scholarly journals OP0337 DIFFERENTIAL METHYLATION OF PERIPHERAL BLOOD ADAPTIVE IMMUNE CELLS IN INDIVIDUALS AT HIGH RISK FOR RA AND WITH EARLY RA COMPARED WITH CONTROLS IDENTIFIES PATHWAYS IMPORTANT IN TRANSITION TO ARTHRITIS

2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 207.2-207
Author(s):  
R. Ai ◽  
D. Boyle ◽  
D. Hammaker ◽  
K. Deane ◽  
V. M. Holers ◽  
...  

Background:The “Targeting Immune Responses for Prevention of RA” (TIP-RA) collaboration studies individuals at high risk for developing RA because of serum anti-citrullinated protein antibody positivity in absence of arthritis, and is focused on defining how they transition from at-risk to classifiable disease. One potential mechanism is through alterations in epigenetics patterns in adaptive immune cells.Objectives:Previous studies showed that DNA methylation patterns of early RA (ERA) synoviocytes differ from long-standing RA, suggesting that abnormal methylation occurs early in synovium and evolves over time. To extend these observations, we performed a cross-sectional analysis in TIP-RA of DNA methylation signatures in peripheral blood cells in ERA, at-risk anti-CCP3+ individuals and demographically matched CCP- controls.Methods:Genomic DNA was isolated from two independent cohorts of CCP- (cohorts 1 and 2, respectively: B cell: n = 17/34; memory T cell: n = 21/34; and naïve T cell: n = 21/33), CCP3+ (B cell: n = 18/37; memory T cell: n = 20/36; and naïve T cell: n = 20/35), and CCP3+ ERA (B cell: n = 4/18; memory T cell: n = 5/18; and naïve T cell: n = 5/18) after separating PBMCs using antibodies and magnetic beads. Methylation was measured by Illumina Infinium MethylationEPIC chip. Differentially methylated loci (DMLs) were identified using Welch’s t-test and mapped to gene promoter regions to define DM genes (DMGs). Principal component analysis (PCA) was used to represent relationship among groups. Pathway analysis was applied by Reactome.Results:For the initial cohort, 1494, 1097 and 1330 DMLs were identified among CCP+, CCP- and ERA in B cells, memory T cells and naïve T cells, respectively. For the confirmatory cohort, 523, 793 and 548 DMLs were found in corresponding cell populations. The DML overlap between the 2 cohorts was highly significant (p= 2.48E-77). The DMLs were combined for both groups and corresponded to 411, 412, and 351 DMGs in B cells, memory T cells and naïve T cells. Of these, we found 246, 198 and 195 DMGs between CCP3+ and ERA in each peripheral blood cell population, respectively. PCA showed separation of CCP+, CCP- and ERA in each of the three blood cell types by DMLs (Fig. 1). DMGs were mapped to biological pathways to identify DM pathways. Although most were not significant, there were several highly significant differences comparing CCP+, ERA and CCP- in memory T cells involving pathways, including “Interferon gamma signaling” (FDR 7.48E-14), “PD-1 signaling” (FDR 8.71E-10), “Translocation of ZAP-70 to Immunological synapse” (FDR 4.75E-10), and “Phosphorylation of CD3 and TCR zeta chains” (FDR 8.71E-10).Figure 1.PCA shows the separation of CCP+, CCP- and ERA patients in memory T cells in confirmatory cohort.Conclusion:We identified reproducible methylation signatures of CCP-, CCP+, and ERA in peripheral blood B cells, memory T cells and naïve T cells in initial and confirmatory cohorts. The methylome of ERA also demonstrated a distinctive pattern from CCP+, indicating that progression to RA is accompanied by epigenetic remodeling, especially in T cell signaling and interferon responses. These signatures identify critical pathways in CCP positivity and classifiable RA and could provide the basis of novel interventions to prevent disease.Disclosure of Interests:Rizi Ai: None declared, David Boyle: None declared, Deepa Hammaker: None declared, Kevin Deane Grant/research support from: Janssen, Consultant of: Inova, ThermoFisher, Janseen, BMS and Microdrop, V. Michael Holers Grant/research support from: Janssen, Celgene, and BMS, Andre Matti: None declared, William Robinson: None declared, Jane Buckner Grant/research support from: Bristol-Myers Squibb, Janssen, Navin Rao Shareholder of: Janssen Pharmaceuticals, Employee of: Janssen Pharmaceuticals, Frederic Baribaud Shareholder of: Janssen Research & Development, LLC, Employee of: Janssen Research & Development, LLC, Alyssa Johnsen Employee of: Janssen, Sunil Nagpal Shareholder of: Janssen Pharmaceuticals, Employee of: Janssen Pharmaceuticals, Wei Wang: None declared, Gary Firestein Grant/research support from: Lilly, Janssen, Abbvie

