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At least 37 records · Page 2Linked to original sources
PubMed2003

Latent and lytic HHV-8 mRNA expression in PBMCs and Kaposi's sarcoma skin biopsies of AIDS Kaposi's sarcoma patients.

Human herpes virus 8 (HHV-8) is associated with all clinical forms of Kaposi's sarcoma. HHV-8 DNA is present in Kaposi's sarcoma biopsies and is observed regularly in saliva and less consistently in blood of Kaposi's sarcoma patients. The expression pattern of latent (ORF 73) and lytic (vGCR, vBcl-2, and vIL-6) HHV-8 mRNA was studied in peripheral blood mononuclear cell (PBMC) samples and Kaposi's sarcoma skin biopsies from 11 AIDS Kaposi's sarcoma patients with four different nucleic acid sequence-based amplification (NASBA) assays. Patients were divided into groups according to the clinical stage of Kaposi's sarcoma (stage I-IV). All biopsies were positive for two or more of the mRNA measured. No clear difference could be seen in the expression pattern in the lesions of the different clinical stages. In the corresponding PBMC samples, very little or no mRNA was measurable in the patients with Kaposi's sarcoma stage I or II, whereas patients with more advanced Kaposi's sarcoma (stage III or IV) had more detectable mRNA in the PBMCs. Thus, the HHV-8 DNA load in the PBMCs increases in more advanced Kaposi's sarcoma, as does the frequency of mRNA detection in PBMCs.

AIDS-Related Opportunistic Infections↗
PubMed2000

IL-4 production by PBMCs on stimulation with mite allergen is correlated with the level of serum IgE antibody against mite in children with bronchial asthma.

BACKGROUND: Although IL-4, IL-13, and IFN-gamma are known to affect IgE synthesis, it remains unclear which one plays the most important role in in vivo IgE synthesis in atopic patients. OBJECTIVE: The aim of this study is to clarify the difference in importance among these cytokines in up-regulation of IgE synthesis in atopic patients. METHODS: We measured IL-4, IL-13, and IFN-gamma production by PBMCs on stimulation with house dust mite (HDM) in 23 children, 3 to 15 years old, with bronchial asthma (BA) and analyzed the correlation with HDM-specific IgE antibody levels expressed as HDM IgE radioallergosorbent test (RAST) results. RESULTS: The production of IL-4 and IL-13 by PBMCs on stimulation with HDM was significantly higher in children with BA than in nonatopic control subjects (IL-4, 752.9 +/- 365.9 vs 312.3 +/- 230.0 fg/mL, P <.001; IL-13, 21.9 pg/ml [<12.0-77.6] vs <12.0, P <.01). IL-4 production showed a close positive correlation with HDM IgE RAST (r = 0.71, P <.001), which was distinctly stronger than that between IL-13 production and HDM IgE RAST (r = 0.46, P <.05). IFN-gamma production was neither different between children with BA and nonatopic control subjects (7. 24 [1.54-33.90] pg/mL vs 11.2 [1.66-75.9] pg/mL) nor correlated with HDM IgE RAST levels. Essentially the same result was obtained by stimulation of PBMCs with a purified HDM major allergen Der f 1. CONCLUSION: IL-4 is likely to be the most important cytokine in up-regulation of in vivo IgE synthesis against HDM in children with BA.

Adolescent↗
PubMed2000

Induction of corticosteroid insensitivity in human PBMCs by microbial superantigens.

BACKGROUND: Microbial superantigens have been described to contribute to the pathogenesis of chronic inflammatory diseases often complicated by insensitivity to glucocorticoid therapy. In bronchial asthma glucocorticoid insensitivity has been associated with increased expression of glucocorticoid receptor beta, an endogenous inhibitor of the classic glucocorticoid receptor alpha. OBJECTIVE: To study a potential mechanism by which superantigens could contribute to poor disease control, we examined their capacity to alter steroid sensitivity and expression of glucocorticoid receptor beta. METHODS: The capacity of dexamethasone to inhibit stimulation of PBMCs from 7 healthy subjects with the prototypic superantigens, staphylococcal enterotoxin (SE) B, toxic shock syndrome toxin (TSST)-1 and SEE, versus PHA, was tested. The expression of glucocorticoid receptor beta in normal PBMCs after stimulation with SEB, versus PHA, was assessed by immunocytochemistry. RESULTS: Dexamethasone 10(-6) mol/L caused a 99% inhibition of PHA-induced PBMC proliferation but only a 19% inhibition of the SEB-induced, 26% inhibition of the TSST-1, and 29% inhibition of the SEE-induced PBMC proliferation (P <.01 for all superantigens versus PHA) demonstrating that superantigens can induce steroid insensitivity. Stimulation of normal PBMCs with SEB induced a significant increase of glucocorticoid receptor beta compared with PHA and unstimulated cells (P <.01). CONCLUSION: We have demonstrated the capacity of microbial superantigens to induce glucocorticoid insensitivity, which should be considered in the diagnosis and treatment of patients with superantigen-triggered diseases. These data suggest that superantigens may contribute to glucocorticoid insensitivity through induction of glucocorticoid receptor beta.

