Revolutionizing tumor immunotherapy:unleashing the power of progenitor exhausted T cells

In exploring persistent infections and malignancies, a distinctive subgroup of CD8^(+) T cells, progenitor exhausted CD8^(+) T(Tpex) cells, has been identified. These Tpex cells are notable for their remarkable self-renewal and rapid proliferation abilities. Recent strides in immunotherapy have demonstrated that Tpex cells expand and differentiate into responsive exhausted CD8^(+) T cells, thus underscoring their critical role in the immunotherapeutic retort. Clinical examinations have further clarified a robust positive correlation between the proportional abundance of Tpex cells and enhanced clinical prognosis. Tpex cells have found noteworthy applications in the formulation of inventive immunotherapeutic approaches against tumors. This review describes the functions of Tpex cells in the tumor milieu, particularly their potential utility in tumor immunotherapy. Precisely directing Tpex cells may be essential to achieving successful outcomes in immunotherapy against tumors.

CD133:A cancer stem cells marker, is used in colorectal cancers

Colorectal cancer is one of the most common malignant tumors worldwide. A model of cancer development involving cancer stem cells has been put forward because it provides a possible explanation of tumor hierarchy. Cancer stem cells are characterized by their proliferation, tumorigenesis, differentiation, and selfrenewal capacities, and chemoradiotherapy resistance. Due to the role of cancer stem cells in tumor initiation and treatment failure, studies of cancer stem cell markers, such as CD133, have been of great interest. CD133, a five-transmembrane glycoprotein, is widely used as a marker to identify and isolate colorectal cancer stem cells. This marker has been investigated to better understand the characteristics and functions of cancer stem cells. Moreover, it can also be used to predict tumor progression, patient survival, chemoradiotherapy resistance and other clinical parameters. In this review, we discuss the use of CD133 in the identification of colorectal cancer stem cell, which is currently controversial. Although the function of CD133 is as yet unclear, we have discussed several possible functions and associated mechanisms that may partially explain the role of CD133 in colorectal cancers. In addition, we focus on the prognostic value of CD133 in colorectal cancers. Finally, we predict that CD133 may be used as a possible target for colorectal cancer treatment.

Autologous CD34^+ and CD133^+ stem cells transplantation in patients with end stage liver disease

AIM:To assess the utility of an autologous CD34 + and CD133 + stem cells infusion as a possible therapeutic modality in patients with end-stage liver diseases.METHODS:One hundred and forty patients with endstage liver diseases were randomized into two groups.Group 1,comprising 90 patients,received granulocyte colony stimulating factor for five days followed by autologous CD34 + and CD133 + stem cell infusion in the portal vein.Group 2,comprising 50 patients,received regular liver treatment only and served as a control group.RESULTS:Near normalization of liver enzymes and improvement in synthetic function were observed in 54.5% of the group 1 patients;13.6% of the patients showed stable states in the infused group.None of the patients in the control group showed improvement.No adverse effects were noted.CONCLUSION:Our data showed that a CD34 + and CD133 + stem cells infusion can be used as supportive treatment for end-stage liver disease with satisfactory tolerability.

CD133^+ gallbladder carcinoma cells exhibit self-renewal ability and tumorigenicity

AIM： To identify cancer stern cells （CSCs） in human gallbladder carcinomas （GBCs）. METHODS： Primary GBC cells were cultured under serum-free conditions to produce floating spheres. The stem-cell properties of the sphere-forming cells, including self-renewal, differentiation potential, chemoresistance and tumorigenicity, were determined in vitro or in vivo. Cell surface expression of CD133 was investigated in primary tumors and in spheroid cells using flow cytometry. The sphere-colony-formation ability and tumorigenicity of CD133＋ cells were assayed.floating spheroids were generated from primary GBC cells, and these sphere-forming cells could generate new progeny spheroids in serum-free media. Spheroid cells were differentiated under serum-containing conditions with downregulation of the stem cell markers Oct-4, Nanog, and nestin （P 〈 0.05）. The differentiated cells showed lower spheroid-colony-formation ability than the original spheroid cells （P 〈 0.05）. Spheroid ceils were more resistant to chemotherapeutic reagents than the congenetic adherent cells （P 〈 0.05）. Flow cytometry showed enriched CD133＋ population in sphereforming cells （P 〈 0.05）. CD133＋ cells possessed high colony-formation ability than the CD133 population （P 〈 0.01）. CD133＋ cells injected into nude mice revealed higher tumorigenicity than their antigen-negative counterparts （P 〈 0.05）. CONCLUSION： CD133 may be a cell surface marker for CSCs in GBC.

