scholarly journals Predictors of Efficacy in Chinese Patients with Severe Aplastic Anemia Treated with Eltrombopag and Intensive Immunosupressive Therapy

Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 1115-1115
Author(s):  
Ruixin Li ◽  
Guangsheng He ◽  
Xi Chen ◽  
Zhengyuan Liu ◽  
Yan Yang ◽  
...  
Keyword(s):  
T Cells ◽  
Aplastic Anemia ◽  
Roc Curve ◽  
Lymphocyte Count ◽  
East Asian ◽  
T Cell Subsets ◽  
Phase Iii ◽  
Chinese Patients ◽  
Autoreactive T Cells ◽  
Immunosupressive Therapy

Abstract Prospective trials showed the clinical efficacy of eltrombopag in refractory/relapsed aplastic anemia (AA), with up to 40% hematologic improvement [1]. Moreover, eltrombopag was combined with frontline immunosupressive therapy (IST) consisited of antithymocyte immunoglobulin (ATG) and cyclosporin (CsA), with an overall response rate exceeding 80% [2]. The metabolism of eltrodopag is different in disparate population. Currently, the recommended dose is 75 mg/d for East Asian populations [2], Pretreatment clinical and laboratory characteristics predicting eltrombopag response are still unclear in severe AA (SAA) patients of real-world in East Asian. From May 2014 to December 2020, 59 adult SAA patients were treated with IST (r-ATG, 3.5mg/kg/d × 5d and CsA 3-5 mg/kg/d) in conjunction with eltrodopag at the dose of 75 mg/d from day 1 until 6 months. We used Receiver Operating Characteristic (ROC) curve to predict the factors of the efficacy of eltrombopag. Median follow-up was 13 months (6 month to 29 months). Overall 45 patients (76%) responded to eltrombopag, including 16 patients (27%) who achieved complete response (CR) and 29 patients (49%) who achieved partial response (PR), whist 14 patients were non-remission (NR) according to the criteria of the European Group for Blood and Marrow Transplantation (EBMT) [3]. The severity (P=0.032), infection (P=0.039) and lymphocyte count (P=0.021), as well as reticulocyte percentage (P=0.002) were different significantly between groups before the treatment (Table 1). Yet, the median age (38 years and 50.5 years) and median time from diagnosis to treatment (16 d and 27.5 d) are comparable. There was no significant difference in the count of platelet and T cell subsets of peripheral blood. ROC curve was used as one model to predict factors linked to the effects of eltrodopag in 6 months. The lymphocyte count (P=0.042, AUC=0.721, 95%CI 0.537-0.904), the percentage of reticulocyte (P=0.007, AUC=0.793, 95%CI 0.631-0.955), and red cell distribution width - coefficient of variation (RDW-CV) (P=0.042, AUC=0.721, 95%CI 0.493-0.948) were positively correlated with the efficacy of eltrombopag (Table 2, Figure 1). Discussion It has been reported that moderate diseaseand lymphoid marrow infiltration were related with the response to eltrombopag in older AA patients [4]. Scheinberg et al. has showed that predictive factors related to IST of 6th month were including the age, lymphocyte count and reticulocyte count [5]. We found that the lymphocyte count, the percentage of reticulocytes and RDW-CV were related with response. The increase of RDW-CV is related to production of reticulocyte. A higher lymphocyte count, the percentage of reticulocytes and RDW-CV may indicate better residual marrow function. Lymphocyte count is also associated with abnormal immunity. Hematopoietic recovery of SAA depends on IST involving elimination of autoreactive T cells that target progenitor cells in the bone marrow, and sufficient residual stem cells to support blood cell production after IST. IST combined with eltrombopag could eradicate autoreactive T cells and promote hematopoiesis simultaneously, thereby, the relevant indicators for predicting efficacy also reflect this related status. This study was limited by its retrospective nature, small cohorts, an absence of randomization a treatment comparator, and IST was based on r-ATG and CsA. In preliminar conclusion, the pretreatment lymphocyte count, the percentage of reticulocytes and RDW-CV together serve as a simple predictor of response following IST combined with eltrombopag for Chinese patients with SAA. Reference [1] Olnes MJ, et al. Eltrombopag and improved hematopoiesis in refractory aplastic anemia. N Engl J Med. 2012;367(3):11-19. [2] Townsley DM, et al. Eltrombopag Added to Standard Immunosuppression for Aplastic Anemia [J]. N Engl J Med, 2017, 376 (16): 1540-1550. [3] de Latour, RP, et al. Results of the EBMT SAAWP Phase III Prospective Randomized Multicenter RACE Study of Horse ATG and Ciclosporin with or without Eltrombopag in naive SAA patients. EBMT 2020 abstract O018. [4] Fattizzo B, et al. Clinical and morphological predictors of outcome in older aplastic anemia patients treated with eltrombopag. Haematologica. 2019 Nov;104(11): e494-e496. [5] Scheinberg P,et al. Predicting response to immunosuppressive therapy and survival in severe aplastic anaemia. Br J Haematol. 2009 Jan;144(2):206-16. Figure 1 Figure 1. Disclosures No relevant conflicts of interest to declare.