Asthma↗
PubMed2004

Immunomodulating effects of CKBM on the cytokine production in peripheral blood mononuclear cells (PBMCs) from healthy volunteers.

The current study investigated the immunomodulating effect of CKBM on cytokine induction in peripheral blood mononuclear cells (PBMCs) isolated from 20 healthy volunteers. Cytometric Bead Analysis (CBA) was used to study IL-2, IL-4, IL-6, IL-10, TNF-alpha and IFN-gamma. TNF-alpha and IL-6 were significantly increased in a CKBM dose- and time-dependent manner. Flow cytometry analysis showed an increased intracellular staining of IL-6 but not of TNF-alpha in CKBM treated PBMCs. In addition, MTT cell cytotoxicity assay showed that CKBM concentrations below 5% did not significantly affect the metabolic activities of PBMCs. The current study indicated that CKBM may modulate the immune response by inducing the secretions of TNF-alpha and IL-6, which are cytokine mediators of innate immunity and inflammation preparing or "priming" the body to combat diseases.

Adult↗
PubMed2004

The non-classical HLA class I molecule HFE does not influence the NK-like activity contained in fresh human PBMCs and does not interact with NK cells.

In humans, four beta2-microglobulin-associated non-classical class I molecules are encoded in the MHC: HLA-E, -F, -G and -H. Three of them (HLA-E, -F and -G) were shown to inhibit NK activity. On the contrary, the fourth one, HLA-H, named HFE after it was found to be mutated in patients suffering from inherited hemochromatosis, has been shown to be involved only in the regulation of iron uptake. We tested the capacity of HFE to affect (enhance or reduce) specifically the NK activity contained in non-manipulated fresh human PBMCs. We showed that HFE expression by target cells does not affect their killing by the NK-like activity contained in PBMCs. Moreover, using fluorescent HFE tetramers, we could confirm that blood NK cells as well as blood gammadelta T cells do not bind HFE. Altogether, our data indicate that HFE does not affect the NK activity contained in the PBMCs.

Animals↗
PubMed2005

Ribavirin up-regulates IL-12 p40 gene expression and restores IL-12 levels in Leishmania-treated PBMCs.

Ribavirin, a nucleoside analogue that interferes with viral mRNA synthesis and inhibits the replication of RNA and DNA viruses, has been recently proposed as an effective immune response modulator. In the present report, we studied the effect of ribavirin on IL-12 p40 gene expression in peripheral blood mononuclear cells (PBMCs) of healthy subjects. We also studied ribavirin effects on PBMCs activated with lipopolysaccharide (LPS) and phytohaemagglutinin (PHA) and treated with Leishmania donovani antigens. We provide evidence that ribavirin was able to up-regulate IL-12 p40 gene expression and to restore levels of IL-12 p40 gene expression and IL-12 secretion in fully activated PBMCs that were strongly inhibited by L. donovani antigens. Because effective management of leishmanial disease is usually associated with a prevalent T-helper 1 immune response with elevated production of IL-12,our preliminary results may be of particular interest, provided that they will be confirmed by further in vitro and in vivo studies, when considering a possible use of ribavirin as adjuvant in severe leishmanial disease.

Adolescent↗
PubMedDate not supplied

RT-PCR analysis of immune-modulating factors in PBMCs from patients with cancer: reduced IL-2 and increased IL-2-receptor (p55) expression characterize gastroenteric neoplasms.

