Intrinsic AHR in IL-5 transgenic mice is dependent on CD4+ cells and CD49d-mediated signaling

2001 ◽  
Vol 281 (3) ◽  
pp. L653-L659 ◽  
Author(s):  
Michael T. Borchers ◽  
J. Crosby ◽  
P. Justice ◽  
S. Farmer ◽  
E. Hines ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Transgenic Mice ◽  
B Cell ◽  
Airway Epithelium ◽  
Airway Hyperreactivity ◽  
Integrin Signaling ◽  
Cd4 Cells

Overexpression of interleukin (IL)-5 by the airway epithelium in mice using the rat CC10 promoter (NJ.1726 line) leads to several histopathologies characteristic of human asthma, including airway hyperreactivity (AHR). We investigated the contribution of B and T cells, as well as CD4 expression, to the development of AHR in IL-5 transgenic mice. NJ.1726 mice on a T cell or CD4 knockout background, but not on a B cell knockout background, lost intrinsic AHR. These effects occurred without decreases in IL-5 or eosinophils. We further investigated the contribution of α4-integrin signaling to the development of AHR in IL-5 transgenic mice through the administration of anti-CD49d (α4-integrin) antibody (PS/2). Administration of PS/2 resulted in immediate (16-h) inhibition of AHR. The inhibition of AHR was not associated with a decrease in airway eosinophils. These studies demonstrate that, despite the presence of increased levels of IL-5 and eosinophils in the lungs of NJ.1726 mice, CD4+ cells and α4-integrin signaling are necessary for the intrinsic AHR that develops in IL-5 transgenic mice.

Distinct Patterns of Systemic Immune Dysregulation in Indolent B Cell Lymphoma

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 3780-3780
Author(s):  
Petros Christopoulos ◽  
Dietmar Pfeifer ◽  
Kilian Bartholomé ◽  
Marie Follo ◽  
Paul Fisch ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
B Cell ◽  
T Cell Activation ◽  
Cell Activation ◽  
Immune Dysregulation ◽  
Cell Phenotype ◽  
Cd4 Cells ◽  
Th Cells

