Bexarotene-Induced T-Cell Immunomodulation and Response in CTCL.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 744-744 ◽  
Author(s):  
Pierluigi Porcu ◽  
Robert Baiocchi ◽  
Maureen Buckner ◽  
John C. Byrd ◽  
Cynthia M. Magro

Abstract Cutaneous T-cell lymphoma (CTCL) is a group of chronic lymphoproliferative disorders mostly of skin-homing CD4+ T-cells associated with profound suppression of cell-mediated immunity and loss of T-cell reportoire. The immunological effects of current CTCL therapies and their impact on response have not been studied in large samples of patients. Bexarotene is a synthetic retinoic X receptor (RXR) agonist that induces apoptosis in malignant T-cells and has significant clinical activity in CTCL. Bexarotene also exerts multiple effects on normal T-cells. We investigated the in-vivo immunomodulatory effects of bexarotene in patients with CTCL and correlated them with response. 37 patients (pts) with stage IB-III CTCL (33 Mycosis Fungoides, 1 ALCL, 3 pleomorphic small cell) received oral bexarotene (150–300 mg/m2/day) for a median duration of 13 months (range 4–18). Peripheral blood (PB) T-cell subpopulations were measured by multicolor flow cytometry at baseline and during therapy. Circulating CTCL cells were defined as CD4+ CD7− T-cells. 32/37 patients had an elevated PB CD4/CD8 ratio at diagnosis, regardless of the presence of circulating CTCL cells (3/37 pts) and 33/37 pts had a low absolute CD8+ T-cell count (median 98 cells/mm3, normal 150–1000/mm3). After a median time of 6.5 weeks on bexarotene (range 3.5–12) the CD8+ T-cell count had returned within normal range in 26/33 pts and the CD4/CD8 ratio had decreased in 27/32 pts. Responses (defined as Pysician Global Assessment [PGA] of clinical condition) were observed in 24/37 pts (64.8%). Responders had significantly higher peak CD8+ T-cell counts compared to non-responders (median 975/mm3 vs 221/mm3, P=0.002) and lower CD4/CD8 ratios (median 0.8 vs 2.4, P=0.005). At this time 21 pts have relapsed, with median duration of response 9.5 months. A ≥50% decrease in the PB CD8+ T-cell count preceded cutaneous relapse in 17/21 pts (81%) by a median time of 4.5 weeks (range 3–6.5 weeks). Functional analysis (mitogenic response, cytokine secretion, antigenic repertoire) of PB T-cell subpopulations from these pts at baseline and during therapy with bexarotene is in progress. Bexarotene appears to have a profound in vivo T-cell immunomodulatory effect in CTCL pts. The importance of these immune effects for clinical response vis-a-vis direct induction of apoptosis in CTCL needs to be further studied. If these results are confirmed in larger samples, monitoring of PB T-cell subpopulations may provide clinically valuable information in predicting response and relapse.

1996 ◽  
Vol 70 (3) ◽  
pp. 211-214 ◽  
Author(s):  
J.D. Lee ◽  
J.J. Wang ◽  
J.H. Chang ◽  
L.Y. Chung ◽  
E.R. Chen ◽  
...  

AbstractWhen C57BL/6 mice were infected with Angiostrongylus cantonensis, the percentage of T helper (CD4+) cells and T supressor (CD8+) cells in peripheral blood increased weekly until the third and seventh week respectively, and then gradually decreased. C57BL/6 mice were depleted of CD4+ and CD8+ T cells by in vivo injection of anti-CD4 and anti-CD8 monoclonal antibodies, respectively, and then infected with A. cantonensis. There were significantly more and less worms recovered in the mice depleted of CD4+ and CD8+ T cells respectively than in undepleted mice. Discrete subpopulations of T cells from mice exposed to A. cantonensis for 3 weeks or 7 weeks were adoptively transferred to syngeneic recipients which were then given a challenge infection. Protection was mediated by a CD4+ T cell population present in mice after 3 weeks of infection but was not demonstrable with cells taken 7 weeks after infection. When CD4+ T cells obtained from 3-week infected mice were mixed with 5% CD8+ T cells obtained from mice infected for 7 weeks, no significant transfer of resistance was observed. Thus, immune responses to A. cantonensis in mice were regulated by discrete subpopulations of T lymphocytes.


