Increased Peripheral T Cell Responses to EBV-Infected Cells with Frequent Detection of EBV-DNA In Plasma and Viral mRNA In Peripheral B-Cells In Immunocompetent EBV-Positive Diffuse Large B-Cell Lymphoma Patients

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 4163-4163 ◽  
Author(s):  
Satoko Morishima ◽  
Kazuhito Yamamoto ◽  
Hiroshi Kimura ◽  
Seiko Iwata ◽  
Tomohiro Kinoshita ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
B Cells ◽  
B Cell ◽  
Cd8 T Cells ◽  
Cd4 T Cells ◽  
B Cell Lymphoma ◽  
Viral Mrna ◽  
Ebv Dna ◽  
Ifn Γ

Abstract Abstract 4163 Introduction: It is well known that immunocompromised patients(pts) such as post-transplantation or HIV infection are at increased risk of EBV-associated B-cell lymphoproliferaitive disorders. However, the immunological status of immunocompetent EBV-positive diffuse large B-cell Lymphoma (DLBCL) has not been well elucidated. For example, EBV-positive DLBCL in the elderly is defined as an EBV-positive clonal B-cell lymphoid proliferation occurring in pts more than 50 years of age and without any known immunodeficiency in WHO classification 2008, accounting for 5 – 10% of DLBCL in Japan. This disease is speculated to be related to the immunological deterioration accompanying the aging process. We conducted a multi-center prospective study to assess EBV status and the T cell response to EBV of peripheral blood (PB) in EBV-positive DLBCL in comparison with EBV-negative DLBCL pts and normal old-healthy persons (old-HPs). Patients and Methods: Fifteen newly-diagnosed pts with EBV-positive DLBCL, 8 pts with EBV-negative DLBCL, and 16 old-HPs were enrolled. Median ages of pts with EBV-positive DLBCL, pts with EBV-negative DLBCL, and old-HPs were 74.5 years (range 29–82 years), 71 years (48-79), and 65 years (60-74), respectively. Among the 15 pts with EBV-positive DLBCL, 2 were pyothorax-associated lymphoma, 2 were treated with methotrexate for rheumatoid arthritis, and the remaining 11 pts were without past histories predisposing to immunodeficiency. The diagnosis of EBV-positive DLBCL was made by positive signals for in situ hybridization using EBV-encoded small RNA (EBER) on paraffin section. To analyze T cell reactivity to autologous EBV-infected B-cell lymphoblastoid cell lines (LCL), CFSE-labeled peripheral blood mononuclear cells (PBMCs) were co-cultured with irradiated autologous LCL, and the division indices (DI) of CD4+ and CD8+ T cells were determined on day 5 (Cytometry 34:143, 1998). Percentage of proliferating