Abstract Mutual interactions of the neoplastic clone with the non-neoplastic immune system may influence immune function and the clinical behaviour of lymphoma. Individuals with immunodeficiency or autoimmune diseases have an increased risk for lymphoma development. The immune microenvironment appears to have a major influence on the prognosis of indolent lymphomas. Conversely, leukemic lymphomas may also cause immunodeficiency: In CLL, direct lymphoma-T cell interactions, which may occur ubiquitously, induce defects in T cell functions (Görgün et al., 2005). We demonstrate here a systemic perturbance of cellular immunity in a prospective study in patients with untreated de novo, limited-stage, non-leukemic indolent B cell lymphomas. Calibrated, quantitative flow cytometry showed a significant reduction of circulating T helper (TH) cells in follicular (FL; n=11; p<0.005) and extranodal marginal zone (eMZL; n=7; p<0.05) lymphomas compared to age-matched healthy persons. Naive TH cells were strongest reduced to 51% (p=0.002) in FL and 24% (p=0.002) in eMZL. Regulatory T cells (CD4loCD25hi; CD4+FoxP3+) were affected less (p=0.04). T cell receptor excision circles within CD4+ cells as assessed by quantitative PCR were not altered in lymphoma patients, indicating neither increased increased thymic output nor homeostatic T cell proliferation to compensate the contracted pool of naive T cells. The TH memory compartments, the global numbers and subsets of CD8+ T (TC) cells, NK, and NKT cells were normal. The peripheral lymphocyte composition was altered differently in early CLL (stage Binet A; leukocyte counts < 28/nl; n=9) with increased TH (p=0.04) and TC (p=0.0002) cells. No significant changes in lymphocyte subsets were noted in monoclonal gammopathy of unknown significance (MGUS; n=6). The functional T cell phenotype in vivo was altered in eMZL as indicated by four- and twofold increased HLA-DR+ TH (p<0.02) and TC (p=0.05) cells. This T cell activation may also explain an increased fraction of terminally differentiated (CD45RA+CD27−) TC cells (p<0.05). Qualitatively similar abnormalities were seen in FL, where activated TH cells were more frequent (p<0.005), and in CLL, where activated TC cells were increased (p=0.04), but not in MGUS. Finally, an increased T cell activation may effect senescence, which was evident by elevated fractions of CD57+ and CD28− cells within the TC compartment of FL/eMZL (p<0.05) and CLL (p<0.005) patients. The activated T cell phenotype was paralleled by increased upregulation of activation markers (CD25, OX40, CD95, p<0.005 for each) and proliferation (p<0.005) by purified CD4 cells from FL/eMZL patients in a standardized anti-CD3/anti-CD28 stimulation culture. None of these parameters was significantly aberrant in CLL. Expression of the activation marker CD69, which is downregulated rapidly after T cell activation, was markedly reduced both in vivo and after in vitro stimulation in FL/eMZL. Collectively, these data demonstrate a global, “preactivated” and presenescent state of peripheral T cells in non-leukemic, indolent T cell lymphomas. Finally, a shift towards TH2 cells was evident in FL/eMZL TH stimulation cultures by increased secretion of IL-4 and IL-5 (p=0.01), but not of IL-2, IFNg, IL-10, and TNFa. This cytokine pattern was absent in CLL and MGUS. The TH2 shift, and the qualitative difference in the immune status in FL/eMZL versus CLL was validated by gene expression profiling of stimulated TH cells with Affymetrix U133 arrays. KEGG annotation revealed decreased expression of proximal TCR signalling molecules and TCR/CD28 transduction pathways with the exception of NFAT in FL/eMZL and CLL. Extensive correlative analyses between gene expression profiles and functional data indicated at least two distinct immune dysregulation patterns: A hyperreactivity/TH2 pattern which is operational even in early disease; and a B cell burden-dependent impairment of TCR signalling. The latter pattern predominates in CLL, which has a comparatively high B cell burden in early disease. These data are clinically relevant since we demonstrate in a prospective trial that untreated FL/eMZL patients fail to respond to protective hepatitis B vaccination (p<0.005). Precise definition of functional T cell defects will permit to study the causes, the prognostic influence, and potential reversibility of immune dysregulation patterns in indolent B cell lymphomas.

scholarly journals Spontaneous relapsing-remitting EAE in the SJL/J mouse: MOG-reactive transgenic T cells recruit endogenous MOG-specific B cells

2009 ◽  
Vol 206 (6) ◽  
pp. 1303-1316 ◽  
Author(s):  
Bernadette Pöllinger ◽  
Gurumoorthy Krishnamoorthy ◽  
Kerstin Berer ◽  
Hans Lassmann ◽  
Michael R. Bösl ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
B Cells ◽  
Transgenic Mice ◽  
B Cell ◽  
Cell Receptor ◽  
Conformational Epitope ◽  
Autoreactive B Cells ◽  
Spinal Cord Development ◽  
Relapsing Remitting

We describe new T cell receptor (TCR) transgenic mice (relapsing-remitting [RR] mice) carrying a TCR specific for myelin oligodendrocyte glycoprotein (MOG) peptide 92–106 in the context of I-As. Backcrossed to the SJL/J background, most RR mice spontaneously develop RR experimental autoimmune encephalomyelitis (EAE) with episodes often altering between different central nervous system tissues like the cerebellum, optic nerve, and spinal cord. Development of spontaneous EAE depends on the presence of an intact B cell compartment and on the expression of MOG autoantigen. There is no spontaneous EAE development in B cell–depleted mice or in transgenic mice lacking MOG. Transgenic T cells seem to expand MOG autoreactive B cells from the endogenous repertoire. The expanded autoreactive B cells produce autoantibodies binding to a conformational epitope on the native MOG protein while ignoring the T cell target peptide. The secreted autoantibodies are pathogenic, enhancing demyelinating EAE episodes. RR mice constitute the first spontaneous animal model for the most common form of multiple sclerosis (MS), RR MS.

scholarly journals Bone Marrow and Thymus Expression of Interferon-γ Results in Severe B-Cell Lineage Reduction, T-Cell Lineage Alterations, and Hematopoietic Progenitor Deficiencies

