scholarly journals In Vitro T Cell Activity in Two Chicken Lines Divergently Selected for Antibody Response to Sheep Erythrocytes

1994 ◽  
Vol 73 (2) ◽  
pp. 336-340 ◽  
Author(s):  
M.B. KREUKNIET ◽  
N. GIANOTTEN ◽  
M.B.G. NIEUWLAND ◽  
H.K. PARMENTIER
Blood ◽  
1988 ◽  
Vol 71 (4) ◽  
pp. 1012-1020 ◽  
Author(s):  
JS Moore ◽  
MB Prystowsky ◽  
RG Hoover ◽  
EC Besa ◽  
PC Nowell

The consistent occurrence of T cell abnormalities in patients with B cell chronic lymphocytic leukemia (B-CLL) suggest that the non- neoplastic host T cells may be involved in the pathogenesis of this B cell neoplasm. Because potential defects of immunoglobulin regulation are evident in B-CLL patients, we investigated one aspect of this by studying the T cell-mediated immunoglobulin isotype-specific immunoregulatory circuit in B-CLL. The existence of class-specific immunoglobulin regulatory mechanisms mediated by Fc receptor-bearing T cells (FcR + T) through soluble immunoglobulin binding factors (IgBFs) has been well established in many experimental systems. IgBFs can both suppress and enhance B cell activity in an isotype-specific manner. We investigated the apparently abnormal IgA regulation in a B-CLL patient (CLL249) whose B cells secrete primarily IgA in vitro. Enumeration of FcR + T cells showed a disproportionate increase in IgA FcR + T cells in the peripheral blood of this patient. Our studies showed that the neoplastic B cells were not intrinsically unresponsive to the suppressing component of IgABF produced from normal T cells, but rather the IgABF produced by the CLL249 host T cells was defective. CLL249 IgABF was unable to suppress IgA secretion by host or normal B cells and enhanced the in vitro proliferation of the host B cells. Size fractionation of both normal and CLL249 IgABF by gel-filtration high- performance liquid chromatography (HPLC) demonstrated differences in the ultraviolet-absorbing components of IgABF obtained from normal T cells v that from our patient with defective IgA regulation. Such T cell dysfunction may not be restricted to IgA regulation, since we have found similar expansion of isotype-specific FcR + T cells associated with expansion of the corresponding B cell clone in other patients with B-CLL. These data suggest that this T cell-mediated regulatory circuit could be significantly involved in the pathogenesis of B-CLL.


2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
Atar Lev ◽  
Amos J. Simon ◽  
Luba Trakhtenbrot ◽  
Itamar Goldstein ◽  
Meital Nagar ◽  
...  

Introduction. Patients with severe combined immunodeficiency (SCID) may present with residual circulating T cells. While all cells are functionally deficient, resulting in high susceptibility to infections, only some of these cells are causing autoimmune symptoms.Methods. Here we compared T-cell functions including the number of circulating CD3+T cells,in vitroresponses to mitogens, T-cell receptor (TCR) repertoire, TCR excision circles (TREC) levels, and regulatory T cells (Tregs) enumeration in several immunodeficinecy subtypes, clinically presenting with nonreactive residual cells (MHC-II deficiency) or reactive cells. The latter includes patients with autoreactive clonal expanded T cell and patients with alloreactive transplacentally maternal T cells.Results. MHC-II deficient patients had slightly reduced T-cell function, normal TRECs, TCR repertoires, and normal Tregs enumeration. In contrast, patients with reactive T cells exhibited poor T-cell differentiation and activity. While the autoreactive cells displayed significantly reduced Tregs numbers, the alloreactive transplacentally acquired maternal lymphocytes had high functional Tregs.Conclusion. SCID patients presenting with circulating T cells show different patterns of T-cell activity and regulatory T cells enumeration that dictates the immunodeficient and autoimmune manifestations. We suggest that a high-tolerance capacity of the alloreactive transplacentally acquired maternal lymphocytes represents a toleration advantage, yet still associated with severe immunodeficiency.


Surgery ◽  
2018 ◽  
Vol 163 (3) ◽  
pp. 627-632 ◽  
Author(s):  
Ramesh B. Batchu ◽  
Oksana V. Gruzdyn ◽  
Ebrahem M. Mahmud ◽  
Fatme Chukr ◽  
Rajesh Dachepalli ◽  
...  

Blood ◽  
1982 ◽  
Vol 59 (1) ◽  
pp. 198-201 ◽  
Author(s):  
JJ Hooks ◽  
BF Haynes ◽  
B Detrick-Hooks ◽  
LF Diehl ◽  
TL Gerrard ◽  
...  

Abstract We report a patient with a disease characterized by proliferation of T cells with Fc receptors for IgG (TG). However, unlike lymphoid cells from normal individuals or from patients with other lymphoid malignancies, the patient's lymphocytes spontaneously produced gamma interferon (IFN-gamma) in vitro. The peripheral lymphocytes consisted of 95% TG cells, which exhibited the morphological characteristics of T- cell chronic lymphocytic leukemia (CLL) and were normal on cytochemical and chromosome analysis. The majority of TG cells were OKT3+, OKT8+, and OKT4-, 3A1-. These cells failed to express suppressor cell activity and displayed depressed levels of natural killer activity, but mediated antibody-dependent cell-mediated cytotoxicity. The spontaneous production of IFN-gamma by human peripheral lymphoid cells as demonstrated in this study may serve as a probe for studying the relationship between IFN-gamma and the proliferation of human T-cell subsets.


