CD200 as a Potential New Player in Inflammation during Rotator Cuff Tendon Injury/Repair: An In Vitro Model.

Rotator cuff tendon (RCT) disease results from multifactorial mechanisms, in which inflammation plays a key role. Pro-inflammatory cytokines and tendon stem cell/progenitor cells (TSPCs) have been shown to participate in the inflammatory response. However, the underlying molecular mechanism is still not clear. In this study, flow cytometry analyses of different subpopulations of RCT-derived TSPCs demonstrate that after three days of administration, TNFα alone or in combination with IFNγ significantly decreases the percentage of CD146+CD49d+ and CD146+CD49f+ but not CD146+CD109+ TSPCs populations. In parallel, the same pro-inflammatory cytokines upregulate the expression of CD200 in the CD146+ TSPCs population. Additionally, the TNFα/IFNγ combination modulates the protein expression of STAT1, STAT3, and MMP9, but not fibromodulin. At the gene level, IRF1, CAAT (CAAT/EBPbeta), and DOK2 but not NF-κb, TGRF2 (TGFBR2), and RAS-GAP are modulated. In conclusion, although our study has several important limitations, the results highlight a new potential role of CD200 in regulating inflammation during tendon injuries. In addition, the genes analyzed here might be new potential players in the inflammatory response of TSPCs.

Clinical-Grade Expanded Regulatory T Cells Are Enriched with Highly Suppressive Cells Producing IL-10, Granzyme B, and IL-35.

In the setting of T cell-depleted, full-haplotype mismatched transplantation, adoptive immunotherapy with regulatory T cells (Tregs) and conventional T cells (Tcons) can prevent graft-versus-host disease (GVHD) and improve post-transplantation immunologic reconstitution and is associated with a powerful graft-versus-leukemia effect. To improve the purity and the quantity of the infused Tregs, good manufacturing practices (GMP)-compatible expansion protocols are needed. Here we expanded Tregs using an automated, clinical-grade protocol. Cells were extensively characterized in vitro, and their efficiency was tested in vivo in a mouse model. Tregs were selected by CliniMacs (CD4+CD25+, 94.5 ± 6.3%; FoxP3+, 63.7 ± 11.5%; CD127+, 20 ± 3%; suppressive activity, 60 ± 7%), and an aliquot of 100 × 106 was expanded for 14 days using the CliniMACS Prodigy System, obtaining 684 ± 279 × 106 cells (CD4+CD25+, 99.6 ± 0.2%; FoxP3+, 82 ± 8%; CD127+, 1.1 ± 0.8%; suppressive activity, 75 ± 12%). CD39 and CTLA4 expression levels increased from 22.4 ± 12% to 58.1 ± 13.3% (P < .05) and from 20.4 ± 6.7% to 85.4 ± 9.8% (P < .01), respectively. TIM3 levels increased from .4 ± .05% to 29 ± 16% (P < .05). Memory Tregs were the prevalent population, whereas naive Tregs almost disappeared at the end of the culture. mRNA analysis displayed significant increases in CD39, IL-10, granzyme B, and IL-35 levels at the end of culture period (P < .05). Conversely, IFNγ expression decreased significantly by day +14. Expanded Tregs were sorted according to TIM3, CD39, and CD62L expression levels (purity >95%). When sorted populations were analyzed, TIM3+ cells showed significant increases in IL-10 and granzyme B (P < .01) .When expanded Tregs were infused in an NSG murine model, mice that received Tcons only died of GVHD, whereas mice that received both Tcons and Tregs survived without GVHD. GMP grade expanded cells that display phenotypic and functional Treg characteristics can be obtained using a fully automated system. Treg suppression is mediated by multiple overlapping mechanisms (eg, CTLA-4, CD39, IL-10, IL-35, TGF-ß, granzyme B). TIM3+ cells emerge as a potentially highly suppressive population. © 2020 American Society for Transplantation and Cellular Therapy. Published by Elsevier Inc.

Case Report: Invasive fungal infection after anti-CD19 CAR-T cell therapy. Implication for antifungal prophylaxis.

CAR-T therapy has revolutionized the treatment of relapsed/refractory B-cell malignancies. Patients who are receiving such therapy are susceptible to an increased incidence of infections due to post-treatment immunosuppression. The need for antifungal prophylaxis during the period of neutropenia remains to be determined. The clinical outcome of a 55-year-old patient with relapsed/refractory DLBCL who received axicabtagene ciloleucel is described here. The patient developed CRS grade II and ICANS grade IV requiring tocilizumab, prolonged use of steroids and anakinra. An invasive pulmonary aspergillosis arose after 1 month from CAR-T reinfusion, resolved with tracheal sleeve pneumonectomy. The patient is now in Complete Remission. This case suggests that antifungal prophylaxis should be considered. We have now included micafungin as a standard prophylaxis in our institution.

