Comparison Of Lymphocytic Immune Profiles Of Aplastic Anemia and Hypocellular Myelodysplastic Syndrome

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 3719-3719
Author(s):  
Jeffrey J. Pu ◽  
Guillermo Rangel Rivera ◽  
Abigail Sido ◽  
Arthur Berg ◽  
Cinda Boyer ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Flow Cytometry ◽  
T Cells ◽  
Myelodysplastic Syndrome ◽  
Aplastic Anemia ◽  
Cell Population ◽  
Bone Marrow Failure ◽  
Expression Patterns ◽  
Lymphocyte Population ◽  
Cd19 Expression

Abstract Background Aplastic anemia (AA) and hypocellular myelodysplastic syndrome (MDS) are two common acquired bone marrow failure diseases. AA is mostly an acquired bone marrow disease caused by cellular and humoral mediated immune attack of hematopoietic stem cells (HSC) due to dysregulation of lymphocytic system, which leads to hematopoietic progenitor cell apoptosis and bone marrow failure. MDS is a group of heterogeneous acquired clonal HSC disorders with ineffective hematopoiesis. Approximately 10% to 20% of MDS manifests a reduced bone marrow cellularity, which comprises hypocellular MDS. There is increasing experimental and clinical indication that an immune-mediated damage to hematopoietic HSCs and changes in the hematopoiesis-supporting microenvironment contribute to the pathogenesis of hypocellular MDS. Because of the similarity of their bone marrow manifestation, hypocellular MDS and AA are often hard to distinguish. Mounting evidence indicates that abnormal activation of cytotoxic T cells plays a crucial role in the pathophysiology of these diseases. One study showed that AA patients have an abnormally activated subpopulation of CD4+ helper cells and a decreased number and function of T regulatory cells in the bone marrow. GVHD mouse models further demonstrated that self-reactive T cells were capable of recognizing non-polymorphic tissue or commensally-derived antigens. Recent literature suggests that immune dysregulation plays a major role in pathogenesis of acquired bone marrow failure disease. However immune profiles of these two diseases have not been thoroughly studied, specially the role of B lymphocyte population. Our study aims to find lymphocytic surface marker expression patterns of hypocellular MDS and AA in both immature cell and lymphocyte populations. Methods This retrospective study analyzed flow cytometry lymphocytic antigen expression profiles from patients diagnosed as AA and hypocellular MDS as per standard criteria. A total of 31 AA and 26 hypocellular MDS patient cases were recruited. The bone marrow aspirate/biopsy data, bone marrow aspiration flow cytometry reports, and Complete Blood Counts (CBC)s from individual patients were analyzed. Using side scatter (SSC) vs. CD45 gating flow cytometry panels, we identified immature cell population (SSClow/CD45low) and lymphocyte population (SSClow/CD45high). We then quantitatively analyzed the expression patterns of 33 cluster differentiation (CD) molecules on individual sample. Finally, we compared the CD expression patterns between AA and hypocellular MDS in both cell populations respectively. Results CD19 expression was significantly higher in AA than in hypocellular MDS in both SSClow/CD45low cell population (P=0.001) and SSClow/CD45high cell population (P=0.003). Hypocellular MDS contains significantly higher CD34high cells than AA in SSClow/CD45low populations (mean:28.5% vs 8.5%; range; 1% to 94% vs 2% to 27%; P=0.04). However, patients with both diseases similarly contains very few CD34high cells in SSClow/CD45high cell population (mean: 0.6% vs 2.6%; range: 0.0% to 2% vs 0.0% to 32%; P=0.99). Conclusion 1. In AA, B cells are highly proliferative in both immature stage and mature stage. This data indicates that B cells which may play a unique role in AA pathogenesis but not in hypocellular MDS. 2. In both AA and hypocellular MDS, the majority of lymphocyte population are mature cells. This data suggests that the pathogeneses of both diseases caused by a persistently dysregulated immune microenvironment, not by an acute insult. CD19 expression pattern may be a useful marker to distinguish AA and hypocellular MDS. Disclosures: No relevant conflicts of interest to declare.

scholarly journals STAT3 mutations indicate the presence of subclinical T-cell clones in a subset of aplastic anemia and myelodysplastic syndrome patients

Blood ◽  
2013 ◽  
Vol 122 (14) ◽  
pp. 2453-2459 ◽  
Author(s):  
Andres Jerez ◽  
Michael J. Clemente ◽  
Hideki Makishima ◽  
Hanna Rajala ◽  
Ines Gómez-Seguí ◽  
...  
Keyword(s):  
Bone Marrow ◽  
T Cells ◽  
T Cell ◽  
Myelodysplastic Syndrome ◽  
Aplastic Anemia ◽  
Somatic Mutation ◽  
Bone Marrow Failure ◽  
Cell Clones ◽  
Key Points ◽  
Stat3 Mutations

Key PointsSTAT3+ T cells are found not only in detected concomitant LGL-BMFs, but in cases in which an LGL expansion was not suspected. Transformation via acquisition of a somatic mutation in T cells may be a mechanism of immune, mainly hypoplastic, bone marrow failure.