Neonatology ◽  
1996 ◽  
Vol 69 (2) ◽  
pp. 128-132 ◽  
Author(s):  
Sadhana Chheda ◽  
Kimberly H. Palkowetz ◽  
David K. Rassin ◽  
Armond S. Goldman

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Fan Jin ◽  
Jing Xie ◽  
Huan-ling Wang

Abstract Objectives We analysed the peripheral blood lymphocyte subsets of human immunodeficiency virus (HIV)-negative patients infected with pneumocystis pneumonia (PCP) to determine the relationships between the levels of different types of lymphocytes and the prognosis of patients. Methods We retrospectively reviewed HIV-negative patients with PCP diagnosed in our department. All the eligible patients underwent lymphocyte subset analysis on admission. Results A total of 88 HIV-negative PCP patients were enrolled in the study. In univariate analyses, low CD4+ T cell count, low CD8+ T cell count, and low natural killer cell (NK cell) count were associated with higher in-hospital mortality. CD8+ T cell count ≤300/μL was found to be an independent risk factor for poor prognosis in multivariate logistical regression analysis (p = 0.015, OR = 11.526, 95% CI = 1.597–83.158). Although low CD4+ T cell and NK cell counts were not independent risk factors, the mortality rates of PCP patients decreased as the CD4+ T cell and NK cell counts increased. Conclusion The immune process of Pneumocystis jirovecii infection is complex but important. We propose that lymphocyte subsets could give clinicians a better understanding of patient immune status, helping with the early identification of potentially lethal infections and treatment decision making, such as adjusting the immunosuppressive regimen and choosing an appropriate patient monitoring level.


2020 ◽  
Vol 22 (1) ◽  
pp. 274
Author(s):  
Claudia Curci ◽  
Angela Picerno ◽  
Nada Chaoul ◽  
Alessandra Stasi ◽  
Giuseppe De Palma ◽  
...  

Adult Renal Stem/Progenitor Cells (ARPCs) have been recently identified in the human kidney and several studies show their active role in kidney repair processes during acute or chronic injury. However, little is known about their immunomodulatory properties and their capacity to regulate specific T cell subpopulations. We co-cultured ARPCs activated by triggering Toll-Like Receptor 2 (TLR2) with human peripheral blood mononuclear cells for 5 days and 15 days and studied their immunomodulatory capacity on T cell subpopulations. We found that activated-ARPCs were able to decrease T cell proliferation but did not affect CD8+ and CD4+ T cells. Instead, Tregs and CD3+ CD4- CD8- double-negative (DN) T cells decreased after 5 days and increased after 15 days of co-culture. In addition, we found that PAI1, MCP1, GM-CSF, and CXCL1 were significantly expressed by TLR2-activated ARPCs alone and were up-regulated in T cells co-cultured with activated ARPCs. The exogenous cocktail of cytokines was able to reproduce the immunomodulatory effects of the co-culture with activated ARPCs. These data showed that ARPCs can regulate immune response by inducing Tregs and DN T cells cell modulation, which are involved in the balance between immune tolerance and autoimmunity.


2000 ◽  
Vol 191 (3) ◽  
pp. 541-550 ◽  
Author(s):  
Zhengbin Lu ◽  
Lingxian Yuan ◽  
Xianzheng Zhou ◽  
Eduardo Sotomayor ◽  
Hyam I. Levitsky ◽  
...  

