scholarly journals The combination of Radix Astragali and Radix Angelicae Sinensis attenuates the IFN-γ-induced immune destruction of hematopoiesis in bone marrow cells

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Juan Liu ◽  
Jie Wei ◽  
Changzhi Wang ◽  
Xiaoying Meng ◽  
Hening Chen ◽  
...  
Keyword(s):  
Bone Marrow ◽  
T Cells ◽  
Cell Immune Response ◽  
Ionization Mass ◽  
Radix Astragali ◽  
Hematopoietic Stem ◽  
Radix Angelicae Sinensis ◽  
Ifn Γ ◽  
Immune Destruction ◽  
Angelicae Sinensis

Abstract Background Radix Astragali and Radix Angelicae Sinensis are two herbs that compose Danggui Buxue Tang (an herbal formula for treatment of anemia diseases). In this study, we explored the molecular mechanism and effective targets to immune destruction of bone marrow (BM) cells treated with Radix Astragali, Radix Angelicae Sinensis or a combination of two agents. The potential synergic advantages of two herbs should also be explored. Methods The constituents of Radix Astragali and Radix Angelicae Sinensis were analyzed by high performance liquid chromatography-electrospray ionization/mass spectrometer system BM cells were separated from limbs of BALB/c mice, and immune destruction was induced with IFN-γ. The percentages of hematopoietic stem cells (HSCs) and CD3+ T cells were detected by flow cytometry. The distribution of T-bet and changes in the combination of SAP and SLAM in BM cells were observed by immunofluorescence. Western blotting was used to assay the expression of key molecules of the eIF2 signaling pathway in BM cells. Results Seven constituents of Radix Astragali and six constituents of Radix Angelicae Sinensis were identified. The percentages of HSCs increased significantly after treatment with Radix Angelicae Sinensis, especially at high concentrations. The percentages of CD3+ T cells were significantly decreased after Radix Astragali and Radix Angelicae Sinensis treatment. However, the synergistic function of two-herb combinations was superior to that of the individual herbs alone. The distribution of T-bet in BM cells was decreased significantly after Radix Angelicae Sinensis treatment. The number of SLAM/SAP double-stained cells was increased significantly after Radix Astragali treatment at low concentrations. The phosphorylation levels of eIF2α were also reduced after Radix Astragali and Radix Angelicae Sinensis treatment. Conclusions Radix Astragali and Radix Angelicae Sinensis could intervene in the immunologic balance of T lymphocytes, inhibit the apoptosis of BM cells induced by immune attack, restore the balance of the T cell immune response network and recover the hematopoietic function of HSCs. The synergistic effects of Radix Astragali and Radix Angelicae Sinensis were superior to those of each herb alone.

Novel Double Labeled Mixed Lymphocyte in Vitro Assay to Predict the Dominant Graft in 2 Unit UCB Transplantation

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 4699-4699
Author(s):  
Shicheng Yang ◽  
Xiao Huang ◽  
Hongyan Lu ◽  
Amandeep Salhotra ◽  
Alexander Wendling ◽  
...  
Keyword(s):  
Stem Cells ◽  
Bone Marrow ◽  
T Cells ◽  
Peripheral Blood ◽  
In Vitro Assay ◽  
Proliferation Index ◽  
Vitro Assay ◽  
Hematopoietic Stem ◽  
Ifn Γ