scholarly journals Intensive Immunosupressive Therapy Combining with Eltrombopag for Adult Chinese Patients with Severe Aplastic Anemia

Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 2190-2190
Author(s):  
Ruixin Li ◽  
Yuanyuan Jin ◽  
Jinsong Jia ◽  
Shengyun Lin ◽  
Yan Yang ◽  
...  
Keyword(s):  
Multivariate Analysis ◽  
Adverse Events ◽  
Regression Model ◽  
Aplastic Anemia ◽  
Antithymocyte Globulin ◽  
T Cell Subsets ◽  
Phase Iii ◽  
Chinese Patients ◽  
Severe Aplastic Anemia ◽  
Significant Difference

Abstract In sight of different pharmacokinetics between races, the recommended dose is 75mg/d for Asian using eltrombopag [1]. However, the efficacy and safety of antithymocyte immunoglobulin (ATG) and cyclosporin A (CsA) with eltrombopag are still largely unknown for adult Asian patients with severe aplastic anemia (SAA). From May 2014 to March 2021, 121 Chinese adult patients with SAA were treated with IST (r-ATG, 3.5mg/kg/d × 5d and CsA 3-5 mg/kg/d) or in conjunction with eltrombopag (75mg/d, from day 1 to 6 months) prospectively and non-randomly. The adverse events (≥3 grades) referring to Common Terminology Criteria for Adverse Events version (CTCAE) 5.0 within 6 months. In pretreatment evaluation of clinical and laboratory characteristics. Median age (39 years and 40 years) was comparable. The complete blood count with differential and quantification of CD4/CD8 T-cell subsets were similar in both groups, but median time from diagnosis to treatment (16 d and 28 d, P=0.038) was different significantly (Table 1). The Chi-Squared test was used to compare the efficacy. The overall response rates (ORR) of IST alone or in combination with eltrombopag in the 1st, 3rd, 6th and 12th month after IST were 12% vs 35% (P=0.002), 44% vs 64% (P=0.028), 61% vs 85% (P=0.006) and 73% vs 91% (P=0.031), respectively. The complete response (CR) rates in the 3rd, 6th and 12th month after IST are 7% vs 17% (P=0.069), 14% vs 27% (P=0.11) and 33% vs 32% (P=0.92) (Table 2). We analyzed factors associated with the efficacy at 6 months by the Binary-Logistic regression model. Elements would be listed in multivariate analysis whether the factors might impact on the efficacy or had P value lower than 0.2 in univariate analysis. It was suggested that ORR was significantly related with the use of eltrombopag (P=0.011, OR=3.600, 95%CI 1.345-9.638) (Table 3). The overall survival (OS) and factors related to survival were analyzed by Kaplan-Meier method and Cox regression model. The OS in IST combined with eltrombopag group was 98% compared to 88% for IST alone (P=0.078). No significant intergroup differences were noted in multivariate analysis of OS. The nonhematologic adverse events (≥3 grades) were infrequent, occurring in 16% patients. 8 in IST plus E-PAG cohort and 11 in IST alone cohort (15% vs 16%, P=0.80). Hepatic injury was prevalent complication (6% vs 8%, P=0.96), relatively. But none showed significant difference between two groups. Discussion It has been reported that eltropopag promoted the response of megakaryocytic or even three lineages in refractory SAA [2]. The 6th month CR rate and ORR of our study are lower than the results of Townsley's research with 35% and 94% in the cohort of IST plus eltrombopag [1]. But the CR rate ORR is comparable to De Latour's results with 21.9% and 59.4% in the 3rd month [3]. Median age and dosage of eltrombopag needs to be considered with caution between different researchs, whist the efficacy of horse ATG (hATG) and rATG remained a subject of some debate [4]. Townsley et al. had reported that hepatic impairment (≥3 grades) was 18% [1], but our research showed lower rate of liver impairment with 6%. We should increase the sample volume to analyze the adverse events. Reference [1] Townsley DM, et al. Eltrombopag Added to Standard Immunosuppression for Aplastic Anemia [J]. N Engl J Med, 2017, 376 (16): 1540-1550. [2] Desmond R, et al. Eltrombopag restores trilineage hematopoiesis in refractory severe aplastic anemia that can be sustained on discontinuation of drug [J]. Blood, 2014, 123 (12): 1818-1825. [3] De Latour, RP, et al. Results of the EBMT SAAWP Phase III Prospective Randomized Multicenter RACE Study of Horse ATG and Ciclosporin with or without Eltrombopag in naive SAA patients. EBMT 2020 abstract O018. [4] Vallejo, C., et al., Rabbit antithymocyte globulin versus horse antithymocyte globulin for treatment of acquired aplastic anemia: a retrospective analysis. Annals of Hematology, 2015. 94(6): p. 947-954. Figure 1 Figure 1. Disclosures He: F. Hoffmann-La Roche Ltd.: Consultancy; LongBio Pharma: Consultancy, Research Funding.

