Cells Tissues Organs最新文献

Valid and relevant models are critical for research to have biological relevance or to proceed in the right path. As well-established two-dimensional cell cultures lack niches and cues and rodent models differ in species, three-dimensional organoids emerged as a powerful platform for research. Cultured in vitro from stem cells, organoids are heterogeneous in cells and closely resemble the in vivo settings. Organoids also recapitulate the unique human features if cultured from a human source and are subjected to genetic modification. However, one type of organoid possesses only a limited selection of cells. In particular, the absence of vasculature and immune cells restricts the organoids from nutrition, cues, or critical interactions, undermining the validity of organoids as physiological or pathological models. To fill the current gap, there is an urgent need to provide organoids with vasculature and immune cells. In this paper, we review the methods to generate physiological and pathological organoid models and summarize ways to vascularize or immunize them. Our discussion continues with some advantages and disadvantages of each method and some emerging solutions to current problems.

Cancer-associated fibroblasts (CAF) in the tumor microenvironment have a decisive influence on tumor growth and metastatic behavior. The cellular origins as well as the stimuli leading to CAF formation are heterogenous, impeding a precise characterization. Aim of this study was to analyze the influence of cytokines secreted in the process of wound healing, tumor cell-associated paracrine-secreted factors, and direct cell-cell contact on the expression of the CAF-associated markers fibroblast activation protein (FAP), α-smooth muscle actin (α-SMA), thrombospondin-1 (THBS1), and tenascin-c (TNC) by RT-PCR in mesenchymal stem cells (MSC). Cells developed different morphological characteristics after incubation with wound fluid (WF). Moreover, expression of FAP and α-SMA in MSC was significantly reduced after WF compared to tumor-conditioned medium and in co-culture with tumor cells; THBS1 and TNC were not significantly altered after any of the different incubation methods. There were no alterations of expression patterns of FAP and α-SMA in the immunohistochemical analysis. Differ-ences in the cytokine composition of the media were found in the dot blot. The heterogeneity of the results emphasizes the complexity of the interactions of tumor cells and cells of the microenvironment, particularly through the addition of human-derived WF.

Many questions in human movement sciences are addressed by exploiting the advantages of animal models. However, a 3D graphical model of the musculoskeletal system of the frequently used rat model that includes a sufficient level of detail does not exist. Therefore, the aim of the present work was to develop an freely accessible 3D graphical model of the rat hindlimb. Using the anatomical data of the Wistar rat (Mus norvegicus albinus) published by Greene [1935], a 3D representation of 34 muscles of the hindlimb was drawn. Two models were created, one using muscle-like appearances and one using different colors. Each muscle can be viewed separately or within the context of its synergistic and antagonistic muscles. This model can serve to train new students before starting their experiments but also for producing illustrations of experimental conditions or results. Further development of the model will be needed to equip it with the same advanced functionalities of some of the human anatomy atlases.

The ephrin-B family of membrane-bound ligands is involved in skeletal patterning, osteogenesis, and bone homeostasis. Yet, despite the increasing collection of data affirming their importance in bone, the Eph tyrosine kinases that serve as the receptors for these ephrins in osteoblast stem cell niches remain unidentified. Here we report the expression of EphB3 at sites of bone growth in the embryo, especially at the calvaria suture fronts, periosteum, chondrocytes, and trabeculae of developing long bones. Strong EphB3 expression persisted in the adult calvarial sutures and in the proliferative chondrocytes of long bones, both of which are documented niches for osteoblastic stem cells. We observed EphB3-positive cells in the tissue filling a created calvarial injury, further implying EphB3 involvement in bone healing. Genetic knockout of EphB3 caused an increase in the bone tissue volume as a fraction of total volume in 6-week-old calvaria and in femoral trabecular density, compared to wild type controls. This difference resolved by 12 weeks of age, when we instead observed an increase in the bone volume of femoral trabeculae and in trabecular thickness. Our data identify EphB3 as a candidate regulator of osteogenesis either alone or in combination with other bone-expressed Ephs, and indicate that it appears to function as a limiter of bone growth.