CFSElow IFN-γ+CD4+ T cells and CFSElow IFN-γ+CD8+ T cells was assessed on day 7. EBV DNA load in PBMCs and plasma was determined by quantitative real-time PCR. CD19+ B cells were separated from of PBMCs by immunomagnetic sorting, and viral mRNA expression of B cells was quantified by one-step multiplex real-time RT-PCR. Results: (1) Plasma EBV-DNA was detectable in 13 of the 15 EBV-positive DLBCL pts but in none of the 8 EBV-negative DLBCL pts or the 16 old-HPs. Copy number of EBV-positive DLBCL was significantly higher than EBV-negative DLBCL (p<0.00001) or old-HPs (p=0.0001). EBV-DNA in PBMC was positive in 10 of the 15 EBV-positive DLBCL pts, 2 of 8 EBV-negative DLBCL pts, and 2 of 15 old-HPs. (2) EBER1 of PB B cells was detected in all 10 EBV-positive DLBCL pts, 4 of 7 EBV-negative DLBCL pts, and 7 of 14 old-HPs. BamHI A rightward transcripts (BARTs) of B-cells was detected in 8 of 10 EBV-positive DLBCL pts, 3 of 10 EBV-negative DLBCL pts, and 2 of 14 old-HPs. Latent membrane protein 2 (LMP2) of B cells was detected in 2 of 10 EBV-positive DLBCL pts, 2 of 14 old-HPs, and none of 5 EBV-negative DLBCL pts. LMP1 of B cells was detected in 1 of 10 EBV-positive DLBCL pts, none of 7 EBV-negative DLBCL pts, and none of 14 old-HPs. EBV-encoded nuclear antigen 1 (EBNA1) or EBNA2 were not detected in any of the pts nor old-HPs. (3) DI of CD4+ T cells for 5 days in EBV-positive DLBCL (median 1.41) was significantly higher than in old-HPs (median 0.53) (p=0.0009), and DI of CD8+ T cells of EBV-positive DLBCL (median 1.94) showed a higher tendency than old-HP (median 1.35). (4) Percentage of CFSE-low IFN-γ+CD4+ T cells in EBV-positive DLBCL (median 9.8%) was significantly higher than in old-HPs (median 2.2%) (p=0.002), and percentage of CFSE-low IFN-γ+CD8+ T cells in EBV-positive DLBCL (median 12.0%) was significantly higher than in old-HPs (median 6.6%)(p=0.025). Conclusions: Measurement of the plasma EBV-DNA copy number is a good indicator for the diagnosis of EBV-positive DLBCL, and the frequent detection of EBV viral mRNA of peripheral B-cells in EBV-positive DLBCL pts might be associated with greater viral load. Proliferative and INF-γ secreting responses of both peripheral CD4+ T cells and CD8+ T cells to EBV-infected cells were increased in EBV-positive DLBCL compared to old-HPs, which might be driven by an elevated viral load. These findings suggest that systemic immunological reaction to EBV might be intact in EBV-positive DLBCL. Disclosures: No relevant conflicts of interest to declare.

