doses of TGF-β1 suppressed the growth rate of hiPSCs cultured under the defined conditions. Furthermore, over short time periods the hiPSCs cultured in hESF9 or hESF9T exhibited similar morphology, but hiPSCs maintained in hESF9 could not survive beyond 30 passages. This result clearly confirmed that hiPSCs cultured in hESF9 medium absolutely required TGF-β1 to maintain pluripotency. This simple serum-free adherent monoculture system will allow us to elucidate the cell responses to growth factors under defined conditions and can eliminate the risk might be brought by undefined pathogens.

Long-term culture of Xenopus presumptive ectoderm in a nutrient-supplemented culture medium

Animal cap assay is a useful experimental model for investigating the activity of inducers in amphibian development. This assay has revealed that activin A is a potent mesoderm-inducing factor. However, it has been very difficult to induce highly differentiated tissues such as cartilage in a 3-4 day culture period. It was recently reported that jaw cartilage was induced in vitro in an animal cap that had been cultured for 14 days in Steinberg's solution using the sandwich culture method and activin A. Under these conditions, necrosis was occasionally observed in the explants. In this study, we have achieved long-term animal cap cultures in a nutrient-supplemented culture medium designated RDX. This medium was made by modifying the saline concentration of the RD medium previously developed as a basal medium for the serum-free culture of various kinds of mammalian cells. The explants cultured in RDX grew more vigorously compared with those in Steinberg's solution. RDX medium promoted a wider variety of tissue induction and gene expression in the animal caps than Steinberg's solution, and also increased the frequency of cartilage induction. Therefore, the supplemental nutrients may support and promote the differentiation of cartilage. This long-term culture method using RDX medium is useful for studying the differentiation of tissues or organs such as cartilage in vitro.

Prognostic value of epidermal growth factor receptor (EGFR) and its relationship to the estrogen receptor status in 1029 patients with breast cancer

An epidermal growth factor receptor (EGFR) has been reported to be associated with a poor clinical outcome in breast cancer, while its prognostic value remains controversial. Immunohistochemical staining for EGFR was performed on frozen sections of primary breast cancer from 1029 patients with a mean follow-up duration of 46 months. EGFR was positive in 277 (26.9%) of 1029 cases which inversely correlated with the estrogen receptor (ER) status. A univariated analysis indicated that EGFR had a significant prognostic value in both the disease free survival (DFS) and the overall survival (OS), while the same effect was also found in node negative as well as node positive breast cancer. A multivariate analysis indicated that EGFR was an independently significant prognostic factor for DFS (p = 0.0174) and OS (p = 0.0105) in all patients, but that EGFR demonstrated a prognostic significance only for DFS (p = 0.0241) in node negative and only for OS (p = 0.0333) in node positive breast cancer. When all patients were stratified for EGFR and ER, a multivariate analysis indicated that the combination of EGFR(+)/ER(-) was an independently significant factor for both DFS and OS in node negative as well as node positive breast cancer. In conclusion, the prognostic value of EGFR was demonstrated by a multivariate analysis in a large series of breast cancer patients, but the value of EGFR was somewhat insufficient to achieve statistical significance for both DFS and OS in the subgroups divided by nodal status. On the other hand, the prognostic value of combination of EGFR and ER was sufficient to achieve statistical significance based on a multivariate analysis for both DFS and OS in the subgroups of node negative as well as node positive breast cancer patients.

An antigen capture assay for the measurement of serum clusterin concentrations

We have developed and validated a robust antigen capture assay for the measurement of serum clusterin. Increased clusterin expression, and alterations in serum clusterin levels have been associated with a number of disease states. In particular, clusterin has been shown to be associated with tissue regression and apoptosis in the rat ventral prostate in response to androgen ablation or administration of anti-androgens. The object of this study was to determine if changes in human serum clusterin can be used as a diagnostic or prognostic marker to monitor the response to hormonal therapy in patients with prostate cancer, and to determine if clusterin concentrations increase with the progression towards androgen independence. The antigen capture assay was used for an extensive analysis of human serum clusterin concentration in fasting males, and to determine if there is any relationship between clusterin and age or cholesterol levels. The average clusterin level in serum is 101+/-42 microg/ml (n=96). There is no correlation to age or serum cholesterol levels. Analysis of serum clusterin levels in patients with newly diagnosed prostate cancer (n=5), hormone responsive tumors (n=5), and hormone refractory disease (n=5), demonstrates that no significant changes in serum clusterin levels accompany the progression of prostatic disease, or response to hormone therapy.