Blood ◽  
1997 ◽  
Vol 89 (2) ◽  
pp. 583-595 ◽  
Author(s):  
Howard A. Young ◽  
Dennis M. Klinman ◽  
Della A. Reynolds ◽  
Krzysztof J. Grzegorzewski ◽  
Aisuke Nii ◽  
...  
Keyword(s):  
Bone Marrow ◽  
T Cells ◽  
T Cell ◽  
Transgenic Mice ◽  
B Cell ◽  
Cell Lineage ◽  
Interferon Γ ◽  
Ifn Γ ◽  
B Lineage ◽  
Spleen And Lymph Nodes

Abstract Interferon-γ (IFN-γ) is an immunoregulatory lymphokine that is primarily produced by T cells and natural killer cells. It has effects on T-cell, B-cell, and macrophage differentiation and maturation. We have developed transgenic mice that express elevated levels of IFN-γ mRNA and protein by inserting multiple copies of murine IFN-γ genomic DNA containing an Ig λ-chain enhancer in the first intron. The founder line carrying eight copies of this transgene has eightfold to 15-fold more IFN-γ–producing cells in the bone marrow and spleen than do nontransgenic littermates. Transgenic mice show a pronounced reduction in B-lineage cells in the bone marrow, spleen, and lymph nodes. In addition, single positive (CD4+,CD8− and CD4−,CD8+) thymocyte numbers are increased twofold, yet the number of splenic T cells is reduced by 50%. There is also a twofold to threefold decrease in the frequency and total number of myeloid progenitors in the bone marrow. Granulomatous lesions and residual degenerating cartilaginous masses are also present in the bones of these mice. Overall, our data show that the abnormal expression of IFN-γ in these transgenic mice results in multiple alterations in the immune system. These animals provide an important model to examine the role of IFN-γ expression on lymphoid and myeloid differentiation and function.

scholarly journals Antibody-mediated B-cell depletion before adoptive immunotherapy with T cells expressing CD20-specific chimeric T-cell receptors facilitates eradication of leukemia in immunocompetent mice

Blood ◽  
2009 ◽  
Vol 114 (27) ◽  
pp. 5454-5463 ◽  
Author(s):  
Scott E. James ◽  
Nural N. Orgun ◽  
Thomas F. Tedder ◽  
Mark J. Shlomchik ◽  
Michael C. Jensen ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
B Cells ◽  
Transgenic Mice ◽  
B Cell ◽  
T Cell Receptors ◽  
Adoptive T Cell Therapy ◽  
Cell Depletion ◽  
B Cell Depletion ◽  
Cell Receptors

Abstract We have established a model of leukemia immunotherapy using T cells expressing chimeric T-cell receptors (cTCRs) targeting the CD20 molecule expressed on normal and neoplastic B cells. After transfer into human CD20 (hCD20) transgenic mice, cTCR+ T cells showed antigen-specific delayed egress from the lungs, concomitant with T-cell deletion. Few cTCR+ T cells reached the bone marrow (BM) in hCD20 transgenic mice, precluding effectiveness against leukemia. Anti-hCD20 antibody-mediated B-cell depletion before adoptive T-cell therapy permitted egress of mouse CD20-specific cTCR+ T cells from the lungs, enhanced T-cell survival, and promoted cTCR+ T cell–dependent elimination of established mouse CD20+ leukemia. Furthermore, CD20-specific cTCR+ T cells eliminated residual B cells refractory to depletion with monoclonal antibodies. These findings suggest that combination of antibody therapy that depletes antigen-expressing normal tissues with adoptive T-cell immunotherapy enhances the ability of cTCR+ T cells to survive and control tumors.

scholarly journals POS0003 RITUXIMAB THERAPY IN SYSTEMIC LUPUS ERYTHEMATOSUS – TRANSIENT EFFECTS ON AGE ASSOCIATED B-CELLS

2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 203.1-204
Author(s):  
F. Faustini ◽  
N. Sippl ◽  
R. Stålesen ◽  
K. Chemin ◽  
I. Gunnarsson ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
B Cells ◽  
B Cell ◽  
T Cell Subsets ◽  
Cd4 Cells ◽  
Helper Cells ◽  
B Cell Subsets ◽  
Anti Cd20