Low Incidence of Post-Transplant EBV-Related Disease After Alemtuzumab-Mediated T Cell Depletion Is Explained by the Differential Susceptibility to Alemtuzumab of B Cells and Protective CD8 and CD4 T Cells

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 2330-2330
Author(s):  
Constantijn J.M. Halkes ◽  
Inge Jedema ◽  
Judith Olde Wolbers ◽  
Esther M van Egmond ◽  
Peter A. Von Dem Borne ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
B Cells ◽  
B Cell ◽  
Cd8 T Cells ◽  
Cd4 T Cells ◽  
Cell Depletion ◽  
T Cell Depletion

Abstract Abstract 2330 In vivo T cell depletion with anti-thymocyte globulin (ATG) or alemtuzumab (anti-CD52) before reduced intensity allogeneic stem cell transplantation (alloSCT) in combination with in vitro T cell depletion with alemtuzumab reduces the risk of GVHD. Detectable levels of circulating antibodies are present up to several months after the alloSCT, leading to a delayed immune reconstitution which is associated with an increased incidence of opportunistic infections and early relapses. Prior to 2007, combined in vitro (Alemtuzumab 20 mg added “to the bag”) and in vivo T cell depletion with horse-derived ATG (h-ATG) resulted in good engraftment without GVHD in the absence of GVHD prophylaxis after reduced intensity alloSCT using conditioning with fludarabine and busulphan. Due to the unavailability of h-ATG, rabbit-derived ATG (r-ATG) 10–14 mg/kg was introduced in the conditioning regimen in 2007. Strikingly, in this cohort of patients, early EBV reactivation and EBV-associated post-transplantation lymphoproliferative disease (PTLD) was observed in 10 out of 18 patients at a median time of 6 weeks after alloSCT (range 5 to 11 weeks) in the absence of GVHD or immunosuppressive treatment. Analysis of T and B cell recovery early after transplantation revealed preferential depletion of T cells as compared to B cells, thereby allowing unrestricted proliferation of EBV infected B cells. Due to this unacceptable high incidence of EBV-related complications, in the conditioning regimen r-ATG was replaced by low dose alemtuzumab (15 mg i.v. day -4 and -3) in 2008. In this cohort of 60 patients, only 2 patients experienced transient EBV reactivation during the first 3 months after alloSCT and one patient developed an EBV-associated lymphoma 4 weeks after alloSCT. To investigate the mechanisms underlying the low incidence of EBV reactivation using alemtuzumab for T cell depletion, we studied the in vivo and in vitro effects of alemtuzumab on different lymphocyte subsets. First, lineage-specific reconstitution was studied in 20 patients from the alemtuzumab cohort with known CD52 negative diseases (11 AML and 9 multiple myeloma) to exclude the confounding effect of antibody absorption by malignant cells. Whereas at 3 weeks after alloSCT detectable numbers of circulating NK cells and T cells were observed (medians 71 (range 6–378), and 12 (range 1–1164)E6/L, respectively), no circulating B cells could be detected (median 0, range 0–1 E6/L). At 6 weeks after alloSCT, NK and T cell numbers further increased (medians 212 (52-813), and 130 (range 25–1509)E6/L, respectively), whereas B cell numbers still remained low in the majority of patients (median 15, range 0–813E6/L). In all patients, T cells were detectable before the appearance of circulating B cells. Furthermore, the expression of CD52 and the sensitivity to alemtuzumab-mediated complement-dependent cell lysis (CDC) of B cells, T cells and NK cells was measured in vitro. The highest CD52 expression was observed on B cells (mean fluorescence intensity (MFI) 120), resulting in 95% lysis after incubation with 10ug/mL alemtuzumab and rabbit complement. NK cells showed a significantly lower CD52 expression (MFI 41), which was also reflected by a lower susceptibility to alemtuzumab-mediated CDC (62% lysis). Interestingly, differential expression of CD52 was observed on CD4 and CD8 T cells (MFI 120 and 101, respectively). Cytotoxicity analysis revealed relative protection of CD8 compared to CD4 T cells against alemtuzumab-mediated CDC, resulting in 52% and 90% lysis, respectively. Based on these results, we investigated in detail the presence and phenotype of the CD4 and CD8 subsets and EBV-specific CD8 T cells using tetramer staining at 6 weeks after alloSCT. In accordance with the in-vitro expression and susceptibility data, circulating CD52+ CD8 T cells including EBV-specific T cells were detectable. Interestingly, the majority of circulating CD4 T cells (64-93%, n=4) lacked CD52 expression, explaining their capacity to persist in the presence of alemtuzumab. We conclude that in vivo and in vitro T cell depletion with alemtuzumab is associated with a relatively low risk of EBV-associated PTLD because of efficient B cell depletion and persistent EBV immunity allowed by the relative insusceptibility for alemtuzumab of CD8 T cells and the development of CD52 negative escape variants of CD4 T cells. Disclosures: No relevant conflicts of interest to declare.

scholarly journals An Optimized CD4 T-Cell Response Can Control Productive and Latent Gammaherpesvirus Infection

2004 ◽  
Vol 78 (13) ◽  
pp. 6827-6835 ◽  
Author(s):  
Rebecca L. Sparks-Thissen ◽  
Douglas C. Braaten ◽  
Scott Kreher ◽  
Samuel H. Speck ◽  
Herbert W. Virgin
Keyword(s):  
T Cells ◽  
T Cell ◽  
B Cells ◽  
B Cell ◽  
Cd8 T Cells ◽  
Cd4 T Cells ◽  
Acute Infection ◽  
Cd8 T Cell ◽  
T Cell Response ◽  
Cd4 T Cell