There is no authoritative characterization of the attributes of the hemolymph node (HLN) since Gibbes' first description in 1884. Early reports showed that HLN are found near the kidney in human and animals with the feature of numerous erythrocytes in sinuses. Subsequent studies mainly focused on anatomy and histology, such as the source, distribution, and quantity of erythrocytes in sinuses. Recent articles mentioned that the emergence of HLN was related to immunity, but there was no strong evidence to support this hypothesis. Therefore, it is still uncertain whether the HLN is an organ of anatomy, histology, or immunology. It has been found that the development of HLN could be elicited in the parathymic area by stimuli such as Escherichia coli, allogeneic breast cancer cells, and renal tissue that were injected/transplanted into the tail of rats in our pilot studies. In this study, the model of the HLN was established by transferring allogeneic renal tissue in the rat. Intrasinusoidal erythrocytes of the node were the component for producing a red macroscopic appearance, while macrophage-erythrocyte-lymphocyte rosettes were the major immunomorphological changes, reflecting the immune activity against the invasion of the allogeneic tissue within the node. Therefore, the HLN is an immunomorphological organ.

The objective of the present study was to establish a workable approach for the production of germ cell (GC)-depleted recipient goat model using intra-testicular busulfan treatment and transplantation of cultured and enriched caprine-male GC (cmGCs) into the homologous recipients under ultrasonography (USG) guidance. The evaluation of post-transplantation colonization of donor cmGCs and restoration of the normal architecture of seminiferous tubules (ST) was performed. For this, the cmGCs of pre-pubertal male goats were isolated and enriched by differential platting for culture until the third passage. Thereafter, cells were harvested and further enriched by magnetic-activated cell sorting using rabbit-anti-CD90 antibody. After confirmation of metabolic viability (MTT-assay) and cluster-forming ability (crystal violet staining) of CD90+ cmGCs, the cells were labeled with a lipophilic red-fluorescent dye (PKH26) before transplanted into the recipient male goats by injection directly into the mediastinum testes under USG guidance. The colonization and repopulation of transplanted CD90+ cmGCs into the recipient ST was observed up to 8 weeks post-transplantation. The PKH26-labeled donor cell-derived colonies were identified in enzymatically digested ST and cryosections of recipient testes. Moreover, histochemical analyses revealed the restoration of the normal architecture of ST of recipient testis after GC transplantation. Therefore, the results suggest that the reproductive competence of infertile animals can be restored through mGC therapy and thus the methodology presented herein could be useful to obtain donor mGCs-derived functional male gametes in the recipient animal testis.

Fibrosis is the excessive deposition of extracellular matrix that results from chronic inflammation and injury, leading to the loss of tissue integrity and function. Cadherins are important adhesion molecules that classically mediate calcium-dependent cell-to-cell adhesion and play important roles in tissue development and cellular migration but likely have functions beyond these important roles. Cadherin-11 (CDH11), a member of the cadherin family, has been implicated in several pathological processes including cancer. More recent evidence suggests that CDH11 is a central mediator of tissue fibrosis. CDH11 expression is increased in patients with fibrotic diseases such as idiopathic pulmonary fibrosis and systemic sclerosis. CDH11 expression is increased in mouse models of lung, skin, liver, cardiac, renal, and intestinal fibrosis. Targeting CDH11 in murine models of fibrosis clearly demonstrates that CDH11 is a common mediator of fibrosis across multiple tissues. Insight into potential mechanisms at the cellular and molecular level is emerging. In this review, we present the evolving evidence for the involvement of CDH11 in tissue fibrosis. We also discuss some of the proposed mechanisms and highlight the potential of CDH11 as a common therapeutic target and biomarker in different fibrotic pathologies.