Decreased Numbers of Tregs in Aplastic Anemia Is Detected by Immunohistochemistry and Flow Cytometry.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 1703-1703
Author(s):  
Bianca Serio ◽  
Ziad Peerwani ◽  
Ramon Tiu ◽  
Jennifer Powers ◽  
Erik Hsi ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Flow Cytometry ◽  
T Cells ◽  
Aplastic Anemia ◽  
Immunohistochemical Staining ◽  
Bone Marrow Failure ◽  
Peripheral Tolerance ◽  
Hematopoietic Stem ◽  
Central Tolerance ◽  
Immune Mediated

Abstract Idiopathic aplastic anemia (AA) is characterized by immune-mediated destruction of hematopoietic stem cells, leading to peripheral pancytopenia. Immune pathogenesis in AA is supported by experimental data, as well as clinical observations and may be related to the breach of peripheral or central tolerance. Regulatory T cells (Treg) constitute one of the most important mechanisms of central tolerance engaged in the down-modulation of autoreactive T cells. Tregs have been found to be reduced in several autoimmune diseases and decreased frequencies of Tregs were also reported in AA and MDS. Overexpression of the high affinity IL-2 receptor alpha chain (CD25) and the forkhead family transcription factor P3 (FoxP3), required for the development and function of Tregs, serve as phenotypic markers for Tregs. We investigated Treg levels in a cohort of AA patients (N=21) and healthy individuals (N=15); flow cytometric quantification of Treg was carried out after surface/intracellular staining of whole blood for Treg markers (CD3, CD4, CD25, FoxP3). After proper gating (light scatter properties, CD3, CD4, CD25), CD4+ T cells were subdivided into CD25−, CD25int and CD25hi populations, and the co-expression of CD25hi and Foxp3 was analyzed. In comparison to controls, AA patients (N=12) show not only lower frequencies of CD4+CD25hi+ T cells within the total lymphocyte population (median 0.07% vs. 0.21%; p=.03), but also absolute lower absolute numbers (1.31/uL vs. 5.78/uL, p=.0002). Similarly, CD4+CD25hi+FoxP3+ T cells were found to be depressed in untreated AA patients in comparison to controls (median 0.07% vs. 0.21% and 1.06/uL vs. 4.76/uL; p=.03 and p=.003). While Tregs were lower in patients with active disease unresponsive to immunosuppressive treatment (responder 0.1% vs non responder 0.07%, CD4+CD25hi Tcells, p=.02), serial testing performed in 6 patients treated with ATG/CsA did not reveal correlation between hematologic improvement and recovery of Treg numbers. When double immunohistochemical staining for CD3 and Foxp3 was performed in pre-treatment bone marrow core biopsies of AA patients (N=3) and controls (N=2) a mean of 3 CD3+Foxp3+ cells/10 high power fields (hpf) were counted (vs. mean 28/10 hpf, p<.05 in controls), suggesting that lower numbers of Tregs were also present in the bone marrow of AA patients. In conclusion, our results suggest that Tregs are decreased in blood and marrow of patients with idiopathic AA, consistent with the breach of peripheral tolerance in AA. In addition to flow cytometry, immunohistochemical staining of histologic specimens can be used for the quantitative analysis of Tregs in bone marrow failure syndromes and other immune-mediated conditions such as GvHD.

