CD70 Expression on HTLV-1 Infected T Cells of Carriers and ATL Patients and Its Clinical Significance

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 1730-1730
Author(s):  
Izumi Masamoto ◽  
Sawako Horai ◽  
Tomohiro Kozako ◽  
Makoto Yoshimitsu ◽  
Junko Niimoto ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cd4 T Cells ◽  
Mononuclear Cells ◽  
Conflicts Of Interest ◽  
Surveillance Systems ◽  
Peripheral Blood Mononuclear ◽  
Tax Protein ◽  
Infected Cells

Abstract Abstract 1730 Human T-lymphotropic virus type-1(HTLV-1) is the causative agent of adult T cell leukemia/lymphoma (ATL). HTLV-1 infected T cell growth or leukemogenesis in ATL is controlled by various host immune surveillance systems. Among them, CD70 on HTLV-1 infected T cells coupled with CD27 on virus specific cytotoxic T cells has been suggested to play an important role in ATL leukemogenesis. The CD70 molecule is the only known ligand for CD27, a member of the tumor necrosis factor (TNF) receptor superfamily 7. This negative immunoregulatory pathway downregulates cytotoxic T lymphocyte activity against CD70-expressing virus infected cells. In the present study, we examined CD70 expression on primary lymphocytes of HTLV-1 carriers and ATL patients, its relationship with HTLV-1 Tax protein expression, and the effect on CTL induction. CD70 expression was higher on peripheral blood mononuclear cells (PBMCs) of HTLV-1 infected carriers compared with healthy donors (p = 0.021, n = 21, Mann-Whitney U test), and higher in ATL patients compared to carriers (p = 0.045, n = 38, Mann-Whitney U test). CD70 expression may be observed in CD4 T cells, as well as B cells, but not in CD8 T cells or monocytes. CD70 expression in CD4 T cells is related to HTLV-1 infection, because of increased detection of HTLV-1 Tax protein during over night culture of CD70-expressing cells. Experiments using an ATL cell line, in which Tax expression is inducible by doxycycline stimulation, demonstrated enhanced CD70 expression when Tax protein was induced in HTLV-1 infected cells. Anti-CD70 antibody enhanced CD107a mobilization, a marker of recent cytotoxic degranulation, in HTLV-1 Tax specific CTLs in PBMCs from asymptomatic carriers in vitro, suggesting that the CD70/CD27 pathway plays an important role in the immune response to HTLV-1 infection in carriers, as well as ATL patients. Disclosures: No relevant conflicts of interest to declare.

scholarly journals THU0046 A PIPELINE TO STUDY ANTIGEN-SPECIFIC CD4+ T CELLS IN RHEUMATOID ARTHRITIS

2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 235.1-236
Author(s):  
R. Kumar ◽  
N. Yoosuf ◽  
C. Gerstner ◽  
S. Turcinov ◽  
K. Chemin ◽  
...  
Keyword(s):  
Rheumatoid Arthritis ◽  
T Cells ◽  
T Cell ◽  
Cd4 T Cells ◽  
Mononuclear Cells ◽  
Tenascin C ◽  
Tetramer Staining ◽  
Tcr Repertoire ◽  
Citrullinated Antigen