Background:Immune system’s abnormalities in SLE involve several subsets of the B-cell compartment, including double negative B-cells (DN) and CD11c+CD21- B cells (also referred to as ABC-age associated B cells), which are expanded in the disease. ABC cells are also known to interact with T helper cells, T follicular and peripheral helper cells (1). Rituximab, a chimeric anti- CD20 antibody, depleting B cells, is commonly used off-label as treatment for SLE patients, especially in lupus nephritis. Little is known on the impact of B-cell depletion on such B-cell subsets and on B-T-cell interactions.Objectives:to investigate the effects of rituximab (RTX) on the frequencies of double negative B-cell subsets and CD11c+CD21- ABC cells and as well as T follicular helper (TFH, CXCR5+ PD-1+) and T peripheral helper (TPH, PD-1high) CD4+ T-cell subsets.Methods:15 SLE patients, starting RTX and followed longitudinally up to two years, were analyzed for lymphocyte subsets using multicolor flow cytometry. Cryopreserved PBMC were thawed and stained at the same time together with one buffy coat. Around 1 x 106 PBMC for each panel were labeled and further stained with fluorescent antibodies for B and T-cell markers. For the B-cell panel, PBMC were stained with anti-CD3, CD14, CD16, CD19, IgD, CD27, CD38, CD11c, CD21 and in some samples with anti-CXCR5 antibodies. For the T-cell panel, PBMC were labeled with anti-CD16, CD14, CD19 and CD3, CD4, CD8, PD-1, CCR7, CXCR5, CD45RA antibodies. All patients fulfilled the ACR 1982 classification criteria for SLE. Cellular changes were analyzed in the context of clinical information.Results:in the present cohort, the SLE patients were mainly female (86.6%) and of median age of 36.7 (29.8-49.4) with a disease duration of 6.1(1.6-11.8) years, and active disease with SLEDAI-2K at baseline 12.0 (8.0-16.0). The frequency of age-associated B cells (ABCs; CD27-IgD-CD11c+ CD21-) decreased by 13% (p=0.03) in the first two to four months after rituximab start, while globally the DN (IgD-CD27-) B cells transiently increased by around 3% (p=0.15) at the first follow-up. This increase could not be attributed to the DN1 (CXCR5+CD11c-) or DN2 (CXCR5-CD11c+) subsets but to the CD11c-CXCR5- DN (DN3) B cells (increase= 6.7%, p=0.03). In parallel, T effector cells (CCR7- CD45RA+) and TEMRA (CD45RA+ CCR7-) frequencies increased after first follow up in both CD4+ and CD8+ T cells. The frequency of TFH (CXCR5+ PD-1+) cells did not change after rituximab, however a decrease of PD-1high CD4+ cells was observed in most patients, although not significant, after 2-4 month of treatment. In most patients the frequency of PD-1high CD4+ cells either reduce or stay the same after RTX treatment (reduction= 0.53, p=0.28). After 11-15 months of RTX treatment the frequency of PD-1high CD4+ T cell reduces by a -0.5% in comparison to 2-4 months (p=0.039). The SLEDAI at baseline did not correlate with the frequency of PD-1high CD4+ T cells (r=0.03, p=0.9).Conclusion:the importance of T cell - B cell interactions in SLE pathogenesis was recently strengthened by the identification of the lymphocyte subsets TFH/TPH and ABCs respectively. Here, in the context of rituximab treated SLE, we could detect a reduction in the frequencies of both ABCs and PD-1high T cells after treatment with rituximab, while the DN3 and effector memory T cells frequencies increased. Our data suggests that anti-CD20 mediated B-cell depletion affects both B-cell and T-cell subsets frequencies, and that monitoring these specific cell subsets may be clinically relevant.References:[1]Bocharnikov AV, Keegan J, Wacleche VS, Cao Y, Fonseka CY, Wang G, et al. PD-1hiCXCR5- T peripheral helper cells promote B cell responses in lupus via MAF and IL-21. JCI insight. 2019;4(20)Disclosure of Interests:Francesca Faustini Speakers bureau: More than two years ago and not in relation to any aspect of the present research, Natalie Sippl: None declared, Ragnhild Stålesen: None declared, Karine Chemin: None declared, Iva Gunnarsson: None declared, Vivianne Malmström: None declared.