Upregulated CD133 expression in tumorigenesis of colon cancer cells

AIM: To analyze the upregulated CD133 expression in tumorigenesis of primary colon cancer cells. METHODS: Upregulated CD133 expression in tumorigenesis of colorectal cancer cell lines (Lovo, Colo205, Caco-2, HCT116 and SW620) was analyzed by flow cytometry. Human colon cancer tissue samples were stained with anti-human CD133. SW620 cells were sorted according to the CD133 expression level measured by fluorescence-activated cell sorting. Spheroids of colorectal cancer cells were cultured with the hanging drop. Expression of CD133 and Lgr5 in spheroids of colorectal cancer cells and monolayer culture was detected by RT-qPCR. Spheroids of colorectal cancer cells were analyzed using anti-human CD133 with immunohistochemical staining. RESULTS: CD133 antigen was expressed in colorectal cancer cell lines (Lovo, Colo205, Caco-2, HCT116 and SW620) as well as in primary and metastatic human colon cancer tissues. However, the CD133 was differently expressed in these cell lines and tissues. The expression levels of CD133 and Lgr5 were significantly higher in spheroids of parental, CD133hi and CD133-cells than in their monolayer culture at the mRNA level (P < 0.05). Immunohistochemical staining of spheroids of CD133-cells showed that CD133 was highly expressed in colorectal cancer cell lines. CONCLUSION: Upregulated CD133 expression plays a role in tumorigenesis colorectal cancer cells, which may promote the expression of other critical genes that can drive tumorigenesis.

HUMAN PRIMITIVE HEMATOPOIETIC PROGENITOR CELLS ARE MORE ENRICHED IN CD34^+CD38^- POPULATION THAN IN CD34^+CD38^+ POPULATION

To clarify the hematopoietic potential of various sub-classes of human hematopoietic progenitor cells, we used a multicolor staining protocol in conjunction with anti-CD34 and -CD38 McAb. We characterized two cell fractions in CD34+cells with or without CD38 expression. A clonogenic assay showed that most CFC were present in CD34+CD38+ population. Morphologic analysis showed that blast-like cells were more enriched in the CD34+CD38 fraction. To clarify the biologic differences between both fractions, we examined the more primitive progenitor cell function by assessing long-term culture-initiating cells (LTC-IC) on the stromal cells. At the first two weeks, more CF.C harvested from the culture in the fractions initiated with both populations. However, more LTC-IC were present during weeks 4 to 12 in the CD34+CD38- population. These results indicate the primitive progenitors are more enriched in CD34+CD38 population than in CD34+CD38+ cells.

Inhibitive effect of IL-24 gene on CD133^+ laryngeal cancer cells

Objective:To explore the inhihitive and apoptosis inductive effect of IL-24 genes on CD133^+laryngeal cancer cells in Hep-2 line.Methods:Human peripheral blood monocytes were isolated.The total RNA was extracted by using Trizol method and reverse transcripted into cDNA using RT-PCR method.Primers P1 and P2 was designed for the amplification of human IL-24 genes.After confirmation of agarose gel electrophoresis tests,TA was cloned into pMD19-T simple vector.Nhe Ⅰ and Xho Ⅰ double digesting human IL-24 and pIRES2-ZsGreen1 and eukaryotic expression vector were used to establish the pIRES2-ZsGreen1-hIL-24 vector,and detected by enzyme digestion and gene sequencing methods.Flow cytometry(FCM) was used to isolate CD133^+ cells from Hep-2 cells.CD133^+ cells were transfected with pIRES2-ZsGreen1-hIL-24 through liposome 2000.After detection,MTT and FCM were used to observe the effect of IL-24 gene on CD133^+ laryngeal cancer Hep-2 cells.Results:Lipotin mediated transfection of recombinant pIRES2-ZsGreen1-hIL-24 plasmid into CD133^+ Hep-2 could expressed IL-24 gene in cells stably.MTT results showed that IL-24 transfected group was significantly suppressed compared to empty vector group and control group(P<0.05);FCM results showed that the apoptosis rate of experimental group increased significantly compared to empty vector group and control group(P<0.05).Conclusions:IL-24 gene expressions can inhibit proliferation of CD133^+laryngeal cells in Hep-2 line and promote their apoptosis.