Abstract Abstract 4699 Introduction: Umbilical cord blood cells (UCB) from allogeneic donors have been established as an alternative source for HSC transplantation in patients who lack suitably HLA matched bone marrow or peripheral blood stem cells from adult donors. Transplantation using 2 unit UCB has been shown to compensate the low engraftment and slow hematopoietic recovery resulting from 1 unit UCB transplantation in full stature adult patients. At present, there are no unit specific factors that reliably predicts for the “winning unit” in 2 unit UCB transplantation, e.g. cell viability, number of infused total nucleated cells, CD34+ or CD3+ cells, sex mismatch, ABO blood group, and degree of HLA mismatch. In vivo mouse models suggest that CD34 negative subsets play an important role. Among CD34 negative subsets, CD8 T subset accounts for approximately 34.0+/−23.3% of T lymphocytes from UCB. In bone marrow transplantation CD8 T cells have been found to facilitate donor hematopoietic cell engraftment. Moreover, it has been reported that 1 dominant unit coincides with a specific CD8 T cell response against the non-engrafted unit which was not observed from CD4 or NK cells. Methods: In this study, we used volunteer donated UCB research units (kindly provided by P. Rubinstein, MD, New York Blood Center). Mononuclear cells (MNC) were purified by Ficoll gradient centrifugation, and CD3 T cells were isolated with CD3 MicroBeads (Miltenyi Biotec; autoMACS). The purified CD3 (confirmed by FACS >95% purity) cells were labeled with CFSE and DDAO-SE. After labeling, the cells from two different donors were mixed in 96-well U-bottom plates for continued culture in 37 °C 5% CO2. The expansion from each labeled donor cells was evaluated using flow cytometry; the dead cells were gated out using propidium iodide, and the data was analyzed using FlowJo software. For proper T cells activation, we also compared different activation conditions using i.) anti-CD3/CD28 Beads, ii.) anti-CD3 antibody plus anti-CD28 antibody, and iii.) cytokine IL-2. The schematic illustration of methods is shown in Figure 1. Results and discussion: We noted that T cells from UCB are primarily at naïve stage as determined by CD45RA (93.8 +/− 7.11%) and CCR7 (84.9 +/− 12.0%) expression. We also determined the optimal activation condition using a modified mixed lymphocyte reaction from 2 UCB units. Four days after incubation, the proliferation from 2 units labeled with CFSE and DDAO-SE could be reproducibly distinguished using FL1 channel for CFSE and FL4 channel for DDAO-SE (Figure 1). The optimal concentration for labeling using CFSE (1 mM) and DDAO (1 μM or 3 mM) was determined by titration. To avoid cell toxicity resulting from CFSE and DDAO-SE labeling, as well as self-crossing from each donor using two dyes, we examined additional mixed lymphocyte analyses in which each donor was labeled with CFSE or DDAO-SE respectively and vice versa. As shown in Figure 1, we found consistently that the predicated dominant unit accounted for the majority of culture (73.2% stained with DDAO; 63.5% stained with CFSE) after 4 days co-culture. The dominance was not correlated with cell proliferation indicated by the proliferation index (1.12 for dominant and 1.48 for another unit). After confirmation of this in vitro assay, further studies were conducted to evaluate the IFN-γ release of 2 UCB units in this optimized mixed lymphocyte assay in the condition using cytokine IL-2. Interestingly, we could only detect IFN-γ by intracellular staining in one unit when co-culture was set-up using CD3 T cells from each unit; the expression of IFN-γ was not detected when we used CD3 T cells from 1 unit. The correlation between dominance and the expression of IFN-γ is currently under investigation. Conclusion: UCB Transplantation is an important alternative for patients lacking bone marrow or peripheral blood stem cell donors. With the establishment of this novel modified mixed lymphocyte in vitro assay for prediction of the “winning” immune dominant unit, routine analyses can be performed to guide unit selection. Further interventions can be exploited to preferentially treat the expected dominant unit with glycosylation, cytokines, prostaglandins, or C3a compliments to further enhance hematopoietic stem cells trafficking and engraftment to the marrow. Disclosures: No relevant conflicts of interest to declare.

scholarly journals Chinese Herbal Formula, Modified Danggui Buxue Tang, Attenuates Apoptosis of Hematopoietic Stem Cells in Immune-Mediated Aplastic Anemia Mouse Model

2017 ◽  
Vol 2017 ◽  
pp. 1-12 ◽  
Author(s):  
Jingwei Zhou ◽  
Xue Li ◽  
Peiying Deng ◽  
Yi Wei ◽  
Juan Liu ◽  
...  
Keyword(s):  
Stem Cells ◽  
Herbal Formula ◽  
Radix Astragali ◽  
Hematopoietic Stem ◽  
Danggui Buxue Tang ◽  
Chinese Herbal Formula ◽  
Radix Angelicae Sinensis ◽  
Chinese Herbal ◽  
Immune Mediated ◽  
Angelicae Sinensis

