scholarly journals Changes in T-Cell and Monocyte PhenotypesIn VitrobySchistosoma mansoniAntigens in Cutaneous Leishmaniasis Patients

2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
Aline Michelle Barbosa Bafica ◽  
Luciana Santos Cardoso ◽  
Sérgio Costa Oliveira ◽  
Alex Loukas ◽  
Alfredo Góes ◽  
...  

High levels of proinflammatory cytokines such as IFN-γand TNF are associated with tissue lesions in cutaneous leishmaniasis (CL). We previously demonstrated thatSchistosoma mansoniantigens downmodulate thein vitrocytokine response in CL. In the current study we evaluated whetherS. mansoniantigens alter monocyte and T-lymphocyte phenotypes in leishmaniasis. Peripheral blood mononuclear cells of CL patients were cultured withL. braziliensisantigen in the presence or absence of theS. mansoniantigens rSm29, rSmTSP-2- and PIII. Cells were stained with fluorochrome conjugated antibodies and analyzed by flow cytometry. The addition of rSm29 to the cultures decreased the expression of HLA-DR in nonclassical (CD14+CD16++) monocytes, while the addition of PIII diminished the expression of this molecule in classical (CD14++CD16-) and intermediate (CD14++CD16+) monocytes. The addition of PIII and rSmTSP-2 resulted in downmodulation of CD80 expression in nonclassical and CD86 expression in intermediate monocytes, respectively. These two antigens increased the expression of CTLA-4 in CD4+T cells and they also expanded the frequency of CD4+CD25highFoxp3+T cells. Taken together, we show thatS. mansoniantigens, mainly rSmTSP-2 and PIII, are able to decrease the activation status of monocytes and also to upregulate the expression of modulatory molecules in T lymphocytes.

Blood ◽  
1996 ◽  
Vol 88 (6) ◽  
pp. 2118-2124 ◽  
Author(s):  
G Pawelec ◽  
H Max ◽  
T Halder ◽  
O Bruserud ◽  
A Merl ◽  
...  

Chronic myelogenous leukemia (CML) is characterized by the t(9;22) translocation that results in chimeric genes encoding bcr/abl fusion proteins. Junction-spanning sequences represent unique tumor-specific moieties that might be exploited therapeutically. We investigate here the binding of synthetic bcr/abl peptides to various HLA-DR alleles and their recognition by T cells from normal donors and CML patients. A 23- mer b3/a2 peptide bound very strongly to isolated HLA-DRB1*1101 (Dw5) and relatively strongly to DRB1*0301 (Dw3) and DRB1*0402 (Dw10) molecules, as estimated using a competition assay. It failed to bind to several other DR alleles, including three different DR4 alleles. In contrast, a 23-mer b2/a2 peptide bound only to the DRB1*0301 (Dw3) allele. Peripheral blood mononuclear cells from normal donors were sensitized in vitro against the b3/a2 peptide. After four repetitive stimulations, T cells responding to the peptide were found at low frequency in 5 of the 11 donors tested. Three of the five were HLA- DR11+, and all three of the DR11+ donors tested were found to respond. T cells recognizing bcr/abl peptides were not identified in any of the CML patients studied, regardless of HLA type. Finally, even peptide- reactive T-cell lines from normal donors were not stimulated by native CML cells in the absence of exogenous peptide. These results show the presence of low-frequency major histocompatability complex class II- restricted bcr/abl-responses in the normal T-cell repertoire of donors with certain HLA types, but suggest that unmodified tumor cells cannot be recognized by such peptide-sensitized T cells.


2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Diego Mota Lopes ◽  
Jamille Souza Fernandes ◽  
Thiago Marconi de Souza Cardoso ◽  
Aline Michele Barbosa Bafica ◽  
Sérgio Costa Oliveira ◽  
...  