Background:Autoimmunity to citrullinated autoantigens forms a critical component of disease pathogenesis in rheumatoid arthritis (RA). Presence of anti-citrullinated protein antibodies (ACPAs) in patients has high diagnostic value. Recently, several citrullinated antigen specific CD4+T cells have been described. However, detailed studies of their T-cell receptor usage and in-vivo profile suffer from the disadvantage that these cells are present at very low frequencies. In this context, we here present a pipeline for TCR repertoire analysis of antigen-specific CD4+T cells from RA patients, including both citrulline and influenza (control) specificities using in-vitro peptide challenge induced-cell expansion.Objectives:To enable studies of the T cell repertoire of citrullinated antigen-specific CD4+T cells in rheumatoid arthritisMethods:Peripheral blood mononuclear cells (PBMCs) (n=7) and synovial fluid mononuclear cells (SFMCs) (n=5) from HLA-DR*0401-postive RA patients were cultured in the presence of citrullinated Tenascin C peptide cocktails or influenza peptides (positive control). Citrulline reactive cells were further supplemented with recombinant human IL-15 and IL-7 on day 2. All cultures were replenished with fresh medium on day 6 and rIL-2 was added every 2 days from then. Assessment of proportion of peptide-HLA-tetramer positive cells was performed using flow cytometry whereby individual antigen-specific CD4+T cells were sorted into 96-well plates containing cell lysis buffer, followed by PCR-based alpha/beta TCR sequencing. TCR sequencing data was demultiplexed and aligned for TCR gene usage using MiXCR. Some tetramer positive cells were sorted into complete medium containing human IL-2 and PHA for expansion of antigen-specific cells. Cells were supplemented with irradiated allogenic PBMCs (30 times number of antigen specific cells). Clones of antigen specific CD4+T cells were further subjected to tetramer staining to confirm expansion of cells.Results:As evidenced by increase in frequency of tetramer positive CD4+T cells, in vitro peptide stimulation resulted in expansion of both influenza specific (Fig. 1a) and citrullinated antigen specific (Fig. 1b) CD4+T cells. Polyclonal in-vitro expansion of tenascin C tetramer positive sorted cells followed by tetramer staining further confirmed antigen specificity and enrichment for antigen specific CD4+T cells after polyclonal stimulation (Fig.1c). TCR repertoire analysis in PB and SF dataset from the first patient showed clonal expansion of influenza specific cells in both sites. Synovial fluid had more diversity of expanding clones as compared to paired PB, with few expanded clones being shared among SF and PB. We observed a more diverse TCR repertoire in citrulline specific CD4+T cells. We also observed sharing of TCR alpha chains among different citrulline specific CD4+T cell clones.Fig. 1In-vitroexpansion of antigen specific CD4+T cells:Conclusion:This method provides a highly suitable approach for investigating TCR specificities of antigen specific CD4+T cells under conditions of low cell yields. Building on this dataset will allow us to assess specific features of TCR usage of autoreactive T cells in RA.PBMCs were cultured in presence of (a) influenza (HA, MP54) and (b) citrullinated tenascin peptides. The proportion of antigen specific CD4+T cells was assessed using HLA-class II tetramer staining. We observed an increase in frequency of (a) Infleunza specific cells (red dots in upper left and lower right quadrants) and (b) citrullinated tenascin C specific cells (red dots in lower right quadrant), at day 13 post culture as compared to day 3. (c) Sorting of citrullinated tenascin specific CD4+T cells, followed by PHA expansion resulted in visible increase in proportion of citrullinated tenascin specific CD4+T cells.Disclosure of Interests:Ravi kumar: None declared, Niyaz Yoosuf: None declared, Christina Gerstner: None declared, Sara Turcinov: None declared, Karine Chemin: None declared, Vivianne Malmström Grant/research support from: VM has had research grants from Janssen Pharmaceutica

BTK Inhibitors, Irrespective of ITK Inhibition, Increase Efficacy of a CD19/CD3 Bispecific Antibody in CLL

Blood ◽  
2021 ◽  
Author(s):  
Maissa Mhibik ◽  
Erika M. Gaglione ◽  
David Eik ◽  
Ellen K Kendall ◽  
Amy Blackburn ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cytotoxic Activity ◽  
Kinase Inhibitors ◽  
Bispecific Antibody ◽  
Mononuclear Cells ◽  
Cell Function ◽  
Lymphocytic Leukemia ◽  
Peripheral Blood Mononuclear