NOTCH1 Activation Negatively Impacts on Chronic Lymphocytic Leukemia Outcome and Is Not Correlated to the NOTCH1 and IGHV Mutational Status.

NOTCH1 mutations and deregulated signal have been commonly found in chronic lymphocytic leukemia (CLL) patients. Whereas the impact of NOTCH1 mutations on clinical course of CLL has been widely studied, the prognostic role of NOTCH1 activation in CLL remains to be defined. Here, we analyzed the activation of NOTCH1/NOTCH2 (ICN1/ICN2) and the expression of JAGGED1 (JAG1) in 163 CLL patients and evaluated their impact on TTFT (Time To First Treatment) and OS (Overall Survival). NOTCH1 activation (ICN1+) was found in 120/163 (73.6%) patients. Among them, 63 (52.5%) were NOTCH1 mutated (ICN1+/mutated) and 57 (47.5%) were NOTCH1 wild type (ICN1+/WT). ICN1+ patients had a significant reduction of TTFT compared to ICN1-negative (ICN1-). In the absence of NOTCH1 mutations, we found that the ICN1+/WT group had a significantly reduced TTFT compared to ICN1- patients. The analysis of IGHV mutational status showed that the distribution of the mutated/unmutated IGHV pattern was similar in ICN1+/WT and ICN1- patients. Additionally, TTFT was significantly reduced in ICN1+/ICN2+ and ICN1+/JAG1+ patients compared to ICN1-/ICN2- and ICN1-/JAG1- groups. Our data revealed for the first time that NOTCH1 activation is a negative prognosticator in CLL and is not correlated to NOTCH1 and IGHV mutational status. Activation of NOTCH2 and JAGGED1 expression might also influence clinical outcomes in this group, indicating the need for further dedicated studies. The evaluation of different NOTCH network components might represent a new approach to refine CLL risk stratification.

Expression profile of the embryonic markers nanog, OCT-4, SSEA-1, SSEA-4, and frizzled-9 receptor in human periodontal ligament mesenchymal stem cells.

Mesenchymal stem cells (MSCs) are self-renewing cells with the ability to differentiate into various mesodermal-derived tissues. Recently, we have identified in adult human periodontal ligament (PDL) a population of stem cells (PDL-MSCs) with the ability to differentiate into osteoblasts and adipocytes. The aim of the present work was to further characterize this population and the expression profile of its cells. To achieve our objective we have used flow cytometry, magnetic cell sorting, cytokine antibody array, and light and electron microscope immunostaining. Our results show that the PDL-MSCs contain a subpopulation of frizzled-9 (CD349) positive cells expressing a panel of key mesenchymal and embryonic markers including CD10, CD26, CD29, CD44, CD73, CD90, CD105, CD166, SSEA-1, and SSEA-4. They are additionally positive for nanog and Oct-4; two critical transcription factors directing self-renewal and pluripotency of embryonic stem cells, and they also express the cytokines EGF and IP-10. The presence of nanog, Oct-4, SSEA-1, and SSEA-4 suggests that PDL-MSCs are less differentiated than bone marrow-derived MSCs. Taken together, these data indicate the presence of immature MSCs in PDL and suggest that the frizzled-9/Wnt pathway plays an important role in regulating proliferation and differentiation of these cells.

Immunotherapy with cytokine induced killer cells in solid and hematopoietic tumours: a pilot clinical trial.

BACKGROUND AND OBJECTIVES: CIK cells are a novel population of efficient immune effector cells with high antitumour activity mainly due to the high proliferation of CD3(+)CD56(+) cells, so may play a role in the development of new forms of adoptive cellular immunotherapy. We started a pilot clinical trial with autologous CIK cells in patients with refractory lymphoma and metastatic solid tumours. This study was aimed at determining the feasibility of generating a sufficient number of CIK cells in heavily pretreated patients and at assessing treatment toxicity. DESIGN AND METHODS: CIK cells were generated from peripheral blood mononuclear cells (MNC) and incubated in the presence of IFN-gamma followed by OKT3 and IL-2. Treatment schedule consisted of three cycles of CIK cells infusions at an interval of 3 weeks. RESULTS: At present 12 patients were enrolled: 6 advanced lymphomas, 5 metastatic kidney carcinoma and 1 hepatocellular carcinoma (HCC). The median number of transferred cells per patient was 28 x 10(9) (range, 6-61). Protocol adherence was excellent and the toxicity profile was favourable. After CIK cells infusion, the absolute median count of lymphocytes, CD3(+), CD8(+) and CD3(+)CD56(+) cells significantly increased in patient's peripheral blood. Clinical outcome appeared promising: three patients had complete response (CR) and two patients had stabilization of disease with a median follow-up of 33 months (range, 9-44). INTERPRETATIONS AND CONCLUSIONS: These preliminary data showed that adoptive immunotherapy with CIK cells is a safe therapy with some suggestion of efficacy that significantly enhances immune functions increasing absolute numbers of effector cells without side effects. If confirmed in larger scale studies, these promising results may have a favourable impact on conventional treatment strategy of malignancies.