BACKGROUND: To determine the potential contribution of cytokines associated with lymphocyte activation to the pathogenesis of immune impairment in gastroenteric cancer, we examined the expression of cytokine mRNA in peripheral blood mononuclear cells (PBMCs) and tumor-draining lymph nodes (LNs). MATERIAL AND METHODS: Using a reverse transcriptase-polymerase chain reaction (RT-PCR) technique, mRNA transcripts for interleukin (IL)-4, IL-2, IL-5, IL-6, IL-1 beta, IFN gamma, IL-10 and IL-2-receptor(IL-2R)(p55) were detected in PBMCs from 16 patients with gastroenteric cancer, undergoing surgical resection, and from 13 healthy donors. RESULTS: Patients expressed a different pattern of cytokines. Significantly increased IL-2R(p55) and reduced IL-2 mRNA expression were found in patients (p = 0.034, p = 0.043). IL-10 expression was significantly correlated to IL-2R(p55) expression in both groups (p = 0.011, p = 0.009). In LNs, the results reflected those from PBMCs of the same patient. CONCLUSIONS: Gastroenteric cancer showed a suppressive pattern of cytokine expression, suggesting an impairment of T cell activation that can be evidenced from the specific pattern of PBMC cytokine expression.

Aged↗
PubMed2003

Two ways to induce innate immune responses in human PBMCs: paracrine stimulation of IFN-alpha responses by viral protein or dsRNA.

In order to study mechanisms of induction of IFN-alpha by Newcastle disease virus (NDV), we used two replicon systems which are based respectively on DNA and RNA of the Semliki forest virus (SFV) and transfected these into baby hamster kidney cells (BHK) which do not produce interferon-alpha. Co-incubation of BHK cells which were transfected with the two vector systems, with human PBMCs, showed that production of IFN-alpha takes place by two different ways. When using the DNA-based SFV vector, only transfectants expressing cell surface HN molecules of NDV (and not the mock-transfected cells) elicited such a response via interaction of these HN molecules with viral receptors on PBMCs. In contrast, BHK cells transfected with RNA which had been in vitro transcribed from the RNA-based SFV vector without foreign gene as insert (mock-transfected) elicited a comparable IFN-alpha response. Transfer by transfection of poly(I:C), an analogue of double stranded RNA (dsRNA), into the BHK cells induced also by itself the production of IFN-alpha. Therefore induction of "danger signals" (as double-strand RNA replicative intermediates) might be responsible for this discrepancy observed in IFN-alpha induction in PBMCs between the two studied SFV vector systems based on transfection of DNA and on RNA. These observations highlight two ways of IFN-alpha induction which additively may explain the high interferonogenic capacity of NDV as virus: i) via cell-surface expressed HN after transfection of the DNA-based SFV replicon and ii) via transfection of self-amplifying RNA.

Animals↗
PubMed2004

The role of innate immune cells in the response of heat-treated Mycobacterium tuberculosis (M.tb) antigens stimulating PBMCs.

The proliferation response of gammadelta T cells to the antigen from heat-treated Mycobacterium tuberculosis H37Ra (M.tb Ag) was used as a good model in gammadeltaT cell research. From preliminary research it is found that activated NK cells positively elevated gammadeltaT cells proliferation after simulating PBMCs with M.tb Ag. To investigate different behaviors of NK cells, gammadeltaNKT cells, gammadeltaT cells and relationships between these cell subsets, activation and proliferation of different cell subsets of PBMCs in response to M.tb Ag were analyzed. We demonstrated that NK cells, gammadeltaNKT cells and gammadeltaT cells could be activated after stimulation with M.tb Ag. gammadeltaNKT cells and gammadelta T cells proliferated while the number of NK cells decreased after 11 day-simulation with M.tb Ag. Meanwhile, at the early time of stimulation the cytotoxicity of PBMCs was enhanced.

Antigens, Bacterial↗
PubMed2006

[Expression map of immune-related genes on PBMCs in familial clustering patients with chronic virus hepatitis B].

AIM: To investigate peripheral blood mononuclear cells (PBMCs) immune-related gene expression profile in patients with chronic virus hepatitis B(CHB) by oligonucleotide gene array technique. METHODS: PBMCs were collected from the members of a family of clustering hepatitis B virus (HBV) infection including 5 CHB patients and 4 healthy spouses and RNA prepared from PBMCs was hybridized to high-density oligonucleotide arrays(HG-U133A 2.0 Human Gene Chips, Affymetrix), covering the expression of 22 000 human ESTs. Primary scanned image was analyzed with DNT software package. RESULTS: Out of the 22 000 ESTs, 24 different immune-related genes were identified. Among the 24 genes, 7 genes showed increased expression and 17 genes showed decreased expression in CHB compared with those in healthy spouses. The up-regulated genes were mainly associated with adaptive immunity, while the down-regulated genes were associated with innate immunity. CONCLUSION: Our findings suggest that HBV infection alters a broad range of immunity genes expression and innate immunity-associated genes are important in the defense against HBV chronic infection.