Bruton Tyrosine Kinase inhibitors (BTKis) are a preferred treatment for patients with chronic lymphocytic leukemia (CLL). Indefinite therapy with BTKis, while effective, presents clinical challenges. Combination therapy can deepen responses, shorten treatment duration, and possibly prevent or overcome drug resistance. We previously reported on a CD19/CD3 bispecific antibody (bsAb) that recruits autologous T cell cytotoxicity against CLL cells in vitro. Compared to observations with samples from treatment-naïve patients, T cells from patients being treated with ibrutinib expanded more rapidly and exerted superior cytotoxic activity in response to the bsAb. In addition to BTK, ibrutinib also inhibits IL2 inducible T cell Kinase (ITK). In contrast, acalabrutinib, does not inhibit ITK. Whether ITK inhibition contributes to the observed immune effects is unknown. To better understand how BTKis modulate T-cell function and cytotoxic activity, we cultured peripheral blood mononuclear cells (PBMCs) from BTKi-naive, and ibrutinib- or acalabrutinib-treated CLL patients with CD19/CD3 bsAb in vitro. T-cell expansion, activation, differentiation, and cytotoxicity were increased in PBMCs from patients on treatment with either BTKi compared to that observed for BKTi-naïve patients. BTKi therapy transcriptionally downregulated immunosuppressive effectors expressed by CLL cells, including CTLA-4 and CD200. CTLA-4 blockade with ipilimumab in vitro increased the cytotoxic activity of the bsAb in BTKi-naïve but not BTKi-treated PBMCS. Taken together, BTKis enhance bsAb induced cytotoxicity by relieving T cells of immunosuppressive restraints imposed by CLL cells. The benefit of combining bsAb immunotherapy with BTKis needs to be confirmed in clinical trials.

scholarly journals Expression Cloning of an Immunodominant Family of Mycobacterium tuberculosis Antigens Using Human Cd4+ T Cells

2000 ◽  
Vol 191 (3) ◽  
pp. 551-560 ◽  
Author(s):  
Mark R. Alderson ◽  
Teresa Bement ◽  
Craig H. Day ◽  
Liqing Zhu ◽  
David Molesh ◽  
...  
Keyword(s):  
T Cells ◽  
Mycobacterium Tuberculosis ◽  
T Cell ◽  
Cd4 T Cells ◽  
Mononuclear Cells ◽  
Genomic Library ◽  
Cell Epitope ◽  
Single Amino Acid ◽  
Expression Cloning ◽  
Peripheral Blood Mononuclear

Development of a subunit vaccine for Mycobacterium tuberculosis (Mtb) is likely to be dependent on the identification of T cell antigens that induce strong proliferation and interferon γ production from healthy purified protein derivative (PPD)+ donors. We have developed a sensitive and rapid technique for screening an Mtb genomic library expressed in Escherichia coli using Mtb-specific CD4+ T cells. Using this technique, we identified a family of highly related Mtb antigens. The gene of one family member encodes a 9.9-kD antigen, termed Mtb9.9A. Recombinant Mtb9.9A protein, expressed and purified from E. coli, elicited strong T cell proliferation and IFN-γ production by peripheral blood mononuclear cells from PPD+ but not PPD− individuals. Southern blot analysis and examination of the Mtb genome sequence revealed a family of highly related genes. A T cell line from a PPD+ donor that failed to react with recombinant Mtb9.9A recognized one of the other family members, Mtb9.9C. Synthetic peptides were used to map the T cell epitope recognized by this line, and revealed a single amino acid substitution in this region when compared with Mtb9.9A. The direct identification of antigens using T cells from immune donors will undoubtedly be critical for the development of vaccines to several intracellular pathogens.

scholarly journals Donor-Derived CD4+ T Cells and Human Herpesvirus 6B Detection After Allogeneic Hematopoietic Cell Transplantation

2020 ◽  
Author(s):  
Derek J Hanson ◽  
Hu Xie ◽  
Danielle M Zerr ◽  
Wendy M Leisenring ◽  
Keith R Jerome ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cell Transplantation ◽  
Cd4 T Cells ◽  
Hematopoietic Cell Transplantation ◽  
Mononuclear Cells ◽  
Human Herpesvirus ◽  
Hematopoietic Cell ◽  
Allogeneic Hematopoietic Cell Transplantation ◽  
Peripheral Blood Mononuclear