Cisplatin selects for CD133+cells in lung cancer cells

Objective Platinum-based chemotherapy is the first-line treatment for non-small cell lung cancer,but the chemoresistance of tumor cells continues to be a considerable challenge in the management of NSCLCs,leading to recurrence of most patients.CD133(prominin-1)is a five-transmembrane glycoprotein,and recent evidence suggests that CD133+cells are the cause of drug resistance and tumor recurrence.In this study,the correlation between cisplatin and CD133+cells was investigated systematically.Methods Four lung cancer cell lines,including A549,H460,801D and H1299,were treated with different concentrations of cisplatin.Cell viability was determined by MTT assay.Sphere-forming assay was performed to detect the capability of sphere-forming.CD133+cells was detected by BD FACScaliber flow cytometer.Results The results showed that cisplatin could increase the number of CD133+cells in both time-and dose-dependent manner.The enrichment would weaken but the proportion of CD133+cells was still higher than the basic level as incubation time extended after cisplatin was withdrawn.Compared with adherent culture,the proportion of CD133+cells was higher when the cells were maintained suspension culture.The proportion of CD133+cells significantly increased when cisplatin was provided in suspension culture.Conclusion These results revealed that cisplatin induces the enrichment of CD133+cells and CD133 is a new therapeutic target.Our data partially explained drug resistance to second-line chemotherapy in cisplatin-treated patients with NSCLCs.

The Cross-talk between ROS and p38MAPKα in the Ex Vivo Expanded Human Umbilical Cord Blood CD133^+ Cells

This study investigated the correlation between and compared the effects of reactive oxygen species（ROS） and p38 mitogen-activated protein kinase α（p38MAPKα） in the ex vivo expanded umbilical cord blood（hUCB） CD133＋ cells.hUCB CD133＋ cells were cultured in the hematopoietic stem cells（HSCs） culture medium with N-acetylcysteine（NAC,an anti-oxidant）,p38MAPKα-specific inhibitor（SB203580） or their combination.The levels of ROS and expression of phosphorylated p38MAPKα（p-p38） in CD133＋ cells were flow cytometrically detected.The efficacy of ex vivo expansion was evaluated by the density of CD133＋ cell sub-group colony-forming cells（CFC） and cobblestone area-forming cells（CAFC） assay.Our results showed decreased ROS levels in NAC,SB203580,and their combination treatment groups were almost 37%,48%,and 85%,respectively.Furthermore,SB203580 abrogated the activation of p38MAPKα more obviously than NAC.Moreover,the CD133＋ cells in SB203580 treatment group had a 21.93±1.36-fold increase,and 14.50±1.19-fold increase in NAC treatment group,but only 10.13±0.57-fold increase in control group.In addition,SB203580 treatment led a higher level increase in the number of CFU and CAFC than NAC did.These findings suggested that,in expanded CD133＋ cells,ROS activates p38MAPKα,which,in turn,induces ROS production,and p38MAPKα might be the most suitable regulator in ROS-p38MAPKα pathway for the promotion of HSCs ex vivo expansion.

Influence of CD133^+ expression on patients' survival and resistance of CD133^+ cells to anti-tumor reagents in gastric cancer

Objective:To investigate the influence of CD133+expression on patients'survival and resistance of CD133+cells to anti-tumor agents in gastric cancer(GC).Methods:Influence of CD133 expression on prognosis was analyzed employing samples from patients with GC.GC cell lines were utilized to separate CD133+and CD133-subpopulations by immunomagnetic separation and to analyze the biological features of two subpopulations in vitro and in vivo,especially in resistant to anti-tumor reagents and its apoptotic mechanism.Results:The lower CD133+group showed a significantly better survival compared with the higher CD133+group.The highest content of CD133+subpopulations for KATO-III cells had stronger proliferative ability than CD133-subpopulations.A single CD133+cell was capable of generating new cell colony and the tumorigenicity rate in nude mice was100%for CD133+clonal spheres or for CD133+cells,but 0%for CD133-cells.Furthermore,the higher expression levels of Oct-4,Sox-2,Musashi-1 and ABCG2 in CD133+clonal spheres were identified compared with CD133+cells or CD133-cells.Under the treatment of anti-tumor reagents,CD133+cells had lower suppression rates compared with CD133-cells while lower level of Bcl-2 and higher level of Bax were found in CD133+cells compared with CD133-cells.Conclusions:The patients with lower CD133+expression had a better survival.Enriched CD133+cells in clonal sphere shared the ability to be self-renewable,proliferative,tumorigenic and resistant to anti-tumor agents as probably regulated by Bcl-2 and Bax.