Down-Regulation↗
PubMed1996

Cytokine mRNA levels in unmanipulated (ex vivo) and in vitro stimulated monkey PBMCs using a semi-quantitative RT-PCR and high sensitivity fluorescence-based detection strategy.

To investigate the spectrum of cytokines expressed by peripheral blood mononuclear cells (PBMC) from cynomolgus macaques (Macaca fascicularis), we used a semi-quantitative RT-PCR to determine levels of mRNA coding for IL-1 beta, IL-2, IL-4, IL-6, IL-10, IFN-gamma, and TNF-alpha. The PCR products were labelled and quantified using a new fluorescent tag TOTO-1 (thiazole orange dimer) and an automated fluorescence-based electrophoretic instrument. Using this assay, the base line levels of cytokine mRNA expression in unmanipulated PBMCs (ex vivo) from 10 healthy monkeys were compared with the mRNA levels for the same cytokines in PBMC samples from two pre-immunized monkeys following culture with previously defined optimal concentrations of purified protein derivative (PPD), tetanus toxoid (TT) and the mitogen concanavalin A (con-A). While transcripts or IL-2, IL-4 and IFN-gamma were either low or not detected in unmanipulated PBMCs, varying levels of IL-1 beta, IL-5, IL-10, and TNF-alpha were readily detected in the same samples. With the exception of IL-10, the mitogen con-A induced the highest levels of cytokine expression, followed by levels induced by culture with TT. The levels of cytokine expression induced by PPD however, were not significantly elevated, despite the fact that the cells showed marked proliferative responses. This assay is a simple and convenient method for evaluating the levels of cytokine expression in small PBMC samples and will allow for the concurrent evaluation of immune profiles with functional immune analyses.

Animals↗
PubMed2000

Increased levels of apoptosis of leukocyte subsets in cultured PBMCs compared to whole blood as shown by Annexin V binding: relevance to cytokine production.

Most of the investigatory studies of cytokine production by cells have been performed on purified cells or cell lines by measuring the secreted cytokine levels in the bulk culture supernatant. However, results of cytokine production from isolated peripheral blood mononuclear cells (PBMCs) cultivated in synthetic media, have been reported to be inaccurate and of low reproducibility. Isolation procedures have been shown to be toxic to certain cells. We hypothesised that purified cell culture techniques may result in increased levels of apoptosis of cells compared with whole blood culture techniques. To compare the effects on cell viability between PBMCs and whole blood techniques, an Annexin V binding assay was utilised. The effect of different cell concentration and serum/plasma concentrations on apoptosis levels in the various leukocyte subsets in PBMC and whole blood cultures following stimulation was investigated. There were significantly increased levels of apoptosis of cells in PBMC compared to whole culture at similar plasma concentrations, suggesting that cell viability was plasma concentration-dependent. There were significantly increased levels of apoptosis in PBMC cultures at the same cell concentration to whole blood techniques, suggesting that interaction between all cellular elements (as in whole blood techniques) is important in maintaining cell viability. These results suggest that whole blood culture techniques provide the best conditions for study of leukocyte cytokine production. If PBMC culture is performed, similar plasma and cell concentration to whole blood will best preserve cell viability.

Adult↗
PubMed2005

The HLA-G genotype is associated with IL-10 levels in activated PBMCs.