2020 ◽  
Vol 35 (Supplement_3) ◽  
Author(s):  
Atsuki Ohashi ◽  
Madoka Kondo ◽  
Fumitaka Ihara ◽  
Noriyuki Toshima ◽  
Yoshitatsu Ohara ◽  
...  

Abstract Background and Aims We previously reported that an increase of lymphocytes in peritoneal dialysis (PD) effluent was correlated with risk of encapsulating peritoneal sclerosis (EPS). In the present study, we analyzed subsets of lymphocytes in PD effluent by flow cytometry and evaluated their changes every six month to elucidate the etiological background of peritoneal dysfunction. Method We enrolled patients who started PD between 2006 and 2017, and of whom the data for PET and flow cytometric analysis was available at least for three consecutive times with an interval of six months. We excluded the patients who experienced PD peritonitis during the observation period. Consequently, the levels and changes of lymphocyte subset, such as CD4+/CD8+ naïve T cell (CCR7+/CD45RA+), CD4+/CD8+ central memory T cell (CCR7+/CD45RA-), CD4+/CD8+ effector memory T cell (CCR7-/CD45RA-), CD4+/CD8+ terminally differentiated effector memory T cell (CCR7-/CD45RA+), D/P creatinine ratio, FSC ratio of mesothelial cells and lymphocytes (a possible indicator for mesothelial cell size) were analysed in 23 patients over one year. Results We evaluated whether the observed variables on the first evaluation (six months after initiation of PD) affected the changes of D/P creatinine and FSC ratio over one year by a simple linear regression analysis. In the examined variables, only a fraction of CD8+ central memory T cell was significantly correlated with the change rate of D/P creatinine ratio (β=1.47, p=0.001, adjusted R2=0.379). We also evaluated whether the change rate of observed variables was correlated with the change rate of D/P creatinine and FSC ratio by a simple linear regression analysis. A fraction of CD8+ naïve T cell or CD8+ central memory cell was negatively correlated with the change rate of D/P creatinine ratio (naïve T cell; β=-0.058, p=0.022, adjusted R2=0.188, central memory T cell; β=-0.096, p=0.046, adjusted R2=0.137). The change rate of CD8+ effector memory T cell was not significantly correlated with the change rate of D/P creatinine ratio (β=0.172, p=0.096, adjusted R2=0.085). However, the change rate of D/P creatinine ratio tends to be higher in accordance with the increased change rate of CD8+ effector memory T cell by One way ANOVA, where the change rate was divided into three groups in descending order (p=0.0796) (Fig.1). Besides, the change rate of CD8+ effector memory T cell tends to be higher in accordance with the increased fraction of CD8+ central memory T cell at the first evaluation by Kruskall-Wallis test, where the change rate was divided into three groups in descending order (p=0.169) (Fig.2). Conclusion A decrease in the fraction of CD8+ naïve or central memory T cell was significantly correlated with the increase of D/P creatinine ratio. An Increase in the fraction of CD8+ effector memory T cell was also possibly correlated with the increase of D/P creatinine ratio, although it was not statistically significant (p=0.096). An initial fraction of CD8+ central memory T cell was significantly correlated with the change rate of D/P creatinine ratio. From these results, central memory T cells and naïve T cells at an initial stage may be transformed into effector memory T cells by repeated exposure to unknown antigens derived from PD solution and these effector memory T cells may damage the peritoneum to increase D/P creatinine ratio. An initial higher fraction of CD8+ central memory T cell suggested an acceleration in the transformation into CD8+ effector memory T cell.