scholarly journals Effect of dimethyl fumarate on lymphocyte subsets in patients with relapsing multiple sclerosis

2020 ◽  
Vol 6 (2) ◽  
pp. 205521732091861 ◽  
Author(s):  
Guy Buckle ◽  
Daniel Bandari ◽  
Jeffrey Greenstein ◽  
Mark Gudesblatt ◽  
Bhupendra Khatri ◽  
...  
Keyword(s):  
Multiple Sclerosis ◽  
T Cells ◽  
Confidence Interval ◽  
Cd8 T Cells ◽  
Lymphocyte Count ◽  
Absolute Lymphocyte Count ◽  
Dimethyl Fumarate ◽  
T Cell Subsets ◽  
Routine Practice ◽  
Patients At Risk

Background In patients treated with dimethyl fumarate, absolute lymphocyte count decline typically occurs during the first year and then plateaus; early drops have been associated with the development of severe prolonged lymphopenia. Objective We investigated the effect of dimethyl fumarate on absolute lymphocyte counts and CD4+/CD8+ T cells in patients with relapsing–remitting multiple sclerosis treated with dimethyl fumarate in routine practice. Methods Lymphocyte data were collected via medical chart abstraction. Primary endpoint: change from baseline in absolute lymphocyte count and CD4+/CD8+ counts at 6‐month intervals following dimethyl fumarate initiation. Results Charts of 483 patients were abstracted and 476 patients included in the analysis. Mean baseline absolute lymphocyte count (2.23 × 109/l) decreased by ∼39% (95% confidence interval: –41.1 to –37.2) by month 6 and 44% (95% confidence interval: –46.6 to –42.1) by month 12. CD4+ and CD8+ T-cell subsets strongly correlated with absolute lymphocyte count, with greater decreases from baseline to 6 months vs 6–12 months, and in CD8+ vs CD4+ T cells. Prior natalizumab was not a risk factor for lymphopenia. Conclusion Dimethyl fumarate-associated decline in absolute lymphocyte count in the first 12 months correlated with decline in CD4+ and CD8+ T cells and was independent of prior natalizumab. Absolute lymphocyte count monitoring continues to be an effective strategy to identify patients at risk of prolonged lymphopenia.

scholarly journals Functional characterization of CD4+ T cells in aplastic anemia

Blood ◽  
2012 ◽  
Vol 119 (9) ◽  
pp. 2033-2043 ◽  
Author(s):  
Shahram Kordasti ◽  
Judith Marsh ◽  
Sufyan Al-Khan ◽  
Jie Jiang ◽  
Alexander Smith ◽  
...  
Keyword(s):  
T Cells ◽  
Aplastic Anemia ◽  
Cd4 T Cells ◽  
High Throughput Sequencing ◽  
Functional Characterization ◽  
Effector T Cells ◽  
T Cell Subsets ◽  
Th2 Cells ◽  
Healthy Donors ◽  
Th1 And Th2

Abstract The role of CD4+ T cells in the pathogenesis of aplastic anemia (AA) is not well characterized. We investigate CD4+ T-cell subsets in AA. Sixty-three patients with acquired AA were studied. Th1 and Th2 cells were significantly higher in AA patients than in healthy donors (HDs; P = .03 and P = .006). Tregs were significantly lower in patients with severe AA than in HDs (P < .001) and patients with non-severe AA (P = .01). Th17 cells were increased in severe AA (P = .02) but normal in non-severe AA. Activated and resting Tregs were reduced in AA (P = .004; P = .01), whereas cytokine-secreting non-Tregs were increased (P = .003). Tregs from AA patients were unable to suppress normal effector T cells. In contrast, AA effector T cells were suppressible by Tregs from HDs. Th1 clonality in AA, investigated by high-throughput sequencing, was greater than in HDs (P = .03). Our results confirm that Th1 and Th2 cells are expanded and Tregs are functionally abnormal in AA. The clonally restricted expansion of Th1 cells is most likely to be antigen-driven, and induces an inflammatory environment, that exacerbate the functional impairment of Tregs, which are reduced in number.