A derivative formula, DGBX, which is composed of three herbs (Radix astragali,Radix Angelicae sinensis, andCoptis chinensisFranch), is derived from a famous Chinese herbal formula, Danggui Buxue Tang (DBT) (Radix astragaliandRadix Angelicae sinensis). We aimed to investigate the effects of DGBX on the regulation of the balance between proliferation and apoptosis of hematopoietic stem cells (HSCs) due to the aberrant immune response in a mouse model of aplastic anemia (AA). Cyclosporine (CsA), an immunosuppressor, was used as the positive control. Our results indicated that DGBX could downregulate the production of IFNγin bone marrow cells by interfering with the binding between SLAM and SAP and the expressions of Fyn and T-bet. This herbal formula can also inhibit the activation of Fas-mediated apoptosis, interferon regulatory factor-1-induced JAK/Stat, and eukaryotic initiation factor 2 signaling pathways and thereby induce proliferation and attenuate apoptosis of HSCs. In conclusion, DGBX can relieve the immune-mediated destruction of HSCs, repair hematopoietic failure, and recover the hematopoietic function of HSCs in hematogenesis. Therefore, DGBX can be used in traditional medicine against AA as a complementary and alternative immunosuppressive therapeutic formula.

Diversity, localization and (patho)physiology of mature lymphocyte populations in the bone marrow

Blood ◽  
2021 ◽  
Author(s):  
Christian M. Schürch ◽  
Chiara Caraccio ◽  
Martijn A. Nolte
Keyword(s):  
Bone Marrow ◽  
T Cells ◽  
Plasma Cells ◽  
Cell Types ◽  
Lymphoid Organ ◽  
Lymphoid Cells ◽  
Term Survival ◽  
Hematopoietic Stem ◽  
Mature Lymphocyte ◽  
Lymphocyte Populations

The bone marrow (BM) is responsible for generating and maintaining lifelong output of blood and immune cells. Besides its key hematopoietic function, the BM acts as an important lymphoid organ, hosting a large variety of mature lymphocyte populations, including B-cells, T-cells, NK(T)-cells and innate lymphoid cells (ILCs). Many of these cell types are thought to only transiently visit the BM, but for others, like plasma cells and memory T-cells, the BM provides supportive niches that promote their long-term survival. Interestingly, accumulating evidence points towards an important role for mature lymphocytes in the regulation of hematopoietic stem cells (HSCs) and hematopoiesis in health and disease. In this review, we describe the diversity, migration, localization and function of mature lymphocyte populations in murine and human BM, focusing on their role in immunity and hematopoiesis. We also address how various BM lymphocyte subsets contribute to the development of aplastic anemia and immune thrombocytopenia, illustrating the complexity of these BM disorders, but also the underlying similarities and differences in their disease pathophysiology. Finally, we summarize the interactions between mature lymphocytes and BM resident cells in HSC transplantation and graft-versus-host disease. A better understanding of the mechanisms by which mature lymphocyte populations regulate BM function will likely improve future therapies for patients with benign and malignant hematological disorders.

scholarly journals T Cell Subsets and Associated Cytokines in Chronic Graft-Versus-Host-Disease Using G-CSF Primed Bone Marrow in Allogeneic Hematopoietic Stem Cell Transplantation

Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 4580-4580
Author(s):  
Monica M Rivera Franco ◽  
Eucario Leon Rodriguez ◽  
Diana Gomez Martin ◽  
Javier Merayo Chalico ◽  
Jorge Alcocer Varela
Keyword(s):  
Bone Marrow ◽  
Flow Cytometry ◽  
Stem Cell ◽  
Th17 Cells ◽  
Mononuclear Cells ◽  
Chronic Gvhd ◽  
The Other ◽  
Hematopoietic Stem ◽  
Graft Versus Host ◽  
Ifn Γ