Gene Expression Profiling Identifies Similar CD4+ and CD8+ T Cell Defects in TCL1 Transgenic Mice after Development of CLL to Those Observed in Patients with CLL.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 180-180
Author(s):  
Vassiliki Rizouli ◽  
David Zahrieh ◽  
Gullu Gorgun ◽  
Tobias A.W. Holderried ◽  
Carlo Croce ◽  
...  
Keyword(s):  
Gene Expression ◽  
T Cells ◽  
Cell Differentiation ◽  
T Cell ◽  
Transgenic Mice ◽  
Cd8 T Cells ◽  
Effector Function ◽  
Cd4 Cells ◽  
Cd8 Cells ◽  
The Impact

Abstract The TCL1 gene at 14q32.1 is involved in chromosomal translocations and inversions in T cell leukemias, but targeted expression of the TCL1 gene in mice results in the development of a CLL like disorder in older mice resembling human B-CLL, so that deregulation of the TCL1 pathway proved to play a crucial role in CLL pathogenesis in mice. Development and progression of B-CLL is associated with immune dysregulation and in particular T cell defects. Although patients with CLL often have normal or even increased T cell numbers, there is an abnormal CD4/CD8 ratio, impaired mitogen responses and defective effector function in response to antigenic stimulation. We have previously categorized defects in the gene expression profile of CD4 and CD8 T cells in patients with CLL. We therefore sought to determine if the onset of CLL in the TCL1-transgenic mice also resulted in defects similar to those observed in patients with CLL. The aim was to determine if this murine model would mimic the impact of CLL on the normal immune system, so that we could use this model to examine in vivo the impact of steps taken to repair T cell defects. To examine this, we highly purified CD4 and CD8 T cells by positive selection from non-transgenic mice and TCL1 transgenic mice of different ages and at different stages in disease development. Total RNA was extracted, cRNA synthesized, labeled and hybridized to the Mouse 430_2 Affymetrix chip. We used DNA-Chip Analyzer (dChip) to perform an unsupervised analysis, which consisted of gene filtering, excluding genes that lacked sufficient variability across groups, and hierarchical clustering of genes and samples. This type of analysis demonstrated that CD4 and CD8 T cells of young mice without CLL clustered with non-transgenic mice of different ages, but separately from CD4 and CD8 cells from mice with developing and established CLL. Supervised analysis using Permax of the gene expression profiles of T cells in non-transgenic mice and non-tumor bearing TCL1 mice compared to CLL bearing mice identified significant differences in expression for 348 in CD4 cells and 127 genes for CD8 cells. In CD4 cells from CLL mice 202 genes were upregulated and 146 were downregulated and in CD8 cells 32 genes were upregulated and 95 genes downregulated. Analysis of the genes observed to be altered in the CLL bearing mice revealed that the majority were involved in genes regulating cytoskeleton formation, intracellular transportation, vesicle formation and transport, cell cycle control and cell differentiation. Comparison of the pathways perturbed in the mice compared to that observed in our previous study in patients with CLL demonstrated alteration in many similar pathways. The findings in human and murine CLL are in keeping with the hypothesis that interaction of the CLL cells with the normal immune function induces changes that result in decrease in T cell differentiation and effector function. It is intriguing to postulate that this effect would diminish autologous anti-tumor responses. We conclude that development of CLL in these transgenic mice induces T cell defects that mimic the defects that occur in CLL patients and that the TCL1 transgenic mouse model will serve as an ideal model to study steps to repair T cell function and their impact on CLL.