scholarly journals Role of CMV-serostatus and CX3CR1 on lymphocyte kinetics and left ventricular remodelling in patients with acute myocardial infarction

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
L Spray ◽  
C Park ◽  
S Cormack ◽  
A Mohammad ◽  
P Panahi ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
T Cells ◽  
Lymphocyte Count ◽  
Microvascular Obstruction ◽  
Left Ventricular ◽  
Effector T Cells ◽  
T Cell Subsets ◽  
Cmv Status ◽  
Cx3cr1 Expression

Abstract Background Patients with latent cytomegalovirus (CMV) infection have higher rates of adverse cardiovascular outcomes, but the reasons for this remain elusive. CMV-induced changes to T-lymphocyte populations, with a proliferation of CMV-specific, CX3CR1+ effector memory cells, may contribute. Effector T-cells are associated with cardiovascular mortality in CMV positive patients, and ischaemia-reperfusion injury after ST-elevation myocardial infarction (STEMI) and primary percutaneous coronary intervention (pPCI). Purpose To investigate the effect of CMV status on lymphocyte kinetics and cardiac MRI (cMRI) parameters in 52 STEMI patients receiving pPCI, and examine the prognostic relevance of pre-reperfusion lymphocyte count in a large cohort. Methods We retrospectively analysed the association between pre-reperfusion lymphocyte count, troponin, and long-term survival in 4874 consecutive STEMI patients. Using flow cytometry, we analysed lymphocyte kinetics in 52 STEMI patients, of known CMV status, during and after pPCI. We assessed the impact of CMV status on infarct size, left-ventricular (LV) function and microvascular obstruction with cMRI in the first week after reperfusion in 101 patients. Repeat cMRI at 12 weeks, to assess LV remodelling, was obtained in 48 patients. Results Pre-reperfusion lymphopenia is an independent predictor of mortality over 7.5 years (hazard ratio for lowest vs highest quartile: 2.0; 95% CI 1.7–2.4; p&lt;0.001), and is associated with higher admission troponins (p&lt;0.001 for lowest vs second-lowest quartile), suggesting lymphocyte count falls prior to reperfusion in response to myocardial injury. CMV positive patients had more cytotoxic T-cells, strongly expressing the fractalkine receptor, CX3CR1. In CMV positive patients these cells fell dramatically by 90 minutes post-reperfusion, and dropped more sharply in patients with extensive microvascular obstruction on cMRI (p≤0.05 in all effector subsets). CX3CR1 expression was lower at 90 minutes post-reperfusion than at 24 hours (return to physiological expression) in all effector T-cell subsets. All subsets lost a similar proportion of their 24-hour value, but consistently lost a larger proportion in CMV positive patients (−27% in CMV+, −18% in CMV−; p=0.007). CX3CR1 expression falls in the presence of fractalkine, and we hypothesise that membrane-bound fractalkine is induced more strongly in CMV positive patients, as soluble fractalkine levels were similar. At 12 weeks, LV remodeling was worse in CMV positive patients (change in end-diastolic volume: +10.7ml vs −6.1ml; p=0.02). Conclusions Lymphopenia occurs prior to reperfusion in STEMI, and predicts long-term mortality. Effector T-cells drop substantially after reperfusion only in CMV positive patients, likely mediated by CX3CR1-fractalkine interaction, and this is associated with adverse cMRI findings. Remodeling is worse in CMV positive patients at 12 weeks post-STEMI. Lymphocytes, troponin and survival Funding Acknowledgement Type of funding source: Public Institution(s)

scholarly journals Hyperbaric Oxygen Therapy Alleviates the Autoimmune Encephalomyelitis via the Reduction of IL-17a and GM-Csf Production of Autoreactive T Cells as Well as Boosting the Immunosuppressive IL-10 in the Central Nervous System Tissue Lesions

Biomedicines ◽  
2021 ◽  
Vol 9 (8) ◽  
pp. 943
Author(s):  
Hsin-Ying Clair Chiou ◽  
Shu-Hung Huang ◽  
Chih-Hsing Hung ◽  
Su-Min Tsai ◽  
Hui-Ru Kuo ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Oxygen Therapy ◽  
T Cell Subsets ◽  
T Helper ◽  
Autoimmune Encephalomyelitis ◽  
Autoreactive T Cells ◽  
Gm Csf ◽  
The Central Nervous System ◽  
Cns Lesions