Abstract We sought to determine whether donor-derived human herpesvirus (HHV) 6B–specific CD4+ T-cell abundance is correlated with HHV-6B detection after allogeneic hematopoietic cell transplantation. We identified 33 patients who received HLA-matched, non–T-cell–depleted, myeloablative allogeneic hematopoietic cell transplantation and underwent weekly plasma polymerase chain reaction testing for HHV-6B for 100 days thereafter. We tested donor peripheral blood mononuclear cells for HHV-6B–specific CD4+ T cells. Patients with HHV-6B detection above the median peak viral load (200 copies/mL) received approximately 10-fold fewer donor-derived total or HHV-6B–specific CD4+ T cells than those with peak HHV-6B detection at ≤200 copies/mL or with no HHV-6B detection. These data suggest the importance of donor-derived immunity for controlling HHV-6B reactivation.

scholarly journals Immunomodulatory Effects of Canine Adipose Tissue Mesenchymal Stem Cell-Derived Extracellular Vesicles on Stimulated CD4+ T Cells Isolated from Peripheral Blood Mononuclear Cells

2021 ◽  
Vol 2021 ◽  
pp. 1-20
Author(s):  
Takahiro Teshima ◽  
Yunosuke Yuchi ◽  
Ryohei Suzuki ◽  
Hirotaka Matsumoto ◽  
Hidekazu Koyama
Keyword(s):  
T Cells ◽  
Extracellular Vesicles ◽  
Cd8 T Cells ◽  
Immune Cells ◽  
Cd4 T Cells ◽  
Mononuclear Cells ◽  
Immunomodulatory Effects ◽  
Peripheral Blood Mononuclear ◽  
Blood Mononuclear Cells

Adipose tissue-derived mesenchymal stem cells (ADSCs) have anti-inflammatory and immunomodulatory characteristics. Many studies have suggested that the immunomodulation of ADSCs is largely mediated by secreted paracrine factors. Various factors are secreted from ADSCs, among which extracellular vesicles are considered to play a major role in the communication between ADSCs and target cells. Several studies have reported the function of canine ADSC-derived extracellular vesicles (cADSC-EVs), but few studies have reported the immunomodulatory effects of cADSC-EVs on immune cells. The purpose of this study was to investigate the effects of cADSC-EVs on in vitro-stimulated CD4+ T cells isolated from peripheral blood mononuclear cells (PBMCs). cADSC-EVs were isolated from cADSCs under naive conditions or primed conditions by tumor necrosis factor-α (TNFα) and interferon-γ (IFNγ). The expression levels of several microRNAs in cADSC-EVs were altered by priming with TNFα and IFNγ. Culturing PBMCs stimulated with concanavalin A in the presence of naive or primed cADSC-EVs inhibited the differentiation of PBMCs and CD4+ T cells and promoted apoptosis of PBMCs. CD4+, CD8+, and CD4+CD8+ T cells were decreased, while CD3+CD4-CD8- T cells were increased. T helper (Th) 1, Th2, Th17, and regulatory T (Treg) cells were analyzed by flow cytometry. cADSC-EVs inhibited the proliferation of Th1 and Th17 cells and enhanced Th2 and Treg cell proliferation. However, CD4+ T cells that had incorporated labeled cADSC-EVs comprised only a few percent of all cells. Therefore, these responses of stimulated CD4+ T cells may be due to not only direct effects of cADSC-EVs but also to indirect effects through interactions between cADSC-EVs and other immune cells. In conclusion, cADSC-EVs exert immunosuppressive effects on stimulated CD4+ T cells in vitro. These findings may be useful for further studies of immune diseases.

Association of changes in T regulatory cells (Treg) during nivolumab treatment with melanoma outcome.

2017 ◽  
Vol 35 (15_suppl) ◽  
pp. 3031-3031 ◽  
Author(s):  
Jeffrey S. Weber ◽  
Rupal Ramakrishnan ◽  
Andressa Laino ◽  
Anders E. Berglund ◽  
David Woods
Keyword(s):  
Gene Expression ◽  
T Cells ◽  
Cd4 T Cells ◽  
T Regulatory Cells ◽  
Mononuclear Cells ◽  
In Vitro Assays ◽  
Peripheral Blood Mononuclear ◽  
Suppressive Function ◽  
Blocking Antibodies