Abstract Background Graft versus host disease (GVHD) is the major complication of allogeneic hematopoietic stem cell transplantation. It is characterized by an imbalance between the effector and regulatory arms of the immune system which results in the over production of inflammatory cytokines. Regulatory T (T regs) cells and T helper 17 (Th17) cells are two recently described lymphocyte subsets with opposing actions. Both can develop from naïve CD4+ T cell precursors under the influence of TGFβ1. Th17 lymphocytes, are key effector cells in rodent models of human diseases including GVHD. The other subset, T regs, is essential for dominant immunologic tolerance. At our institution, patients transplanted using G-CSF primed bone marrow (G-BM), have a lower incidence of acute and chronic GVHD when compared to those transplanted with peripheral blood and not primed bone marrow. Some microenvironment characteristics of this hematopoietic stem cells (HSC) source remain unknown, as well as the difference between Tregs, Th17 and cytokine levels in patients who develop GVHD and those who do not. Objective To analyze the characteristics of thirty-eight G-BM donor samples, identifying lymphocytes subsets and associated cytokines, and comparing patients who developed chronic GVHD (cGVHD) and those who did not. Materials and Methods A prospective analysis was performed in 38 G-BM samples from donors from 1999 to 2016. Mononuclear cells were defrosted, counted, and viability was evaluated. A 24 hour resting with RPMI, and posterior activation with PMA (50 ng/ml) for 48 hours was performed. Cells were harvested and cytokines were evaluated by flow cytometry (CBA assay). From each sample, one million mononuclear cells were permeabilized, fixed, and stained with CD4-FITC, IL17A-PE, IFN-γ APC, and IL-4 PECy7, for their posterior phenotipication by flow cytometry. The samples were obtained in a BD LSR Fortessa cytometry, and analyzed with the Flow-Jo software. Patients (recipients) information was analyzed using SPSS v.21. Results GVHD incidence was reported as following: Three (8%) patients developed acute GVHD (2 grade II, and 1 grade IV), 11 patients (29%) developed chronic GVHD (9% extensive, and 91% limited), and 24 patients did not present either. Mononuclear cells from G-BM from donors of patients who developed cGVHD showed a pro inflammatory response, characterized by an increased concentration of IL-17A (15.5 vs 0.71 pg/mL, p=0.013), TNF-α (80.27 vs 0.13 pg/mL, p=0.001), and IL-6 (4953.6 vs 11.75 pg/mL, p=0.025), after a mitogenic stimulation, compared to cells from donors of patients who did not developed GVHD. On the other hand, a decreased IL-10 production (2.62 vs 52.81 pg/mL, p=0.001) was documented in mononuclear cells from donors of patients who developed chronic GVHD, compared to donor cells of patients who did not. No significant difference in the production of IL-2, IL-4, and IFN-γ was observed. There was no difference in Th1 and Th2 between both groups, but mononuclear cells from donors of patients who developed chronic GVHD had a higher percentage of Th17 (1.02% vs 0.46%, p<0.001), and less Tregs (0.88% vs 1.95%, p<0.001), compared to those who did not developed GVHD. Conclusions Patients who develop cGVHD (29%) are characterized by a pro inflammatory response with an increased production of IL-17A, IL-6, and IFN-γ, and also a major percentage of Th17 cells. Also, a decreased suppressive response was documented with reduced IL-10 and Tregs levels. The low incidence of cGVHD show that G-CSF primed bone marrow is an excellent source for allogeneic HSC transplantations, and would be useful to compare these results with other HSC sources. Disclosures No relevant conflicts of interest to declare.

scholarly journals Eltrombopag maintains human hematopoietic stem and progenitor cells under inflammatory conditions mediated by IFN-γ

Blood ◽  
2019 ◽  
Vol 133 (19) ◽  
pp. 2043-2055 ◽  
Author(s):  
Luigi J. Alvarado ◽  
Heather D. Huntsman ◽  
Hai Cheng ◽  
Danielle M. Townsley ◽  
Thomas Winkler ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Binding Site ◽  
Bone Marrow Failure ◽  
Interferon Γ ◽  
General Mechanism ◽  
Clinical Activity ◽  
Critical Pathway ◽  
Hematopoietic Stem ◽  
Therapeutic Implications ◽  
Ifn Γ

Abstract The proinflammatory cytokine interferon-γ (IFN-γ) has been implicated in human hematopoietic stem and progenitor cell (HSPC) depletion in immune-mediated bone marrow failure syndromes. We show that IFN-γ specifically prevents full engagement of thrombopoietin (TPO), a primary positive regulator of HSPC survival, to its receptor (c-MPL) via steric occlusion of the low-affinity binding site, contributing to perturbation of TPO-induced signaling pathways and decreased survival of human HSPCs. Eltrombopag, a synthetic small molecule mimetic of TPO that interacts with c-MPL at a position distinct from the extracellular binding site of TPO, bypasses this inhibition, providing an explanation for its clinical activity in bone marrow failure, despite already elevated endogenous TPO levels. Thus, IFN-γ–mediated perturbation of TPO:c-MPL complex formation and the resulting inhibition of a critical pathway of growth factor cell signaling may represent a general mechanism by which IFN-γ impairs the function of human HSPCs. This understanding could have broad therapeutic implications for various disorders of chronic inflammation.