SAP (SH2D1A), the Immunomodulator Deficient in X-Linked Lymphoproliferative Syndrome (XLP), Is Profoundly Decreased in Aplastic Anemia: An Immunologic Link between Constitutional and Acquired Bone Marrow Failure.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 1141-1141
Author(s):  
Elena E. Solomou ◽  
Valeria Visconte ◽  
Federica Gibellini ◽  
Neal S. Young
Keyword(s):  
Bone Marrow ◽  
T Cells ◽  
T Cell ◽  
Aplastic Anemia ◽  
T Cell Activation ◽  
Cell Activation ◽  
Bone Marrow Failure ◽  
Protein Levels ◽  
Ifn Γ ◽  
Th1 Polarization

Abstract Ligation of the signaling lymphocyte activation molecule (SLAM), a member of the immunoglobulin superfamily expressed in T and B cells, results in T cell activation and Th1 cytokine production. SAP is a small cytoplasmic protein expressed in T- and NK cells that controls the activation signals mediated by SLAM. On T cell activation, SAP binds to Fyn kinase; Fyn is activated and phosphorylates tyrosine residues on SLAM; phosphorylation results in the formation of a complex that selectively down-regulates co-stimulatory signals in activated T cells, resulting in inhibition of IFN-γ production. Thus SAP acts as a natural suppressor of SLAM-mediated T cell activation, and, in the absence of SAP, T cells are constitutively activated and overproduce IFN-γ. Mutations in the SAP gene lead to abnormal T cell activation and enhanced Th1 cytokine production in mouse models and in humans: about half of patients with X-linked lympoproliferative disease (XLP) have functionally disabling SAP mutations. Acquired aplastic anemia (AA) is a bone marrow failure syndrome in which hematopoietic cell destruction is effected by cytotoxic T cells and type 1 cytokines. We have recently shown that T cells from patients with AA have increased protein levels of T-bet, resulting in IFN-γ overproduction (Solomou EE et al, Blood2006; 107:3983). IFN-γ inhibits hematopoietic stem cell proliferation and induces Fas-mediated apoptosis; stem cell depletion results in marrow hypoplasia and peripheral blood pancytopenia. We examined SAP expression as an explanation for aberrant T cell activation and extreme Th1 polarization. SAP protein expression on immunoblot was very low to absent in unstimulated T cells from 16 of 20 AA patients examined, as compared to normal levels of expression in equivalent numbers of healthy donors (p<0.001). No significant differences were detected in Fyn and SLAM protein levels between AA and controls. SAP mRNA levels were also significantly decreased in T cells from those AA patients with low SAP protein levels, as determined by RT-PCR. Peripheral blood DNA samples from 18 patients with AA were analyzed for SAP mutations: three novel intronic mutations, not present in controls, were identified among 7 unrelated patients: one mutation was in the promoter region of SAP (position 106, C to T; 3 patients), and two mutations in the intron-exon junction between exons 1 and 2 (position 38975, C toT; 3 patients) and 3 and 4 (position 62771, C to A; 1 patient). IFN-γ, as measured by ELISA, in three patients with undetectable SAP protein levels was significantly increased compared to healthy controls (n=5, p<0.001). Increased IFN-γ levels and Th1 polarization in AA can in part be explained by functional SAP deficiency. SAP-deficient T cells in AA would be unable to block co-stimulatory signals, leading to an activated T cell phenotype and ultimately hematopoietic cell destruction and bone marrow failure. The SAP-deficient phenotype in T cells from patients with aplastic anemia may be secondary to subtle genetic alteration in the gene’s regulation (abnormal promoter binding sites or epigenetic modulation due to mutations in introns) or as yet unidentified aberrant upstream pathways (Ets-1 and Ets-2, the transcription factors that regulate SAP expression).

Study on Mechanism of Human Marrow Mesenchymal Stem Cell in Treating Patients with Aplastic Anemia.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 4099-4099
Author(s):  
Zhenhua Qiao ◽  
Xiujuan Zhao
Keyword(s):  
Bone Marrow ◽  
Flow Cytometry ◽  
T Cells ◽  
Aplastic Anemia ◽  
Hematopoietic Cell ◽  
Control Group ◽  
Rt Pcr ◽  
Tnf Α ◽  
Ifn Γ ◽  
Tgf Β1

