Search results for "CD8"
showing 10 items of 682 documents
Rapid High Efficiency Sensitization of CD8+ T Cells to Tumor Antigens by Dendritic Cells Leads to Enhanced Functional Avidity and Direct Tumor Recogn…
2003
Abstract Myeloid-origin dendritic cells (DCs) can develop into IL-12-secreting DC1 or non-IL-12-secreting DC2 depending on signals received during maturation. Through rapid culture techniques that prepared either mature, CD83+ DC1 or DC2 from CD14+ monocytes in only 2 days followed by a single 6–7 day DC-T cell coculture, we sensitized normal donor CD8+ T cells to tumor Ags (HER-2/neu, MART-1, and gp100) such that peptide Ag-specific lymphocytes constituted up to 16% of the total CD8+ population. Both DC1 and DC2 could sensitize CD8+ T cells that recognized peptide-pulsed target cells. However, with DC2, a general decoupling was observed between recognition of peptide-pulsed T2 target cells…
MHC-unrestricted recognition of bacteria-infected target cells by human CD8+ cytotoxic T lymphocytes.
1992
Abstract A CD8 + αβTCR + T cell clone (A35) was isolated from the synovial fluid of a patient with postenteric reactive arthritis caused by Yersinia enterocolitica . This clone efficiently killed autologous and allogeneic target cells that had been preincubated with live but not with heat-killed bacteria. There was no restriction by polymorphic parts of HLA-A, -B. or -C molecules and a HLA class II-deficient mutant cell line was lysed as efficiently as its normal counterpart, whereas infected HLA class I-deficient cells (Daudi cells) were not. The clone showed crossreaction between Yersinia enterocolitica , Escherichia coli , Pseudomonas aeruginosa , and Streptococcus pyogenes , but did not…
Genome-based in silico identification of new Mycobacterium tuberculosis antigens activating polyfunctional CD8+ T cells in human tuberculosis.
2011
Although CD8(+) T cells help control Mycobacterium tuberculosis infection, their M. tuberculosis Ag repertoire, in vivo frequency, and functionality in human tuberculosis (TB) remains largely undefined. We have performed genome-based bioinformatics searches to identify new M. tuberculosis epitopes presented by major HLA class I supertypes A2, A3, and B7 (covering 80% of the human population). A total of 432 M. tuberculosis peptides predicted to bind to HLA-A*0201, HLA-A*0301, and HLA-B*0702 (representing the above supertypes) were synthesized and HLA-binding affinities determined. Peptide-specific CD8(+) T cell proliferation assays (CFSE dilution) in 41 M. tuberculosis-responsive donors ide…
Selective Depletion of Alloreactive T Lymphocytes Using Patient-Derived Nonhematopoietic Stimulator Cells in Allograft Engineering
2008
Background. Selective depletion of alloreactive T cells in vitro results in efficient graft-versus-host disease prophylaxis in allogeneic hematopoietic stem-cell transplantation, but it is accompanied by increased recurrence of leukemia. To spare donor T-cell-mediated graft-versus-leukemia immunity against hematopoiesis-restricted minor histocompatibility (minor-H) antigens, we explored the use of patient-derived nonhematopoietic antigen-presenting cells (APC) as allogeneic stimulators for selective allodepletion in leukemia-reactive donor T-cell lines. Methods. Primary keratinocytes, dermal fibroblasts, and bone marrow fibroblasts were generated from skin biopsies and diagnostic bone marro…
Evaluation of serum levels of soluble CD4, CD8 and β2-microglobulin in visceral human leishmaniasis
1994
SUMMARY The levels of soluble CD4 (sCD4), sCD8 and β2-microglobulin (β2-M) were measured in sera from patients with visceral leishmaniasis during the course of infection. Levels of sCD4. sCD8 and β2-M were raised significantly above levels In normal sera and returned to the normal range after recovery. The decrease in the levels of CDS was related to a reduction of anaemia, leukopenia and thrombocytopenia. In contrast, sCD4 levels fluctuated during the period of infection. β2-M returned within normal range more rapidly than sCD8 secretion. Our results suggest that T cells are activated during infection, and that it is also possible that the raised levels of these soluble molecules play a ro…
Hepatitis C virus-specific T-cell-derived transforming growth factor beta is associated with slow hepatic fibrogenesis.