scholarly journals Enteral Immunization with Attenuated Recombinant Listeria monocytogenes as a Live Vaccine Vector: Organ-Dependent Dynamics of CD4 T Lymphocytes Reactive to a Leishmania major Tracer Epitope

2003 ◽  
Vol 71 (3) ◽  
pp. 1083-1090 ◽  
Author(s):  
Hélène Saklani-Jusforgues ◽  
Elisabeth Fontan ◽  
Neirouz Soussi ◽  
Geneviève Milon ◽  
Pierre L. Goossens
Keyword(s):  
T Cells ◽  
Listeria Monocytogenes ◽  
T Cell ◽  
Cd4 T Cells ◽  
Leishmania Major ◽  
Cd4 T Cell ◽  
Interleukin 4 ◽  
Cell Immune Response ◽  
Mesenteric Lymph Nodes ◽  
Ifn Γ

ABSTRACT Listeria monocytogenes is considered as a potential live bacterial vector, particularly for the induction of CD8 T cells. The CD4 T-cell immune response triggered after enteral immunization of mice has not yet been thoroughly characterized. The dynamics of gamma interferon (IFN-γ)- and interleukin-4 (IL-4)-secreting CD4 T cells were analyzed after priming through intragastric delivery of an attenuated ΔactA recombinant L. monocytogenes strain expressing the Leishmania major LACK protein; a peptide of this protein, LACK158-173 peptide (pLACK), is a well-characterized CD4 T-cell target in BALB/c mice. Five compartments were monitored: Peyer's patches, mesenteric lymph nodes (MLN), spleen, liver, and blood. A single intragastric inoculation of ΔactA-LACK-LM in BALB/c mice led to colonization of the MLN and spleen at a significant level for at least 3 days. Efficient priming of IFN-γ-secreting pLACK-reactive CD4 T cells was observed in all tested compartments. Interestingly, IL-4-secreting pLACK-reactive CD4 T cells were detectable at day 6 or 7 only in blood and liver. The absence of translocation of viable bacteria through the intestinal epithelium after further ΔactA-LACK-LM inoculations was concomitant with the absence of an increase in the level of IFN-γ secreted by the MLN, blood, and splenic pLACK-reactive Th1 T cells, although the levels remained significantly above the basal level. No change in this population size was detected in the spleen. However, an increase in the number of intragastric inoculations had a clinical beneficial effect in L. major-infected BALB/c mice. L. monocytogenes thus presents the potential of an efficient vector for induction of CD4 T cells when administered by the enteral route.

Effects of B7.2−/− Mature Dendritic Cells on Tolerance Induction to Alloantigens in Fetal Mice Following In Utero Transplantation with Lineage Depleted Bone Marrow.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 2134-2134
Author(s):  
Swati Bhattacharyya ◽  
Morton J. Cowan
Keyword(s):  
Bone Marrow ◽  
T Cells ◽  
Dendritic Cells ◽  
Stem Cell ◽  
In Utero ◽  
Relative Role ◽  
Skin Grafts ◽  
Hematopoietic Stem ◽  
Fetal Mice