3031 Background: PD-1 blocking antibodies have significant efficacy in the treatment of melanoma; however, many patients fail to respond and resistance mechanisms remain unknown. We addressed the role of Tregs, an immunosuppressive T-cell population, in patient outcome after treatment with nivolumab. Methods: Peripheral blood mononuclear cells (PBMC) were obtained from patients on trials with nivolumab as adjuvant therapy for resected disease or as treatment for metastatic melanoma. To measure suppression, Tregs were flow-sorted from PBMC and evaluated in allogeneic mixed lymphocyte reactions. Tregs and conventional CD4 T-cells were evaluated for gene expression changes by RNA-sequencing. Treg percentages and phosphorylated STAT3 (pSTAT3) expression were evaluated by flow cytometry. The effects of PD-1 blockade with nivolumab were evaluated in vitro using T-cells from baseline patient PBMC samples. Results: Tregs from responding patients or adjuvant patients without evidence of disease (NED) had reduced suppressive function post-nivolumab (p < 0.05), but no changes were observed in relapsing/non-responding patients; their Tregs were more suppressive than NED/responding Tregs (p < 0.001). NED Tregs had unique gene expression changes and associated pathways post-nivolumab compared to relapsing patient Tregs and conventional CD4 T-cells, including up-regulation of proliferation pathways (q < 8e-19) and downregulation of oxidative phosphorylation (q < 7e-5). NED Tregs had upregulation of pSTAT3 expression post-nivolumab (p < 0.05), which was not observed in relapsing patients. Evaluation of Tregs from patients with active disease also showed upregulation of pSTAT3 in responders (p < 0.05) but not non-responders. The relative increase in Treg pSTAT3 was associated with increased overall survival (R2= 0.49, p < 0.05). In vitro assays using PD-1 blocking antibodies recapitulated the increase in pSTAT3 (p < 0.05) and Treg percentages (p < 0.001), which were diminished with the addition of a STAT3 inhibitor (p < 0.01). Conclusions: These results demonstrate previously unknown roles of decreased Treg suppressive function and induction of STAT3 as biomarkers of patient’s outcome to nivolumab therapy.

Naïve T Cell-Derived CTL Recognize Atypical Epitopes of CMVpp65 with Higher Avidity Than CMV-Seropositive Donor-Derived CTL – a Basis for Treatment of Post-Transplant Viral Infection by Adoptive Transfer of T Cells From Virus-naïve Donors

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 3002-3002
Author(s):  
Patrick J Hanley ◽  
J. Joseph Melenhorst ◽  
Phillip Scheinberg ◽  
Gail J Demmler-Harrison ◽  
Daniele Lilleri ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Adoptive Transfer ◽  
Memory T Cells ◽  
Conflicts Of Interest ◽  
Target Cells ◽  
Naive T Cells ◽  
Naïve T Cells ◽  
Infected Cells