Multiple sclerosis (MS) is a chronic autoimmune disease mainly caused by autoreactive T cells, followed by neuronal demyelination and disabling paralysis. Hyperbaric oxygen therapy (HBOT) is usually an adjunct to therapy for the treatment of neurological disorders. However, it remains still controversial whether HBOT is an effective option for the treatment of MS. Experimental autoimmune encephalomyelitis (EAE) is a well-studied mouse model investigated for the MS pathogenesis and the efficacy of the therapeutic intervention. Both encephalitogenic Th1 and Th17 are pivotal T cell subsets immunopathogenically producing several disease-initiating/modifying cytokines in the central nervous system (CNS) lesions to further exacerbate/ameliorate the progression of EAE or MS. However, it remains unclear whether HBOT modulates the context of T helper cell subsets in CNS lesions. We employed EAE in the presence of HBOT to assess whether disease amelioration is attributed to alterations of CNS-infiltrating T cell subsets. Our results demonstrated that semi-therapeutic HBOT significantly alleviated the progression of EAE, at least, via the suppression of Th17 response, the downregulation of CD4 T helper cells expressing GM-CSF or TNF-α, and the boosting of immunomodulatory IL-4 or IL-10-expressed CD4 T cells in the CNS lesions. Conclusively, HBOT attenuated EAE through the modulation of T cell responses in an earlier stage.

scholarly journals Up-regulated Expression of Fas Antigen in Peripheral T cell Subsets in Patients with Myasthenia Gravis

2012 ◽  
Vol 35 (5) ◽  
pp. 294 ◽  
Author(s):  
Weihua Mai ◽  
Xingwei Liu ◽  
Yunping Fan ◽  
Hanwei Liu ◽  
Hai Yu Hong ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Myasthenia Gravis ◽  
Cd8 T Cells ◽  
Corticosteroid Treatment ◽  
T Cell Subsets ◽  
Chinese Patients ◽  
Fas Antigen ◽  
Significant Difference ◽  
Regulated Expression

Purpose: Recent reports have linked various autoimmune diseases to defective Fas-mediated apoptosis or Fas expression. Here we aimed to determine whether Fas-mediated apoptosis is involved in the pathogenesis of myasthenia gravis (MG). Methods: The expression of Fas antigen in peripheral T cell subsets from 17 Chinese patients with MG and 13 healthy individuals was determined by flow cytometry, and its associations with clinical classification, thymus pathology, the concomitance with hyperthyroidism (HT) and corticosteroid treatment were investigated. Results: Compared with normal controls, a significantly up-regulated expression of Fas antigen was observed in the peripheral CD4+, CD4+CD8- and CD4-CD8- T cell subsets from patients with MG. Fas expression in CD4-CD8+ T cells of MG patients with normal thymus was significantly higher than that of patients with thymoma. Fas expressions in CD4+CD8+ T cells in MG patients with HT was significantly higher than controls and the ones without HT. Enhanced Fas expressions was found in CD4-CD8+ and CD4-CD8- T cells of MG patients with corticosteroid treatment, but no significant difference of Fas expression in peripheral T cells between patients with ocular MG (OMG) and general MG (GMG) was observed. Conclusion: Fas antigen may play a role in the pathogenesis of MG. It may be involved in the mechanisms of corticosteroid treatment, and with the occurrence of HT. OMG may represent a systemic disease, similar to that of GMG.

Expansion of CD8+/perforin+ T-Cell Subset in Patients Predicts Response to Cyclosporin A Therapy in Patients with Erythroid Hypoplasia/Aplasia

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 1337-1337
Author(s):  
Hideaki Nitta ◽  
Yuka Harada ◽  
Hideo Hyodo ◽  
Akiro Kimura ◽  
Hironori Harada
Keyword(s):  
Bone Marrow ◽  
T Cells ◽  
T Cell ◽  
Cyclosporin A ◽  
Aplastic Anemia ◽  
Cell Subset ◽  
T Cell Subsets ◽  
Cell Subpopulation ◽  
T Cell Subset ◽  
Oligoclonal Expansion