Abstract In utero hematopoietic stem cell transplantation (IUT) has the potential to cure a variety of marrow stem cell defects without using marrow ablative therapy. However IUT for diseases other than SCID has been unsuccessful. To better understand the barriers to successful IUT we wanted to define the role of the B7.1/B7.2 co-stimulatory molecules in inducing tolerance to allogeneic donor bone marrow cells in the fetal murine recipient. We studied the relative role of B7.1 and B7.2 expression on dendritic cells (DC) on engraftment and in generating donor specific tolerance in fetal mice. Mature DC (mDC) from B7.1−/− or B7.2−/− donors and wild type (wt) lineage depleted (lin−) C57Bl/6 (B6) bone marrow (BM) were injected into gestational day (GD) 14 Balb/c fetuses. Recipients of lin− wt BM and B7.1−/− mDC had a significantly lower survival (47.4%, p<0.01) associated with mild-moderate GvHD compared to the recipients of B7.2−/− mDC and lin− BM (82.3%) where none developed GvHD. Engraftment results in blood at 6 weeks post IUT showed, B7.1−/− recipients had multilineage engraftment (4.7±0.8% T cells and 5.7± 1.1% granulocytes) in their blood, but by 12 weeks, only donor CD3+ (predominantly CD8+) cells (2.1±1.3%) were present. The percent H2Kb+ (donor) T cells (predominantly CD4+) in the blood of recipients of lin− wt BM and B7.2−/− was 11.8±8.5% at 6 weeks p<0.001 and 6.5±2.5% at 12 weeks, p=0.006. The circulating donor CD4+ cells were Th2 (CD4+CD25−IL4+IL10+) and Treg (CD4+CD25+IL4−IL10−). Both fractions inhibited the T cell proliferative response in the MLR. Long term engraftment in thymic tissues was found in the tolerant recipients of lin− wt BM and B7.2−/− mDC (13.4±8.3% donor CD3+ T cells). We also found prolonged (rejection by day 36) acceptance of donor skin grafts in 7 of 12 recipients of B7.2−/− mDC and 2 of 5 recipients of B7.2−/− mDC and lin−BM. All third party C3H grafts were rejected by day 14 and 80% of the Balb/c (self) skin grafts were permanently accepted. We hypothesized that tolerized animals would behave similarly to recipients of megadoses of syngeneic BM with an increase in multilineage engraftment. We injected a total of 200x106 male wt B6 lin− BM cells over 5 days into adult IUT recipients of B7.1−/− or B7.2−/− mDC ± lin− wt BM and wt age-matched allogeneic and syngeneic (female) controls. Mice that had received B7.2−/− mDC + lin− BM in utero showed multi-lineage engraftment in the blood. In contrast, the in utero recipients of B7.1−/− mDC + lin− BM showed no significant engraftment (p<0.05). In conclusion, donor DC costimulatory molecules significantly affect survival, engraftment and GvHD; and these responses to B7.2−/− mDC and lin− BM appear to be mediated by both Th2 and Treg donor cells.

Investigation of TCR-Vβ CDR3 Spectrotypes in CD4 and CD8 Lymphocytes from Paroxysmal Nocturnal Hemoglobinuria (PNH) Patients.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 2827-2827
Author(s):  
Akiko Nakamura ◽  
Tsutomu Shichishima ◽  
Hideyoshi Noji ◽  
Kazuhiko Ikeda ◽  
Yukio Maruyama
Keyword(s):  
Bone Marrow ◽  
Healthy Volunteer ◽  
Bone Marrow Failure ◽  
Interferon Γ ◽  
Relative Increase ◽  
Hematopoietic Stem ◽  
Bone Marrow Failure Syndromes ◽  
Abnormal Cells ◽  
Ifn Γ ◽  
Cd4 Lymphocytes

