Up-regulation of protein serine/threonine phosphatase type 2C during 1α,25-dihydroxyvitamin D3-induced monocytic differentiation of leukemic HL-60 cells

AbstractTreatment with 20 nM 1α,25-dihydroxyvitamin D3 (1,25(OH)2D3) caused a progressive increase in the activity of Mg2+-dependent protein serine/threonine phosphatase type 2C (PP2C) in subcellular fractions of HL-60 cells, whereas PP2C activity was relatively constant throughout all-trans retinoic acid-induced (1 μM) granulocytic differentiation. The increase in PP2C activity appeared to parallel the 1,25(OH)2D3-induced phenotypic and functional changes in HL-60 cells. Immunoblot and Northern blot analysis indicated that the increase in PP2C activity corresponded to the increased expression of PP2C protein, which was preceded by an increase in the level of mRNA for PP2Cβ. No mRNA for PP2Cα was detected in resting or 1,25(OH)2D3-stimulated HL-60 cells. These results suggest that the increased expression of PP2C is related with the 1,25(OH)2D3-induced monocytic differentiation of HL-60 cells

A contactless electrical stimulator: application to fabricate functional skeletal muscle tissue

Engineered skeletal muscle tissues are ideal candidates for applications in drug screening systems, bio-actuators, and as implantable constructs in tissue engineering. Electrical field stimulation considerably improves the differentiation of muscle cells to muscle myofibers. Currently used electrical stimulators often use direct contact of electrodes with tissue constructs or their culture medium, which may cause hydrolysis of the culture medium, joule heating of the medium, contamination of the culture medium due to products of electrodes corrosion, and surface fouling of electrodes. Here, we used an interdigitated array of electrodes combined with an isolator coverslip as a contactless platform to electrically stimulate engineered muscle tissue, which eliminates the aforementioned problems. The effective stimulation of muscle myofibers using this device was demonstrated in terms of contractile activity and higher maturation as compared to muscle tissues without applying the electrical field. Due to the wide array of potential applications of electrical stimulation to two- and three-dimensional (2D and 3D) cell and tissue constructs, this device could be of great interest for a variety of biological applications as a tool to create noninvasive, safe, and highly reproducible electric fields.World Premier International Research Center Initiative (WPI

Direct tumor recognition by a human CD4(+) T-cell subset potently mediates tumor growth inhibition and orchestrates anti-tumor immune responses.

Tumor antigen-specific CD4(+) T cells generally orchestrate and regulate immune cells to provide immune surveillance against malignancy. However, activation of antigen-specific CD4(+) T cells is restricted at local tumor sites where antigen-presenting cells (APCs) are frequently dysfunctional, which can cause rapid exhaustion of anti-tumor immune responses. Herein, we characterize anti-tumor effects of a unique human CD4(+) helper T-cell subset that directly recognizes the cytoplasmic tumor antigen, NY-ESO-1, presented by MHC class II on cancer cells. Upon direct recognition of cancer cells, tumor-recognizing CD4(+) T cells (TR-CD4) potently induced IFN-γ-dependent growth arrest in cancer cells. In addition, direct recognition of cancer cells triggers TR-CD4 to provide help to NY-ESO-1-specific CD8(+) T cells by enhancing cytotoxic activity, and improving viability and proliferation in the absence of APCs. Notably, the TR-CD4 either alone or in collaboration with CD8(+) T cells significantly inhibited tumor growth in vivo in a xenograft model. Finally, retroviral gene-engineering with T cell receptor (TCR) derived from TR-CD4 produced large numbers of functional TR-CD4. These observations provide mechanistic insights into the role of TR-CD4 in tumor immunity, and suggest that approaches to utilize TR-CD4 will augment anti-tumor immune responses for durable therapeutic efficacy in cancer patients

Intracellular electrochemical sensing

Observing biochemical processes within living cell is imperative for biological and medical research. Fluoresce imaging is widely used for intracellular sensing of cell membranes, nuclei, lysosomes, and pH. Electrochemical assays have been proposed as an alternative to fluorescence-based assays because of excellent analytical features of electrochemical devices. Notably, thanks to the rapid progress of micro/nanotechnologies and electrochemical techniques, intracellular electrochemical sensing is making rapid progress, leading to a successful detection of intracellular components. Such insight can provide a deep understanding of cellular biological processes and, ultimately, define the human healthy and diseased states. In this review, we present an overview of recent research progress in intracellular electrochemical sensing. We focus on two main topics, electrochemical extraction of cytosolic contents from cells and intracellular electrochemical sensing in situ.Observing biochemical processes within living cell is imperative for biological and medical research. Fluoresce imaging is widely used for intracellular sensing of cell membranes, nuclei, lysosomes, and pH. Electrochemical assays have been proposed as an alternative to fluorescence‐based assays because of excellent analytical features of electrochemical devices. Notably, thanks to the rapid progress of micro/nanotechnologies and electrochemical techniques, intracellular electrochemical sensing is making rapid progress, leading to a successful detection of intracellular components. Such insight can provide a deep understanding of cellular biological processes and, ultimately, define the human healthy and diseased states. In this review, we present an overview of recent research progress in intracellular electrochemical sensing. We focus on two main topics, electrochemical extraction of cytosolic contents from cells and intracellular electrochemical sensing in situ

Modern T cell technologies for immunotherapy of solid tumors

According to the common concept of immune editing, the interaction of malignant tumor cells and immune system is a complex multifactorial process, which may result in both antitumor effector activity and development of suppressor mechanisms that promote tumor growth. Accumulation of scientific knowledge in the field of studying the antitumor immune response and tolerance has led to emergence of many research and therapeutic approaches that use different components of the immune system to combat neoplastic processes. Along with currently available approaches, there are strategies that use the potential of antigen-specific T lymphocytes, the main effectors of adaptive immunity, in order to fight malignant neoplasms which appeared more than a century ago and have built the scientific basis of cancer immunotherapy. One line of evidence of the significant antitumor potential of T cells in immunotherapeutic schemes for the cancer treatment was presented by successful therapy of hemato-oncological diseases, achieved at the end of the past decade. At the same time, however, the therapy of solid malignant neoplasms still faces significant difficulties that limit the efficiency of treatment. In this regard, the main objective of the review is to accumulate up-to-date information on the successes and limitations of T cell immunotherapy in the patients with solid tumors. To date, the phenotype and functionality of T cells is being investigated and modulated both towards enhancing antitumor cytotoxicity, increasing viability and proliferative activity of T cells, and in overcoming the immunosuppressive effect of the tumor and its tolerogenic microenvironment upon T cells, as well as ensuring targeted migration of the effector T cells to the malignant tissues. This review discusses immunotherapeutic approaches exploiting the potential of effector T lymphocytes, e.g., current clinical trials or applied therapeutic regimens for the treatment of solid malignant neoplasms. Antigen-independent approaches aimed at nonspecific enhancement of the T cell responses, i.e., therapy with recombinant cytokines and inhibition of immune checkpoint molecules. Antigendependent, or antigen-specific approaches such as adoptive T cell therapy with endogenous T lymphocytes are also discussed as well as trials on T cells with modified antigen-recognition receptor (CAR-Tcells, TCR-Tcells), like as usage of bispecific antibodies as T cell engagers. The review describes the benefits and disadvantages of these approaches in monotherapy, as well as current results and prospects for their mutual combinations