BACKGROUND Mesenchymal stem cells(MSCs)have great potential for the treatment of various immune diseases due to their unique immunomodulatory properties.However,MSCs exposed to the harsh inflammatory environment of da...BACKGROUND Mesenchymal stem cells(MSCs)have great potential for the treatment of various immune diseases due to their unique immunomodulatory properties.However,MSCs exposed to the harsh inflammatory environment of damaged tissue after intravenous transplantation cannot exert their biological effects,and therefore,their therapeutic efficacy is reduced.In this challenging context,an in vitro preconditioning method is necessary for the development of MSC-based therapies with increased immunomodulatory capacity and transplantation efficacy.AIM To determine whether hypoxia and inflammatory factor preconditioning increases the immunosuppressive properties of MSCs without affecting their biological characteristics.METHODS Umbilical cord MSCs(UC-MSCs)were pretreated with hypoxia(2%O_(2))exposure and inflammatory factors(interleukin-1β,tumor necrosis factor-α,interferon-γ)for 24 h.Flow cytometry,polymerase chain reaction,enzyme-linked immunosorbent assay and other experimental methods were used to evaluate the biological characteristics of pretreated UC-MSCs and to determine whether pretreatment affected the immunosuppressive ability of UC-MSCs in coculture with immune cells.RESULTS Pretreatment with hypoxia and inflammatory factors caused UC-MSCs to be elongated but did not affect their viability,proliferation or size.In addition,pretreatment significantly decreased the expression of coagulationrelated tissue factors but did not affect the expression of other surface markers.Similarly,mitochondrial function and integrity were retained.Although pretreatment promoted UC-MSC apoptosis and senescence,it increased the expression of genes and proteins related to immune regulation.Pretreatment increased peripheral blood mononuclear cell and natural killer(NK)cell proliferation rates and inhibited NK cell-induced toxicity to varying degrees.CONCLUSION In summary,hypoxia and inflammatory factor preconditioning led to higher immunosuppressive effects of MSCs without damaging their biological characteristics.展开更多
Currently, researchers are using neural stem cell transplantation to promote regeneration after peripheral nerve injury, as neural stem cells play an important role in peripheral nerve injury repair. This article revi...Currently, researchers are using neural stem cell transplantation to promote regeneration after peripheral nerve injury, as neural stem cells play an important role in peripheral nerve injury repair. This article reviews recent research progress of the role of neural stem cells in the repair of peripheral nerve injury. Neural stem cells can not only differentiate into neurons, astrocytes and oligodendrocytes, but can also differentiate into Schwann-like cells, which promote neurite outgrowth around the injury. Transplanted neural stem cells can differentiate into motor neurons that innervate muscles and promote the recovery of neurological function. To promote the repair of peripheral nerve injury, neural stem cells secrete various neurotrophic factors, including brain-derived neurotrophic factor, fibroblast growth factor, nerve growth factor, insulin-like growth factor and hepatocyte growth factor. In addition, neural stem cells also promote regeneration of the axonal myelin sheath, angiogenesis, and immune regulation. It can be concluded that neural stem cells promote the repair of peripheral nerve injury through a variety of ways.展开更多
AIM: To demonstrate the relationship between H-ras oncogene and hepatocellular carcinoma (HCC) metastasis. METHODS: Activated H-ras oncogene was transfected into SMMC 7721, a cell line derived from human HCC, by calci...AIM: To demonstrate the relationship between H-ras oncogene and hepatocellular carcinoma (HCC) metastasis. METHODS: Activated H-ras oncogene was transfected into SMMC 7721, a cell line derived from human HCC, by calcium phosphate transfection method. Some metastasis-related parameters were detected in vitro, including adhesion assay, migration assay, expression of collagenase IV(c IV ase) and epidermal growth factor receptor (EGFR). RESULTS: The abilities of H-ras-transfected cell clones in adhesion to laminin (LN) or fibronectin (FN), migration, c IV ase secretion increased markedly, and the expression of EGFR elevated moderately. More importantly, these alterations were consistent positively with the expression of p21, the protein product of H-ras oncogene. CONCLUSION: H-ras oncogene could induce the metastatic phenotype of HCC cell in vitro to raise its metastatic potential.展开更多
AIM To compare the capacity of newly developed epidermal growth factor receptor(EGFR)-targeted immune magnetic liposomes(EILs) vs epithelial cell adhesion molecule(Ep CAM) immunomagnetic beads to capture colorectal ci...AIM To compare the capacity of newly developed epidermal growth factor receptor(EGFR)-targeted immune magnetic liposomes(EILs) vs epithelial cell adhesion molecule(Ep CAM) immunomagnetic beads to capture colorectal circulating tumor cells(CTCs).METHODS EILs were prepared using a two-step method, and the magnetic and surface characteristics were confirmed. The efficiency of capturing colorectal CTCs as well as the specificity were compared between EILs and Ep CAM magnetic beads. RESULTS The obtained EILs had a lipid nanoparticle structure similar to cell membrane. Improved binding with cancer cells was seen in EILs compared with the method of coupling nano/microspheres with antibody. The binding increased as the contact time extended. Compared with Ep CAM immunomagnetic beads, EILs captured more CTCs in peripheral blood from colorectal cancer patients. The captured cells showed consistency with clinical diagnosis and pathology. Mutation analysis showed same results between captured CTCs and cancer tissues. CONCLUSION EGFR antibody-coated magnetic liposomes show high efficiency and specificity in capturing colorectal CTCs.展开更多