The inflammatory response in cutaneous leishmaniasis (CL), although responsible for controlling the infection, is associated with the pathogenesis of disease. Conversely, the immune response induced byS. mansoniantigens is able to prevent immune-mediated diseases. The aim of this study was to evaluate the potential of theS. mansoniSm29 antigen to change the profile of monocyte-derived dendritic cells (MoDCs) from subjects with cutaneous leishmaniasis (CL)in vitro. Monocytes derived from the peripheral blood mononuclear cells of twelve patients were cultured with GM-CSF and IL-4 for differentiation into dendritic cells and then stimulated with solubleLeishmaniaantigen (SLA) in the presence or absence of Sm29 antigen. The expression of surface molecules associated with maturation and activation (HLA-DR, CD40, CD83, CD80, and CD86), inflammation (IL-12, TNF), and downregulation (IL-10, IL-10R) was evaluated using flow cytometry. We observed that the frequencies of HLA-DR, CD83, CD80, and CD86 as well as of IL-10 and IL-10R on MoDCs were higher in cultures stimulated with Sm29, compared to the unstimulated cell cultures. Our results indicate that the Sm29 antigen is able to activate regulatory MoDCs in patients with cutaneous leishmaniasis. It might be useful to control the inflammatory process associated with this disease.


Blood ◽  
1984 ◽  
Vol 64 (3) ◽  
pp. 707-714 ◽  
Author(s):  
RL Edwards ◽  
D Perla

Abstract Human monocytes generate the procoagulant tissue factor (MTF) following exposure to a variety of immune stimuli in vitro. The generation of MTF is modified by T cells, lymphokines, and immunoregulatory lipoproteins, and recent studies have shown that MTF can be activated in an immune- specific manner following exposure to antigen. We have examined the role of serum factors in the regulation of MTF generation. Low concentrations (less than 1%) of heat-inactivated normal human serum greatly enhanced MTF generation in cultures of normal peripheral blood mononuclear cells. The stimulatory effect was observed in cultures of both unstimulated cells and cells exposed to bacterial lipopolysaccharide. Stimulation was not observed at high serum concentrations (greater than 10%) and could not be explained by endotoxin contamination or activation of the assay system. Stimulatory activity was present in plasma and BaSO4-adsorbed plasma as well as autologous and allogeneic serum, was not abolished by removal of serum lipoproteins, and did not require the presence of T cells for its expression. Sera from 28 different normal volunteers were screened for stimulatory activity and demonstrated a wide variation in potency. These results suggest that a potent factor is present in sera that enhances the expression of MTF activity in vitro. This factor is distinct from previously described lipoprotein regulators and may play a role in the initiation of coagulation in both normal hemostasis and pathologic states.


2008 ◽  
Vol 76 (10) ◽  
pp. 4538-4545 ◽  
Author(s):  
William W. Kwok ◽  
Junbao Yang ◽  
Eddie James ◽  
John Bui ◽  
Laurie Huston ◽  
...  

ABSTRACT Cellular immune responses against protective antigen (PA) of Bacillus anthracis in subjects that received the anthrax vaccine adsorbed (AVA) vaccine were examined. Multiple CD4+ T-cell epitopes within PA were identified by using tetramer-guided epitope mapping. PA-reactive CD4+ T cells with a CD45RA− phenotype were also detected by direct ex vivo staining of peripheral blood mononuclear cells (PBMC) with PA-specific tetramers. Surprisingly, PA-specific T cells were also detected in PBMC of nonvaccinees after a single cycle of in vitro PA stimulation. However, PA-reactive CD4+ T cells in nonvaccinees occurred at lower frequencies than those in vaccinees. The majority of PA-reactive T cells from nonvaccinees were CD45RA+ and exhibited a Th0/Th1 cytokine profile. In contrast, phenotyping and cytokine profile analyses of PA-reactive CD4+ T cells from vaccinees indicated that vaccination leads to commitment of PA-reactive T cells to a Th2 lineage, including generation of PA-specific, pre-Th2 central memory T cells. These results demonstrate that the current AVA vaccine is effective in skewing the development of PA CD4+ T cells to the Th2 lineage. The data also demonstrated the feasibility of using class II tetramers to analyze CD4+ cell responses and lineage development after vaccination.