Abstract Objective: To explore mechanism of human marrow mesenchymal stem cells (MSCs) in treating patients with aplastic anemia(AA). Methods: MSCs in patients with aplastic anemia(AA) and the control group were separated with Percoll(1.073g/m L) and cultured in low glucose DMEM. Then, observed their morphologies,checked their molecule surface antigen by flow cytometry and examined the process of adipogenic differention. The mononuclear cells (MNC)of marrow in patients with AA were enriched based 1.077g/L density centrifuge and cultured in the 1640 medium. (1)MSC in control group and MNC in AA group were co-cultured with or without cytokines. The function of supporting hematopoiesis for MSC was to be observed in single confluence layer after plating by counting the total cells and the clones in every well every week. Then analyzed the dynamics of proliferation. T cells were harvested by using nylon column. MSC in control group and T cells in AA group were co-cultured. The proliferation of T cell was measured by MTT method. The CD25,CD69,CD4,CD8,Annexin-V expression rates of CD3+T cells were analyzed by flow cytometry .The gene and protein of IL-2, IL-4,IL-10,TNF-α,IFN-γ,TGF-β1 were examined by RT-PCR and ELISA respectively. MSC treated to the model of AA, by the examination of peripheral hemogram, bone marrow biopsy, pathological section of spleen. Results: There was no significant difference between control group MSC and AA-MSC in morphologies but adipogenic differentiation in AA patients is earlier than controls. The clones of CFU-GM in group(MSC)(78.46±3.58)/2×105 cells, after 14 days cultured was significantly higher than(9.21±4.32)/2×105 cells in group(CK + DMEM medium), while lower than (99.32±4.34)/2×105 cells in group(MSC+CK). (1)the Treg cells (TCD4+CD25+) in AA group (2.01±1.21)/ 2×105 was significantly lower than (4.43±1.67)/2×105 cells in control group, while(5.43±2.31) / 2×105 in group (MSC+AAT) was no more than (4.43±1.67)/2×105 cells in control group. (2) MSCs significantly inhibited T cell proliferation (P< 0. O5)by MTT. (3) RT-PCR and ELISA analysis showed that MSCs induced the expression of IL-4, IL-10, TGF-β1 and decreased significantly the expression of IL-2, TNF-α, IFN -γ in T cells of AA. the model of AA treated by MSCs showed improvements in 3 blood components greatly(p<0.05), Bone marrow proliferated and restored to the normal level, hematopoietic cell increased obviously (hematopoietic cell capacity was more than 40%), and atrophied spleen restore to normality. Conclusions: morphologies of AA’MSC had no evident different with the control but was more easy adipogenic differention. aplastic anemia belongs to autoimmune diseases in which T cells effect organ-specific destruction. The fundamental mechanism of MSC in treating AA should be potential to promote hematopoietic cell proliferation by adjusting immunity.

Usefulness of Unicel DxH 800 Cell Population Data in the Detection of Plasmacell Leukemia: 2 Cases Report

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 4915-4915
Author(s):  
Donatella Raspadori ◽  
Santina Sirianni ◽  
Alessandro Gozzetti ◽  
Francesco Lauria ◽  
Claudio Fogli ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Flow Cytometry ◽  
Cell Population ◽  
Blood Smear ◽  
Normal Values ◽  
Population Data ◽  
Morphological Features ◽  
Short Report ◽  
Lymphocyte Population ◽  
Literature Report

