In ethnopharmacology, and especially in traditional Chinese medicine, medicinal plants have been used for thousands of years. Similarly, agricultural plants have been used throughout the history of mankind. The recent development of the genetic engineering of plants to produce plants with desirable features adds a new and growing dimension to humanity’s usage of plants. The biotechnology of plants has come of age and a plethora of bioengineering applications in this context have been delineated during the past few decades. Callus cultures and suspension cell cultures offer a wide range of usages in pharmacology and pharmacy (including Chinese medicine), as well as in agriculture and horticulture. This review provides a timely overview of the advancements that have been made with callus cultures in these scientific fields. Genetically modified callus cultures by gene technological techniques can be used for the synthesis of bioactive secondary metabolites and for the generation of plants with improved resistance against salt, draft, diseases, and pests. Although the full potential of callus plant culture technology has not yet been exploited, the time has come to develop and market more callus culture-based products.

Leukemia relapse is still the leading cause of treatment failure after allogeneic hematopoietic stem cell transplantation (allo-HSCT) for B cell acute lymphoblastic leukemia (B-ALL). Relapsed patients with BALL after allo-HSCT have a very short median survival. Minimal residual disease (MRD) is predictive of forthcoming hematological relapse after hematopoietic stem cell transplantation (HSCT); furthermore, eliminating MRD effectively prevents relapse. Donor lymphoblastic infusion (DLI) is the main established approach to treat B-ALL with MRD after allo-HSCT. However, about one-third of patients with MRD are non-responsive to DLI and their prognosis worsens. Although donor-derived cluster of differentiation (CD)19-directed chimeric antigen receptor-modified (CAR) T cells (CART19s) can potentially cure leukemia, the efficiency and safety of infusions with these cells have not yet been investigated in patients with MRD after HSCT. Between September 2014 and February 2018, six patients each received one or more infusions of CART19s from HSCT donors. Five (83.33%) achieved MRD-negative remission, and one case was not responsive to the administration of CAR T cells. Three of the six patients are currently alive without leukemia. No patient developed acute graft-versus-host disease (aGVHD), and no patient died of cytokine release syndrome. Donor-derived CAR T cell infusions seem to be an effective and safe intervention for patients with MRD in B-ALL after allo-HSCT and for those who were not responsive to DLI.

Pluripotent stem cells (PSCs), including embryonic stem cells (ESCs) and induced PSCs (iPSCs), can differentiate into cells of the three germ layers, suggesting that PSCs have great potential for basic developmental biology research and wide applications for clinical medicine. Genuine ESCs and iPSCs have been derived from mice and rats, but not from livestock such as the pig—an ideal animal model for studying human disease and regenerative medicine due to similarities with human physiologic processes. Efforts to derive porcine ESCs and iPSCs have not yielded high-quality PSCs that can produce chimeras with germline transmission. Thus, exploration of the unique porcine gene regulation network of preimplantation embryonic development may permit optimization of culture systems for raising porcine PSCs. Here we summarize the recent progress in porcine PSC generation as well as the problems encountered during this progress and we depict prospects for generating porcine naive PSCs.

Proteinase-activated receptors (PARs) are a novel subclass of seven transmembrane-spanning, G protein-coupled receptors. PAR-1 and PAR-2 are widely expressed in a variety of cells and are found to be involved in many physiological and pathological processes including inflammation and immune response. However, little is known about the function of PAR-1, 2 in acute graft host disease (GVHD). In the present study, we first detected the expression of PAR-1, 2 protein and mRNA in a murine model of acute GVHD using the methods of immunohistochemistry, Western blot and quantitative real-time polymerase chain reaction (PCR). Syngeneic hematopoietic stem cell transplantation (HSCT) mice served as controls. The relative gene expression level of PAR-1 was significantly increased in the skin, liver, small intestine of allogeneic HSCT mice (in skin: 0.039±0.013 0.008±0.002 of controls, =0.009; in liver: 0.165±0.006 0.017±0.006 of controls, =0.004; in small intestine: 0.215±0.009 0.016±0.002 of controls, =0.003), but not in the stomach, lung and kidney of allogeneic HSCT mice (>0.05). PAR-2 mRNA expression in the liver and small intestine of allogeneic HSCT mice (in liver: 0.010±0.002 0.003±0.001 of controls, =0.008; in small intestine: 0.006±0.001 0.003±0.001 of controls, =0.024) was increased significantly, but PAR-2 mRNA expression in the other organs (>0.05) was not found to be significantly elevated. PAR-1, 2 protein expression was in accordance with the mRNA expression, as shown by Western blot. Using immunohistochemistry the present study demonstrated that there was strong PAR-1, 2 immunoreactivity in the epithelial cell and vascular endothelial cell of target organs of acute GVHD. Our findings of markedly increased expression of PAR-1, 2 in target organs of acute GVHD suggest that PAR-1 and PAR-2 may play an important role in the pathogenesis of acute GVHD.