ABSTRACT CD4 T cells are important for control of infection with murine gammaherpesvirus 68 (γHV68), but it is not known whether CD4 T cells function via provision of help to other lymphocyte subsets, such as B cells and CD8 T cells, or have an independent antiviral function. Moreover, under conditions of natural infection, the CD4 T-cell response is not sufficient to eliminate infection. To determine the functional capacities of CD4 T cells under optimal or near-optimal conditions and to determine whether CD4 T cells can control γHV68 infection in the absence of CD8 T cells or B cells, we studied the effect of ovalbumin (OVA)-specific CD4 T cells on infection with a recombinant γHV68 that expresses OVA. OVA-specific CD4 T cells limited acute γHV68 replication and prolonged the life of infected T-cell receptor-transgenic RAG (DO.11.10/RAG) mice, demonstrating CD4 T-cell antiviral activity, independent of CD8 T cells and B cells. Despite CD4 T-cell-mediated control of acute infection, latent infection was established in DO.11.10/RAG mice. However, OVA-specific CD4 T cells reduced the frequency of latently infected cells both early (16 days postinfection) and late (42 days postinfection) after infection of mice containing CD8 T cells and B cells (DO.11.10 mice). These results show that OVA-specific CD4 T cells have B-cell and CD8 T-cell-independent antiviral functions in the control of acute infection and can, in the absence of preexisting CD8 T-cell or B-cell immunity, inhibit the establishment of gammaherpesvirus latency.

Correlation of IFNγ, CD107 and CD137 at the Single Cell Level Can Be Used To Monitor T Cell Responses in Patients after Immunotherapy.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 2306-2306
Author(s):  
Debra K. Czerwinski ◽  
Joshua D. Brody ◽  
Ronald Levy
Keyword(s):  
Flow Cytometry ◽  
Immune Response ◽  
T Cells ◽  
T Cell ◽  
B Cell ◽  
Cd8 T Cells ◽  
Cell Lymphoma ◽  
B Cell Lymphoma ◽  
Cell Responses ◽  
Ifn Γ

Abstract As immunotherapies become increasingly important in the treatment of various cancers, monitoring the immune response to reflect the efficacy of the therapy also becomes increasingly important. Previously, tumor antigen-specific humoral responses in patients receiving vaccines for low-grade follicular lymphoma (FL) correlated with clinical outcomes, including tumor regression, molecular remission, progression free survival (PFS) and overall survival (OS). By contrast, T cell immune responses have been difficult to validate. T cell proliferation assays, mostly, measure CD4 T cell responses; whereas, CD8 T cells may be the important effectors generated by immunotherapies. However, assays designed to measure CD8 T cells, i.e. chromium release CTL assays, and IFN-γ ELISPOT and intracellular flow cytometry assays, are difficult to make reproducible. To address this issue, PBL were obtained from FL patients, cryopreserved, and thawed, then used to design a standardized method for detection of intracellular IFN-γ by flow cytometry. The combined stimulus of soluble anti-CD3 and anti-CD28 antibodies provides a robust stimulation, typically about 5% of normal PBL CD8+ T cells respond. By using a panel of irradiated B cell lymphoma cell lines as stimulators, we demonstrated that, on average, 1 – 2% of these T cells were capable of mounting a response in this assay. Surprisingly, CD8+ PBL T cells from several patients with FL were more responsive to combined anti-CD3 and anti-CD28 stimulation as well as to allo-stimulation, 15 – 22% and 2 – 6%, respectively. This response was accompanied by surface expression of CD107, a surrogate marker for CTL degranulation, in the same population of cells as demonstrated by multi-color flow cytometry. Both the IFN-γ and the CD107 responses were inhibited by an anti-class I antibody, W6/32, suggesting a class I restricted T cell receptor-mediated response. Furthermore, at later time points, these T cells also up-regulated CD137 on their surface. This activation molecule is upregulated on CD8 T cells in response to specific antigen recognition and provides an anti-apoptotic signal to the cells. In conclusion, immune competency of CD8 T cells isolated from FL patients can be assessed through allo-stimulation by a panel of B cell lymphoma cell lines. More importantly, correlation by flow cytometry of 3 independent indicators of response (IFN-γ, CD107 and CD137) within single populations of cells to both allo-stimulation and to the specific target, may lead to better understanding of the role of T cells in the immune response. Ultimately, these responses will need to be validated with patient outcomes in clinical trials of vaccines in lymphoma.

scholarly journals Dual T cell– and B cell–intrinsic deficiency in humans with biallelic RLTPR mutations