Influence on Biological Behavior of Colon Cancer Stem Cells after RNA Interfering CD133

OBJECTIVE To observe the effects expression and activation on biological cancer stem cells. of blocking CD133 gene characteristic of the colon METHODS CD133＋ colon cancer stem cells （CCSCs） were separated from EpCAMhigh CD44＋ CCSCs through fluorescenceactivated cell sorting （FACS）. The proliferation, the capability of spherical cell formation, neoplasia, and the expression of ABCG2 mRNA of CD133＋ CCSCs were observed after the CD133＋ CCSCs were infected with LV-CD133shRNA. CD133 negative cells were isolated from EpCAMhigh CD44＋ CCSCs with FACS, and the CD133 proteins in CD133- cells were detected with Western blot. RESULTS CD133＋ CCSCs were isolated from EpCAMhigh CD44＋ CCSCs using FACS, and they accounted for 89.2% in the stem cells. In the experimental group, after the CD133＋ CCSCs were knocked down by LV-CD133shRNA RNAi, the growth pattern of the cells in the stem cell culture changed into adherent growth from suspended growth, and couldn＇t generate spherical cells. Results of MTT assay showed that the CD133＋ CCSCs infected with LV-CD133shRNA grew slowly, compared to the cells in the control groups. There was a decrease in the cloning efficiency. The infected cells were transplanted into the BALB/c nude mice. During the observation, no neoplasia was found in the CD133＋ cells infected with LV-CD133shRNA. The level of ABCG2 mRNA expression was lowered greatly （P 〈 0.01）. CD133- cells were obtained from the EpCAMhigh CD44＋ CCSCs using FACS, in which the expression of CD133 protein was positive. CONCLUSION CD133 retains the biological characteristics of the colon cancer stem cells.

A familiar stranger:CD34 expression and putative functions in SVF cells of adipose tissue

Human adipose tissue obtained by liposuction is easily accessible and an abundant potential source of autologous cells for regenerative medicine applications. After digestion of the tissue and removal of differentiated adipocytes, the so-called stromal vascular fraction (SVF) of adipose, a mix of various cell types, is obtained. SVF contains mesenchymal fibroblastic cells, able to adhere to culture plastic and to generate large colonies in vitro , that closely resemble bone marrow-derived colony forming units-fibroblastic, and whose expanded progeny, adipose mesenchymal stem/stromal cells (ASC), show strong similarities with bone marrow mesenchymal stem cells. The sialomucin CD34, which is well known as a hematopoietic stem cell marker, is also expressed by ASC in native adipose tissue but its expression is gradually lost upon standard ASC expansion in vitro . Surprisingly little is known about the functional role of CD34 in the biology and tissue forming capacity of SVF cells and ASC. The present editorial provides a short introduction to the CD34 family of sialomucins and reviews the data from the literature concerning ex- pression and function of these proteins in SVF cells and their in vitro expanded progeny.

Mobilization of hematopoietic progenitor cells in patients with liver cirrhosis

AIM:To test the hypothesis that liver cirrhosis is associated with mobilization of hematopoietic progenitor cells. METHODS:Peripheral blood samples from 72 patients with liver cirrhosis of varying etiology were analyzed by flow cytometry.Identified progenitor cell subsets were immunoselected and used for functional assays in vitro. Plasma levels of stromal cell-derived factor-1(SDF-1) were measured using an enzyme linked immunosorbent assay.RESULTS:Progenitor cells with a CD133 + /CD45 + CD14 + phenotype were observed in 61%of th patients.Between 1%and 26%of the peripheral bloo mononuclear cells(MNCs)displayed this phenotype Furthermore,a distinct population of c-kit + progenito cells(between 1%and 38%of the MNCs)could b detected in 91%of the patients.Additionally,18% of the patients showed a population of progenito cells(between 1%and 68%of the MNCs)that wa characterized by expression of breast cancer resistanc protein-1.Further phenotypic analysis disclosed tha the circulating precursors expressed CXC chemokin receptor 4,the receptor for SDF-1.In line with thi finding,elevated plasma levels of SDF-1 were presen in all patients and were found to correlate with th number of mobilized CD133 + progenitor cells.