Immune evasion is a strategy used by pathogenic microbes to evade the host immune system in order to ensure successful propagation. Immune evasion is particularly important for the blood stages of Plasmodium falciparu...Immune evasion is a strategy used by pathogenic microbes to evade the host immune system in order to ensure successful propagation. Immune evasion is particularly important for the blood stages of Plasmodium falciparum, the causative agent of the deadly disease malaria tropica. Because Plasmodium blood stage parasites require human erythrocytes for replication, their ability to evade attack by the human immune system is essential for parasite survival. In order to escape immunity-induced killing, the intraerythrocytic parasites have evolved a variety of evasion mechanisms, including expansion of plasmodial surface proteins, organ-specific sequestration of the infected red blood cells and acquisition of immune-regulatory proteins by the parasite. This review aims to highlight recent advances in the molecular understanding of the immune evasion strategies by P. falciparum, including antigenic variation, surface protein polymorphisms and invasion ligand diversification. The review will further discuss new findings on the regulatory mechanisms applied by P. falciparum to avoid lysis by the human complement as well as killing by immune factors of the mosquito vector.展开更多
Mesenchymal stem cells(MSCs),multipotent stromal cells,have attracted exten-sive attention in the field of regenerative medicine and cell therapy due to the capacity of self-renewal,multilineage differentiation,and im...Mesenchymal stem cells(MSCs),multipotent stromal cells,have attracted exten-sive attention in the field of regenerative medicine and cell therapy due to the capacity of self-renewal,multilineage differentiation,and immune regulation.MSCs have different cellular effects in different diseases,and even have markedly different curative effects with different tissue sources,indicating the plasticity of MSCs.The phenotypes,secreted factors,and proliferative,migratory,differentiating,and immunomodulatory effects of MSCs depend on certain mediators present in their microenvironment.Understanding microenvironmental factors and their internal mechanisms in MSC responses may help in subsequent prediction and improvement of clinical benefits.This review highlighted the recent advances in MSC plas-ticity in the physiological and pathological microenvironment and multiple microenviron-mental factors regulating MSC plasticity.It also highlighted some progress in the underlying molecular mechanisms of MSC remodeling in the microenvironment.It might provide refer-ences for the improvement in vitro culture of MSCs,clinical application,and in vivo induction.Copyrightª2020,Chongqing Medical University.Production and hosting by Elsevier B.V.This is an open access article under the CC BY-NC-ND license(http://creativecommons.org/licenses/by-nc-nd/4.0/).展开更多
基金This study was approved by the Medical Ethics Committee of Shanxi Medical University(Approval No.2018LL016).
文摘BACKGROUND Mesenchymal stem cells(MSCs)have great potential for the treatment of various immune diseases due to their unique immunomodulatory properties.However,MSCs exposed to the harsh inflammatory environment of damaged tissue after intravenous transplantation cannot exert their biological effects,and therefore,their therapeutic efficacy is reduced.In this challenging context,an in vitro preconditioning method is necessary for the development of MSC-based therapies with increased immunomodulatory capacity and transplantation efficacy.AIM To determine whether hypoxia and inflammatory factor preconditioning increases the immunosuppressive properties of MSCs without affecting their biological characteristics.METHODS Umbilical cord MSCs(UC-MSCs)were pretreated with hypoxia(2%O_(2))exposure and inflammatory factors(interleukin-1β,tumor necrosis factor-α,interferon-γ)for 24 h.Flow cytometry,polymerase chain reaction,enzyme-linked immunosorbent assay and other experimental methods were used to evaluate the biological characteristics of pretreated UC-MSCs and to determine whether pretreatment affected the immunosuppressive ability of UC-MSCs in coculture with immune cells.RESULTS Pretreatment with hypoxia and inflammatory factors caused UC-MSCs to be elongated but did not affect their viability,proliferation or size.In addition,pretreatment significantly decreased the expression of coagulationrelated tissue factors but did not affect the expression of other surface markers.Similarly,mitochondrial function and integrity were retained.Although pretreatment promoted UC-MSC apoptosis and senescence,it increased the expression of genes and proteins related to immune regulation.Pretreatment increased peripheral blood mononuclear cell and natural killer(NK)cell proliferation rates and inhibited NK cell-induced toxicity to varying degrees.CONCLUSION In summary,hypoxia and inflammatory factor preconditioning led to higher immunosuppressive effects of MSCs without damaging their biological characteristics.