Abstract Abstract 3002 Adoptive transfer of CMV-specific T cells derived from adult CMV-seropositive (CMVpos) donors can effectively restore antiviral immunity after stem cell transplantation. However due to the absence of CMV antigen-specific memory T cells in cord blood (CB) and adult CMV-seronegative (CMVneg) donors, different culture systems are required to generate virus-specific T cells for adoptive transfer. With a novel protocol we have generated CMVpp65-specific T cells from CB and found that 15/15 CB T cell lines recognized atypical epitopes of pp65. We then explored the generation of CMV-specific CTL from CMVneg donors using a GMP-compliant methodology and studied the epitopes recognized. CD45RA+ naive T cells were selected from the peripheral blood of CMVneg donors and stimulated with pp65-Pepmix-pulsed dendritic cells with supplemented with IL-7, IL-12, and IL-15. For subsequent stimulations T cells were stimulated with pp65-Pepmix-pulsed EBV-LCL and IL-15 or IL-2. CMVpp65-specific T cells (CMV-CTL) expanded from 8 of 11 CMVneg donors were primarily CD8+ T cells (mean 71%). Naïve donor CMV-CTL secreted IFN- γ in response to pp65 peptides (mean 224; range: 38–611 SFC/1×105 cells) compared to irrelevant peptides (mean 12;Range 3–37) as measured in Elispot assays and lysed pp65-pulsed target cells (mean :48; range :15–70%) but not negative controls (mean 22; range 4–40%). These CMV-CTL derived from naive (but not memory) T cells recognized only novel and atypical pp65 epitopes (such as the HLA-A2-restricted epitopes LQTGIHVRV and MLNIPSINV) but not the typical HLA-A2-restricted epitope NLVPMVATV as confirmed by ELISPOT and multimer analysis. These results are similar to CB-derived CTL. Analysis of the avidity of naïve donor CTL specific for the atypical CMV epitopes revealed that the 1/2 maximum effective concentration was similar (mean: 600 pM) to CMVpos CTL recognizing typical epitopes (mean: 300 pM), and more avid than CMVpos CTL recognizing atypical epitopes (mean: 4 nM), highlighting the difference between naïve-derived and memory-derived CTL. TCR sequencing performed on T cells specific for typical (CMVpos) and atypical (CMVpos, CMVneg, and CB) epitopes revealed that CMVpos donor CMV-CTL recognizing typical epitopes were markedly more oligoclonal than CTL recognizing the atypical epitopes derived from CB, CMVpos, or CMVneg donors. To address the concern that atypical epitopes might not be naturally presented by CMV-infected cells and therefore not recognized by in vitro generated CTL, we tested whether CMV CTL (from CB, CMVpos, CMVneg) generated using CMV AD169-infected fibroblasts or CMV VR1814-infected DCs would recognize the same epitopes. As before, CMVpos CMV CTL recognized typical epitopes of pp65 while CB and CMVneg CMV CTL recognized only atypical epitopes, suggesting that the epitopes are naturally processed and presented by APCs, and that the atypical epitopes observed are not an artifact of using exogenous antigens like the pp65 Pepmix. Thus, despite their unusual repertoire, T cells derived from CB or CMVneg donors are likely to control CMV infection. These results reveal major differences in the naïve and memory CMV specific T cell repertoire that merits further exploration. Nevertheless, we demonstrated that atypical epitopes are naturally presented by CMV infected cells and we are now evaluating the clinical efficacy of these CTL in recipients of CBT. These studies should determine if naive T cells primed in vitro are able to persist and establish memory and virus protection in vivo. Disclosures: No relevant conflicts of interest to declare.

scholarly journals VIP contribution to the decidualization program: regulatory T cell recruitment

2014 ◽  
Vol 221 (1) ◽  
pp. 121-131 ◽  
Author(s):  
Esteban Grasso ◽  
Daniel Paparini ◽  
Mariana Agüero ◽  
Gil Mor ◽  
Claudia Pérez Leirós ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Mononuclear Cells ◽  
Active Role ◽  
Dependent Manner ◽  
Endometrial Stromal Cells ◽  
Peripheral Blood Mononuclear ◽  
Cell Recruitment ◽  
Stromal Cell Line

During early pregnancy, the human uterus undergoes profound tissue remodeling characterized by leukocyte invasion and production of proinflammatory cytokines, followed by tissue repair and tolerance maintenance induction. Vasoactive intestinal peptide (VIP) is produced by trophoblast cells and modulates the maternal immune response toward a tolerogenic profile. Here, we evaluated the contribution of the VIP/VPAC to endometrial renewal, inducing decidualization and the recruitment of induced regulatory T cells (iTregs) that accompany the implantation period. For that purpose, we used an in vitro model of decidualization with a human endometrial stromal cell line (HESC) stimulated with progesterone (P4) and lipopolysaccharide (LPS) simulating the inflammatory response during implantation and human iTregs (CD4+CD25+FOXP3+) differentiated from naïve T cells obtained from peripheral blood mononuclear cells of fertile women. We observed that VIP and its receptor VPAC1 are constitutively expressed in HESCs and that P4 increased VIP expression. Moreover, in HESC VIP induced expression of RANTES (CCL5), one of the main chemokines involved in T cell recruitment, and this effect is enhanced by the presence of P4 and LPS. Finally, assays of the migration of iTregs toward conditioned media from HESCs revealed that endogenous VIP production induced by P4 and LPS and RANTES production were involved, as anti-RANTES neutralizing Ab or VIP antagonist prevented their migration. We conclude that VIP may have an active role in the decidualization process, thus contributing to recruitment of iTregs toward endometrial stromal cells by increasing RANTES expression in a P4-dependent manner.