Hematopoietic stem cells in research and clinical applications:The“CD34 issue”

In this paper,experimental findings concerning the kinetics of hematopoietic reconstitution are compared to corresponding clinical data.Although not clearly apparent,the transplantation practice seems to confirm the basic proposals of experimental hematology concerning hematopoietic reconstitution resulting from successive waves of repopulation stemming from different subpopulations of progenitor and stem cells.One of the "f irst rate" parameters in clinical transplantations in hematology;i.e.the CD34+ positive cell dose,has been discussed with respect to the functional heterogeneity and variability of cell populations endowed by expression of CD34.This parameter is useful only if the relative proportion of stem and progenitor cells in the CD34+ cell population is more or less maintained in a series of patients or donors.This proportion could vary with respect to the source,pathology,treatment,processing procedure,the graft ex vivo treatment and so on.Therefore,a universal dose of CD34+ cells cannot be def ined.In addition,to avoid further confusion,the CD34+ cells should not be named "stem cells" or "progenitor cells" since these denominations only concern functionally characterized cell entities.

Angioarchitecture and CD133^+ tumor stem cell distribution in intracranial hemangiopericytoma A comparative study with meningioma

Angioarchitecture plays an important role in the malignant development of intracranial hemangiopericytoma. It remains poorly understood whether high frequency of hemorrhage during clinical surgery for intracranial hemangiopericytoma is associated with angioarchitecture. The present study utilized hematoxylin-eosin staining, and immunohistochemical staining with epithelial membrane antigen, vimentin, CD34, von Willebrand factor （vWF） and CD133 to observe characteristics of angioarchitecture. In addition, silver stains were used to demonstrate changes in reticular fibers in the wall of vessel channels in intracranial hemangiopericytoma and meningioma. Five patterns of angioarchitecture were identified in intracranial hemangiopericytoma, namely tumor cell islands, vasculogenic mimicry, mosaic blood vessels, sprouting angiogenesis, and intussusceptive angiogenesis. Several CD133＋ tumor cells were found to form tumor cell islands. A connection between vWF ^＋ and vWF channels was detected in the pattern of intussusceptive angiogenesis, and some vimentin^＋ tumor cells were embedded in the periodic acid-Schiff positive channel wall. Incomplete threads of reticular fibers formed the walls of larger pseudo-vascular channels and some tumor clumps or scattered tumor cells were detected ＂floating＂ in them. The angioarchitecture, specific markers and reticular fibers of intracranial hemangiopericytoma were significantly different from meningioma. Angioarchitecture provides a functional vascular network for vascular evolution in intracranial hemangiopericytoma and contributes to significant intra-operative bleeding.

Impact of T cells on hematopoietic stem and progenitor cell function:Good guys or bad guys?

When hematopoietic stem and progenitor cells(HSPC)are harvested for transplantation, either from the bone marrow or from mobilized blood, the graft contains a significant number of T cells. It is these T cells that are the major drivers of graft-vs-host disease(Gv HD). The risk for Gv HD can simply be reduced by the removal of these T cells from the graft. However, this is not always desirable, as this procedure also decreases the engraftment of the transplanted HSPCs and, if applicable, a graft-vs-tumor effect. This poses an important conundrum in the field: T cells act as a double-edged sword upon allogeneic HSPC transplantation, as they support engraftment of HSPCs and provide anti-tumor activity, but can also cause Gv HD. It has recently been suggested that T cells also enhance the engraftment of autologous HSPCs, thus supporting the notion that T cells and HSPCs have an important functional interaction that is highly beneficial, in particular during transplantation. The underlying reason on why and how T cells contribute to HSPC engraftment is still poorly understood. Therefore, we evaluate in this review the studies that have examined the role of T cells during HSPC transplantation and the possible mechanisms involved in their supporting function. Understanding the underlying cellular and molecular mechanisms can provide new insight into improving HSPC engraftment and thus lower the number of HSPCs required during transplantation. Moreover, it could provide new avenues to limit the development of severe Gv HD, thus making HSPC transplantations more efficient and ultimately safer.