The effects of oestrogen on osteocalcin production by human periodontal ligament cells

The purpose was to investigate the effects of oestradiol on the function of periodontal ligament (PDL) cells by measuring the production of osteocalcin in vitro. Cells were obtained from the healthy periodontal ligament of teeth extracted from two males and two females for orthodontic reasons. Serum-free medium was used when testing the effects of oestradiol on PDL cells. The amount of osteocalcin in the culture medium was analysed by two-step sandwich enzyme immunoassay in the presence or absence of oestradiol. It was shown that oestradiol enhanced the production of osteocalcin by PDL cells in a time- and dose-dependent manner. PDL cells obtained from both male and female donors were affected by oestradiol. It thus appears that oestradiol is one of the factors important for PDL cells to express their function.

Effects of insulin and transferrin on the generation of lymphokine-activated killer cells in serum-free medium

We have developed a serum-free medium designated RDSF for the generation of LAK cells based on RD6F medium, which was originally developed as a serum-free medium for the growth of myeloma and hybridoma cells. The cytotoxic activity of LAK cells generated in RDSF against Raji, K562 and oral cancer cells, is 3-4 times that of LAK cells generated in medium containing 10% human type AB serum. RDSF medium consisted of nutrient mixture supplemented with transferrin, 2-aminoethanol, 2-mercaptoethanol, sodium selenite and interleukin-2. In this study, we have found that insulin which has been shown to be the most important polypeptide hormone in serum-free media for animal cells, inhibited the generation of cytotoxic activity of LAK cells cultured from peripheral blood lymphocytes. In addition, we found that transferrin was an essential component for the growth and generation of LAK cells in serum-free culture. These results suggest that RDSF may be useful in adoptive immunotherapy for cancer as well as for studying factors involved in the growth and differentiation of LAK cells.

Immunohistochemical localization of fibroblast growth factor-1 (FGF-1) and FGF-2 in cultured human ameloblastoma epithelial cells and ameloblastoma tissues

Fibroblast growth factor-1 (FGF-1) and FGF-2 are mitogenic polypeptides that may contribute to neoplastic cell proliferation. In the present study, we established a serum-free culture system for ameloblastoma cells and demonstrated that the addition of FGF-1 and FGF-2 enhanced cell growth in a dose-dependent manner. Immunoperoxidase staining of cultured cells demonstrated strong expression of FGF-1 and FGF-2. In tissue specimens, FGF-1 was localized in epithelial cell components of ameloblastomas, whereas FGF-2 was mainly found in the basement membranes with only moderate staining in epithelium. These data suggest that both FGF-1 and FGF-2 may contribute to the growth and development of ameloblastomas.

Immunocytochemical localization of fibroblast growth factor-1 (FGF-1) and FGF-2 in oral squamous cell carcinoma (SCC)

The localization of fibroblast growth factor-1 (FGF-1) and FGF-2 in human oral squamous cell carcinoma (SCC) was examined by immunohistochemical techniques using anti-FGF-1 and anti-FGF-2 monoclonal antibodies. Immunofluorescence staining of two oral SCC cell lines revealed that growing cancer cells were intensely positive for both FGF-1 and FGF-2, but confluent cells showed a faint immunostaining. In addition, two molecular mass species of FGF-1 (16 and 18 kDa) and one of FGF-2 (18 kDa) were identified by Western blot in cell extracts derived from growing SCC cells, but not from confluent SCC cells. The growing cell extracts significantly stimulated the proliferation of human umbilical vein endothelial cells. Immunoperoxidase staining of 13 oral SCC cases showed that both well-differentiated and poorly-differentiated cancer cells were positive for FGF-1 and FGF-2 with high frequency and intensity as compared to normal oral epithelium. These results indicate that SCC cells express high levels of endogenous FGF-1 and FGF-2, and suggest that these growth factors may contribute to cancer cell growth.