Research on neurodegenerative diseases using induced pluripotent stem cells

Induced pluripotent stem cells (iPSC) are derived from somatic cells. These somatic cells have had their gene expression experimentally reprogrammed to an embryonic stem cell‐like pluripotent state, gaining the capacity to differentiate various cell types in the three embryonic germ layers. Thus, iPSC technology makes it possible to obtain neuronal cells from any human cells. iPSC can be generated from various kinds of somatic cells and from patients with neurodegenerative diseases. Disease modelling using iPSC technology would elucidate the pathogenesis of such diseases and contribute to related drug discoveries. In this review, we discuss the recent advances in iPSC technology as well as its potential applications.     

A Solid-Phase Assay for the Detection of Anti-Sperm Antibodies

PROBLEM: ELISA is an ideal assay method for a large-scale screening of anti-sperm antibodies among a large number of infertile males. However, conventional ELISA with whole spermatozoa needs time-consuming steps of centrifugation. METHOD: A solid-phase assay used for detecting anti-sperm antibodies was established. This assay is suitable not only for detecting circulating anti-sperm antibodies of IgG, IgM, and IgA subclass simultaneously but also for screening hybridomas secreting anti-sperm monoclonal antibodies (mAbs). The microtiter plates, on which solubilized sperm antigens are fixed, can be stored at ? 80°C for up to six months without losing reactivity with anti-sperm antibodies. RESULTS: Using this assay, 53 sera (13 were proven positive and 40 were proven negative for sperm agglutination antibody) were tested. Although the false-negative rate was 0%, the false-positive rate was 32%. One thousand one hundred sixty-five supernatants from hybridomas constructed with splenocytes of mice who were hyperimmunized with human sperm and nonsecreting myeloma cells were tested by this solid-phase assay and two anti-sperm mAb secreting clones were selected and established. CONCLUSIONS: It is recommended that for research work this assay could be used for the first screening of the hybridoma secreting anti-sperm mAb, and for clinical use this assay might be suitable for the first screening of sera of infertile patients. However, conventional bioassays should follow to confirm the biological meaning of the positivity.     

Bone Marrow‐Derived Cells Implanted into Freeze‐Injured Urinary Bladders Reconstruct Functional Smooth Muscle Layers

Regenerative medicine offers great hope for lower urinary tract dysfunctions due to irreversibly damaged urinary bladders and urethras. Our aim is the utilization of bone marrow‐derived cells to reconstruct smooth muscle layers for the treatments of irreversibly damaged lower urinary tracts. In our mouse model system for urinary bladder regeneration, the majority of smooth muscle layers in about one‐third of the bladder are destroyed by brief freezing. Three days after wounding, we implant cultured cells derived from bone marrow. The implanted bone marrow‐derived cells survive and differentiate into layered smooth muscle structures that remediate urinary dysfunction. However, bone marrow‐derived cells implanted into the intact normal urinary bladders do not exhibit these behaviors. The presence of large pores in the walls of the freeze‐injured urinary bladders is likely to be helpful for a high rate of survival of the implanted cells. The pores could also serve as scaffolding for the reconstruction of tissue structures. The surviving host cells upregulate several growth factor mRNAs that, if translated, can promote differentiation of smooth muscle and other cell types. We conclude that the multipotency of the bone marrow‐derived cells and the provision of scaffolding and suitable growth factors by the microenvironment enable successful tissue engineering in our model system for urinary bladder regeneration. In this review, we suggest that the development of regenerative medicine needs not only a greater understanding of the requirements for undifferentiated cell proliferation and targeted differentiation, but also further knowledge of each unique microenvironment within recipient tissues.