Abstract PNH is one disorder of bone marrow failure syndromes, including aplastic anemia and myelodysplastic syndrome. It is considered that immunologic mechanisms by cytotoxic T lymphocytes (CTLs) and interferon-γ (IFN-γ) contribute to hypoplastic bone marrow of these disorders. In addition, PNH is an acquired clonal disorder of the hematopoietic stem cell. Recently, it has been reported that analysis of T cell-antigen receptor (TCR)-Vβ repertoires, especially TCR-Vβ CDR3 (complementarity- determining region 3) spectrotypes, is an effective tool to study immunologic mechanisms by CTLs in pathophysiology of PNH (Karadimitris et al, Blood, 2000; Kook et al, Blood, 2002; Risitano et al, Blood, 2002). In the present study, we investigated 21 kinds of TCR-Vβ repertoires by flow cytometry in CD4 and CD8 lymphocytes from 5 PNH patients and a healthy volunteer and the TCR-Vβ CDR3 spectrotypes using polymerase chain reaction assay in CD4 and CD8 lymphocytes from 3 of 5 PNH patients and the control. We also quantitated intracellular IFN-γ in CD4 and CD8 lymphocytes from 5 PNH patients and the control according to the method by Sloand et al (Blood, 2002). We found no specific TCR-Vβ repertoires in CD4 and CD8 lymphocytes from PNH patients compared with the control. The TCR-Vβ repertoires with relative increase of CD4 or CD8 lymphocytes (over 10 of ratio of the proportion of each TCR-Vβ repertoire in a PNH patient/the proportion of the same TCR-Vβ repertoire in a healthy volunteer) were 13.6 or 4 and 22 in Case 1, 3 and 11 or 1 in Case 2, 3 and 13.6 or 3 in Case 3, 5.3 and 7.2 or 2, 3, 7, and 18 in Case 4, and 4, 5.2, 13.6, 16, and 23 or 1 and 14 in Case 5, respectively. TCR-Vβ CDR3 spectrotyping showed that in CD4 lymphocytes most CDR3 patterns were chiefly polyclonal, except for one oligoclonal (Case 1) and one monoclonal (Case 3) patterns of TCR-Vβ25; in CD8 lymphocytes most CDR3 consisted of polyclonal, oligoclonal, and/or monoclonal patterns, suggesting the possibility that CD8 lymphocytes recognize much more antigens of abnormal cells, probably including PNH clones, than CD4 lymphocytes. Unfortunately, we found the same patterns as described above in CD8 lymphocytes from the control, although CD4 lymphocytes from the control presented only polyclonal pattern of CDR3. Quantitative analyses of IFN-γ showed that index values of IFN-γ in CD4 and CD8 lymphocytes from PNH patients were higher than those from the control. However, we did not find any significant correlations between the spectrotypes of TCR-Vβ CDR3 and the index values of IFN-γ in PNH patients, suggesting that TCR-Vβ repertoires with monoclonal and oligoclonal CDR3 patterns do not necessarily produce much IFN-γ. In conclusion, our findings suggest that TCR-Vβ CDR3 spectrotyping is more effective tool to resolve some immune mechanisms of pathophysiology in PNH, especially by auto-reactive CTLs.

Prophylactic Amotosalen-Treated Donor T-Cells Prevent Late CMV Infection in Allogeneic Bone Marrow Transplantation.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 3024-3024
Author(s):  
Mohammad S. Hossain ◽  
John D. Robak ◽  
Edmund K. Waller
Keyword(s):  
Bone Marrow ◽  
T Cells ◽  
Viral Infection ◽  
Cd8 T Cells ◽  
Immune Reconstitution ◽  
Chronic Gvhd ◽  
Mcmv Infection ◽  
Tnf Α ◽  
Donor T Cells ◽  
Ifn Γ

Abstract A major problem in allogeneic BMT is post transplant immunodeficiency leading to opportunistic infection and relapse. Previously we showed that amotosalen-treated allogeneic donor T cells given at the time of BMT and experimental murine cytomegalovirus (MCMV) infection could prevent lethal MCMV disease without producing GvHD. In this study we have focused on a more clinically applicable model where prophylactic amotosalen-treated allogeneic donor splenocytes are given at the time of BMT, followed by MCMV infection 100 days later. We observed that amotosalen-treated donor T-cells significantly expanded and responded well in presence of viral infection without inducing any GvHD, protected recipients against viral disease, and were associated with significantly improved hematopoietic engraftment and immune reconstitution. Methods: Using a parent to F1 mouse BMT model, splenocytes (3x106 untreated or 10x106 amotosalen-treated) from MCMV immunized C57BL/6 donors were transplanted along with 5x106 T-cell depleted bone marrow (TCD BM) from naïve congeneic mice into lethally irradiated (11Gy) CB6F1 recipients (C57BL/6 x Balb/C). Recipient mice were infected i.p. with a sublethal dose (5x104 pfu per mouse) of MCMV 100 days or more after transplant. Clinical chronic GvHD was monitored by weight loss, hair loss, ruffled fur, diarrhea, and decreased activity. Flow cytometry was used to quantitate T cell chimerism (in recipient PBMC, spleen, liver and thymus) and MCMV-peptide specific CD8+ T-cells (tetramer+ and IFN-γ producing). Serum IFN-γ and TNF-α were determined by ELISA. Liver and spleen viral loads were determined by counting PFU in tissue homogenates plated onto 3T3 confluent monolayers. Results: Recipients of untreated control donor splenocytes suffered from chronic GvHD within 100 days of transplant, while those that received amotosalen-treated splenocytes experienced no GvHD. In response to MCMV infection at 100 days post transplant, residual amotosalen-treated donor T-cells rapidly expanded over 25-fold within 10 days, but did not cause lethality or detectable GvHD. Expanded amotosalen-treated T-cells showed activated anti-viral responses and developed a memory phenotype at late phases of viral infection. PBMC, spleen and liver showed elevated levels of MCMV specific tetramer+, IFN-γ+, and TNF-α+ CD8+ T-cells that were associated with accelerated viral clearance within day 3 after viral infection. While expansion and generation of amotosalen-treated donor T-cells mostly occurred in the liver, the generation of donor bone marrow-derived new T-cells occurred through both the thymus and the liver. In contrast, recipients of untreated donor splenocytes had reduced thymic function, resulting in severely impaired immune reconstitution and decreased anti-viral immunity. Conclusion: Prophylactically administered amotosalen-treated allogeneic donor T cells 1) were almost completely devoid of GvHD activity, 2) promoted hematopoietic engraftment and improved immune reconstitution, and 3) persisted long-term (&gt;100 days) and successfully protected recipients from sublethal MCMV infection. Thus, infusion of amotosalen-treated donor T-cells at the time of transplantation is a clinically-attractive approach to adoptive anti-viral immunotherapy without chronic GvHD following hematopoietic progenitor cell transplantation.