Immunology ◽  
2006 ◽  
Vol 119 (3) ◽  
pp. 376-384 ◽  
Author(s):  
Darragh Duffy ◽  
Chun-Ping Yang ◽  
Andrew Heath ◽  
Paul Garside ◽  
Eric B. Bell

2013 ◽  
Vol 2013 ◽  
pp. 1-12 ◽  
Author(s):  
Jean-François Daudelin ◽  
Mélissa Mathieu ◽  
Salix Boulet ◽  
Nathalie Labrecque

Following activation, naïve CD8+T cells will differentiate into effectors that differ in their ability to survive: some will persist as memory cells while the majority will die by apoptosis. Signals given by antigen-presenting cells (APCs) at the time of priming modulate this differential outcome. We have recently shown that, in opposition to dendritic cell (DC), CD40-activated B-(CD40-B) cell vaccination fails to efficiently produce CD8+memory T cells. Understanding why CD40-B-cell vaccination does not lead to the generation of functional long-lived memory cells is essential to define the signals that should be provided to naïve T cells by APCs. Here we show that CD40-B cells produce very low amount of IL-6 when compared to DCs. However, supplementation with IL-6 during CD40-B-cell vaccination did not improve memory generation. Furthermore, IL-6-deficient DCs maintained the capacity to promote the formation of functional CD8+effectors and memory cells. Our results suggest that in APC vaccination models, IL-6 provided by the APCs is dispensable for proper CD8+T-cell memory generation.


Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 1071-1071
Author(s):  
Melody M. Smith ◽  
Cynthia R. Giver ◽  
Edmund K. Waller ◽  
Christopher R. Flowers

Abstract Ex vivo modification of donor lymphocytes with purine analogs (mDL) may help to minimize graft versus host disease (GvHD) while providing beneficial graft versus leukemia (GvL) effects. In a murine model system, we have shown that allogeneic donor splenocytes, treated with fludarabine ex vivo have significantly reduced GvHD activity when transferred to irradiated recipient mice, and retain anti-viral and GvL activities (Giver, 2003). This effect appears to be mediated by relative depletion of donor CD4 CD44low, “naive” T-cells. As a first step toward developing mDL for use in patients, we sought to evaluate the effects of ex vivo fludarabine exposure on human T-cell subsets, and to determine the minimum dose of fludarabine required to achieve this effect. Methods: Peripheral blood mononuclear cell samples from 6 healthy volunteers were evaluated at 0, 24, 48, and 72 hour time points after ex vivo incubation in varying dosages of fludarabine: 2, 5, and 10(n=3) mcg/ml. Fludarabine incubated samples were compared to samples that received no fludarabine (untreated). The total viable cell number was determined and the fractions and absolute numbers of viable CD4 and CD8 naïve and memory T-cells were determined using flow cytometry after incubation with 7-AAD (dead cell stain), CD4, CD8, CD45RA, CD62L, and CCR7 antibodies, and measuring the total viable cells/ml. Results: The numbers of viable CD4 and CD8 T-cells remained relatively stable in control cultures. Without fludarabine, the average viability at 72 hr of naive and memory T-cells were 92% and 77% for CD4 and 86% and 63% for CD 8 (Fig. 1A). Naive CD4 T-cells were more sensitive to fludarabine-induced death than memory CD4 cells. At 72 hr, the average viability of fludarabine-treated naive CD4 T-cells was 33% at 2 mcg/ml (8.2X the reduction observed in untreated cells) and 30% at 5 mcg/ml, while memory CD4 T-cells averaged 47% viability at 2 mcg/ml (2.3X the reduction observed in untreated cells) (Fig. 1B) and 38% at 5 mcg/ml. The average viability of naive CD8 T-cells at 72 hr was 27% at 2 mcg/ml and 20% at 5 mcg/ml, while memory CD8 T-cell viability was 22% at 2 mcg/ml and 17% at 5 mcg/ml. Analyses on central memory, effector memory, and Temra T-cells, and B-cell and dendritic cell subsets are ongoing. The 5 and 10 mcg/ml doses also yielded similar results in 3 initial subjects, suggesting that 2 mcg/ml or a lower dose of fludarabine is sufficient to achieve relative depletion of the naive T-cell subset. Conclusions: Future work will determine the minimal dose of fludarabine to achieve this effect, test the feasibility of using ex vivo nucleoside analog incubation to reduce alloreactivity in samples from patient/donor pairs, and determine the maximum tolerated dose of mDL in a phase 1 clinical trial with patients at high risk for relapse and infectious complications following allogeneic transplantation. Figure Figure


Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 3500-3500 ◽  
Author(s):  
Vincent Ribrag ◽  
Silvia Damien ◽  
Mecide Gharibo ◽  
Mercede Gironella ◽  
Armando Santoro ◽  
...  

Abstract Background: CC-122 is a novel non-phthalimide analog of the IMiDs® immunomodulatory drugs (lenalidomide and pomalidomide) and a first in class PPMTM (Pleiotropic Pathway Modifier) compound with multiple biological activities including potent anti-proliferative activity against B-lineage cells (10-fold greater than lenalidomide), anti-angiogenic activity (100-fold greater than lenalidomide) and immunomodulatory effects (10-fold greater than lenalidomide). The molecular target of CC-122 is cereblon (CRBN), a substrate receptor of the Cullin ring E3 ubiquitin ligase complex (CRL4CRBN). CC-122 promotes ubiquitination of lymphoid transcription factors Ikaros (IKZF1) and Aiolos (IKZF3) in a CRBN-dependent manner, leading to their subsequent degradation. Following establishment of 3mg once daily (QD) as the maximum tolerated dose (Blood 122:2905 2013), patients with advanced aggressive non-Hodgkin lymphoma (NHL), multiple myeloma (MM), and select solid tumors were enrolled in parallel expansion cohorts of up to 20 evaluable patients. CC-122 was dosed at 3 mg QD in 28-day cycles until disease progression. Results: As of May 1, 2014, 93 total patients were enrolled in the expansion phase of the study. The NHL cohort included 21 patients with diffuse large B-cell lymphoma (DLBCL) and 1 patient with mantle cell lymphoma, and twenty-four patients were enrolled in the MM cohort. Results in solid tumor cohorts will be reported separately. All patients were ECOG performance status 0-2, the median number of prior systemic therapies was 4 (NHL) and 6 (MM). The most common (> 20%) adverse events (AEs) (grades 1-4) included neutropenia (69.6%), anemia (52%), asthenia (50%), pyrexia (35%), diarrhea (30%), cough (30%), thrombocytopenia (28%), and constipation (22%). Grade 3/4 AEs occurring in more than one patient were neutropenia (52%), anemia (26%), febrile neutropenia (13%), and thrombocytopenia (7%). CC-122 dose reduction was required in 36.4% of patients with NHL and 63% of patients with MM, the majority of which was due to neutropenia and occurred during cycle 1 or 2. CC-122 systemic exposure in NHL and MM patients was generally comparable after administration of single and multiple doses. Peak concentrations were observed between 30 minutes and 2 hours (median Tmax concentration = 1.5 h). Four treated patients with DLBCL had objective responses; one patient with complete response (CR) and 3 with partial responses (PR). Responses were observed in patients with germinal center B cell (GCB), non-GCB and Myc/Bcl2 over-expressing DLBCL. Four treated patients with MM had PR, and two of these responders were progression free beyond 10 cycles. A single dose of CC-122 3mg resulted in decreased Aiolos protein expression at 1.5 and 5 hours compared with baseline in peripheral B cells (median 38% and 53%) and T cells (median 31% and 54%) in the combined NHL (n = 16) and MM (n = 19) cohorts. Decrease in expression of Aiolos protein from baseline was also observed in lymph node biopsies of patients with DLBCL. Furthermore, CC-122 treatment decreased CD19+ B cells (median = 57% of baseline), expanded CD4-/CD8+/CD45RA-/CD45RO+ cytotoxic memory T cells (median = 320% of baseline), and expanded CD4+/CD8-/CD45RA-/CD45RO+ helper memory T cells (median = 154% of baseline) in peripheral blood samples from patients with MM (n = 9) and NHL (n = 3-12) subjects. Additionally, ex vivo activation of T cells after a single dose of CC-122 compared with baseline, as measured by IL-2 production, increased by a median of 776% (NHL n = 3 and MM n = 7). Conclusions: CC-122 shows promising initial clinical and pharmacodynamic activity in heavily pretreated relapse/refractory NHL and MM patients. Biomarker analysis indicates that the 3 mg QD dose of CC-122 results in rapid CRBN target engagement and Aiolos degradation in the peripheral blood lymphocytes of patients with NHL and MM patients and in NHL tumor tissue. Exploration of an intermittent dosing to mitigate neutropenia-related dose reductions and interruptions is ongoing and clinical studies exploring drug combinations with CC-122 are underway. Disclosures Ribrag: Celgene Corp: Consultancy. Rasco:Celgene Corp: Membership on an entity's Board of Directors or advisory committees. Wei:Celgene Corp: Employment, Equity Ownership. James:Celgene Corp: Employment. Hagner:Celgene Corp: Employment, Equity Ownership. Gandhi:Celgene Corp: Employment, Equity Ownership. Chopra:Celgene Corp: Employment, Equity Ownership. DiMartino:Celgene Corp: Employment, Equity Ownership. Pourdehnad:Celgene Corp: Employment, Equity Ownership. Stoppa:Celgene Jansen: Honoraria.