Abstract Abstract 1337 Erythroid hypoplasia or aplasia is a hematological condition observed in including idiopathic pure red cell aplasia (PRCA), thymoma-associated PRCA and aplastic anemia. Myelodysplastic syndrome (MDS) with erythroid hypoplasia/aplasia in bone marrow is a rare type of MDS that was not included in existing classifications of MDS. Patients with erythroid hypoplasia/aplasia have common characteristics; transfusion dependencies, immunologic abnormalities and successful immunosuppressive therapies with cyclosporin A (CsA). Thus, we may regard erythroid hypoplasia/aplasia as one of hematological disease entities. However, pathogenic mechanisms of erythroid hypoplasia/aplasia have not been fully elucidated, although T-lymphocyte-mediated inhibition of erythropoiesis is suspected to be the most possible mechanism of the pathogenesis. Recently, we reported that oligoclonal expansion of CD8+/perforin+ T cells was observed in patients with thymoma-associated PRCA and the oligoclonality was exclusively detected in CD8+ T cells, but not CD4+ T cells. To clarify the pathogenetic role of the T-cells, we analyzed the T-cell subsets and therapeutic responses in patients with erythroid hypoplasia/aplasia in bone marrow. Among 253 patients with MDS diagnosed at Hiroshima University Hospital between 2000 and June 2011, 12 patients (4.7%) showed erythroid hypoplasia/aplasia. A total of 22 patients with erythroid hypoplasia/aplasia, including 8 MDS with erythroid hypoplasia/aplasia, 3 idiopathic PRCA, 3 thymoma-associated PRCA and 8 aplastic anemia, were enrolled in this study. All patients were treated with CsA and improvement in anemia in this study followed the International Working Group (IWG) 2006 criteria. For T-cell subset analysis, mononuclear cells (MNCs) were purified from bone marrow (BM) or peripheral blood (PB) of the patients. MNCs were stained with fluorescent (FITC, PE, PerCP or APC)-conjugated antibodies for CD8, perforin, CCR7, CD62L, CD27, CD28 and CD45RO, CD45RA and were subjected to flow cytometric analysis. As controls, 30 patients with MDS without erythroid hypoplasia/aplasia and 30 patients without BM abnormalities were also analyzed. Among 22 patients with erythroid hypoplasia/aplasia, 10 patients (4 MDS with erythroid hypoplasia/aplasia, 1 idiopathic PRCA, 3 thymoma-associated PRCA and 2 aplastic anemia) responded to CsA therapy within 2 to 8 weeks. The median blood hemoglobin concentration increased from 6.5 g/dL at the baseline to 9.3 g/dL with treatment, with a median increase of hemoglobin of 2.8 g/dL from the baseline. We attempted to compare the T-cell subsets between CsA-responders and non-responders. All of 3 thymoma-associated PRCA showed good response to CsA therapy, suggesting that the oligoclonal expansion of a CD8+/perforin+ T-cell subset may be associated with the responses to immunosuppressive therapy. Thus, we focused on a T-cell subpopulation expressing CD8+/perforin+. Intriguingly, the CD8+/perforin+ T cells were significantly increased in the CsA-responders (44.3 ± 9.6%, n=10) compared to the non-responders (19.0 ± 9.3%, n=12, P<0.0001), normal BM controls (16.9 ± 7.0%, n=30) and MDS without erythroid hypoplasia/aplasia (15.1 ± 7.0%, n=30). Among the CD8+/perforin+ T cells, CD27+/CD62L+/−/CCR7low/CD28low/CD45RA++/CD45RO+ population was prominent, which is consistent with an effector memory T (TEM) cell subset described by Decrion et al. Our study reveals that CD8+/perforin+ T cell subset is a large population in the patients with CsA-responsive erythroid hypoplasia/aplasia. It is suggested that CD8+/perforin+ T cell subset may have functions to reduce erythroid progenitors via immunological mechanisms. The mechanisms may be easily suppressed by immunosuppressive therapies. In conclusion, expansion of CD8+/perforin+ T cell subset predicts response to cyclosporin A therapy in patients with erythroid hypoplasia/aplasia. The disease entity of “erythroid hypoplasia/aplasia in bone marrow with expansion of CD8+/perforin+ T cell subset”, including MDS, PRCA with or without thymoma and aplastic anemia, may have common pathogenetic mechanisms. Disclosures: No relevant conflicts of interest to declare.

Well-characterized Mouse Model of Severe Aplastic Anemia Induced by Interferon-gamma in Combination with Busulphan: More Apoptotic CD4+CD25+ Regulatory T Cells

Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 4396-4396
Author(s):  
Zenghua Lin ◽  
Hong Liu ◽  
Han Wang
Keyword(s):  
T Cells ◽  
Regulatory T Cells ◽  
Mouse Model ◽  
Aplastic Anemia ◽  
Interferon Gamma ◽  
Peripheral Blood ◽  
T Cell Subsets ◽  
Severe Aplastic Anemia ◽  
Intragastric Administration ◽  
Ifn Γ