Abstract Abstract 4915 Introduction and methods. Lymphoproliferative disorders (LD) are characterized and described by lymphocyte population with heterogeneous morphological features both in optical microscopy revision and in flow cytometry. Several literature report the clinical usefulness of Cell Population Data (CPD) provided by Beckman Coulter hematology analyzers. Abnormal values of CPD correlate with morphological abnormalities of leukocytes. In this work we present a case report of a plasmacell leukemia analyzed with UniCel DxH800 device. DxH800 performs leukocytes differential with the Flow Cytometric Digital Morphology (FCDM) technology, based on the measurements of Volume (V), Conductivity (C) and 5-angle Scatter light laser (MALS, UMALS, LMALS, LALS, AL2) on cells in their native state. Mean and standard deviation of FCDM measurements are collected in 56 CPD. Normal CPD values were computed from a 42 normal samples. Results. A 47-years old woman, referring continuous asthenia, was addressed to our lab with clinical suspect of LD with leukocytosis (WBC=17190/μl, LY#=3800). DxH800 analysis confirmed WBC count adding some important comments. WBC histogram showed a big peak in lymphocyte population. Differential values reported neutrophilia and lymphocytosis while scatterplot showed a lymphocyte cluster very close to the neutrophil one. CPD suggested a heterogeneous neutrophil population with low volume and low scatters (MALS, UMALS, LMALS, LALS, AL2 in arbitrary units) respectively of 106, 90, 112, 62, 75 vs normal values of 144, 137, 143, 158, 159. Examination of blood smear showed a lot of lymphocyte with nuclear immaturity and plasmoblast features. Immunophenotype revealed that 63% of the WBC were CD138+/CD38+, CD56+ CD200-, CD27- CD20-. Bone marrow biopsy confirmed the plasmacell leukemia diagnosis. A 65-years old man was admitted to our department for a light lymphocytosis associated with a IgGk monoclonal component. Immunophenotipic analysis showed a NK proliferation (CD3 50%, CD4 38%, CD8 34%, CD2 92%, CD7 92%, CD16 45%, CD56 48%, CD57 54%). DxH800 analysis reported LY#=3.6/μl and MO#=1,6/μl. LY CPD indicate cells with light signals of degranulation (MALS=56, UMALS=60, LMALS=63 vs normal values of 66, 60 and 63 ) together with abnormal monocyte CPD such as MV=157, MC=136, MALS=79, UMALS=80, LALS=75 vs normal values of 164, 129, 85, 80 and 75 respectively. All this data induced us to look for a mononuclear population different both from lymphocytes and monocytes in the peripheral blood smear. Bone marrow microscopy analysis showed morphologically abnormal cells that were classified as plasmacells after immunophenotyping (CD138+/CD38+, CD56+, CD45-, CD117+, CD20-, CD27-, CD200+. Further immunophenotypic analysis showed in PB 14% of plasmacells CD138+/CD38+/CD45-. Conclusion. We presented 2 cases report of a plasmacell leukemia whose diagnosis were supported by the useful information of the CPD provided by DxH 800. CPD abnormal values for lymphocytes and monocytes were known to correlate with morphological abnormalites of the cells. For this reason we were triggered to deeply investigate the blood smear of the two patient and we performed the immunophenotyping. This short report confirm the usefulness of CPD provided by UniCel DxH800 as the first check point for the diagnostic route. Moreover we confirm that morphological features in the PB smear discovered during the diagnosis, supported by flow-cytometry data, were properly correlated with CPD values. Disclosures: Fogli: Instrumentation Laboratory: Employment. Di Gaetano:Instrumentation Laboratory: Employment.

Intravenous Immunoglobulin Is an Effective Treatment for LGL-Mediated Immune Cytopenias in Myelodysplastic Syndromes and Other Bone Marrow Failure Syndromes

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 1704-1704
Author(s):  
Francesca Schieppati ◽  
Erin P. Demakos ◽  
Odchimar Rosalie-Reissig ◽  
Shyamala C. Navada ◽  
Lewis R. Silverman
Keyword(s):  
Bone Marrow ◽  
Myelodysplastic Syndrome ◽  
Aplastic Anemia ◽  
Intravenous Immunoglobulin ◽  
Hemolytic Anemia ◽  
Bone Marrow Failure ◽  
Myeloproliferative Neoplasm ◽  
Recurrent Fever

