Very small embryonic-like stem cells purified from umbilical cord blood lack stem cell characteristics
ABSTRACT: Very small embryonic-like (VSEL) cells have been described as putatively pluripotent stem cells present in murine bone marrow and human umbilical cord blood (hUCB) and as such are of high potential interest for regenerative medicine. However, there remain some questions concerning the precise identity and properties of VSEL cells, particularly those derived from hUCB. For this reason, we have carried out an extensive characterisation of purified populations of VSEL cells from a large number of UCB samples. Consistent with a previous report, we find that VSEL cells are CXCR4+, have a high density, are indeed significantly smaller than HSC and have an extremely high nuclear/cytoplasmic ratio. Their nucleoplasm is unstructured and stains strongly with Hoechst 33342. A comprehensive FACS screen for surface markers characteristic of embryonic, mesenchymal, neuronal or hematopoietic stem cells revealed negligible expression on VSEL cells. These cells failed to expand in vitro under a wide range of culture conditions known to support embryonic or adult stem cell types and a microarray analysis revealed the transcriptional profile of VSELs to be clearly distinct both from well-defined populations of pluripotent and adult stem cells and from the mature hematopoietic lineages. Finally, we detected an aneuploid karyotype in the majority of purified VSEL cells by fluorescence in situ hybridisation. These data support neither an embryonic nor an adult stem cell like phenotype, suggesting rather that hUCB VSEL are an aberrant and inactive population that is not comparable to murine VSEL. VSEL cells (Lin-CD45-CXCR4+CD34-) and CD34+ VSEL cells (Lin-CD45-CXCR4+CD34+) from three individual fresh cord blood units were double sorted to highest purity and subjected to array analysis.
Project description:High-grade serous ovarian cancer (HGSOC) exhibits significant genomic heterogeneity within a patient at presentation. Recent work has suggested that this heterogeneity is linked to the development of resistance and disease progression in that chemotherapy selects for minor resistant subclones embodied in presentation disease leading to short progression-free survival and resistant relapse. Cell line models support this by showing that relapse is not an immediate descendant of presentation disease, but so far no immediate clinical evidence has been provided that convincingly demonstrates the origin of relapse. It is further still unclear what evolutionary processes shape the mutational landscape of HGSOC in vivo and to what extent the degree of genomic heterogeneity impacts a patient's clinical outcome. We address these questions by inferring evolutionary trees of metastatic disease from structural variations between 138 cancer samples obtained from 17 patients undergoing neoadjuvant chemotherapy for HGSOC. Using novel phylogenetic methods, we quantify genomic changes in the course of chemotherapy and the degree of clonal expansion and show that these indices determine patient outcome with high accuracy. We demonstrate that relapse is indeed a minor subclone of presentation disease by verifying that the focal NF1 deletion of a relapse case was already present at biopsy. By leveraging the information contained in the evolutionary trees, we unveil the etiology of genetic heterogeneity and the tumorigenic potential of HGSOC cell populations. This is the first comprehensive study showing the origin, strength and effect of genetic heterogeneity in HGSOC in a clinical setting. In addition to its immediate clinical significance, it strengthens previous statements that single sample biopsies are seemingly insufficient to predict disease progression and stresses the importance of establishing multiple sampling as a routine approach in the clinic. Clinical data and tissue samples were collected on the prospective CTCR-OV03 and CTCR-OV04 clinical studies designed to identify biomarkers of heterogeneity.
Project description:Tumor-induced immunosuppression remains a major challenge for immunotherapy of cancer patients. To further elucidate why an allogeneic gene-modified (Interleukin-7(IL-7)/CD80 co-transfected) renal cell cancer vaccine failed to induce clinically relevant TH1-polarized immune responses, peripheral blood mononuclear cells (PBMCs) from enrolled study patients were analyzed by gene expression profiling (GEP) both prior and after vaccination. At baseline before vaccination, a profound downregulation of gene signatures associated with antigen presentation, immune response/T cells, cytokines/chemokines and signaling/transcription factors was observed in renal cell cancer patients as compared to healthy controls. Vaccination led to a partial reversion of preexisting immunosuppression, however, GEP indicated that an appropriate TH1 polarization could not be achieved. Most interestingly, our results suggest that the nuclear factor kappa B (NF-κB) signaling pathway might be involved in the impairment of immunological responsiveness and the observed TH2 deviation. In summary, our data suggest that GEP might be a powerful tool for the prediction of immunosuppression and the monitoring of immune responses within immunotherapy trials. Gene expression was profiled using Affymetrix Human Gene v1.1 ST microarrays in the following settings: 9 RCC patients were profiled before and after vaccination (pairs of measurements) and additionally 9 healthy control samples were profiled.