基金supported by the Major State Basic Research and Development Program of China(973 Program),No.2014CB542201the National Key Research and Development Program of China,No.2016YFC1101601,2017YFA0104702+2 种基金the Natural Science Foundation of Beijing of China,No.7172202a grant from the 13th Five-Year Plan Period of People’s Liberation Army of China,No.BWS13C029-5a grant from the Science and Technology Project of Beijing of China,No.Z161100005016059
文摘Currently, researchers are using neural stem cell transplantation to promote regeneration after peripheral nerve injury, as neural stem cells play an important role in peripheral nerve injury repair. This article reviews recent research progress of the role of neural stem cells in the repair of peripheral nerve injury. Neural stem cells can not only differentiate into neurons, astrocytes and oligodendrocytes, but can also differentiate into Schwann-like cells, which promote neurite outgrowth around the injury. Transplanted neural stem cells can differentiate into motor neurons that innervate muscles and promote the recovery of neurological function. To promote the repair of peripheral nerve injury, neural stem cells secrete various neurotrophic factors, including brain-derived neurotrophic factor, fibroblast growth factor, nerve growth factor, insulin-like growth factor and hepatocyte growth factor. In addition, neural stem cells also promote regeneration of the axonal myelin sheath, angiogenesis, and immune regulation. It can be concluded that neural stem cells promote the repair of peripheral nerve injury through a variety of ways.
文摘AIM: To demonstrate the relationship between H-ras oncogene and hepatocellular carcinoma (HCC) metastasis. METHODS: Activated H-ras oncogene was transfected into SMMC 7721, a cell line derived from human HCC, by calcium phosphate transfection method. Some metastasis-related parameters were detected in vitro, including adhesion assay, migration assay, expression of collagenase IV(c IV ase) and epidermal growth factor receptor (EGFR). RESULTS: The abilities of H-ras-transfected cell clones in adhesion to laminin (LN) or fibronectin (FN), migration, c IV ase secretion increased markedly, and the expression of EGFR elevated moderately. More importantly, these alterations were consistent positively with the expression of p21, the protein product of H-ras oncogene. CONCLUSION: H-ras oncogene could induce the metastatic phenotype of HCC cell in vitro to raise its metastatic potential.
文摘AIM To compare the capacity of newly developed epidermal growth factor receptor(EGFR)-targeted immune magnetic liposomes(EILs) vs epithelial cell adhesion molecule(Ep CAM) immunomagnetic beads to capture colorectal circulating tumor cells(CTCs).METHODS EILs were prepared using a two-step method, and the magnetic and surface characteristics were confirmed. The efficiency of capturing colorectal CTCs as well as the specificity were compared between EILs and Ep CAM magnetic beads. RESULTS The obtained EILs had a lipid nanoparticle structure similar to cell membrane. Improved binding with cancer cells was seen in EILs compared with the method of coupling nano/microspheres with antibody. The binding increased as the contact time extended. Compared with Ep CAM immunomagnetic beads, EILs captured more CTCs in peripheral blood from colorectal cancer patients. The captured cells showed consistency with clinical diagnosis and pathology. Mutation analysis showed same results between captured CTCs and cancer tissues. CONCLUSION EGFR antibody-coated magnetic liposomes show high efficiency and specificity in capturing colorectal CTCs.
文摘Immune evasion is a strategy used by pathogenic microbes to evade the host immune system in order to ensure successful propagation. Immune evasion is particularly important for the blood stages of Plasmodium falciparum, the causative agent of the deadly disease malaria tropica. Because Plasmodium blood stage parasites require human erythrocytes for replication, their ability to evade attack by the human immune system is essential for parasite survival. In order to escape immunity-induced killing, the intraerythrocytic parasites have evolved a variety of evasion mechanisms, including expansion of plasmodial surface proteins, organ-specific sequestration of the infected red blood cells and acquisition of immune-regulatory proteins by the parasite. This review aims to highlight recent advances in the molecular understanding of the immune evasion strategies by P. falciparum, including antigenic variation, surface protein polymorphisms and invasion ligand diversification. The review will further discuss new findings on the regulatory mechanisms applied by P. falciparum to avoid lysis by the human complement as well as killing by immune factors of the mosquito vector.
基金This work was supported by grant from Provincial Key Research and Development of Jiangsu Province(No.BE2019706)。
文摘Mesenchymal stem cells(MSCs),multipotent stromal cells,have attracted exten-sive attention in the field of regenerative medicine and cell therapy due to the capacity of self-renewal,multilineage differentiation,and immune regulation.MSCs have different cellular effects in different diseases,and even have markedly different curative effects with different tissue sources,indicating the plasticity of MSCs.The phenotypes,secreted factors,and proliferative,migratory,differentiating,and immunomodulatory effects of MSCs depend on certain mediators present in their microenvironment.Understanding microenvironmental factors and their internal mechanisms in MSC responses may help in subsequent prediction and improvement of clinical benefits.This review highlighted the recent advances in MSC plas-ticity in the physiological and pathological microenvironment and multiple microenviron-mental factors regulating MSC plasticity.It also highlighted some progress in the underlying molecular mechanisms of MSC remodeling in the microenvironment.It might provide refer-ences for the improvement in vitro culture of MSCs,clinical application,and in vivo induction.Copyrightª2020,Chongqing Medical University.Production and hosting by Elsevier B.V.This is an open access article under the CC BY-NC-ND license(http://creativecommons.org/licenses/by-nc-nd/4.0/).