Blood ◽  
1991 ◽  
Vol 78 (7) ◽  
pp. 1770-1780 ◽  
Author(s):  
M Massaia ◽  
A Bianchi ◽  
C Attisano ◽  
S Peola ◽  
V Redoglia ◽  
...  

Abstract Cellular immunity was investigated in 43 patients with multiple myeloma (MM) by assessing 3HTdR uptake induced by monocyte-dependent [CD3 monoclonal antibodies (MoAbs), phytohemagglutinin (PHA)] and monocyte- independent (CD2 MoAbs, ionomycin + phorbolester) stimulations. The former were evaluated in peripheral blood mononuclear cells (PBMNC) and purified T cells; the latter were evaluated in purified T-cell preparations only. MM showed significantly lower PBMNC responses to PHA (P less than .001), soluble OKT3 (CD3) (P = .01), and immobilized OKT3 MoAbs (P = .01). On purification of T cells, MM responses were still defective to soluble T11(2) + T11(3) (CD2) MoAbs (P = .004), phorbol myristate acetate (PMA) plus ionomycin (P less than .001), but significantly higher to plastic-immobilized OKT3 (P = .004). In some MM, 3HTdR uptake, interleukin-2 (IL-2) receptor (CD25) expression, and IL-2 production were as high on stimulation with plastic-immobilized OKT3 as that observed in normal subjects under optimal conditions (ie, plastic-immobilized OKT3 plus accessory signals). CD3 hyperreactivity correlated with the number of CD8+ HLA-DR+ cells in MM T-cell preparations. MM patients with more than 10% CD8+ HLA-DR+ cells had significantly higher responses to immobilized OKT3 (P less than .001), but lower responses to T11(2) plus T11(3) (P = .01), and PMA plus ionomycin (P = .03) than patients with less than 10% CD8+ HLA-DR+ cells. Phenotyping of CD45RA (naive) and CD45R0 (memory) expressions in resting MM T cells showed a lower ratio of CD45RA to CD45R0 in both CD4 (P less than .05) and CD8 (P less than .001) subpopulations. These data indicate that (a) some MM T cells require significantly fewer accessory signals (if any) to express the IL-2 receptor fully, secrete IL-2, and proliferate on multivalent cross-linking of the CD3/TCR complex; and (b) this peculiar state of activation is associated with high HLA-DR expression in CD8+ lymphocytes.


2021 ◽  
Author(s):  
Yannick D. Muller ◽  
Leonardo M.R. Ferreira ◽  
Emilie Ronin ◽  
Patrick Ho ◽  
Vinh Nguyen ◽  
...  

Infusion of regulatory T cells (Tregs) engineered with a chimeric antigen receptor (CAR) targeting donor-derived human leukocyte antigen (HLA) is a promising strategy to promote transplant tolerance. Here, we describe an anti-HLA-A2 CAR (A2-CAR) generated by grafting the complementarity-determining regions (CDRs) of a human monoclonal anti-HLA-A2 antibody into the framework regions of the Herceptin 4D5 single-chain variable fragment and fusing it with a CD28-zeta signaling domain. The CDR-grafted A2-CAR maintained the specificity of the original antibody. We then generated HLA-A2 mono-specific human CAR Tregs either by deleting the endogenous T-cell receptor (TCR) via CRISPR/Cas9 and introducing the A2-CAR using lentiviral transduction or by directly integrating the CAR construct into the TCR alpha constant locus using homology-directed repair. These A2-CAR+TCRdeficient human Tregs maintained both Treg phenotype and function in vitro. Moreover, they selectively accumulated in HLA-A2-expressing islets transplanted from either HLA-A2 transgenic mice or deceased human donors. A2-CAR+TCRdeficient Tregs did not impair the function of these HLA-A2+ islets, whereas similarly engineered A2-CAR+TCRdeficientCD4+ conventional T cells rejected the islets in less than 2 weeks. A2-CAR+TCRdeficient Tregs delayed graft-versus-host disease only in the presence of HLA-A2, expressed either by co-transferred peripheral blood mononuclear cells or by the recipient mice. Altogether, we demonstrate that genome-engineered mono-antigen-specific A2-CAR Tregs localize to HLA-A2-expressing grafts and exhibit antigen-dependent in vivo suppression, independent of TCR expression. These approaches may be applied towards developing precision Treg cell therapies for transplant tolerance.


