Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 16 de 16
Filter
1.
Scand J Public Health ; : 14034948231197453, 2023 Sep 13.
Article in English | MEDLINE | ID: mdl-37705349

ABSTRACT

AIMS: Studies of the association between self-rated health and persons' income and education have almost invariably shown that people with higher education and incomes report better health. Less is known of the influence of household members' socioeconomic characteristics on individuals' health. This study thus aimed to assess the extent to which the socioeconomic characteristics of partners may contribute to explaining the variation in the respondents' self-rated health (SRH). METHODS: Using an observational design, we analysed cross-sectional Norwegian survey data on SRH (2015 and 2019), linked to register data on education and income for respondents (N = 7082) and their opposite-sex coresident spouse or partner. We employed logistic regression models to assess the associations between respondents' SRH and the relative income and education of their partner. Average marginal effects were calculated to enable cross-model comparisons. RESULTS: Net of individual characteristics, having a higher-educated partner was positively associated with SRH for both male (OR = 1.56) and female (OR = 1.36) respondents. Having a partner with an above median income (by age and sex) was positively associated with SRH for female (OR = 1.29) respondents only. For education, the positive SRH associations were roughly similar for respondents and partners. For income, the associations were more pronounced for respondents than partners. CONCLUSIONS: Our findings suggest that health is affected by the resources (or lack thereof) in one's immediate networks. To reduce social inequalities in health, health personnel might customise interactions to account for household resources. Such knowledge could also be used in health-promoting activities to enhance participation and health competency.

2.
Am J Cardiol ; 169: 64-70, 2022 04 15.
Article in English | MEDLINE | ID: mdl-35090696

ABSTRACT

It is previously shown that cardiovascular conditions have a negative effect on the ability to work. However, it is unknown if incident atrial fibrillation (AF) influences the ability to work. We examined the association between AF and the risk of work disability and the influence of socioeconomic factors. All Danish residents with a hospital diagnosis of AF and aged ≥30 and ≤63 years in the period January 1, 2000, to September 31, 2014, were included and matched 1:10 with an AF-free gender and age-matched random person from the general population. Permanent social security benefit was used as a marker of work disability. Risk difference (RD) and 95% confidence interval (95% CI) of work disability were calculated over 15 months. The analyses were furthermore stratified in low, medium, and high levels of socioeconomic factors. In total, 28,059 patients with AF and 312,667 matched reference persons were included. The risk of receiving permanent social security benefits within 15 months was 4.5% (4.3% to 4.8%) for the AF cohort and 1.3% (95% CI 1.3% to 1.4%) for the matched reference cohort. Adjusted RD (95% CI) was 2.3% (2.0% to 2.5%). Stratified on income, RDs were higher in low-income groups (adjusted RD 3.7% [95% CI 3.1% to 4.3%]) versus high-income groups (RD 1.3% [1.0% to 1.5%]). In conclusion, the risk of work disability within 15 months after incident AF was more than 3 times as high in patients with AF compared with the general population, especially when comparing individuals in lower socioeconomic strata.


Subject(s)
Atrial Fibrillation , Disabled Persons , Atrial Fibrillation/diagnosis , Atrial Fibrillation/epidemiology , Cohort Studies , Denmark/epidemiology , Humans , Incidence , Risk Factors
3.
BMJ Open ; 11(5): e048839, 2021 05 31.
Article in English | MEDLINE | ID: mdl-34059516

ABSTRACT

OBJECTIVE: The study aimed to examine the association between socioeconomic factors (SEFs) and oral anticoagulation (OAC) therapy and whether it was influenced by changing guidelines. We hypothesised that inequities in initiation of OAC reduced over time as more detailed and explicit clinical guidelines were issued. DESIGN: Register-based observational study. SETTINGS: All Danish patients with an incident hospital diagnosis of atrial fibrillation (AF), aged ≥30 years old and with high risk of stroke from 1 May 1999 to 2 October 2015 were included. Absolute risk differences (RD) (95% CI) were used to measure the association. PARTICIPANTS: 154 448 patients (mean age 78.2 years, men 47.3%). EXPOSURE: Education, family income and cohabiting status were the SEFs used as exposure. OUTCOME: A prescription of OAC within -30 to +90 days of baseline (incident AF). RESULTS: During 2002-2007, the crude RD of initiation of OAC for men with high education was 14.9% (12.8 to 16.9). Inequality reduced when new guidelines were published, and in 2013-2016 the crude RD was 5.6% (3.5 to 7.7). After adjusting for age, the RD substantially reduced. The same pattern was seen for cohabiting status, while inequality was smaller and more constant for income. CONCLUSION: Patients with low income, low education and living alone were associated with lower chance of being initiated with OAC. For education and cohabiting status, the crude difference reduced around 2011, when more detailed clinical guidelines were implemented in Denmark. Our results indicate that new guidelines might reduce inequality in OAC initiation and that new, high-cost drugs increase inequality.