Comparison between the BACTEC 9240 and the Pall eBDS system for detection of bacterial platelet concentrate contamination.

BACKGROUND: Only two commercially available automated systems have been cleared by the FDA for screening of bacterial contamination in platelet (PLT) products. These are the Pall eBDS (Pall Corp.), based on measurement of oxygen consumption by contaminant organisms, and the BacT/ALERT (bioMérieux), revealing increasing carbon dioxide concentration due to bacterial growth. STUDY DESIGN AND METHODS: The authors compared the performance of the Pall eBDS with the BACTEC 9240 (bioMérieux) in detecting PLT contamination. Serial dilutions of 10 bacterial species frequently associated with PLT contamination were prepared in an apheresis PLT unit per organism. Units were from single donors. After 30 minutes from seeding PLT units, a volume of suspension achieving a final bacterial concentration of 1 to 10 colony-forming units/mL for each unit was inoculated in two Pall bags and a BACTEC bottle, and the same was done after 24 hours from seeding. Measurements were performed at 24 and 30 hours. RESULTS: Significant differences between the two instruments were only found when screening PLT units after 24 hours from seeding. The Pall system showed a higher sensitivity than BACTEC 9240, because it revealed 97 and 98% of positive samples at 24 and 30 hours of incubation, respectively, whereas the second detected 86 and 90% of contaminated products. Significance was lost after 35-hour incubation with the BACTEC 9240. CONCLUSIONS: By comparing the two instruments, their performances were found to be comparable; the Pall system appeared as a more suitable method when using 24 to 30 hours as times for readings, but the significant difference was lost after 35-hour incubation.

NOTCH and Graft-Versus-Host Disease.

In allogeneic hematopoietic stem cell transplantation, which is the major curative therapy for hematological malignancies, T cells play a key role in the development of graft-versus-host disease (GvHD). NOTCH pathway is a conserved signal transduction system that regulates T cell development and differentiation. The present review analyses the role of the NOTCH signaling as a new regulator of acute GvHD. NOTCH signaling could also represent a new therapeutic target for GvHD.

NOTCH1 Is Aberrantly Activated in Chronic Lymphocytic Leukemia Hematopoietic Stem Cells.

To investigate chronic lymphocytic leukemia (CLL)-initiating cells, we assessed NOTCH1 mutation/expression in hematopoietic stem cells (HSCs). In NOTCH1-mutated CLL, we detected subclonal mutations in 57% CD34+/CD38- HSCs. NOTCH1 mutation was present in 66% CD34+/CD38+ progenitor cells displaying an increased mutational burden compared to HSCs. Flow cytometric analysis revealed significantly higher NOTCH1 activation in CD34+/CD38- and CD34+/CD38+ cells from CLL patients, regardless NOTCH1 mutation compared to healthy donors. Activated NOTCH1 resulted in overexpression of the NOTCH1 target c-MYC. We conclude that activated NOTCH1 is an early event in CLL that may contribute to aberrant HSCs in this disease.

Treg-protected donor lymphocyte infusions: a new tool to address the graft-versus-leukemia effect in the absence of graft-versus-host disease in patients relapsed after HSCT.

In high-risk acute leukemia patients undergoing haploidentical hematopoietic stem cell transplantation (HSCT), adoptive immunotherapy with T regulatory cells (Tregs) and T conventional cells (Tcons) prevented acute and chronic graft-versus-host disease (GvHD), favored post-transplant immunological reconstitution and was associated with a powerful graft-versus-leukemia (GvL) effect. With a particularly innovative approach, we developed a treatment with a Treg-protected donor lymphocyte infusion (DLI) for patients with early relapse after HSCT and we report here the results obtained in the first patient with APL (M3v) relapsed after a second matched allogeneic HSCT (15% blasts and 75% of donor cells in bone marrow). The patient received a first infusion of 2.5 × 106/kg Tregs derived from matched donor followed 7 days later by 5 × 106/kg Tcons. GvL effect was strongly evident as the percentage of leukemic cells decreased to 5%. A second infusion of Tregs (2.5 × 106/kg) and Tcons (2 × 106/kg) was performed. No GvHD was observed. Disease evaluation showed the absence of blastic cells at flow-cytometry, a normal caryotype and full donor chimerism. We also observed NOTCH1 down-regulation in peripheral blood. This new immunotherapy approach showed that Treg-protected DLI is effective in preventing GvHD and is associated with a strong GvL effect.