scholarly journals Functional biomarker signatures of circulating T-cells and its association with distinct clinical status of leprosy patients and their respective household contacts

2020 ◽  
Author(s):  
Pedro Henrique Ferreira Marçal ◽  
Rafael Silva Gama ◽  
Lorena Bruna de Oliveira Pereira ◽  
Olindo Assis Martins Filho ◽  
Roberta Olmo Pinheiro ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Mononuclear Cells ◽  
Clinical Status ◽  
T Cell Subsets ◽  
Diagnostic Tools ◽  
Peripheral Blood Mononuclear ◽  
Household Contacts ◽  
Leprosy Patients

Abstract Background: Leprosy is a chronic infectious disease classified into two subgroups for therapeutic purposes: paucibacillary (PB) and multibacillary (MB), closely related to the host immune responses. In this context it is noteworthy looking for immunological biomarkers applicable as complementary diagnostic tools as well as a laboratorial strategy to detect subclinical leprosy in household contacts. Methods: The main goal of the present study was to characterize the global cytokine signatures of CD4+ and CD8+ T-cells from leprosy patients with distinct clinical forms and their respective household contacts (HHC) upon in vitro antigen-specific stimuli. Short-term culture of peripheral blood mononuclear cells was done. After incubation, cells were harvested and prepared for surface and intracytoplasmic cytokine staining Results: The cytokine signature analysis demonstrated that leprosy patients presented a polyfunctional profile of T-cells subsets, with increased frequency of IFN-g+ T-cell subsets along with IL-10+ and IL-4+ from CD4+ T-cells. Moreover, L(PB) displayed a polyfunctional profile characterized by enhanced percentage of IFN-g+, IL-10+ and IL-4+ produced by most T-cell subsets, as compared to L(MB) that presented a more restricted cytokine functional profile mediated by IL-10+ and IL-4+ T-cells with minor contribution of IFN-g produced by CD4+ T-cells. Noteworthy was that HHC(MB) exhibited enhanced frequency of IFN-g+ T-cells, contrasting with HHC(PB) that presented a cytokine profile limited to IL-10 and IL-4. Conclusions: Together, our findings provide additional immunological features associated with leprosy and household contacts. These data provide evidence that biomarkers of immune response can be useful complementary diagnostic/prognostic tools as well as insights that household contacts may present subclinical infection.

scholarly journals Selection and T-cell antigenicity of synthetic long peptides derived from SARS-CoV-2

2022 ◽  
Vol 103 (1) ◽  
Author(s):  
Katarzyna Piadel ◽  
Amin Haybatollahi ◽  
Angus George Dalgleish ◽  
Peter Lawrence Smith
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Cell Activation ◽  
Cell Activation ◽  
Mononuclear Cells ◽  
T Cell Responses ◽  
Hla Class I ◽  
Peripheral Blood Mononuclear ◽  
Cell Responses

The pandemic caused by SARS-CoV-2 has led to the successful development of effective vaccines however the prospect of variants of SARS-CoV-2 and future coronavirus outbreaks necessitates the investigation of other vaccine strategies capable of broadening vaccine mediated T-cell responses and potentially providing cross-immunity. In this study the SARS-CoV-2 proteome was assessed for clusters of immunogenic epitopes restricted to diverse human leucocyte antigen. These regions were then assessed for their conservation amongst other coronaviruses representative of different alpha and beta coronavirus genera. Sixteen highly conserved peptides containing numerous HLA class I and II restricted epitopes were synthesized from these regions and assessed in vitro for their antigenicity against T-cells from individuals with previous SARS-CoV-2 infection. Monocyte derived dendritic cells were generated from these peripheral blood mononuclear cells (PBMC), loaded with SARS-CoV-2 peptides, and used to induce autologous CD4+ and CD8+ T cell activation. The SARS-CoV-2 peptides demonstrated antigenicity against the T-cells from individuals with previous SARS-CoV-2 infection indicating that this approach holds promise as a method to activate anti-SAR-CoV-2 T-cell responses from conserved regions of the virus which are not included in vaccines utilising the Spike protein.

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