Abstract Abstract 4396 Aplastic anemia (AA) is defined as pancytopenia with a hypocellular marrow, and interferon-gamma (IFN-γ) plays a key role in the injury to stem and progenitor compartments in AA. In recent years, animal models of AA have helped us to strengthen understanding of the mechanisms causing AA. However, few well-characterized mouse models have been developed to study the pathogenesis of AA. We have first developed a novel mouse model of severe aplastic anemia (SAA) induced by administration with IFN-γ and busulphan. In this study, 60 clean-class 8-week-old BALB/c female mice were randomly selected to set up the SAA model using intraperitoneal injection with IFN-γ and intragastric administration with busulphan for 10 days (SAA group), the IFN-γ group (n=60), the busulphan group (n=60) and the un-treated group (n=60) were as control. A mortality of 20% was found in the SAA group at day 10 after treatment and increased to 100% at day 30 after treatment. All mice in SAA group developed the typical clinical and pathological patterns of SAA from day 10 post dosing. They presented bleedings in association with anemia and infections. The peripheral blood smear shows paucity of leukocytes, platelets and absolute reticulocytes with decreased hemoglobin concentration, lower compared with other groups (P<0.05, respectively). The same result also been found in spleen index and nucleated cells per tibia. The bone marrow smears and the patho-morphological examinations showed hypocellularity in marrow cell proliferation, while an increase in the number of fat cells, residual lymphocytosis, plasma cells, stromal elements. The depression was severe and irreversible with time. Furthermore, in order to confirm the immunological features of the novel mouse SAA model, the mononuclear cells of the peripheral blood and spleen were subjected to assess the percentage of Th1□ATh2□ATh17 and regulatory T cells in CD4+ T cell subsets by flow cytometry (FCM). In the SAA group, the FCM analysis showed increased frequencies of Th1 cells, Th17 cells, and ratio of Th1/Th2 with decreased frequencies of CD4+CD25+ regulatory T cells (Tregs) and CD4+CD25+FoxP3+ Tregs in peripheral blood and spleen (P<0.05, respectively). To further explore the mechanism of decreased frequencies of Tregs in SAA, after being pured by immunomagnetic beads, the splenic Tregs was subjected to assess the expression of Akt and transforming growth factor-β (TGF-β) using Western blot and the apoptosis of splenic Tregs was detected by FCM. Results showed that a greater proportion of apoptotic cells in splenic Tregs with down-expression of Akt and TGF-β was found in SAA group (P<0.05, respectively). Obviously, this improved mouse model of SAA induced by IFN-γ and busulphan closely duplicates human SAA in a short time and our findings may contribute to understanding the decreased number of Tregs characteristic of AA. Disclosures: No relevant conflicts of interest to declare.

Peripheral and tumor immune correlates in patients with advanced melanoma treated with combination nivolumab (anti-PD-1, BMS-936558, ONO-4538) and ipilimumab.

2013 ◽  
Vol 31 (15_suppl) ◽  
pp. 3003-3003 ◽  
Author(s):  
Margaret K. Callahan ◽  
Christine E. Horak ◽  
Michael A. Curran ◽  
Travis Hollman ◽  
David A. Schaer ◽  
...  
Keyword(s):  
T Cells ◽  
Combination Therapy ◽  
Objective Response ◽  
Predictive Biomarkers ◽  
Tumor Burden ◽  
T Cell Subsets ◽  
Phase Iii ◽  
Tumor Cell Membrane ◽  
Phenotypic Changes ◽  
Immune Correlates

3003^ Background: Nivolumab and ipilimumab are fully human monoclonal antibodies that block the immune checkpoint receptors PD-1 and CTLA-4, respectively. In a multi-cohort, phase I study of nivolumab/ipilimumab combination therapy in melanoma patients (pts), objective response rates up to 47% were observed (NCT01024231). Putative predictive biomarkers from peripheral blood (PB) or tumor, including tumor PD-L1 expression, absolute lymphocyte count (ALC) and PB myeloid derived suppressor cells (MDSC) were evaluated. Pharmacodynamic changes in activated and effector T cells were also assessed. Methods: Tumor PD-L1 membrane expression was assessed in archival FFPE specimens by immunohistochemistry (28-8 PD-L1 antibody). ALC was measured in serial PB samples; changes in the percentage, number and phenotype of activated CD4+ and CD8+T cells and MDSC were characterized by flow cytometry. Results: PD-L1 expression was seen in 37% (10/27) of pts, using a cut-off of 5% tumor cell membrane staining. Objective responses (OR) were seen in pts with both PD-L1 negative (8/17) and PD-L1 positive (4/10) tumors. Relative to baseline, a rise in ALC was not detected, but phenotypic changes in PB T-cell subsets, including increases in the percentage of CD4 and CD8 expressing HLA-DR, ICOS and/or Ki67 were seen with combination therapy. Low ALC (<1.0 at wk 6-7) did not preclude OR as 3 of 12 pts with low ALC responded. Of pts evaluated, OR with ≥80% reduction in tumor burden at 12 wk were seen in pts with a low frequency of pretreatment PB MDSC (3/7) but no OR were seen in pts with high MDSC (0/6). Conclusions: In this small subset of pts,OR were seen independent of PD-L1 or ALC status in contrast to prior observations with nivolumab or ipilimumab, respectively. Thus, the immune response generated by combination therapy may have unique features compared to either monotherapy. The relationship between frequency of PB MDSC and reduction in tumor burden will be further explored. Further efforts in this study and in future phase III randomized studies will investigate these and other phenotypic changes in immune cell populations and their relationship to patterns of clinical activity. Clinical trial information: NCT01024231.