2011
Up to 4 million persons in the USA have chronic hepatitis C (CHC) (1). Despite a decline in overall HCV infections, the number of patients with end stage liver disease due to CHC will increase for the next 2 decades (2). Even with highly effective novel therapies, currently 30–50% of infected individuals fail treatment (3). Therefore, a better understanding of mechanisms involved in CHC-related liver disease progression could permit more efficient therapies. Adaptive effector T cells (frequently assessed by measuring production of prototypic T helper 1 cytokine IFNγ) play an important role in control of HCV infection during the acute phase (4). In CHC, effector HCV-specific T cell immune re…
Correlation of Clinical and Immunologic Parameters of the Inflammatory Activity of Pulmonary Sarcoidosis
1991
The evaluation of activation markers such as T4/T8 ratio and HLA-DR expression of lymphocytes of bronchoalveolar lavage (L-BAL) is an important clinical approach for the staging of sarcoidosis. However, it is not known to what extent this is paralleled by an exaggerated lymphocyte function. We investigated the dependence of L-BAL activation markers on the production of interleukin-2 (IL-2) by L-BAL and on the soluble IL-2 receptor serum level (sIL-2R) in 116 patients with sarcoidosis. In none of the combinations tested was a correlation between the two groups of parameters found; r less than 0.5, upper 90% confidence limit of r less than 0.8. Interestingly, IL-2 production is independent of…
Spontaneous Monokine Release by Alveolar Macrophages in Chronic Sarcoidosis
1991
In pulmonary sarcoidosis an activation of alveolar T lymphocytes and alveolar macrophages (AM) has been demonstrated. There is evidence that in contrast to acute disease a heightened T-cell response cannot be observed in the chronic phase of sarcoidosis. The role of AM in the inflammatory process of chronic sarcoidosis is not yet intensively evaluated. To address this question we measured the release of tumor necrosis factor alpha (TNFα) and interleukin-1 (IL-1) by AM of 39 patients with chronic sarcoidosis (duration > 4 years; 30 active, 9 inactive diseases) without therapy and correlated the monokine release with parameters of T-cell alveolitis and the course of the disease. The T4/T8 …
B and T cell immune responses elicited by the Comirnaty® COVID-19 vaccine in nursing home residents
2021
Objectives The immunogenicity of the Comirnaty® COVID-19 vaccine is understudied in elderly people with comorbidities. SARS-CoV-2-S-targeted antibody and T cell responses following full vaccination were assessed in nursing home residents. Methods Sixty nursing home residents (44 female; age, 53-100 years), of whom 10 had previously been diagnosed of COVID-19, and 18 healthy controls (15 female; age, 27-54 years) were recruited. Pre- and post-vaccination blood specimens were available for quantitation of total antibodies binding SARS-CoV-2 S protein and enumeration of SARS-CoV-2-S-reactive IFN-γ CD4+ and CD8+ T cells by flow cytometry. Results The seroconversion rate in presumably SARS-CoV-2…
Anti-Anisakis sp. antibodies in serum of healthy subjects. Relationship with αβ and γδ T cells
2016
Anisakiosis is nowadays one of the nematodoses more prevalent in Spain, with rates that oscillate between 0.43% in Galicia (N.W. Spain), and 15.7% and 22.1% in inland and southern regions, respectively. Likewise, it has been proved that Anisakis larvae have developed mechanisms to modulate the dichotomy of the host immune response for their own benefit. The experimental hypothesis of the present study was that Anisakis sp. larval products can be mediators of immune suppression and induce changes on the populations of αβ+ and γδ+ T cells. In the present study we determined the levels of anti-Anisakis antibodies in the serum of healthy people, and their relationship with the B and T cell subs…