Abstract Background: Myelodysplastic Syndrome (MDS) and Aplastic Anemia (AA) are often associated with clinical immune manifestations. An abnormal profile of the T-cell repertoire can be detected in these patients (pts) and is thought to play a role in bone marrow (BM) insufficiency. The presence of a co-existent large granular lymphocytic (LGL) clone may exacerbate cytopenias independent of the primary disease mechanism and offers another target for therapeutic intervention. Treatment for LGL proliferation is usually immunosuppressive therapy but there is no accepted standard of care. Methods: We explored the role of intravenous immunoglobulin (IVIG) as a treatment for immune-related cytopenias, i.e. Coombs negative (C-) hemolytic anemia, in a series of 12 consecutive pts with an LGL clonal proliferation documented by flow cytometry and TCR clonal rearrangements. Of the 12 cases, 9 had MDS (7 lower-risk), 1 AA with LGL liver involvement, and 1 primary myelofibrosis. One patient (pt) had suspected MDS. Overall response was assessed by MDS IWG criteria 2006. We defined a hemolysis response (HLR) as complete normalization (CR) or, a greater than 50% improvement (PR) in deviation from normal values of LDH, reticulocytes, indirect bilirubin and haptoglobin. Duration of HLR was defined as the time from onset of HLR to the time of resumption of hemolysis and loss of effect of IVIG. Results: All pts were treated with IVIG administered at a dose of 500mg/kg of IVIG once per week, in repeated cycles, with a duration ranging from 1-4 week(s) per cycle. Clinical characteristics (Table 1): M/F ratio 10/2; median age 69. Ten pts had a CD3+ T-LGL and 2 had a CD3-/CD16+/CD56+ NK-LGL circulating clone. Karyotype abnormalities were non-specific; 8 pts had 1-3+ reticulin BM fibrosis; 4 had mutations in RNA-splicing genes: SF3B1 (2); SETBP1 (1); SRSF2 (1). Ten pts were evaluable for response: 8 pts responded (ORR 80%): Hematological improvement (HI-erythroid) 8/8 (100%); a hemolysis CR (HLR-CR) occurred in 7 (87.5%) and hemolysis PR (HLR-PR) in 1 pt (12.5%). Median number of cycles, follow up, and duration of treatment were 16, 21.5 and 9.5 months (mo), respectively. The HLR-CR was durable and prolonged in 3/8 (38%) pts; 2 of these 3 pts (67%) did not require maintenance IVIG. Relapse from HLR occurred in 4, during infection or chemotherapy, but the response returned to the original level by shortening the intervals between administration of IVIG. One pt had relapsed after an initial response and then became refractory to IVIG. In follow up at month 38, 75% of pts were still responding to treatment, and 1 pt was still in remission after 46 mo. In 4 of 6 pts, corticosteroid treatment was discontinued and no longer required for chronic hemolysis, with general improvement of steroid related symptoms. Some patients had been on steroids maintenance for periods ranging from months to years. Response was more durable with continuous rather than sporadic dosing. Adverse events were not specific: 1 pt with self-limited isolated palpitations; 1 pt with hypertension not requiring intervention. Conclusions: Treatment with IVIG of immune cytopenias associated with LGL clones and BMF yields durable responses in 80% of pts. IVIG, especially at high concentrations, may enhance apoptosis, suppress proliferation of T-cells and induce immune-regulation. Given the relative rarity of LGL clones in MDS, further investigational studies will help define the role of IVIG and clarify the mechanism of action in this group of pts with MDS and BMF associated with LGL clones. Table 1. Variable Observed % Symptomatic anemia (fatigue, SOB) 9/12 75 B symptoms (recurrent fever) 2/12 16.6 Infections (bacteremia Campylobacter with migratory arthritis and dermatitis; cellulitis bacteremia S. epidermidis and osteomyelitis) 2/12 16.6 Skin lesions (leg focal ulceration and dermal fibrosis) 1/12 8.3 Splenomegaly 7/12 58.3 Hepatomegaly 2/12 16.6 Adenopathy (mediastinal) 1/12 8.3 Neuropathy 2/12 16.6 Hematologic disorders 11/12 91.6 Myelodysplastic syndrome 9/12 75 Severe aplastic anemia 1/12 8.3 Myeloproliferative neoplasm (PMF) 1/12 8.3 Lymphoproliferative neoplasm (FL+MDS) 1/12 8.3 Hemolytic anemia 11/12 91.6 Solid tumors (anal, squamous cell; breast ca) 2/12 16.6 Autoimmune disorders 7/12 58.3 ITP 3/7 42.8 Ulcerative colitis 1/7 14.3 Pernicious anemia 1/7 14.3 Systemic lupus erythematosus 1/7 14.3 Immune pancreatitis 1/7 14.3 MGUS 4/12 33.3 Disclosures Off Label Use: IVIG.

scholarly journals Oligoclonal Expansion and T-Cells Subpopulations in Patients with Aplastic Anemia at Different Stages of the Disease

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 3864-3864
Author(s):  
Anastasia V. Abramova ◽  
Elena A. Mikhaylova ◽  
Zalina T. Fidarova ◽  
Yuliya O. Davydova ◽  
Nikolay M. Kapranov ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Flow Cytometry ◽  
T Cells ◽  
T Cell ◽  
Aplastic Anemia ◽  
Memory T Cells ◽  
Clonal Expansion ◽  
Th Cells ◽  
Healthy Donors ◽  
Oligoclonal Expansion