2019 ◽  
Vol 21 (1) ◽  
pp. 49-58 ◽  
Author(s):  
M. B. Rayev ◽  
L. S. Litvinova ◽  
K. A. Yurova ◽  
O. G. Khaziakhmatova ◽  
V. P. Timganova ◽  
...  

The role of pregnancy-specific β1-glycoprotein (PSG) in the regulation of molecular genetic factors determining the functional activity of naїve T cells and T cells of immune memoryin vitrowas studied. Human PSG was isolated with a proprietary immuno-purification method using a biospecific sorbent followed by removing of immunoglobulin contamination with a HiTrapTMProtein G HP column. Physiological concentrations of PSG were used in the experiments. They corresponded to PSG levels in the peripheral blood of pregnant woman: 1, 10 and 100 μg/ml (I, II, III trimester, respectively). The objects of study were monocultures of naїve T cells (CD45RA+) and memory T cells (CD45R0+), obtained by immunomagnetic separation from the peripheral blood of women of reproductive age.It was established that at the level of naїve T cells (CD45RA+) PSG inhibited the expression of CD28 (1, 10, 100 μg/ml) and CD25 (100 μg/ml), without affecting the interleukin-2 (IL-2) production by these cells. At the same time, PSG in all concentrations studied suppressed the expression of CD25 at the immune memory T-cell (CD45R0+) surface but increased the IL-2 production. Expression ofU2af1l4, Gfi1, hnRNPLLgenes regulating the alternative splicing of the Ptprc gene encoding CD45 was also evaluated. It was found, that PSG reduced the expression of theGfi1(1, 10, 100 μg/ml),hnRNPLL(10, 100 μg/ml) genes, but increased the expression of theU2af1l4gene (1, 10, 100 μg/ml) in the naїve T cells. It was shown that at the immune memory T-cells’ level the effects were similar, with PSG rendering them in all concentrations used. The revealed changes in the mRNA transcription ofU2af1l4,Gfi1andhnRNPLLgenes in the studied T cell subsets may lead to the inhibition of CD45 “mature” isoform formation – CD45R0.Thus, PSG reduces the functional activity of naїve T cells and immune memory T cells associated with the expression of costimulation/activation molecules CD25 and CD28 and is involved in the regulation ofPtprcgene alternative splicing, which determines the ratio of CD45 molecule variants. Apparently, using these mechanisms, PSG regulates the functional activity of the memory T cell circulating pool, which is potentially capable of carrying out antigen-specific cytotoxic reactions against fetal antigens in vivo. In general, the data obtained broadens the notion of the PSG role in the regulation of molecular-genetic mechanisms of naїve T cells and immune memory T cells differentiation.


Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 3590-3590
Author(s):  
Michelle S. Bryson ◽  
Ruth F. Jarrett ◽  
Lesley Sheild ◽  
Gerard J. Graham

Abstract Chemokines are small peptides (∼8-14KDa) that play an essential role in both the innate and adaptive immune system. Chemokines are primarily involved in leukocyte trafficking, but are also involved in a number of cellular mechanisms. They elicit their effect through G-protein coupled receptors, the chemokine receptors (CKR). Functionally chemokines and their receptors are classified as inflammatory or constitutive. Constitutive CKRs and their ligands have a role in numerous diseases including malignancy, chronic inflammation and HIV infection. This study aimed to examine constitutive CKR expression in sub-types of B-cell NHL, of which there are limited studies so far. Lymph node preparations from patients with NHL were examined by flow cytometry using antibodies to CD20, CCR4, CCR6, CCR7, CCR9, CCR10, CXCR4 and CXCR5. The percentage of CD20 positive cells expressing the CKR under investigation was then calculated. The following cases were examined; follicular lymphoma (FL), n=11, Diffuse large B-cell lymphoma (DLBCL), n=11, mantle cell lymphoma (MCL) n=17, Burkitt’s lymphoma (BL), n=9 and MALT lymphoma, n=10. A number of differences between NHL sub-types were detected. FL cases generally had a lower expression of all the CKRs. CXCR5 and CXCR4 expression was high in all sub-types (>84% of B-cells) with no significant differences found, this would be expected as these CKRs are widely expressed in all B-cells. CCR10 expression was low or absent, with no significant differences detected. CCR6 and CCR9 show highest expression in MALT lymphomas, consistent with previous studies, but in comparison with other sub-types the differences was not significant. The most significant results were found with CCR7 and CCR4. CCR7 is expressed on naive T-cells, memory T-cells, B-cells and dendritic cells and is involved in the homing of lymphocytes to lymph nodes. CCR7 is currently the second most commonly reported CKR to be upregulated in malignancy, after CXCR4 and is related. We found very high levels of CCR7 in Mantle cell lymphoma (>90% of B-cells) as compared to other sub-types (p=0.005). CCR4 is expressed on Th2 and Treg lymphocytes, memory T cells and in a small subset of mature B-cells. CCR4 expression in T-cells has been correlated with an adverse prognosis in T-cell NHL and Hodgkin’s lymphoma, yet no systematic studies looking at CCR4 expression in B-cell neoplasms has been reported. These results showed a significant increase in CCR4 expression (>50% of B-cells) in DLBCL, MCL, MALT and BL as compared to FL (p<0.0001). We showed that there are differences in constitutive CKR expression in the different B-cell NHL types, with CCR4 expression being the most interesting finding. How CCR4 expression relates to prognosis in these lymphomas is as yet unknown but is under investigation. Targeting of the chemokine system using anti-CCR4 is already being used in clinical trials for T-cell neoplasms, and may be of potential benefit in selected B-cell neoplasms. Furthermore, the development of anti-CCR7 strategies may prove to be of benefit in the traditionally poor prognosis MCL patients.