Proteome of human stem cells from periodontal ligament and dental pulp.

BACKGROUND: Many adult tissues contain a population of stem cells with the ability to regenerate structures similar to the microenvironments from which they are derived in vivo and represent a promising therapy for the regeneration of complex tissues in the clinical disorder. Human adult stem cells (SCs) including bone marrow stem cells (BMSCs), dental pulp stem cells (DPSCs) and periodontal ligament stem cells (PDLSCs) have been characterized for their high proliferative potential, expression of characteristic SC-associated markers and for the plasticity to differentiate in different lineage in vitro. METHODOLOGY/PRINCIPAL FINDINGS: The aim of this study is to define the molecular features of stem cells from oral tissue by comparing the proteomic profiles obtained with 2-DE followed by MALDI-TOF/TOF of ex-vivo cultured human PDLSCs, DPSCs and BMSCs. Our results showed qualitative similarities in the proteome profiles among the SCs examined including some significant quantitative differences. To enrich the knowledge of oral SCs proteome we performed an analysis in narrow range pH 4-7 and 6-9, and we found that DPSCs vs PDLSCs express differentially regulated proteins that are potentially related to growth, regulation and genesis of neuronal cells, suggesting that SCs derived from oral tissue source populations may possess the potential ability of neuronal differentiation which is very consistent with their neural crest origin. CONCLUSION/SIGNIFICANCE: This study identifies some differentially expressed proteins by using comparative analysis between DPSCs and PDLSCs and BMSCs and suggests that stem cells from oral tissue could have a different cell lineage potency compared to BMSCs.

Cell therapy: cGMP facilities and manufacturing.

Advanced therapies constitute one of the most complex, organizational, and regulatory areas currently approached by clinical researchers in order to explore new therapeutic applications. Basic scientists and clinicians trying to implement cell therapies into clinical practice, may feel overwhelmed by the apparently endless regulatory requirements that apply. However, regulatory agencies have primary responsibility on patient safety and law enforcement are, and should be, their main considerations. Cell- and tissue-based therapies have the potential to treat many conditions, where present conventional treatments are inadequate. The current approach to cell- and tissue-based therapy development requires using good manufacturing production facilities through master and working cell banks. Facilities need to be purpose-designed and accredited by their national medicinal regulatory body and production scientists need to work in close tandem with quality assurances and ethics committees to absolutely ensure the safety of this cellular products.

Evaluation of an automated closed fluid management device for processing expanded cytokine-induced killer cells to use in immunotherapy programs for cancer.

BACKGROUND: Cytokine-induced killer (CIK) cells are a heterogeneous population of immune cells derived from peripheral blood lymphocytes with a high proliferative potential ex vivo. This study shows a rapid and reproducible protocol for adoptive immunotherapy with CIK cells in patients with hematologic malignancies. For this purpose a new automatic cell processing device (CytoMate, Baxter Oncology) was tested to improve extensive manipulations of these cells. STUDY DESIGN AND METHODS: Twenty CIK expansions obtained from healthy donors and patients with hematologic malignancies were washed and refilled with fresh medium during culture with the CytoMate. Recovery, viability, and cytotoxic activity were evaluated. Six cryopreserved CIK procedures were thawed and processed for washing out dimethyl sulfoxide automatically. Recovery of cells, viability, and early apoptosis were measured immediately after washing, and cytotoxic activity against target cell lines K562 and Daudi was tested after short culture. RESULTS: Prewash volume of CIK cultures was 3600 mL (range, 1970-6000 mL). After automatic wash, the total CIK cell recovery was 85.3 percent (range, 78.5%-97.5%), and living cells were greater than 95 percent. After thawing, the median recoveries of total nucleated cells and natural killer T (NKT) cells were, respectively, 80.7 percent (range, 65%-95.5%) and 90.5 percent (range, 70.5%-98.5%). Thawed cells preserved their cytotoxic activity after cryopreservation (approx. 50% lysis at effector:target ratio of 40:1). CONCLUSION: The automatic wash with the CytoMate showed a good recovery of viable CIK cells during expansion and allowed an efficient manipulation of thawed cells. The use of this simple and efficient washing technique is suitable for clinical-grade processing in cellular therapy protocols.

Cancer therapy: switching off oncogenes.

Cancer derives from a cell clone that has accumulated genetic and epigenetic changes that influence its phenotype and finally enable it to escape from the normal controls of proliferation. A recent paper shows that, in myc-induced tumours, the inactivation of this oncogene produces the regression of the tumours and the differentiation of the tumour cells into mature osteocytes.1 In addition, a further reactivation of myc in these cells does not restore the malignant phenotype but induces apoptosis. This discovery could lead to an innovative therapeutic strategy.