1985 ◽  
Vol 162 (6) ◽  
pp. 1935-1953 ◽  
Author(s):  
Y A Mekori ◽  
G L Weitzman ◽  
S J Galli

It has been suggested that reserpine blocks expression of delayed hypersensitivity (DH) by depleting tissue mast cells of serotonin (5-HT), thereby preventing a T cell-dependent release of mast cell 5-HT necessary to localize and to amplify the DH response. However, reserpine blocks expression of DH in mast cell-deficient mice. We therefore decided to reevaluate the mechanism by which reserpine abrogates expression of cellular immunity, and investigated whether the drug might interfere with T cell activity in vitro or in vivo. At concentrations as low as 4 microM, reserpine profoundly suppressed baseline or antigen-augmented levels of [3H]thymidine incorporation by immune lymph node cells obtained from mice sensitized to the contactant oxazolone [I-LNC(Ox)]. This effect was observed both with I-LNC derived from normal mice and with I-LNC derived from congenitally mast cell-deficient W/Wv mice, cell preparations that lacked detectable mast cells, histamine, and 5-HT. Furthermore, treatment of I-LNC with reserpine (20 microM) for 1 h in vitro virtually abolished the ability of these cells to transfer CS to naive mice. This was not a cytolytic effect, as the viability of the I-LNC treated with reserpine was not affected, and washing of the reserpine-treated I-LNC before transfer fully restored their ability to orchestrate a CS response. The action of the drug was not mediated by an effect on mast cells, since the experiment could be performed using mast cell-deficient W/Wv mice as both donors and recipients of I-LNC. In addition, the effect was specific for the treated cells: mice that received reserpine-treated I-LNC(Ox) intravenously together with untreated I-LNC(DNFB) did not develop CS to Ox but responded normally to DNFB; and local intradermal injection of reserpine-treated I-LNC(Ox) which failed to transfer reactivity to Ox, did not interfere with the development of CS to DNFB at the same site. Finally, cotransfer experiments indicated that the effect of reserpine on the transfer of CS was not due to activation of suppressor cells. Our findings strongly suggest that whatever effects reserpine might have on immunologically nonspecific host cells, the drug's effects on sensitized T cells are sufficient to explain its ability to block cell-mediated immune responses in vivo.


2018 ◽  
Vol 2 (S1) ◽  
pp. 10-10
Author(s):  
Ravyn Thompson ◽  
Cara Coleman ◽  
Nathan G. Dolloff

OBJECTIVES/SPECIFIC AIMS: Immuno-oncology (IO) strategies are promising new approaches for the treatment of a variety of malignancies, including multiple myeloma (MM). Regulatory T cells (Tregs), which suppress effector T cell function, are a limitation to durable IO responses. The transcription factor FOXP3 is critical for the mature Treg phenotype. FOXP3 homodimerization is required for DNA binding and transcriptional activity, and mutations mapping to the dimerization region are associated with IPEX syndrome, resulting in dysfunctional Tregs in humans. We therefore hypothesize that inhibitors of FOXP3 dimerization will repress Treg suppression and enhance the anti-MM activity of IO. METHODS/STUDY POPULATION: To discover FOXP3 dimerization inhibitors, we are modeling FOXP3 homodimerization in vitro. Currently, we are optimizing an ALPHA screen and an ELISA-based dimerization assay using recombinant full length and truncated versions of FOXP3 to discover peptidomimetics that inhibit homodimerization. Induced Tregs expanded from human PBMCs will be treated with lead biologics and functional assays will be performed. RESULTS/ANTICIPATED RESULTS: Here we demonstrate Treg suppression of T cell proliferation and IFN-γ secretion after 5 days of co-culture under basal conditions. Additionally, we developed a MM/T cell co-culture system to measure anti-MM T cell responses and show decreased anti-MM T cell activity in the presence of Tregs. We expect to exploit the assays outlined here to demonstrate defective Treg suppression when FOXP3 dimerization is inhibited. DISCUSSION/SIGNIFICANCE OF IMPACT: These studies support drug discovery efforts that will ultimately improve IO therapies for patients with MM.


Blood ◽  
1981 ◽  
Vol 58 (3) ◽  
pp. 431-439 ◽  
Author(s):  
LG Lum ◽  
MC Seigneuret ◽  
RF Storb ◽  
RP Witherspoon ◽  
ED Thomas

Abstract Twenty-four patients with aplastic anemia or acute leukemia were treated by marrow grafts from HLA-identical donors after conditioning with high doses of cyclophosphamide and/or today body irradiation. They were studied between 4 and 63 mo (median 14.2) after transplantation. Seventeen patients had chronic graft-versus-host disease (C-GVHD) and 7 were healthy. They were studied for defects in their T- and B-cell function using and indirect hemolytic plaque assay for Ig production after 6 days of culture in the presence of pokeweek mitogen. T or B cells from the patients with or without C-GVHD were cocultured with T or B cells from their HLA-identical marrow donors or unrelated normal controls. Intrinsic B-cell defects, lack of helper T-cell activity, and suppressor T-cell activity were more frequently found in patients with C-GVHD than in healthy patients. Fifteen of the 17 patients with C-GVHD showed on or more defects in their T-and B-cell function compared to only 3 of the 7 patients without C-GVHD. None of the healthy controls, including the marrow donors, showed defects in their T- and B-cell functions. These in vitro findings may be helpful in assessing the process of immune reconstitution and the immunologic aberration found after human marrow transplantation.


Immunology ◽  
2001 ◽  
Vol 102 (4) ◽  
pp. 460-465 ◽  
Author(s):  
B. Langhans ◽  
I. Braunschweiger ◽  
S. Schweitzer ◽  
G. Jung ◽  
G. Inchauspe ◽  
...  

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