Clonal Diversity of the T Cell Repertoire Predicts Disease Progression in Chronic Lymphocytic Leukaemia

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 803-803
Author(s):  
Claudia Holler ◽  
Nadja Zaborsky ◽  
Josefina Pinon Hofbauer ◽  
Thomas Kocher ◽  
Doris Trapin ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
B Cell ◽  
Lymphocytic Leukaemia ◽  
Cd4 T Cell ◽  
T Cell Repertoire ◽  
Cd4 Cells ◽  
Cell Repertoire ◽  
Cell Diversity ◽  
Selection Of

Abstract Abstract 803 Introduction: The development of B cell chronic lymphocytic leukaemia (CLL) involves antigenic selection of the B cell clone, as evidenced by a skewed BCR repertoire found in CLL cells, as well as continuing BCR signaling detected in subgroups of CLL. T cell involvement in the maintenance of the malignant clone is also suggested by a number of evidential lines, such as the severe skewing of T cell subsets in CLL and the presence of relevant numbers of CD4 cells in the so-called “proliferation centers” in lymph nodes. However, neither clonal nor immunologic identities of these T cells have been sufficiently determined. Recently, we have shown in Tcl1 transgenic mice that CLL clones were able to directly drive changes in the T cell repertoire, resulting in relatively fast skewing in subset distribution (similar to that observed in human CLL) as well as a clonal selection of T cells, both in spontaneously developing CLL in the model, as well as in immunocompetent congenic recipient mice in experiments transplanting established murine CLL. Methods: To establish evidence for similar interactions in human CLL, we collected a descriptive database determining patterns of T cell diversity in CLL patient blood. We analyzed T cells from 53 previously-untreated CLL patients established TCR V beta clonality and frequency based on CDR3 length polymorphism in sorted CD4 cells and, in a confirmatory subset, based on TCR V gene-specific flow cytometry. CLL samples were also investigated regarding the BCR VH gene usage, mutation status and clinical and prognostic parameters. Results: BCR analysis confirmed antigenic selection in our patient set with 6 IgVH genes accounting for > 50% of the cases. Stereotyped CDR3 regions were common and one third of the patients showed unmutatetd IgVH gene sequence. Analysing 20 TCR genes by PCR spectratyping, the TCR CDR3 size distribution pattern revealed a relevant frequency of oligoclonal/monoclonal CD4 T cells in CLL samples. While a number of patients showed completely polyclonal patterns in all their TCR CDR3 regions, others showed either single or multiple clonal TCR families. In corresponding flow cytometric analyses clonal T cells could make up to 48% of total CD4 cells in a given patient. In patients with longitudinal samples we found relevant stability of these TCR patterns over time. By comparing the data from the TCR clonality database with our BCR dataset we established that these clonal patterns significantly, but not exclusively, clustered in unmutated patient samples. Overall we found no strong association with any specific IgVH gene, but intriguingly, in some patients a specific clonal TCR corresponded to a stereotyped BCR receptor. In fact in two patient pairs with identical IgVH rearrangements we found corresponding TCR clones that showed sequence identity between the CD4 T cell clones derived from the other patient. In addition in both pairs we found a shared HLA DR and DQ haplotype. These data strongly suggests that there may be an important link between the antigenic selection on the B-CLL clone and the selection of certain TCR clones, thus for the first time postulating an antigentic identity of the CLL-associated T cells. This proposed identity, however, currently remains unclear. Finally, we tested for an influence of T cell clonality on clinical behaviour of CLL disease in the patients. We could intentify the presence of more than one clonal TCR family as a significant predictor of a short treatment-free interval (p=0.03). This was true for both, patients with mutated and unmutated IgVH receptors, although it remained a trend in the latter. Conclusion: Our results imply that a restricted CD4 T cell diversity may be important for CLL progression and that an as of yet still undefined antigenic drive for T cells may be important for this. This may help to define specific monoclonal CD4 T cells as a promising novel target for future therapeutic intervention. Disclosures: No relevant conflicts of interest to declare.

scholarly journals B cell function in mice transgenic for mCTLA4-H gamma 1: lack of germinal centers correlated with poor affinity maturation and class switching despite normal priming of CD4+ T cells.