Human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) possess various advantageous properties, including self-renewal, extended proliferation potential, multi-lineage differentiation potential and capacity for differentiating into sweat gland-like cells in certain conditions. However, little is known about the effect of clinical-grade culture conditions on these properties and on the differentiative potential of hUC-MSCs. In this study, we sought to investigate the properties of hUC-MSCs expanded with animal serum free culture media (ASFCM) in order to determine their potential for differentiation into sweat gland-like cells. We found that primary cultures of hUC-MSCs could be established with ASFCM. Moreover, cells cultured in ASFCM showed vigorous proliferation comparable to those of cells grown in classical culture conditions containing fetal bovine serum (FBS). Morphology of hUC-MSCs cultured in ASFCM was comparable to those of cells grown under classical culture conditions, and hUC-MSCs grown in both of the two culture conditions tested showed the typical antigen profile of MSCs—positive for CD29, CD44, CD90, and CD105, and negative for CD34 and CD45, as expected. Chromosomal aberration assay revealed that the cells were stable after long-term culture under both culture conditions. Like normal cultured MSCs, hUC-MSCs induced under ASFCM conditions exhibited expression of the same markers (CEA, CK14 and CK19) and developmental genes (EDA and EDAR) that are characteristic of normal sweat gland cells. Taken together, our findings indicate that the classical culture medium used to differentiate hUC-MSCs into sweat gland-like cells can be replaced safely by ASFCM for clinical purposes.

Evaluating the effects of novel drugs on appropriate tumor models has become crucial for developing more effective therapies that target highly tumorigenic and drug-resistant cancer stem cell (CSC) populations. In this study, we demonstrate that a subset of cancer cells with CSC properties may be enriched into tumor spheroids under stem cell conditions from a non-small cell lung cancer cell line. Treating these CSC-like cells with gemcitabine alone and a combination of gemcitabine and the novel CHK1 inhibitor PF-00477736 revealed that PF-00477736 enhances the anti-proliferative effect of gemcitabine against both the parental and the CSC-like cell populations. However, the CSC-like cells exhibited resistance to gemcitabine-induced apoptosis. Collectively, the spheroid-forming CSC-like cells may serve as a model system for understanding the mechanism underlying the drug resistance of CSCs and for guiding the development of better therapies that can inhibit tumor growth and eradicate CSCs.

Ischemic stroke is a focal cerebral insult that often leads to many adverse neurological complications severely affecting the quality of life. The prevalence of stroke is increasing throughout the world, while the efficacy of current pharmacological therapies remains unclear. As a neuroregenerative therapy, the implantation of human umbilical cord mesenchymal stem cells (hUC-MSCs) has shown great possibility to restore function after stroke. This review article provides an update role of hUC-MSCs implantation in the treatment of ischemic stroke. With the unique “immunosuppressive and immunoprivilege” property, hUC-MSCs are advised to be an important candidate for allogeneic cell treatment. Nevertheless, most of the treatments are still at primary stage and not clinically feasible at the current time. Several uncertain problems, such as culture conditions, allograft rejection, and potential tumorigenicity, are the choke points in this cellular therapy. More preclinical researches and clinical studies are needed before hUC-MSCs implantation can be used as a routinely applied clinical therapy.

Genetic mutations are considered to drive the development of acute myeloid leukemia (AML). With the rapid progress in sequencing technologies, many newly reported genes that are recurrently mutated in AML have been found to govern the initiation and relapse of AML. These findings suggest the need to distinguish the driver mutations, especially the most primitive single mutation, from the subsequent passenger mutations. Recent research on DNA methyltransferase 3A (DNMT3A) mutations provides the first proof-of-principle investigation on the identification of preleukemic stem cells (pre-LSCs) in AML patients. Although DNMT3A mutations alone may only transform hematopoietic stem cells into pre-LSCs without causing the full-blown leukemia, the function of this driver mutation appear to persist from AML initiation up to relapse. Therefore, identifying and targeting preleukemic mutations, such as DNMT3A mutations, in AML is a promising strategy for treatment and reduction of relapse risk.

Traumatic injuries to the nervous system lead to a common clinical problem with a quite high incidence and affect the patient’s quality of life. Based on a major challenge not yet addressed by current therapeutic interventions for these diseases, a novel promising field of neural tissue engineering has emerged, grown, and attracted increasing interest. This review provides a brief summary of the recent progress in the field, especially in combination with the research experience of the author’s group. Several important aspects related to tissue engineered nerves, including the theory on their construction, translation into the clinic, improvements in fabrication technologies, and the formation of a regenerative environment, are delineated and discussed. Furthermore, potential research directions for the future development of neural tissue engineering are suggested.

Allogeneic hematopoietic stem cell transplantation (HSCT) is one of the most effective options for hematological malignancies, and human leukocyte antigen-partially matched related donors (PMRDs) are a valuable option for HSCT. Several protocols (with or without ex vivo T-cell depletion (TCD)) have been established worldwide. TCD including CD34⁺positive selection and CD3/CD19 depletion has successfully overcome the human leukocyte antigen disparity. However, TCD is associated with prolonged immune deficiencies, increased risks of infectious complications, and high transplantation-related mortality. PMRD HSCT without ex vivo TCD is well developed, and numerous patients have benefitted from it. Here, we review the literature on PMRD HSCT.