Human leukocyte antigen (HLA)-G is an MHC class Ib molecule that is expressed at the feto-maternal interface during pregnancy. However, recent results have also shown that it may have important functions as an immuno-modulatory factor in adult life. Differences in the pattern of alternative splicing and in the stability of HLA-G mRNA transcripts have been associated with HLA-G polymorphisms, especially a 14 bp deletion/insertion polymorphism in the 3' untranslated region of the HLA-G gene. We have investigated the secretion of HLA-G5/soluble HLA-G1 and interleukin-10 (IL-10) in lipopolysaccharide (LPS)-activated peripheral blood mononuclear lymphocytes (PBMCs) in relation to the HLA-G 14 bp genotype. No HLA-G5/sHLA-G1 could be detected in the non-activated control PBMC culture media, and there were no significant differences among the three HLA-G 14 bp genotypes regarding IL-10 concentrations. In LPS-activated PBMC cultures, no significant differences among the three HLA-G 14 bp genotypes regarding HLA-G5/sHLA-G1 concentrations were observed. However, this was in contrast to the IL-10 levels (P=0.0004, Kruskal-Wallis test). The +14/+14 bp PBMC samples expressed higher levels of IL-10 when compared to the -14/+14 bp genotype and the -14/-14 bp genotype. Interestingly, the IL-10 G/G polymorphism at position -1082 was more frequent in the +14/+14 bp genotype (P=0.024, chi2 test). These results support an autocrine loop between HLA-G5/sHLA-G1 and IL-10 expression in activated PBMCs, which may result in higher IL-10 levels in +14/+14 bp HLA-G genotypes.

3' Untranslated Regions↗
PubMed2004

Emissions from indoor dust inhibit proliferation of A549 cells and TNFalpha release from stimulated PBMCs.

Dust accumulating on hot indoor surfaces, e.g., heaters and light fixtures, are likely to emit chemicals when heated. Using in vitro techniques we have investigated biological effects of extracts from such emissions from three indoor and two outdoor dust samples heated at 50-250 degrees C. The cell cultures were a lung epithelial cell line (A549) and primary immune cells [peripheral blood mononuclear cell (PBMCs)]. We found that a 24-h incubation with extracts generated at 200 degrees C or higher inhibit both proliferation and mitochondrial activity of the epithelial cells. At non-cytotoxic concentrations, the extracts generated at 100 degrees C or higher inhibit the release of the pro-inflammatory cytokine tumor necrosis factor-alpha (TNFalpha) from lipopolysaccharide-stimulated PBMCs. The results imply that temperatures relevant for surfaces of equipment in the indoor environment cause emissions from dust that may have an impact on indoor air quality and affect the respiratory health of building occupants.

Air Pollution, Indoor↗
PubMed2003

Sequence analysis of EBV DNA isolated from mouth washings and PBMCs of healthy individuals and blood of EBV-LPD patients.

BACKGROUND: Lymphoproliferative disorder (LPD) caused by Epstein-Barr virus (EBV) is a severe complication of bone marrow transplantation. The EBV strain causing LPD is of either donor or recipient origin, however, available data are limited to only a small number of cases. To obtain solid evidence, comparison of the EBV strain that caused the EBV-LPD with pre-stem cell transplantation (SCT) EBV strains of donor and recipient is imperative. Available techniques rely on the production of EBV transformed lymphoblastoid cell lines and lack sensitivity. OBJECTIVE: The aim of this study was to develop a simple method for EBV sequence analysis on mouth washings (MWs) and peripheral blood mononuclear cells (PBMCs). STUDY DESIGN: EBV DNA was extracted from MWs and PBMCs that were collected from 20 healthy individuals. DNA was used for sequence analysis, using a polymerase chain reaction for the C-terminus of the LMP-1 gene. RESULTS: In seropositive individuals EBV DNA could be detected in 11/14 (79%) MWs and in 13/14 (93%) PBMC samples. Sequence analysis showed that in 11 out of 14 (79%) healthy individuals sequence patterns could be established. In these 11 healthy individuals 13 sequence patterns could be detected. Eleven of these 13 patterns (84.6%) were unique. These results encouraged us to explore the feasibility of this method on EBV DNA isolated from plasma from 9 EBV-LPD patients at time of EBV reactivation. In 7 EBV-LPD patients 8 sequence patterns were detected. Six out of 8 sequence patterns (75%) were unique. CONCLUSION: Our method is suitable for strain identification and we intend to use this technique to evaluate EBV origin in EBV-LPD patients.

Adult↗
PubMed2002

The lipid raft microdomain-associated protein reggie-1/flotillin-2 is expressed in human B cells and localized at the plasma membrane and centrosome in PBMCs.