1994 ◽  
Vol 179 (3) ◽  
pp. 819-830 ◽  
Author(s):  
P Lane ◽  
C Burdet ◽  
S Hubele ◽  
D Scheidegger ◽  
U Müller ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
B Cells ◽  
Transgenic Mice ◽  
B Cell ◽  
Germinal Center ◽  
Cd4 T Cells ◽  
Class Switching ◽  
T Cell Help ◽  
Germinal Center Formation

This report outlines the B cell phenotype of transgenic mice that overexpresses the mouse CTLA-4-human gamma 1 (mCTLA4-H gamma 1) protein. Despite the fact that these mice prime CD4+ T cells (Ronchese, F., B. Housemann, S. Hubele, and P. Lane. 1994. J. Exp. Med. 179:809), antibody responses to T-dependent antigens are severely impaired. In contrast, T-independent responses are normal which suggests mCTLA4-H gamma 1 does not act directly on B cells, but acts indirectly by impairing T cell help. The impaired antibody defect is associated with impaired class switching, with low total immunoglobulin (Ig)G and antigen-specific IgG responses, and an absence of germinal center formation in spleen and lymph nodes but not gut-associated tissues. The defective germinal center formation is associated with a reduction in the degree of somatic mutation in hybridomas made from transgenic mice in comparison with those made from normal mice. It seems likely that mCTLA4-H gamma 1 exerts its effect by blocking an interaction between T and B cells that induce T cell help for B cells.

CLL Cells in TCL1 Transgenic Mice Induce Similar Defects in CD4 and CD8 T Cells to Those Observed in Patients with CLL.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 50-50
Author(s):  
Gullu Gorgun ◽  
Tobias A.W. Holderried ◽  
Rifca Ledieu ◽  
David Zahrieh ◽  
John G. Gribben
Keyword(s):  
T Cells ◽  
T Cell ◽  
Transgenic Mice ◽  
Cd8 T Cells ◽  
Cell Function ◽  
Cd4 Cells ◽  
Cd8 Cells ◽  
The Impact ◽  
Young Mice

Abstract Deregulation of the TCL1 pathway plays a crucial role in B-CLL pathogenesis and targeted expression of TCL1 results in the development in older mice of a B cell lymphoproliferative disorder resembling human B-CLL. CLL patients develop progressively impaired immunity and gene expression profiling of CD4 and CD8 T cells in B-CLL patients revealed defects in genes regulating critical pathways for T cell effector function. The onset of CLL in TCL1-transgenic mice also results in defects similar to those observed in CLL patients. Therefore, this murine model mimics the impact of CLL on the normal immune system, suggesting this may be an appropriate model to examine in vivo the impact of steps taken to repair T cell defects. In this study we examined whether infusion of CLL cells obtained from older mice induced similar changes in T cells of young mice, providing direct demonstration in vivo of interactions of CLL cells with the host immune system which result in development of immune deficiencies. Global gene expression profiling was performed using the Mouse 430_2 Affymetrix chip on highly purified CD4 and CD8 T cells from 6 non-transgenic mice and 16 TCL1 transgenic mice of different ages and at different stages in disease development and compared to that of cells from 6 TCL1 transgenic mice without CLL injected one week previously with 50 x 106 CLL cells. On unsupervised analysis using DNA-Chip Analyzer CD4 and CD8 T cells of young mice without CLL clustered with non-transgenic mice of different ages, whereas CD4 and CD8 cells from mice with developing or established CLL clustered with the young mice injected with CLL cells. Supervised analysis using Permax identified significant differences in expression for 628 genes (125 genes upregulated and 503 downregulated) in CD4 cells and 620 genes (320 genes upregulated and 300 genes downregulated) in CD8 cells in T cells from CLL bearing mice and CLL cell injected mice compared to non-transgenic mice and non-tumor bearing TCL1 mice. Comparison of pathways perturbed in the mice using GenMAPP finder compared to that observed in our previous studies in patients with CLL demonstrates similar alteration in many pathways, including regulation of cell proliferation and cell cycle control, cell differentiation, cytoskeleton formation, intracellular transportation and vesicle formation and transport. Examining these pathways functionally, we observed significantly decreased T cell proliferation, cytotoxicity and helper T cell function, increased numbers of CD4+CD25+CTLA4+ regulatory T cells and increased IL-4 amd IL-13 and decreased IL-12, IFNγ, sTNFRI, sTNFRII in CD4 cells and decreased IL-12p40, TIMP1 and TIMP2 in CD8 cells in both CLL bearing mice or mice injected with CLL cells compared to mice without CLL. These similar findings in human and murine CLL are in keeping with the hypothesis that interaction of the CLL cells with the normal immune function induces changes that result in decrease in T cell differentiation and effector function. It is intriguing to postulate that this effect diminishes autologous anti-tumor responses. We conclude that development of CLL in these transgenic mice induces T cell defects that mimic the defects that occur in CLL patients and that the TCL1 transgenic mouse model will serve as an ideal model to study steps to repair T cell function and their impact on CLL.