Subject(s)
Atrial Fibrillation , Stroke , Administration, Oral , Adult , Aged , Anticoagulants/therapeutic use , Atrial Fibrillation/drug therapy , Humans , Male , Risk Factors , Socioeconomic Factors , Stroke/drug therapy , Stroke/epidemiology , Stroke/prevention & control
4.
Vaccine ; 39(11): 1583-1592, 2021 03 12.
Article in English | MEDLINE | ID: mdl-33612340

ABSTRACT

Targeted delivery of antigen to antigen-presenting cells (APCs) enhances antigen presentation and thus, is a potent strategy for making more efficacious vaccines. This can be achieved by use of antibodies with specificity for endocytic surface molecules expressed on the APC. We aimed to compare two different antibody-antigen fusion modes in their ability to induce T-cell responses; first, exchange of immunoglobulin (Ig) constant domain loops with a T-cell epitope (Troybody), and second, fusion of T-cell epitope or whole antigen to the antibody C-terminus. Although both strategies are well-established, they have not previously been compared using the same system. We found that both antibody-antigen fusion modes led to presentation of the T-cell epitope. The strength of the T-cell responses varied, however, with the most efficient Troybody inducing CD4 T-cell proliferation and cytokine secretion at 10-100-fold lower concentration than the antibodies carrying antigen fused to the C-terminus, both in vitro and after intravenous injection in mice. Furthermore, we exchanged this loop with an MHCI-restricted T-cell epitope, and the resulting antibody enabled efficient cross-presentation to CD8 T cells in vivo. Targeting of antigen to APCs by use of such antibody-antigen fusions is thus an attractive vaccination strategy for increased activation of both CD4 and CD8 peptide-specific T cells.


Subject(s)
CD4-Positive T-Lymphocytes , Epitopes, T-Lymphocyte , Animals , Antigen Presentation , Antigen-Presenting Cells , CD8-Positive T-Lymphocytes , Mice
5.
Diabetes Res Clin Pract ; 170: 108517, 2020 Dec.
Article in English | MEDLINE | ID: mdl-33096186

ABSTRACT

AIMS: To test the performance of the cardiac vagal tone (CVT) derived from a 5-minute ECG recording compared with the standardized cardiovascular autonomic reflex tests (CARTs). METHODS: Cross-sectional study included 56 well-phenotyped adults with type 1 diabetes (19-71 years, 2-54 years disease-duration). Autonomic testing included: standardized CARTs obtained with the VAGUS™, CVT, and indices of heart rate variability (HRV) obtained at 24- and 120-hour, and electrochemical skin conductance assessed with SUDOSCAN®. ROC AUC and cut-off values were calculated for CVT to recognize CAN based on ≥ 2 (established CAN, n = 7) or 1 (borderline CAN, n = 9) abnormal CARTs and compared to HRV indices and electrochemical skin conductance. RESULTS: Established CAN: The cut-off CVT value of 3.2LVS showed 67% sensitivity and 87% specificity (p = 0.01). Indices of HRV at either 24-hour (AUC > 0.90) and 120-hour (AUC > 0.88) performed better than CVT. Borderline CAN: The cut-off CVT value of 5.2LVS indicated 88% sensitivity and 63% specificity (p = 0.07). CVT performed better than HRV indices (AUC < 0.72). Electrochemical skin conductance (AUC:0.63-0.72) had lower sensitivity and specificity compared with CVT. CONCLUSIONS: Implementation of CVT with a clinically applicable cut-off value may be considered a quicker and accessible screening tool which could ultimately decrease the number of unrecognized CAN and initiate earlier prevention initiatives.