Reggie-1/flotillin-2 is a plasma membrane-associated cytoplasmic protein, which defines non-caveolar raft microdomains. Reggie-1/flotillin-2 is enriched in detergent insoluble (TX100) membrane fractions (DIG), co-localizes with activated GPI-linked proteins and the fyn-kinase in neurons and T cells, and thus apparently participates in the assembly of protein complexes essential for signal transduction. In T cells activated by crosslinking the GPI-linked protein Thy-1 or by crosslinking the ganglioside GM1, reggie-1/flotillin-2 co-localizes with the T cell receptor. To determine whether reggie-1/flotillin-2 is also expressed in B cells, primary B cells from human blood and cell lines representing the developmental stages of pro, pre, mature and plasma B cells were analyzed by Western blotting, RT-PCR and immunofluorescence. Here, we show that reggie-1/flotillin-2 is expressed throughout B cell development, as well as in primary B cells, purified by cell sorting. On non-activated mature B cell Raji cell line we found reggie-1/flotillin-2 are exclusively in the detergent (TX100) insoluble membrane fractions that are staining positive for the raft marker GM1. Immunofluorescence microscopy showed that reggie-1/flotillin-2 is localized at the plasma membrane and marks intracellular spots in PBMCs. Confocal co-localization studies showed that reggie-1/flotillin-2 is associated with the plasma membrane, and the centrosomes (microtubule organizing centers) in these PBMCs. Comparison of reggie-1/flotillin-2 cDNA sequences with the genomic sequence database allowed us to determine the exon/intron structures in mouse and human. The gene organizations are highly conserved suggesting an important function of reggie-1/flotillin-2. Since reggie/flotillin proteins co-cluster with the T cell receptor and fyn kinases upon T cell stimulation, our findings of reggie-1/flotillin-2 in B cells suggest a similar role in B cell function.

Animals↗
PubMed2026

Characterization of DNA methylation in PBMCs and donor-matched iPSCs shows age-related methylation is reset during stem cell reprogramming.

DNA methylation is an important epigenetic mechanism that helps define and maintain cellular functions. It is influenced by many factors, including environmental exposures, genotype, cell type, sex, and aging. Since age is the primary risk factor for developing neurodegenerative diseases, it is important to determine if age-related DNA methylation is retained when cells are reprogrammed to an induced Pluripotent Stem Cell (iPSC) state. Here, we selected peripheral blood mononuclear cells (PBMCs; n&#x2009;=&#x2009;99) from a cohort of diverse and healthy individuals enrolled in the Genetic and Epigenetic Signatures of Translational Aging Laboratory Testing (GESTALT) study to reprogram to iPSCs. After reprogramming, the resulting iPSCs were evaluated for DNA methylation signatures to determine if they reflect the confounding factors of aging and environmental effects. Data from genome-wide DNA methylation arrays in both cell types showed that age-related methylation measured by epigenetic clocks is largely reset to an early methylation age after reprogramming of PBMCs to iPSCs. We further examined the epigenetic age of each cell type using an Epigenome-wide Association Study (EWAS) and identified a set of methylation Quantitative Trait Loci in each cell type. Our results show that age-related DNA methylation is largely reset in iPSCs, and each cell type has a unique set of methylation sites that are modified by population-level genetic variation.

DNA Methylation↗
PubMed2004

Therapeutic polypeptides based on HBV core 18-27 epitope can induce CD8+ CTL-mediated cytotoxicity in HLA-A2+ human PBMCs.

AIM: To explore how to improve the immunogenicity of HBcAg CTL epitope based polypeptides and to trigger an HBV-specific HLA I-restricted CD8+ T cell response in vitro. METHODS: A new panel of mimetic therapeutic peptides based on the immunodominant B cell epitope of HBV PreS2 18-24 region, the CTL epitope of HBcAg18-27 and the universal T helper epitope of tetanus toxoid (TT) 830-843 was designed using computerized molecular design method and synthesized by Merrifield's solid-phase peptide synthesis. Their immunological properties of stimulating activation and proliferation of lymphocytes, of inducing T( H1) polarization, CD8+ T cell magnification and HBV-specific CD8+ CTL mediated cytotoxicity were investigated in vitro using HLA-A2+ human peripheral blood mononuclear cells (PBMCs) from healthy donors and chronic hepatitis B patients. RESULTS: Results demonstrated that the therapeutic polypeptides based on immunodominant HBcAg18-27 CTL, PreS2 B- and universal T(H) epitopes could stimulate the activation and proliferation of lymphocytes, induce specifically and effectively CD8+ T cell expansion and vigorous HBV-specific CTL-mediated cytotoxicity in human PBMCs. CONCLUSION: It indicated that the introduction of immunodominant T helper plus B-epitopes with short and flexible linkers could dramatically improve the immunogenicity of short CTL epitopes in vitro.

Amino Acid Sequence↗