Abstract Background. The main mechanism of the bone marrow (BM) failure in idiopathic aplastic anemia (AA) has an immunomediated character. Researching the T-cell clone's effect in the AA pathogenesis is very relevant at the present time. Oligoclonal expansion of T cells is frequent in AA and the identification of immunodominant T-cell clones can correlate with the disease activity and may possibly serve as response predictor to immunosuppressive therapy (IST). The aim. To identify T-cells subpopulations, expression of PD-1 and PD-L1 on T-cells and TCR-Vβ repertoires by flow cytometry in different groups of AA patients. Methods. Thirty AA patients (pts) with median age of 30.5 (19-71), m/f ratio 1:1,3 were divided in 3 groups: pts with newly diagnosed (ND) AA (n=13), pts with overall response to IST (OR) (n=10), non-response pts (NR) for 2 and more lines of IST (n=7). Flow cytometry was performed with BD FACS Canto II. We used commercial kit (IOTest® Beta Mark TCR Vb Repertoire) for evaluation of TCR-Vβ repertoire in the bone marrow (BM) of these patients. We performed analysis of BM samples from healthy donors as a control group (n=8). Due to low amount of donor samples the maximal value each of the 24 subclones (for CD4+ (T-helpers - Th) and CD8+ cells (T-cytotoxic cells - TCL)) was accepted as threshold. We concluded the presence of clonal expansion if TCR subclone exceeded this threshold. We identified different T-cell subpopulations in all 3 groups of AA and healthy donors by flow cytometry: double positive T-cells (CD3+CD4+CD8+), double negative T-cells (CD3+CD4- CD8-), Th (CD3+CD4+), TCL (CD3+CD8+), NK-T-cells (CD3+CD56+) out of CD3+ cells. Among Th and TCL cells was determined naive T-cells (CD28+CD95-), effector T-cells (CD28-CD95+), memory T-cells (CD28+CD95+), regulatory T-cells (CD4+CD127-CD25high) and subpopulations Th and TCL co-expressed PD-1 and PD-L1. Multiple comparisons were assessed by ANOVA or Kruskal Wallis test by GraphPad Prism software. Results. In our study all 30 AA patients had an immunodominant TCR-Vβ clones among Th and/or TCL cells. We identified the most common clonotypes in comparison with healthy donors - Vβ1, Vβ2, Vβ3 among the Th cells and Vβ3, Vβ9, Vβ13.1 among the TCL cells. In ND group Vβ1 was highly expanded in 5 (38.5%), Vβ3 - in 7 (53.8%) pts among Th, and Vβ3 - in 3 (23.1%) and Vβ9 - in 4 (30.8%) out of 13 pts among TCL. In OR group Vβ2 expansion was in 4 (40%) and Vβ3 - in 5 (50%) pts among Th; Vβ3 in 6 (60%) and Vβ9 in 6 (60%) out of 10 pts among TCL. In NR group the most frequent was Vβ13.1 clone in TCL - in 3 (42.9%) out of 7 pts. In NR group in overall clonal expansion was less frequent than in ND and OR groups. We also analyzed the previously mentioned subpopulations of T-cells in patients with AA in three groups (ND, OR, NR) compared to healthy donors (table 1). We obtained significant differences in the count of naive Th and TCL cells, memory T-cells in all three groups of AA patients compared to donors: proportion of naive Th and TCL cells was significantly higher and proportion of memory Th cells was lower in the donor group than in AA pts. The percent of TCL effectors was higher in ND AA pts compare to donors. We also found that cell count of activated Th (CD4+CD25+) was higher in the group of refractory pts. In OR pts proportion of PD-1-positive Th was higher than in donors. In NR pts Th and TCL co-expressed with PD-L1 were lower compare to donors (table 1). Conclusions. In our study we found immunodominant clonotypes in different AA pts and depletion of the pool of naive T cells. Dynamic observation of changes in the most common clonotypes in AA pts during treatment will provide suitable therapy tactics (allogenic bone marrow transplantation or IST). Disclosures No relevant conflicts of interest to declare.

Mutations in the RNA Component of Telomerase, TERC, in Children with Aplastic Anemia and Myelodysplastic Syndrome: An NMDP Study.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 3736-3736
Author(s):  
Joshua J. Field ◽  
Philip J. Mason ◽  
Yvonne J. Barnes ◽  
Allison A. King ◽  
Monica Bessler ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Stem Cell ◽  
Myelodysplastic Syndrome ◽  
Aplastic Anemia ◽  
Stem Cell Transplant ◽  
Bone Marrow Failure ◽  
Juvenile Myelomonocytic Leukemia ◽  
Cell Transplant ◽  
Bone Marrow Failure Syndrome ◽  
Base Pair Deletion