In many cases, induction of CD8+ CTL responses requires CD4+ T cell help. Recently, it has been shown that a dominant pathway of CD4+ help is via antigen-presenting cell (APC) activation through engagement of CD40 by CD40 ligand on CD4+ T cells. To further study this three cell interaction, we established an in vitro system using dendritic cells (DCs) as APCs and influenza hemagglutinin (HA) class I and II peptide–specific T cell antigen receptor transgenic T cells as cytotoxic T lymphocyte precursors and CD4+ T helper cells, respectively. We found that CD4+ T cells can provide potent help for DCs to activate CD8+ T cells when antigen is provided in the form of either cell lysate, recombinant protein, or synthetic peptides. Surprisingly, this help is completely independent of CD40. Moreover, CD40-independent CD4+ help can be documented in vivo. Finally, we show that CD40-independent T cell help is delivered through both sensitization of DCs and direct CD4+–CD8+ T cell communication via lymphokines. Therefore, we conclude that CD4+ help comprises at least three components: CD40-dependent DC sensitization, CD40-independent DC sensitization, and direct lymphokine-dependent CD4+–CD8+ T cell communication.


2008 ◽  
Vol 205 (13) ◽  
pp. 2965-2973 ◽  
Author(s):  
Susan Gilfillan ◽  
Christopher J. Chan ◽  
Marina Cella ◽  
Nicole M. Haynes ◽  
Aaron S. Rapaport ◽  
...  

Natural killer (NK) cells and CD8 T cells require adhesion molecules for migration, activation, expansion, differentiation, and effector functions. DNAX accessory molecule 1 (DNAM-1), an adhesion molecule belonging to the immunoglobulin superfamily, promotes many of these functions in vitro. However, because NK cells and CD8 T cells express multiple adhesion molecules, it is unclear whether DNAM-1 has a unique function or is effectively redundant in vivo. To address this question, we generated mice lacking DNAM-1 and evaluated DNAM-1–deficient CD8 T cell and NK cell function in vitro and in vivo. Our results demonstrate that CD8 T cells require DNAM-1 for co-stimulation when recognizing antigen presented by nonprofessional antigen-presenting cells; in contrast, DNAM-1 is dispensable when dendritic cells present the antigen. Similarly, NK cells require DNAM-1 for the elimination of tumor cells that are comparatively resistant to NK cell–mediated cytotoxicity caused by the paucity of other NK cell–activating ligands. We conclude that DNAM-1 serves to extend the range of target cells that can activate CD8 T cell and NK cells and, hence, may be essential for immunosurveillance against tumors and/or viruses that evade recognition by other activating or accessory molecules.


Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 21-21
Author(s):  
Gisele Olinto Libanio Rodrigues ◽  
Julie Hixon ◽  
Hila Winer ◽  
Erica Matich ◽  
Caroline Andrews ◽  
...  

Mutations of the IL-7Rα chain occur in approximately 10% of pediatric T-cell acute lymphoblastic leukemia cases. While we have shown that mutant IL7Ra is sufficient to transform an immortalized thymocyte cell line, mutation of IL7Ra alone was insufficient to cause transformation of primary T cells, suggesting that additional genetic lesions may be present contributing to initiate leukemia. Studies addressing the combinations of mutant IL7Ra plus TLX3 overexpression indicates in vitro growth advantage, suggesting this gene as potential collaborative candidate. Furthermore, patients with mutated IL7R were more likely to have TLX3 or HOXA subgroup leukemia. We sought to determine whether combination of mutant hIL7Ra plus TLX3 overexpression is sufficient to generate T-cell leukemia in vivo. Double negative thymocytes were isolated from C57BL/6J mice and transduced with retroviral vectors containing mutant hIL7R plus hTLX3, or the genes alone. The combination mutant hIL7R wild type and hTLX3 was also tested. Transduced thymocytes were cultured on the OP9-DL4 bone marrow stromal cell line for 5-13 days and accessed for expression of transduced constructs and then injected into sublethally irradiated Rag-/- mice. Mice were euthanized at onset of clinical signs, and cells were immunophenotyped by flow cytometry. Thymocytes transduced with muthIL-7R-hTLX3 transformed to cytokine-independent growth and expanded over 30 days in the absence of all cytokines. Mice injected with muthIL7R-hTLX3 cells, but not the controls (wthIL7R-hTLX3or mutIL7R alone) developed leukemia approximately 3 weeks post injection, characterized by GFP expressing T-cells in blood, spleen, liver, lymph nodes and bone marrow. Furthermore, leukemic mice had increased white blood cell counts and presented with splenomegaly. Phenotypic analysis revealed a higher CD4-CD8- T cell population in the blood, bone marrow, liver and spleen compared in the mutant hIL7R + hTLX3 mice compared with mice injected with mutant IL7R alone indicating that the resulting leukemia from the combination mutant hIL7R plus hTLX3 shows early arrest in T-cell development. Taken together, these data show that oncogenic IL7R activation is sufficient for cooperation with hTLX3 in ex vivo thymocyte cell transformation, and that cells expressing the combination muthIL7R-hTLX3 is sufficient to trigger T-cell leukemia in vivo. Figure Disclosures No relevant conflicts of interest to declare.