Subject(s)
Cardiovascular Diseases/diagnosis , Diabetes Mellitus, Type 1/complications , Diabetic Neuropathies/etiology , Vagus Nerve Stimulation/methods , Adult , Aged , Cross-Sectional Studies , Diabetes Mellitus, Type 1/physiopathology , Diabetic Neuropathies/physiopathology , Female , Humans , Male , Mass Screening , Middle Aged , Sensitivity and Specificity , Young Adult
6.
J Epidemiol Community Health ; 74(1): 7-13, 2020 01.
Article in English | MEDLINE | ID: mdl-31619458

ABSTRACT

AIM: To examine the association between socioeconomic position and the risk of atrial fibrillation (AF) in different stages of life in a population of Danish citizens. METHODS: Register-based study. We followed all individuals turning 35, 50, 65 or 80 years from 1 January 1996 to 31 December 2005 until AF, death, emigration or the end of study period (31 December 2015). Exposure was education and income. We used Cox regression for the HRs (95% CI) and the pseudo-observation method for the adjusted risk difference (RD) (%). RESULTS: A total of 2 173 857 participants were enrolled and 151 340 incident cases of AF occurred over a median of 13.6 years of follow-up. Adjusted HR (95% CI) of incident AF for the youngest age group with the highest education (ref lowest) was 0.62 (0.50 to 0.77) (women) and 0.85 (0.76 to 0.96) (men). The associations attenuated with increasing age, that is, HRs for the oldest age group were 1.04 (0.97 to 1.10) and 0.98 (0.96 to 1.04), respectively. The corresponding adjusted RDs (%) were: -0.28 (-0.43 to -0.14), -0.18 (-0.36 to -0.01), 3.04 (-0.55 to 6.64) and -0.74 (-3.38 to 2.49), respectively. Similar but weaker associations were found for income. CONCLUSION: Higher level of education and income was associated with a lower risk of being diagnosed with AF in young individuals but the association decreased with increasing age and was almost absent for the oldest age cohort. However, since AF is relatively rare in the youngest the RDs were low.


Subject(s)
Atrial Fibrillation/epidemiology , Atrial Flutter/epidemiology , Educational Status , Income , Social Class , Adult , Age Factors , Aged , Aged, 80 and over , Cohort Studies , Denmark/epidemiology , Female , Humans , Incidence , Male , Middle Aged , Risk Factors
7.
Expert Rev Cardiovasc Ther ; 16(11): 857-873, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30293472

ABSTRACT

BACKGROUND: Atrial fibrillation (AF) is a growing epidemic and evidence of a relationship to socioeconomic status (SES) is inconsistent. We aimed to summarize the literature about SES and AF and defined two objectives: (1) To examine the association between SES and the risk of AF; (2) To examine the association between SES and AF-related outcomes in an AF-population. METHODS: We performed a separate search for each objective in Ovid-MEDLINE and Ovid-Embase. For objective 1, the population included was healthy participants and outcome of interest was AF. For objective 2, the population included were patients with AF and outcome of interest was mortality, treatment, ablation for AF, knowledge about AF, and morbidity. RESULTS: For objective 1, 12 studies were included. No consistent pattern for an association between SES and the risk of AF was discovered. For objective 2, 39 studies comprising 42 outcomes were included. The majority of studies showed an association between low SES and increased mortality and morbidity. CONCLUSION: Low SES was associated with poorer outcomes when AF was present. These findings may imply that health-care professionals and policy interventions should focus on the promotion of AF-education and management among patients with AF and low SES.


Subject(s)
Atrial Fibrillation/complications , Socioeconomic Factors , Humans , Social Class
8.
Protein Eng Des Sel ; 25(3): 89-96, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22233931

ABSTRACT

CD4+ T lymphocytes play a central role in the orchestration and maintenance of the adaptive immune response. Targeting of antigen to antigen presenting cells (APCs) increases peptide loading of major histocompatibility complex (MHC) class II molecules and CD4+ T-cell activation. APCs have been targeted by APC-specific recombinant antibodies (rAbs) with single T-cell epitopes integrated in the constant region of the heavy chain (C(H)). However, the strategy may be improved if several T-cell epitopes could be delivered simultaneously by one rAb. We here demonstrate that a single rAb can be loaded with multiple identical or different T-cell epitopes, integrated as loops between ß-strands in C(H) domains. One epitope was inserted in C(H)1, while two were placed in C(H)2 of IgG. T-cell proliferation assays showed that all three peptides were excised from loops and presented on MHC class II to T-cells. Induction of T-cell activation by each epitope in the multi-peptide rAb was as good, or even better, than that elicited by corresponding single-peptide rAbs. Furthermore, following DNA vaccination of mice with plasmids that encode CD40-specific rAbs loaded with either one or three peptides, T-cell responses were induced. Thus, integration of multiple epitopes in C(H) region loops of APC-specific rAbs is feasible and may be utilized in design of multi-vaccines.