2016 ◽  
Vol 213 (11) ◽  
pp. 2413-2435 ◽  
Author(s):  
Yi Wang ◽  
Cindy S. Ma ◽  
Yun Ling ◽  
Aziz Bousfiha ◽  
Yildiz Camcioglu ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
B Cells ◽  
B Cell ◽  
Cd4 T Cells ◽  
Ex Vivo ◽  
Cell Phenotype ◽  
Loss Of Function ◽  
Inborn Errors

Combined immunodeficiency (CID) refers to inborn errors of human T cells that also affect B cells because of the T cell deficit or an additional B cell–intrinsic deficit. In this study, we report six patients from three unrelated families with biallelic loss-of-function mutations in RLTPR, the mouse orthologue of which is essential for CD28 signaling. The patients have cutaneous and pulmonary allergy, as well as a variety of bacterial and fungal infectious diseases, including invasive tuberculosis and mucocutaneous candidiasis. Proportions of circulating regulatory T cells and memory CD4+ T cells are reduced. Their CD4+ T cells do not respond to CD28 stimulation. Their CD4+ T cells exhibit a "Th2" cell bias ex vivo and when cultured in vitro, contrasting with the paucity of "Th1," "Th17," and T follicular helper cells. The patients also display few memory B cells and poor antibody responses. This B cell phenotype does not result solely from the T cell deficiency, as the patients’ B cells fail to activate NF-κB upon B cell receptor (BCR) stimulation. Human RLTPR deficiency is a CID affecting at least the CD28-responsive pathway in T cells and the BCR-responsive pathway in B cells.

Vaccine-elicited CD4 T cells prevent the deletion of antiviral B cells in chronic infection

2021 ◽  
Vol 118 (46) ◽  
pp. e2108157118
Author(s):  
Kerstin Narr ◽  
Yusuf I. Ertuna ◽  
Benedict Fallet ◽  
Karen Cornille ◽  
Mirela Dimitrova ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
B Cells ◽  
B Cell ◽  
Cd4 T Cells ◽  
Memory B Cells ◽  
Type I ◽  
Clonal Deletion ◽  
Cell Immunity ◽  
B Cell Immunity

Chronic viral infections subvert protective B cell immunity. An early type I interferon (IFN-I)–driven bias to short-lived plasmablast differentiation leads to clonal deletion, so-called “decimation,” of antiviral memory B cells. Therefore, prophylactic countermeasures against decimation remain an unmet need. We show that vaccination-induced CD4 T cells prevented the decimation of naïve and memory B cells in chronically lymphocytic choriomeningitis virus (LCMV)-infected mice. Although these B cell responses were largely T independent when IFN-I was blocked, preexisting T help assured their sustainability under conditions of IFN-I–driven inflammation by instructing a germinal center B cell transcriptional program. Prevention of decimation depended on T cell–intrinsic Bcl6 and Tfh progeny formation. Antigen presentation by B cells, interactions with antigen-specific T helper cells, and costimulation by CD40 and ICOS were also required. Importantly, B cell–mediated virus control averted Th1-driven immunopathology in LCMV-challenged animals with preexisting CD4 T cell immunity. Our findings show that vaccination-induced Tfh cells represent a cornerstone of effective B cell immunity to chronic virus challenge, pointing the way toward more effective B cell–based vaccination against persistent viral diseases.

scholarly journals Accelerated, but not conventional, radiotherapy of murine B-cell lymphoma induces potent T cell–mediated remissions

2018 ◽  
Vol 2 (19) ◽  
pp. 2568-2580 ◽  
Author(s):  
Suparna Dutt ◽  
Michelle B. Atallah ◽  
Yoshitaka Minamida ◽  
Alexander Filatenkov ◽  
Kent P. Jensen ◽  
...  
Keyword(s):  
T Cells ◽  
Dendritic Cells ◽  
T Cell ◽  
B Cell ◽  
Cd8 T Cells ◽  
Hematopoietic Cell Transplantation ◽  
Cell Lymphoma ◽  
B Cell Lymphoma ◽  
Tumor Irradiation ◽  
Total Radiation Dose