1979 ◽  
Vol 149 (1) ◽  
pp. 228-233 ◽  
Author(s):  
A B Reske-Kunz ◽  
M P Scheid ◽  
E A Boyse

Mice of the HRS strain, which carry the mutant gene hr, were examined for abnormalities in representation of the three T-cell sets Ly1, Ly23, and Ly123 in the spleen. The salient feature of hr/hr mice, which are immunologically deficient, in comparison with +/hr segregants, was a gross disproportion in numbers of cells belonging to the Ly1 and Ly123 sets, at the age of 3--3.5 mo. At this age, Ly123 cells of hr/hr spleen outnumbered Ly1 cells by 2:1, whereas in +/hr spleens Ly123 cells were outnumbered by approximately 1:2. Cells from pooled lymph nodes of hr/hr mice did not show a correspondingly gross disporprotion of Ly1 and Ly123 cells. Total counts of splenic T cells, and of B cells, were not significantly different in hr/hr and +/hr mice.


Author(s):  
Mandisa Skhosana ◽  
Shabashini Reddy ◽  
Tarylee Reddy ◽  
Siphelele Ntoyanto ◽  
Elizabeth Spooner ◽  
...  

Introduction: Limited information is available on the usefulness of the PIMATM analyser in predicting antiretroviral treatment eligibility and outcome in a primary healthcare clinic setting in disadvantaged communities in KwaZulu-Natal, South Africa.Materials and methods: The study was conducted under the eThekwini Health Unit, Durban, KwaZulu-Natal. Comparison of the enumeration of CD4+ T-cells in 268 patients using the PIMATM analyser and the predicate National Health Laboratory Services (NHLS) was undertaken during January to July 2013. Bland-Altman analysis to calculate bias and limits of agreement, precision and levels of clinical misclassification at various CD4+ T-cell count thresholds was performed.Results: There was high precision of the PIMATM control bead cartridges with low and normal CD4+ T-cell counts using three different PIMATM analysers (%CV < 5). Under World Health Organization (WHO) guidelines (≤ 500 cells/mm3), the sensitivity of the PIMATM analyser was 94%, specificity 78% and positive predictive value (PPV) 95%. There were 24 (9%) misclassifications, of which 13 were false-negative in whom the mean bias was 149 CD4+ T-cells/mm3. Most (87%) patients returned for their CD4 test result but only 67% (110/164) of those eligible (≤ 350 cells/mm3) were initiated on antiretroviral therapy (ART) with a time to treatment of 49 days (interquartile range [IQR], 42–64 days).Conclusion: There was adequate agreement between PIMATM analyser and predicate NHLS CD4+ T-cell count enumeration (≤ 500 cells/mm3) in adult HIV-positive individuals. The high PPV, sensitivity and acceptable specificity of the PIMATM analyser technology lend it as a reliable tool in predicting eligibility and rapid linkage to care in ART programmes.Keywords: HIV; Point of Care; PIMATM CD4+ T cell counts; antiretroviral therapy; prediction/eligibility; South Africa


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