T-bet Over-Expression in T Cells from Patients with Aplastic Anemia.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 832-832
Author(s):  
Elena E. Solomou ◽  
Keyvan Keyvanfar ◽  
Elaine M. Sloand ◽  
Barbara Weinstein ◽  
Olga Nunez ◽  
...  
Keyword(s):  
T Cells ◽  
Stem Cell ◽  
Transcription Factors ◽  
Hematopoietic Stem ◽  
T Box ◽  
Protein Levels ◽  
Proximal Site ◽  
Ifn Γ ◽  
Bet Protein ◽  
Normal Controls

Abstract Acquired aplastic anemia (AA) is a bone marrow failure syndrome characterized by immune-mediated destruction of hematopoietic stem cells. T cells from patients with AA overproduce IFN-γ, a cytokine that inhibits hematopoietic stem cell proliferation and induces Fas-mediated apoptosis; stem cell depletion results in marrow hypoplasia and peripheral blood pancytopenia. In T cells, regulation of IFN-γ production occurs primarily at the level of transcription. A proximal site of the IFN-γ gene (−75 to −45bp of the IFN-γ promoter) is a binding site for different transcription factors including NFAT, AP-1, ATF, CREB, and T-bet. T-bet is a member of the T-box family of transcription factors, this family contains a highly conserved DNA binding domain, the T-box, that binds to a specific sequence in the promoter of different genes, including the IFN-γ promoter. T-bet is found in Th1 but not in Th2 cells and is the key regulator of Th1 development and function (Rengarajan et al., Immunol Today2000; 21: 479). The inducible expression of T-bet is mediated in part by Itk kinase (Sjabo et al., Science2005; 307: 430). In the present study, we examined T-bet protein levels in T cells from patients with AA. Samples from 17 of 20 patients examined (85%) by immunoblot showed increased T-bet protein levels in unstimulated T cells compared to normal controls (p = 0.0001). Normal controls showed undetectable T-bet protein levels in unstimulated T cells but T-bet expression was induced after 24 hrs of stimulation with PMA and ionomycin. In electrophoretical mobility shift assays, we observed increased T-bet binding to the proximal site of the IFN-γ promoter in T cells from patients with AA; no binding was detected in unstimulated T cells from healthy controls, but binding was present after stimulation for at least 24 hrs. T-bet protein levels correlated with disease activity. Patients with increased T-bet protein levels showed increased intracellular IFN-g levels compared to controls, as detected by flow cytometry (p&lt;0.05). Patients that expressed increased T-bet protein levels also showed increased levels of the Itk kinase (p=0.02). We examined if other kinases that lie downstream of Itk in the signal transduction activation cascade in T cells affected the inducible expression of T-bet. In normal T cells, rottlerin, a PKC-theta (PKC-𝛉) inhibitor, decreased T-bet protein levels by 50%; in AA T cells, rottlerin also decreased T-bet protein levels and IFN-γ intracellular levels by 50%. Our results suggest that the increased IFN-γ levels observed in AA are the result of activation of transcription of the IFN-γ gene by the regulator T-bet. Blocking of transcription of the IFN-γ gene by kinase inhibitors might represent a therapuetic strategy for AA and other human T cell-mediated autoimmune diseases.

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