Abstract Conventional local tumor irradiation (LTI), delivered in small daily doses over several weeks, is used clinically as a palliative, rather than curative, treatment for chemotherapy-resistant diffuse large B-cell lymphoma (DLBCL) for patients who are ineligible for hematopoietic cell transplantation. Our goal was to test the hypothesis that accelerated, but not conventional, LTI would be more curative by inducing T cell–mediated durable remissions. We irradiated subcutaneous A20 and BL3750 lymphoma tumors in mice with a clinically relevant total radiation dose of 30 Gy LTI, delivered in 10 doses of 3 Gy over 4 days (accelerated irradiation) or as 10 doses of 3 Gy over 12 days (conventional irradiation). Compared with conventional LTI, accelerated LTI resulted in more complete and durable tumor remissions. The majority of these mice were resistant to rechallenge with lymphoma cells, demonstrating the induction of memory antitumor immunity. The increased efficacy of accelerated LTI correlated with higher levels of tumor cell necrosis vs apoptosis and expression of “immunogenic cell death” markers, including calreticulin, heat shock protein 70 (Hsp70), and Hsp90. Accelerated LTI–induced remissions were not seen in immunodeficient Rag-2−/− mice, CD8+ T-cell–depleted mice, or Batf-3−/− mice lacking CD8α+ and CD103+ dendritic cells. Accelerated, but not conventional, LTI in immunocompetent hosts induced marked increases in tumor-infiltrating CD4+ and CD8+ T cells and MHCII+CD103+CD11c+ dendritic cells and corresponding reductions in exhausted PD-1+Eomes+CD8+ T cells and CD4+CD25+FOXP3+ regulatory T cells. These findings raise the possibility that accelerated LTI can provide effective immune control of human DLBCL.

Terminal plasmocytoid differentiation of malignant B cells induced by autotumor-reactive CD4+ T cells in one case of splenic marginal zone B-cell lymphoma

Blood ◽  
2002 ◽  
Vol 99 (1) ◽  
pp. 388-390 ◽  
Author(s):  
Thierry Bonnefoix ◽  
Jian-Qing Mi ◽  
Pascal Perron ◽  
Mary Callanan ◽  
Cosima Semoun ◽  
...  
Keyword(s):  
T Cells ◽  
B Cells ◽  
B Cell ◽  
Cd4 T Cells ◽  
Marginal Zone ◽  
Cell Lymphoma ◽  
B Cell Lymphoma

scholarly journals Functional analysis of clinical response to low-dose IL-2 in patients with refractory chronic graft-versus-host disease

2019 ◽  
Vol 3 (7) ◽  
pp. 984-994 ◽  
Author(s):  
Jennifer S. Whangbo ◽  
Haesook T. Kim ◽  
Sarah Nikiforow ◽  
John Koreth ◽  
Ana C. Alho ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Graft Versus Host Disease ◽  
Cd8 T Cells ◽  
Cd4 T Cells ◽  
Low Dose ◽  
B Cell Lymphoma ◽  
Host Disease ◽  
Graft Versus Host ◽  
Response Groups