Author(s):  
Craig M. Rive ◽  
Eric Yung ◽  
Lisa Dreolini ◽  
Daniel J. Woodsworth ◽  
Robert A. Holt

AbstractAnti-CD19 CAR-T therapy for B cell malignancies has shown clinical success, but a major limitation is the logistical complexity and high cost of manufacturing autologous cell products. Direct infusion of viral gene transfer vectors to initiate in vivo CAR-T transduction, expansion and anti-tumor activity could provide an alternative, universal approach for CAR-T and related immune effector cell therapies that circumvents ex vivo cell manufacturing. To explore the potential of this approach we first evaluated human and murine CD8+ T cells transduced with VSV-G pseudotyped lentivectors carrying an anti-CD19CAR-2A-GFP transgene comprising either an FMC63 (human) or 1D3 (murine) anti-CD19 binding domain. To evaluate CD19 antigen-driven CAR-T proliferation in vitro we co-cultured transduced murine T cells with an excess of irradiated splenocytes and observed robust expansion over a 9 week period relative to control T cells transduced with a GFP transgene (mean fold expansion +/- SD: ID3-CD19CAR-GFP modified T cells, 12.2 +/- 0.09 (p < 0.001); FMC63-CD19CAR-GFP modified T cells 8.8 +/- 0.03 (p < 0.001). CAR-T cells isolated at the end of the expansion period showed potent B cell directed cytolytic activity in vitro. Next, we administered approximately 20 million replication-incompetent lentiviral particles carrying either ID3-CD19CAR-GFP, FMC63-CD19CAR-GFP, or GFP-only transgene to to wild-type C57BL/6 mice by tail vein infusion and monitored the dynamics of immune cell subsets isolated from peripheral blood at weekly intervals. We saw emergence of a persistent CAR-transduced CD3+ T cell population beginning week 3-4 that reaching a maximum of 13.5 +/- 0.58 % (mean +/- SD) and 7.8 +/- 0.76% of the peripheral blood CD3+ T cell population in mice infused with ID3-CD19CAR-GFP lentivector or FMC63-CD19CAR-GFP lentivector, respectively, followed by a rapid decline, in each case of, the B cell content of peripheral blood. Complete B cell aplasia was apparent by week 5 and was sustained until the end of the protocol (week 8). None of these changes were observed in mice infused with GFP-only control lentivector, and significant CAR positive populations were not observed within other immune cell subsets, including macrophage, natural killer, or B cells. Within the T cell compartment, CD8+ effector memory cells were the predominant CAR-positive subset. Modest weight loss of 5.5 +/- 2.97 % (mean +/- SD) observed in some animals receiving an anti-CD19CAR-GFP transgene during the protocol. These results indicate that direct IV infusion of lentiviral particles carrying an anti-CD19 CAR transgene can transduce T cells that then fully ablate endogenous B cells in wild type mice. Based on these results it may be useful to further explore, using currently available vectors, the feasibility of systemic gene therapy as a modality for CAR-T intervention.


Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 2061-2061
Author(s):  
Michael Loschi ◽  
Régis Peffault de Latour ◽  
Raphael Porcher ◽  
Valerie Vanneaux ◽  
Marie Robin ◽  
...  