Abstract Mutations in TERC, the RNA component of telomerase, result in autosomal dominant dyskeratosis congenita (DC), a rare bone marrow failure syndrome. DC is clinically heterogeneous and TERC mutations have been detected in a subset of patients previously diagnosed with idiopathic aplastic anemia (AA) and myelodysplastic syndrome (MDS). Unrecognized TERC mutations are clinically relevant as patients with DC respond poorly to immunotherapy and have an increased risk of complications following conventional conditioning for stem cell transplant (SCT). We aimed to determine the frequency of TERC mutations in pediatric patients with AA and MDS who require a SCT. We obtained 315 blood or bone marrow samples from the National Donor Marrow Program Registry from children under age 18 with bone marrow failure who underwent an unrelated stem cell transplant. We screened these samples for mutations in the TERC gene using direct DNA sequencing. To exclude polymorphisms, we also screened 537 racially diverse healthy controls. The study group was composed of patients with MDS (n=151), AA (n=123), and juvenile myelomonocytic leukemia (JMML) (n=41), which may be difficult to distinguish from MDS. The mean age at the time of transplant was 9 years. We found sequence alterations in the promoter region of TERC in 2 patients. A 2 base pair deletion (-240delCT) was identified in a 4 year-old child with MDS and a 1 year-old child with JMML was found to have a point mutation (-99C→G), which was identified previously in an 18 year-old patient with paroxysmal nocturnal hemoglobinuria and is known to affect the Sp1 binding site. The pathogenicity of this mutation is unclear. In summary, our findings suggest that screening for TERC gene mutations is unlikely to diagnose occult DC in children with severe bone marrow failure who require a stem cell transplant but have no clinical features or history to suggest a familial bone marrow failure syndrome.

Inhibition of Notch Signaling in T Cells Prevents Immune-Mediated Bone Marrow Failure.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 180-180
Author(s):  
Gloria T Shan ◽  
Ivy Tran ◽  
Ashley R Sandy ◽  
Ann Friedman ◽  
Yi Zhang ◽  
...  
Keyword(s):  
Bone Marrow ◽  
T Cells ◽  
T Cell ◽  
Notch Signaling ◽  
Aplastic Anemia ◽  
Research Funding ◽  
Bone Marrow Failure ◽  
Comprehensive Cancer Center ◽  
Cancer Center ◽  
Immune Mediated

Abstract Abstract 180 Aplastic anemia is a severe bone marrow disorder characterized by the loss of hematopoietic stem cells (HSC). HSC destruction is thought to be T cell-mediated in a majority of patients with aplastic anemia. Global immunosuppression and HSC transplantation can induce disease remission, but these treatments are not effective in all patients and can promote life-threatening complications. Thus, novel immunomodulatory approaches are needed in this disorder. Notch is a conserved cell-cell communication pathway that can regulate T cell differentiation and function with context-dependent effects. To study the role of Notch signaling in pathogenic T cells causing immune-mediated bone marrow failure, we inhibited canonical Notch signaling in mature T cells through conditional expression of the pan-Notch inhibitor DNMAML (ROSA-DNMAMLf × Cd4-Cre mice). We used two complementary mouse models of immune-mediated bone marrow failure that mimic features of aplastic anemia: administration of C57BL/6 (B6) T cells into sublethally irradiated (500 rads) minor histocompatibility antigen mismatched BALB/b recipients (Chen et al., J Immunol 2007; 178:4159), or infusion of B6 lymphocytes into unirradiated MHC-mismatched B6×DBA F1 recipients. In contrast to control B6 T cells which led to lethal bone marrow failure in virtually all recipients, DNMAML-expressing Notch-deprived T cells were profoundly deficient at inducing HSC loss in both disease models, leading to markedly improved long-term survival (>90%). Notch-deficient T cells showed a modest decrease in overall expansion within secondary lymphoid organs, but their accumulation in the target bone marrow was preserved. Upon restimulation with anti-CD3 and anti-CD28 antibodies, DNMAML T cells had decreased production of IL-2 and interferon gamma. Activated CD4+ and CD8+ DNMAML T cells had reduced interferon gamma, granzyme B, and perforin transcripts despite preserved induction of the master transcription factors Tb×21 (encoding T-bet) and Eomes. In vivo infusion of CFSE-labeled host-type target cells revealed a decreased cytotoxicity in DNMAML as compared to control B6 T cell recipients. These observations point to a novel spectrum and mechanism of Notch action in mature T cells. Since we have shown recently that canonical Notch signaling is dispensable for the maintenance of adult HSCs (Maillard et al., Cell Stem Cell 2008, 2:356), our findings suggest that Notch inhibition could represent a novel therapeutic modality to target the T cell response and reverse immune-mediated HSC destruction in aplastic anemia. Disclosures: Shan: American Society of Hematology: Research Funding. Zhang:University of Michigan Comprehensive Cancer Center: Research Funding; Damon Runyon Cancer Research Foundation: Research Funding. Maillard:Damon Runyon Cancer Research Foundation: Research Funding; American Society of Hematology: Research Funding; University of Michigan Comprehensive Cancer Center: Research Funding.

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