Abstract Patients with chronic graft-versus-host disease (cGVHD) have a paucity of regulatory CD4 T cells (CD4Tregs) that mediate peripheral tolerance. In clinical trials, daily low-dose interleukin-2 (IL-2) has been administered safely for prolonged periods in patients with steroid-refractory cGVHD. Peripheral CD4Tregs expand dramatically in all patients during IL-2 therapy but clinical improvement was observed in ∼50% of patients. Here, we examined the impact of low-dose IL-2 therapy on functional T-cell markers and the T-cell repertoire within CD4Tregs, conventional CD4 T cells (CD4Tcons), and CD8+ T cells. IL-2 had profound effects on CD4Tregs homeostasis in both response groups including selective expansion of the naive subset, improved thymic output, and increased expression of Ki67, FOXP3, and B-cell lymphoma 2 within CD4Tregs. Similar changes were not seen in CD4Tcons or CD8 T cells. Functionally, low-dose IL-2 enhanced, in vitro, CD4Treg-suppressive activity in both response groups, and all patient CD4Tcons were similarly suppressed by healthy donor CD4Tregs. High-throughput sequencing of the T-cell receptor β (TCRβ) locus demonstrated that low-dose IL-2 therapy increased TCR repertoire diversity and decreased evenness within CD4Tregs without affecting CD4Tcons or CD8 T cells. Using clone-tracking analysis, we observed rapid turnover of highly prevalent clones in CD4Tregs as well as the conversion of CD4Tcons to CD4Tregs. After 12 weeks of daily IL-2, clinical responders had a greater influx of novel clones within the CD4Treg compartment compared with nonresponders. Further studies to define the function and specificity of these novel CD4Treg clones may help establish the mechanisms whereby low-dose IL-2 therapy promotes immune tolerance.

A Detailed Phenotypic Analysis Using Six Color Flow Cytometry of Lymphocyte Subsets Mobilized with AMD3100 Compared to G-CSF.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 408-408 ◽  
Author(s):  
Yoshiyuki Takahashi ◽  
S. Chakrabarti ◽  
R. Sriniivasan ◽  
A. Lundqvist ◽  
E.J. Read ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
T Cells ◽  
T Cell ◽  
B Cells ◽  
Cd8 T Cells ◽  
Cd4 T Cells ◽  
Lymphocyte Subsets ◽  
Phenotypic Analysis ◽  
Color Flow ◽  
Cd34 Cells

Abstract AMD3100 (AMD) is a bicyclam compound that rapidly mobilizes hematopoietic progenitor cells into circulation by inhibiting stromal cell derived factor-1 binding to its cognate receptor CXCR4 present on CD34+ cells. Preliminary data in healthy donors and cancer patients show large numbers of CD34+ cells are mobilized following a single injection of AMD3100. To determine whether AMD3100 mobilized cells would be suitable for allografting, we performed a detailed phenotypic analysis using 6 color flow cytometry (CYAN Cytometer MLE) of lymphocyte subsets mobilized following the administration of AMD3100, given as a single 240mcg/kg injection either alone (n=4) or in combination with G-CSF (n=2: G-CSF 10 mcg/kg/day x 5: AMD3100 given on day 4). Baseline peripheral blood (PB) was obtained immediately prior to mobilization; in recipients who received both agents, blood was analyzed 4 days following G-CSF administration as well as 12 hours following administration of AMD3100 and a 5th dose of G-CSF. AMD3100 alone significantly increased from baseline the PB WBC count (2.8 fold), Absolute lymphocyte count (ALC: 2.5 fold), absolute monocyte count (AMC: 3.4 fold), and absolute neutrophil count (ANC: 2.8 fold). Subset analysis showed AMD3100 preferentially increased from baseline PB CD34+ progenitor counts (5.8 fold), followed by CD19+ B-cells (3.7 fold), CD14+ monocytes (3.4 fold), CD8+ T-cells (2.5 fold), CD4+ T-cells (1.8 fold), with a smaller increase in CD3−/CD16+ or CD56+ NK cell counts (1.6 fold). There was no change from baseline in the % of CD4+ or CD8+ T-cell expressing CD45RA, CD45RO, or CD56, CD57, CD27, CD71 or HLA-DR. In contrast, there was a decline compared to baseline in the mean percentage of CD3+/CD4+ T-cells expressing CD25 (5.5% vs 14.8%), CD62L (12.1% vs 41.1%), CCR7 (2.1% vs 10.5%) and CXCR4 (0.5% vs 40.9%) after AMD3100 administration; similar declines in expression of the same 4 surface markers were also observed in CD3+/CD8+ T-cells. A synergistic effect on the mobilization of CD34+ progenitors, CD19+ B cells, CD3+ T-cells and CD14+ monocytes occurred when AMD3100 was combined with G-CSF (Figure). In those receiving both AMD3100 and G-CSF, a fall in the % of T-cells expressing CCR7 and CXCR4 occurred 12 hours after the administration of AMD3100 compared to PB collected after 4 days of G-CSF; no other differences in the expression of a variety activation and/or adhesion molecules on T-cell subsets were observed. Whether differences in lymphocyte subsets mobilized with AMD3100 alone or in combination with G-CSF will impact immune reconstitution or other either immune sequela (i.e. GVHD, graft-vs-tumor) associated with allogeneic HCT is currently being assessed in an animal model of allogeneic transplantation.