T Cell Dynamics during the Pretumor and Tumor Phase in the Murine Tcl1 Transgenic Chronic Lymphocytic Leukemia Model

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 3145-3145
Author(s):  
Alexander Egle ◽  
Josefina D. Pinon ◽  
Christoph Heyder ◽  
Claudia Holler ◽  
Ursula Denk ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
B Cells ◽  
Transgenic Mice ◽  
B Cell ◽  
Peritoneal Cavity ◽  
Memory T Cells ◽  
Effector T Cells ◽  
Cell Compartment ◽  
Cell Pool

Abstract Chronic lymphocytic leukaemia of B cells (B-CLL) is characterised by a clonal expansion of CD5-expressing B cells. However, the absolute number of T cells in patients with B-CLL is also increased, primarily due to an enlarged CD8+ population. Despite the enhanced number of T cells, they appear to be dysfunctional as they are largely devoid of anti-tumor activity and may even support the growth and maintenance of the malignant B-CLL clone. To further investigate the contribution this T cell dysfunction has on the establishment and progression of B-CLL, we monitored the changes in the T cell compartment in Eμ-TCL1 transgenic mice of various ages, during the progression of B-CLL-like disease. The deregulated expression of TCL1 in the B cell compartment of these mice leads to a hyperplasia of CD5+ CD19+ B cells early in life that is first detectable in the peritoneal cavity and later spleen and bone marrow. Later, this develops into a clonal disease, and onset of frank leukaemia, with infiltration of the CD5+ CD19+ cells into other organs (Bichi et al, 2003). Similar to human B-CLL, leukaemic TCL1 transgenic mice have increased absolute numbers of T cells, owing mainly to an expanded CD8+ population. Analyses of the cell surface expression of CD25, CD44, and CD62L, revealed a marked increase the number of memory and effector T cells compared to naïve T cells in the CD8+ subset that is also observed in the CD4+ subset, although to a lesser degree. Importantly, a decrease in the number of naïve T cells along with a corresponding increase in T memory and effector cells has been observed in the CD4+ T cell pool from patients with unmutated B-CLL (Tinhofer et al, unpublished), and the TCL1 mouse has been shown to be a model for the unmutated form of B-CLL. The relative shift from naïve to central memory T cells occurs alongside the CD5+ CD19+ hyperplasia in the TCL1 mice. In younger mice that exhibit the CD5+ CD19+ hyperplasia only in the peritoneal cavity, the changes in the T cell compartment are also observed solely within this organ. At later stages, when the CD5+ CD19+ hyperplasia has spread to other organs, the shift to memory T cells is also detectable in all infiltrated organs. Because memory and effector T cells represent antigen-experienced cells, we analysed the complementarity determining region 3 (CDR3) of the T cell receptor (TCR) of purified CD4+ and CD8+ populations by spectratyping in order to determine the degree of clonality (mono-, oligo-, or polyclonal) of the different T cell families within the T cell pool. More clonal T cells were observed in the CD8+ T cell subset in the infiltrated organs of leukaemic mice, though we could not observe a skewing towards any particular BV gene family. Interestingly, more mono- and oligoclonal CD4+ T cells have also been observed in the peripheral blood of patients with unmutated B-CLL. Thus, in many aspects, the TCL1 mouse recapitulates many of the T cell abnormalities observed in patients with B-CLL. It should be noted that, although driven from a B-cell specific promoter, the hTCL1 transgene is also expressed in the T cells of TCL1 mice. Interestingly, we have also found that TCL1 is overexpressed in the CD4+ and CD8+ T cells of patients with unmutated B-CLL compared to mutated CLL or healthy controls. Thus the Tcl1 transgenic murine CLL model seems suitable as a model for the immune aberrations found in human unmutated CLL.

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