scholarly journals Restoring Dysfunctional Bone Marrow Endothelial Cell Alleviates Aplastic Anemia

Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 202-202
Author(s):  
Shu-Qian Tang ◽  
Wei-Li Yao ◽  
Hong-Yan Zhao ◽  
Qi Wen ◽  
Yuan-Yuan Zhang ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Flow Cytometry ◽  
T Cells ◽  
Aplastic Anemia ◽  
T Cell Subsets ◽  
Positive Staining ◽  
Immunological Status ◽  
Ros Scavenger

Abstract Background Aplastic anemia (AA) is a life-threatening disease characterized by bone marrow (BM) failure and pancytopenia. Immunosuppressive therapy can rescue most patients with AA. However, the pathogenesis of AA is still not well elucidated and the new strategies need to be developed for AA patients. Increasing evidences suggested the dysfunctional BM microenvironment may be involved in the pathogenesis of AA. As important components of the BM microenvironment, endothelial cells (ECs) play a crucial role in supporting hematopoiesis and regulating immune. However, whether BM ECs are involved in the occurrence of AA and whether repairing BM ECs could improve the hematopoietic and immune status of AA patients remain to be elucidated. Aims To evaluate the quantity and function of BM ECs from AA patients. Moreover, to determine whether the dysfunctional BM ECs are involved in the occurrence of AA by affecting hematopoiesis and regulating immunity in vitro and in vivo. Finally, to uncover the therapeutic potential of repairing dysfunctional BM ECs to alter the hematopoietic and immunological status in AA patients. Methods This study enrolled 30 patients with AA and 30 healthy donors(HD). Flow cytometry and BM in situ immunofluorescence staining were used to analyze the proportion of ECs in BM of the two groups. The level of intracellular reactive oxygen species(ROS) and the proportion of apoptosis were detected by flow cytometry. The functions of BM ECs were evaluated by double-positive staining, migration and tube formation assays. To determine the effect of BM ECs on hematopoiesis and immunity, primary human BM ECs were separately cocultured with CD34 + and CD3 + cells. To further validate the role of BM ECs in the occurrence of AA, a classical AA mice model and VE-cadherin blocking antibody that could antagonize the function of BM ECs were used. Moreover, to explore potential approach of targeting the dysfunctional BM ECs, the exogenous EC infusion or N-acetyl-L-cysteine (NAC, a ROS scavenger) for repairing BM ECs were administrated to the AA mice. To further explore the repairing effect of NAC on BM ECs, the primary BM ECs from AA patients were treated by NAC in vitroand then the functions of BM ECs were evaluated. Results Compared with HD, BM ECs in AA patients were decreased and dysfunctional, which characterized by higher levels of ROS and apoptosis, impaired abilities of migration and angiogenesis. Furthermore, dysfunctional BM ECs from AA patients not only impaired their hematopoiesis-supporting ability but also promoted co-cultured T cells to polarize towards pro-inflammatory T cells in vitro, which resulted in an unbalanced T cell subsets. Consistently, AA mice demonstrated decreased BM ECs with increased level of intracellular ROS. Moreover, hematopoietic failure and immune imbalance in AA mice became more severe when the function of BM ECs was antagonized, whereas the administration of NAC or infusion of exogenous EC improved the hematopoietic and immunological status of AA mice via repairing BM ECs in vivo. In addition, we found the NAC treatment also restored the hematopoiesis-supporting ability and immunity-regulating ability of the primary ECs derived from AA patients in vitro. Summary/Conclusion Our study demonstrates for the first time that dysfunctional BM ECs with impaired hematopoiesis-supporting ability and abnormal immunomodulatory ability are involved in the pathogenesis of AA. Although further validation is required, restoring dysfunctional BM ECs via EC infusion or administration of ROS scavenger NAC might be a potential therapeutic approach for AA patients. Disclosures No relevant conflicts of interest to declare.

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