Abstract Introduction Acute graft versus host disease is a frequent and life threatening complication following HSCT. Some predictive factors have been identified in the last decades. Experimental studies in mice suggest that the naïve cytotoxic T cells (CD3+/CD8+/CD45RA+/CD62L+) are the major mediators of acute GVHD and that removing this subset of the donor T cells, called ‘naïve T cells’, before transplant may reduce the frequency and intensity of GVHD. Detailed immunophenotyping of the graft including naïve and memory (CD3+/CD8+/CD45RA-/CD62L- ; CD3+/CD8+/CD45RA+/CD62L- ; CD3+/CD8+/CD45RA-/CD62L+ ) T-cell contents have never been explored in human GVHD. We studied the correlation between memory and naive T cell in bone marrow and peripheral blood grafts and development of acute GVHD after hematopoietic stem cell transplant. Methods We analyzed by detailed immunophenotyping, the grafts of a cohort of 210 patients among 402 patients who received an allogeneic stem cell transplantation from bone marrow and peripheral blood between January 2009 and June 2012 at a single center. There were no differences between the 210 studied patients and the other 192 in whom grafts were not studied. Characteristics of patients investigated for naïve and memory T cells were compared using Wilcoxon rank-sum tests and Fisher’s exact tests. The main outcome was occurrence of acute GVHD grade II – IV. Cumulating incidence of acute GVHD was estimated using usual methods and compared according to tertiles of T cytotoxic lymphocytes subpopulations using Gray’s test. Adjusted analyses were performed using Fine- Gray proportional hazards models. All tests were two - sided and p-values ≤ 0.05 were considered as indicating significant association. T cytotoxic lymphocytes were typed in all 210 grafts using CD3, CD8, CD45 RA and CD62L four colors immuphenotyping. Clinical and histological characteristics of patients were recorded. Including age, gender, ABO group and rhesus, viral serology of both the donor and the patient, characteristic of the grafts including HLA compatibility, bone marrow or peripheral blood, lymphocytes and nucleated cell and CD34 numeration, conditioning regimens, GVHD prophylaxis, characteristics of GVHD (date of onset, organs involved, stage and grade). Results Median follow up from transplant was 18 months. Cumulative incidence of acute GVHD was 59% (95% CI range 45 to 59) overall, and 49% (95% CI 42 to 56) at 100 days. In univariate analysis increased absolute counts of memory T cell subtypes were significantly correlated with the onset of an acute GVHD grade II – IV. Risk factors for acute GVHD (multivariate analysis) were use of an unrelated donor, positive CMV donor for a negative recipient, and use of TBI 12Gy. In a multivariate analysis the subtype CD3+/CD8+/CD45 RA-/CD62L- was associated with the onset of acute GVHD grade II-IV (adjusted Hazard Ratio = 1.26 and 1.98, p=0.02). Adjusting analysis on the total number of total nucleated cells infused did not affect the results. Restricting analyses to patients receiving peripheral blood stem cells also provided same conclusions. Conclusion This first study on the relation between rate of memory T cell and GVHD revealed that CD3+/CD8+/CD45 RA-/CD62 L- T-cells numbers and percentage were associated with acute GVHD grade II – IV. In contrast to murine models we did not find evidence for a link between naïve T-cells and GVHD risk Disclosures: Robin: novartis: Research Funding.


2019 ◽  
Vol 20 (6) ◽  
pp. 1415 ◽  
Author(s):  
Caroline Mangare ◽  
Sabine Tischer-Zimmermann ◽  
Sebastian B. Riese ◽  
Anna C. Dragon ◽  
Immo Prinz ◽  
...  

Viral infections and reactivations remain a serious obstacle to successful hematopoietic stem cell transplantation (HSCT). When antiviral drug treatment fails, adoptive virus-specific T-cell transfer provides an effective alternative. Assuming that naive T cells (TN) are mainly responsible for GvHD, methods were developed to generate naive T-cell-depleted products while preserving immune memory against viral infections. We compared two major strategies to deplete potentially alloreactive T cells: CD45RA and CD62L depletion and analyzed phenotype and functionality of the resulting CD45RA−/CD62L− naive T-cell-depleted as well as CD45RA+/CD62L+ naive T-cell-enriched fractions in the CMV pp65 and IE1 antigen model. CD45RA depletion resulted in loss of terminally differentiated effector memory T cells re-expressing CD45RA (TEMRA), and CD62L depletion in loss of central memory T cells (TCM). Based on these differences in target cell-dependent and target cell-independent assays, antigen-specific T-cell responses in CD62L-depleted fraction were consistently 3–5 fold higher than those in CD45RA-depleted fraction. Interestingly, we also observed high donor variability in the CD45RA-depleted fraction, resulting in a substantial loss of immune memory. Accordingly, we identified donors with expected response (DER) and unexpected response (DUR). Taken together, our results showed that a naive T-cell depletion method should be chosen individually, based on the immunophenotypic composition of the T-cell populations present.


Sign in / Sign up

Export Citation Format

Share Document