Blood ◽  
2021 ◽  
Author(s):  
Maissa Mhibik ◽  
Erika M. Gaglione ◽  
David Eik ◽  
Ellen K Kendall ◽  
Amy Blackburn ◽  
...  

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.


Blood ◽  
1982 ◽  
Vol 59 (4) ◽  
pp. 844-850 ◽  
Author(s):  
RP Witherspoon ◽  
LG Lum ◽  
R Storb ◽  
ED Thomas

Abstract Immunoglobulin secretion was studied in 37 patients between 19 and 106 days after allogeneic HLA-identical (30 patients), allogeneic one HLA- haplotype-identical (three patients), syngeneic (three patients), or autologous (one patient) marrow grafting. E rosette-positive (T) and E rosette-negative (non-T) peripheral blood mononuclear cells were cocultured with pokeweed mitogen for 6 days. Polyvalent immunoglobulin secretion was determined by counting plaque forming cells in a reverse hemolytic plaque assay. The number of antibody secreting cells in cocultures of autologous T and non-T lymphocytes was low in 40 of 44 tests conducted on samples from the 37 patients. Mononuclear or non-T cells from 38 of 40 tests failed to produce antibody when cultured with normal helper T cells. T cells from 23 of 37 tests failed to help normal non-T cells secrete antibody. T lymphocytes from 23 of 41 tests suppressed antibody production greater than 80% by normal T and non-T cells. The suppressor cells were radiosensitive in 17 of the 25 tests. The abnormal function of lymphocyte subpopulations in patients during the first 3 mo after syngeneic, allogeneic or autologous marrow grafting was similar regardless of the type of graft or the presence of acute graft versus host disease.


2019 ◽  
Vol 20 (5) ◽  
pp. 1139 ◽  
Author(s):  
Tsui Mao ◽  
Carol Miao ◽  
Yi Liao ◽  
Ying Chen ◽  
Chia Yeh ◽  
...  

γδ-T-cells have attracted attention because of their potent cytotoxicity towards tumors. Most γδ-T-cells become activated via a major histocompatibility complex (MHC)-independent pathway by the interaction of their receptor, Natural Killer Group 2 Member D (NKG2D) with the tumor-specific NKG2D ligands, including MHC class I-related chain A/B (MICA/B) and UL16-binding proteins (ULBPs), to kill tumor cells. However, despite their potent antitumor effects, the treatment protocols specifically targeting ovarian tumors require further improvements. Ovarian cancer is one of the most lethal and challenging female malignancies worldwide because of delayed diagnoses and resistance to traditional chemotherapy. In this study, we successfully enriched and expanded γδ-T-cells up to ~78% from peripheral blood mononuclear cells (PBMCs) with mostly the Vγ9Vδ2-T-cell subtype in the circulation. We showed that expanded γδ-T-cells alone exerted significant cytotoxic activities towards specific epithelial-type OVCAR3 and HTB75 cells, whereas the combination of γδ-T cells and pamidronate (PAM), a kind of aminobisphosphonates (NBPs), showed significantly enhanced cytotoxic activities towards all types of ovarian cancer cells in vitro. Furthermore, in tumor xenografts of immunodeficient NSG mice, γδ-T-cells not only suppressed tumor growth but also completely eradicated preexisting tumors with an initial size of ~5 mm. Thus, we concluded that γδ-T-cells alone possess dramatic cytotoxic activities towards epithelial ovarian cancers both in vitro and in vivo. These results strongly support the potential of clinical immunotherapeutic application of γδ-T-cells to treat this serious female malignancy.


Sign in / Sign up

Export Citation Format

Share Document