Cultured Human B Cell APCs Expanded Using Il-4 and CD40 Ligand Preferentially Promote a Type 2 T Cell Response to Alloimmune Stimulation.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 2668-2668
Author(s):  
Abdul Tawab ◽  
Yoshiyuki Takahashi ◽  
Childs Richard ◽  
Kurlander J. Roger
Keyword(s):  
T Cells ◽  
T Cell ◽  
B Cells ◽  
B Cell ◽  
Cell Response ◽  
Cd40 Ligand ◽  
T Cell Response ◽  
Ifn Γ

Abstract In vitro stimulation of human peripheral blood B cells with recombinant IL-4 and CD40 ligand (CD40L) markedly increases their expression of MHC and costimulatory molecules, thus enhancing antigenic peptide presentation to T cells. Because these cells proliferate extensively in vitro (unlike monocytes or dendritic cells), they represent a promising and convenient reagent for the generation and maintenance of antigen-specific T cells for use in a variety of experimental or therapeutic settings. However, the impact of this type of B cell APC on cytokine production by responder T cells has hitherto not been examined. To address this issue, we stimulated normal human T cells with either allogeneic B cells (generated in vitro) or with MNCs obtained from the same donor. After 7 days, T cells were washed and re-challenged with the same APCs. The resulting alloreactive cytokine response was measured using quantitative ELISPOT methods and expressed as the frequencies of IFN-γ, IL-4, and IL-5 producing cells per thousand responder cells added. B cell- and MNC-primed cell lines both produced vigorous lymphokine responses, but B cell-stimulated T cells consistently produced more IL-5 spots (mean of 265 vs. 98/1000 responders, p<0.002) and fewer IFN-γ spots (163 vs 386/1000 cells, p<0.005) than MNC-stimulated cells. Further, the ratio of IFN-γ to IL-5 spots was almost ten-fold lower in B cell-stimulated cultures compared to MNC-induced cultures (0.67 vs. 5.2, p<0.001). ELISPOT studies assessing the ratio of IFN-γ to IL-4 spots and ELISA assays comparing IFN-γ and IL-5 levels from culture supernatants demonstrated the same pattern of marked type 2 skewing by B cells. This pattern was unaffected by the presence of anti-IL-4 antibody suggesting type 2 skewing was not mediated by IL-4. Cytokine skewing produced by B cells or MNC could be partially reversed by swapping MNC and B cells during re-stimulation on day 7, but this plasticity was markedly reduced after 3 (weekly) cycles of B cell or MNC re-stimulation in vitro. Type 2 skewing by B cells was enhanced when monocytes were removed from responder T cell populations by either depleting CD14+ positive cells or by positive selection of T cells prior to stimulation. In contrast, type 2 polarization could be prevented using recombinant IL-12. Not all cells of B-cell origin share the same propensity to type 2 skewing observed with IL-4/CD40L-stimulated B cells; under identical conditions, EBV-transformed B cells stimulated alloimmune T cells to produce a strong type 1 cytokine response comparable to that produced by MNCs. In summary, IL-4/CD40L-stimulated B cells strongly promote a type 2 T cell response during primary alloimmune challenge; this skewing can become fixed after repeated B cell stimulation. Investigators using these cells as APC should be aware of this potential phenomenon, particularly during primary T cell responses. It is also important to consider the factors described above that may exacerbate or ameliorate this effect.

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