Periodontal ligament stem cells (PDLSCs) possess self-renewal and multilineage differentiation potential and exhibit great potential for the treatment of bone tissue defects caused by inflammation. Previous studies have indicated that static magnetic field (SMF) can enhance the proliferation and differentiation of mesenchymal stem cells (MSCs). SMF has been widely used to repair bone defects and for orthodontic and implantation treatment. In this study, we revealed that a 320 mT SMF upregulates the protein expression levels of cytokines such as MCM7 and PCNA in proliferating PDLSCs. Cell counting kit-8 results revealed that the SMF group had higher optical density values than the control group. The ratio of cells in the S phase to those in the G2/M phase was significantly increased after exposure to a 320 mT SMF. In scratch assays, the SMF-treated PDLSCs exhibited a higher migration rate than the sham-exposed group after 24 h of culture, indicating that the SMF promoted the migratory ability of PDLSCs. The activity level of the early differentiation marker alkaline phosphatase and the late marker matrix mineralization, as well as osteoblast-specific gene and protein expression, were enhanced in PDLSCs exposed to the SMF. Furthermore, AKT signaling pathway was activated by SMF. Our data demonstrated that the potential mechanism of action of SMF may enhance PDLSCs proliferation and osteogenic differentiation by activating the phosphorylated AKT pathway. The elucidation of this molecular mechanism may lead to a better understanding of bone repair responses and aid in improved stem cell-mediated regeneration.

Non-healing skin wounds remain a challenge in the healthcare system. In this sense, it is suggested that the secretome of mesenchymal stromal cells (MSCs) can be effective as a therapeutic strategy for regenerative medicine. Therefore, this systematic review aimed to determine the effects of treatment with a secretome derived from MSCs on the healing of skin wounds in a preclinical model of rodents (mice and rats). Studies were systematically retrieved from 6 databases and gray literature that provided 1,172 records, of which 25 met the inclusion criteria for qualitative analysis. Results revealed substantial heterogeneity among studies concerning experimental designs and methodologies, resulting in a high risk of bias. Together, the selected studies reported that treatment improved wound healing by (1) accelerating wound closure and improving skin repair quality; (2) reducing inflammation by decreasing the number of cells and inflammatory cytokines, accompanied by polarization of the M2 macrophage; (3) complete re-epithelialization and epidermal reorganization; (4) neovascularization promoted by proliferation of endothelial cells (CD34+) and increased levels of pro-angiogenic mediators; (5) better scar quality promoted by increased expression of collagen types I and III, as well as improved deposition and remodeling of collagen fibers. In conclusion, despite the need for alignment of methodological protocols and transparent reports in future studies, results show that the secretome of MSCs from different tissue sources corresponds to a promising tool of regenerative medicine for the treatment of skin wounds.

The present study aimed to identify the effects of sugar and methods (slow freezing [SF] vs. fast freezing [FF]) on post-thaw in vitro functional characteristics of cryopreserved caprine spermatogonial stem cells (cSSCs) and the cells obtained from cryopreserved testis tissue of prepubertal Barbari bucks. For this, in experiment 1, cSSCs were isolated and cryopreserved by either SF or FF method with different non-permeable (sugars; trehalose [140 mm; 140T or 400 mm; 400T] and sucrose [140 mm; 140S or 400 mm; 400S]) or/and permeable (5% ethylene glycol [EG] and dimethyl sulfoxide) cryoprotectants. After 1 week of cryopreservation, the cSSCs were thawed and cultured for evaluation of their characteristics. Further, in experiment 2, the effectiveness of sugars (trehalose [140 mm] or sucrose [140 mm]) for cryopreservation of testicular tissues of prepubertal Barbari bucks using the SF or FF method was evaluated. After 1 week of cryopreservation, the tissues were thawed and cSSCs were isolated and cultured for 3 weeks. In both experiments, cSSCs were evaluated for recovery rate, proliferation, metabolic viability, senescence, and stemness markers' expression. The recovery rate was 1.3-, 1.3-, and 1.1-fold higher in the 140T group compared with EG, 140S, and 400S groups, respectively. Similarly, the expression of stemness markers (protein gene product 9.5 and octamer-binding transcription factor-4) was relatively higher in 140T group compared with the other groups. In experiment 2, the recovery rate of cells per unit tissue weight was significantly (p < 0.05) higher when cryopreserved using 140 mm trehalose compared with other groups. The results of immunocytochemical analyses imply the expression of pluripotent stem cell markers in cSSCs following cryopreservation. Overall, the outcome of the study demonstrates different effects of sugars and methods on post-thaw functional properties of cSSCs with superiority of 140 mm trehalose using SF method over other treatment groups. These results are important for ex vivo expansion and differentiation of cSSCs for fertility preservation and their other downstream applications.