Project description:Urinary tract infections (UTIs) constitute a highly relevant model of microbial adaptation, in which the contrasting effects of pathogens and commensals on host tissues are clearly displayed. While virulent Escherichia coli cause severe, potentially life-threatening disease by breaking the inertia of the mucosal barrier and infecting the kidneys, the most common outcome of bacteriuria is an asymptomatic carrier state resembling commensalism at other mucosal sites. It remains unclear if the lack of destructive inflammation merely reflects low virulence or if carrier strains actively inhibit disease associated responses in the host. To address this question, we examined the effects of asymptomatic bacterial carriage on host gene expression. Therapeutic urinary tract inoculation with the prototype ABU strain E. coli 83972 is a safe alternative approach in patients with therapy-resistant recurrent UTI. The strain establishes persistent bacteriuria, protecting patients against super-infection with more virulent strains. Using this protocol, we examined if the establishment of asymptomatic bacterial carriage alters host gene expression. After antibiotic treatment to remove prior infection, patients were inoculated with E. coli 83972 through a catheter. Blood samples were obtained before and 24 h after inoculation.
Project description:We performed a global gene-expression analysis of mammary gland and liver tissue collected from dairy cows that had been exposed to a controlled E. coli infection. At time = 0, each of the periparturient dairy cows received 20-40 colony-forming units of live E. coli in one front quarter of the udder. Biopsy samples of healthy and infected udder tissue were collected at T = 24 h post-infection (p.i.) and at T = 192 h p.i. to represent the acute phase response (APR). A time series of liver biopsies was collected at -144, 12, 24, and 192 h relative to time of inoculation. Hf=right forward teat Vf=left forward teat
Project description:NK cells were first isolated from PBMCs using EasySep™ Human NK cell enrichment kit (STEMCELL biotechnology). The magnetically isolated NK cells were stained with anti-CD3 FITC, anti-CD56 Pe-Cy7 and LIVE/DEAD® red stain for a further enrichment, whereby the CD3 negative and CD56 positive live cells were sorted with MoFlo™ cell sorter (Beckman Coulter). The sorted NK cell populations were sent to AROS Applied Biotechnology A/S (Aarhus N, Denmark) to be analysed using GeneChip® Human Transcriptome Array 2.0 (Affymetrix, USA). The transcription profile of NK cells from day 14 post stem cell transplantation was compared with those from healthy donors.
Project description:Chronic lymphocytic leukemia (B-CLL) and small lymphocytic lymphoma (SLL) are part of the same disease classification but are defined by differential distribution of tumor cells. B-CLL is characterized by significant immune suppression and dysregulation but this is nottypical of patients with SLL. Natural killer cells (NK) are important mediators of immune function but have been relatively poorly studied in patients with B-CLL/SLL.
Project description:Cancer-related fatigue is one of the most frequent complaints among breast cancer survivors, with a major negative impact on general life. However, the etiology behind this syndrome is still unraveled. Gene expression analysis was performed on whole blood samples from breast cancer survivors classified as either fatigued or non-fatigued at two consecutive time points. The analysis identified several gene sets concerning plasma and B cell pathways as different between the fatigue and non-fatigue groups, suggesting that a deregulation in these pathways might underlie the fatigue syndrome. The fatigue group also showed a higher mean level of leucocytes, lymphocytes and neutrophiles compared with the non-fatigue group, thus further implicating the immune system in the biology behind the fatigue syndrome. Keywords: Blood RNA and late side effects Breast cancer survivors treated with adjuvant radiotherapy at The Norwegian Radium Hospital between 1998 and 2002 were invited to participate in a study assessing late treatment effects in breast cancer survivors. In the present study, gene expression analysis was performed on whole blood samples from breast cancer survivors with and without persistent fatigue, to look for different expression patterns that might shed light on the biology behind cancer-related fatigue.
Project description:Characterization of the gene expression changes accompanying the differentiation of hPSC-sensory from embryonic stem cells through to neuronal precursor cells. We also compare the time course gene expression profile to that of the relevant primary human tissue, human dorsal root ganglia (hDRG). A reference brain sample is also included.