Apoptotic bone marrow CD34+ cells in cirrhotic patients

AIM: To access the frequency and level of apoptotic CD34+ cells isolated from the marrow fluid of patients with post-hepatitis cirrhosis. METHODS: The frequency of bone marrow CD34+ cells and apoptotic bone marrow CD34+ cells in 31 inpatients with post-hepatitis cirrhosis (cirrhosis group), and 15 out-patients without liver or blood disorders (control group) was calculated by flow cytometry. Parameters were collected to evaluate liver functions of patients in cirrhosis group. RESULTS: The percentage of normal bone marrow CD34+ cells was 6.30% ± 2.48% and 1.87% ± 0.53% (t = 3.906, P < 0.01) while that of apoptotic marrowCD34+ cells was 15.00% ± 15.81% and 5.73% ± 1.57% (t = 2.367, P < 0.05) in cirrhosis and control groups, respectively. The percentage of apoptotic marrow CD34+ cells was 6.25% ± 3.30% and 20.92 ± 18.5% (t = 2.409, P < 0.05) in Child-Pugh A and Child-Pugh B + C cirrhotic patients, respectively. The percentage of late apoptotic marrow CD34+ cells was positively correlated with the total bilirubin and aspartate aminotransferase serum levels in patients with cirrhosis. CONCLUSION: The status of CD34+ marrow cells in cirrhotic patients may suggest that the ability of hematopoietic progenitor cells to transform into mature blood cells is impaired.

Characteristics of Ex Vivo Expansion of Endothelial Progenitor Cells

Summary： The characteristics for the ex vivo expansion of the endothelial progenitor cells （EPCs） were explored, CD34^＋ cells were selected from umbilical cord blood mononuclear cells （MNC） by MiniMACS system, expanded under the same conditions as those for total MNC, coincubation of CD34^＋ and CD34 from the same donor for EPCs. In addition, the effects of vessel endothelial growth factor （VEGF） and passage on cell differentiation, expansion kinetics and apoptosis were examined, EPCs were determined and quantified by immunocytochemistry and flow cytometry, The results showed that both coculture of CD346＋ and CD34^- and total MNC led to a significant increase in the expansion of CD34^＋ cells as compared with CD34 enrichment （P〈0.05）. There was a tendency toward decreased apoptosis in cultures when early passage was performed immediately after cord like structures appeared. VEGF had no significant effect on apoptosis （P〉0.05）, These differentiated EPCs were positive for CD34^＋, von Willebrand factor （vWF）, KDR, CD31 staining and phagocytized acetylated low-density lipoprotein （LDL）. CD34^＋ cells accounted for （68.2±6,3） % of attaching （AT） cells at day 7 of culture. It was suggested the most efficient method to ex vivo expansion of EPCs was coculture of CD34^＋ and CD34^- or total MNC. Early passage makes cell apoptosis rate decrease. VEGF had no significant effect on ex vivo expansion of EPCs.

Proliferation Characteristics of CD133+ Cell Population in Colorectal Cancer

In this study,CD133+ subpopulations were isolated from 41 primary colorectal cancer tissues,the proliferation and cell cycle distribution of the cells were examined without in vitro expansion,and then compared to those of cell lines.The detection of CD133 in colorectal cancer tissues,isolation of CD133+ and CD133-epithelial subpopulations,Ki-67/DNA multiparameter assay and cell volume analysis were flow cytometrically conducted.The results showed that Ki-67 expression was correlated with CD133 level in primary cancer tissues,while cell cycle G 2 /M phase distribution or clinicopathological characteristics was not.In addition,the CD133+ cells showed larger cell volume and higher Ki-67 expression as compared with CD133-cells.But there was no statistically significant difference in G 2 /M phase distribution between the two subpopulations.Our results demonstrated that the CD133+ subpopulation in colorectal cancer tissue contained more actively cycling and proliferating cells,which was not correlated to clinicopathological factors but might contribute to tumor progression and poor clinical outcome.