Subject(s)
Antigen-Presenting Cells/immunology , CD4-Positive T-Lymphocytes/immunology , CD40 Antigens/immunology , Epitopes/immunology , Genes, Immunoglobulin , Immunoglobulin Constant Regions/immunology , Immunoglobulin Heavy Chains/genetics , Animals , Antigen Presentation , Genetic Vectors , Histocompatibility Antigens Class II/immunology , Humans , Immunoglobulin Constant Regions/genetics , Lymphocyte Activation , Mice , Mice, Inbred BALB C , Mice, Inbred C3H , Mice, Transgenic , Models, Molecular , Plasmids , Protein Conformation , Protein Engineering , Protein Structure, Tertiary , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/immunology , T-Cell Antigen Receptor Specificity , Vaccination , Vaccines, DNA
9.
BMC Biotechnol ; 10: 61, 2010 Aug 24.
Article in English | MEDLINE | ID: mdl-20735812

ABSTRACT

BACKGROUND: Whereas T cell receptors (TCRs) detect peptide/major histocompatibility complexes (pMHCs) with exquisite specificity, there are challenges regarding their expression and use as soluble detection molecules due to molecular instability. We have investigated strategies for the production of TCR-immunoglobulin (Ig) fusion proteins. Two different TCRs that are characteristic of a mouse model for idiotype (Id) dependent immune regulation were engineered. They are structurally unrelated with different variable (V), diversity (D) and joining (J) segments, but each share one V gene segment, either Vα or Vß, with the well characterized murine TCR, 2C. RESULTS: Several TCR-Ig formats were assessed. In one, the TCR V domains were fused to Ig constant (C) regions. In others, the complete extracellular part of the TCR was fused either to a complete Ig or an Ig Fc region. All molecules were initially poorly secreted from eukaryotic cells, but replacement of unfavourable amino acids in the V regions improved secretion, as did the introduction of a disulfide bridge between the TCR C domains and the removal of an unpaired cysteine. A screening strategy for selection of mutations that stabilize the actual fusion molecules was developed and used successfully. Molecules that included the complete heterodimeric TCR, with a stabilizing disulfide bridge, were correctly folded as they bound TCR-specific antibodies (Abs) and detected pMHC on cells after specific peptide loading. CONCLUSIONS: We show that fully functional TCR-Ig fusion proteins can be made in good yields following stabilizing engineering of TCR V and C region genes. This is important since TCR-Ig fusions will be important probes for the presence of specific pMHCs in vitro and in vivo. In the absence of further affinity maturation, the reagents will be very useful for the detection of kinetic stability of complexes of peptide and MHC.


Subject(s)
Immunoglobulins/genetics , Protein Engineering/methods , Receptors, Antigen, T-Cell/genetics , Animals , Cell Line , Humans , Insecta/cytology , Mutagenesis, Site-Directed , Mutation , Protein Folding , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/metabolism , Transfection
10.
BMC Biotechnol ; 10: 8, 2010 Feb 03.
Article in English | MEDLINE | ID: mdl-20128915

ABSTRACT

BACKGROUND: Efficient expression systems exist for antibody (Ab) molecules, which allow for characterization of large numbers of individual Ab variants. In contrast, such expression systems have been lacking for soluble T cell receptors (TCRs). Attempts to generate bacterial systems have generally resulted in low yields and material which is prone to aggregation and proteolysis. Here we present an optimized periplasmic bacterial expression system for soluble single chain (sc) TCRs. RESULTS: The effect of 1) over-expression of the periplasmic chaperon FkpA, 2) culture conditions and 3) molecular design was investigated. Elevated levels of FkpA allowed periplasmic soluble scTCR expression, presumably by preventing premature aggregation and inclusion body formation. Periplasmic expression enables disulphide bond formation, which is a prerequisite for the scTCR to reach its correct fold. It also enables quick and easy recovery of correctly folded protein without the need for time-consuming downstream processing. Expression without IPTG induction further improved the periplasmic expression yield, while addition of sucrose to the growth medium showed little effect. Shaker flask yield of mg levels of active purified material was obtained. The Valphabeta domain orientation was far superior to the Vbetaalpha domain orientation regarding monomeric yield of functionally folded molecules. CONCLUSION: The general expression regime presented here allows for rapid production of soluble scTCRs and is applicable for 1) high yield recovery sufficient for biophysical characterization and 2) high throughput screening of such molecules following molecular engineering.


Subject(s)
Escherichia coli Proteins/metabolism , Membrane Proteins/metabolism , Molecular Chaperones/metabolism , Peptidylprolyl Isomerase/metabolism , Periplasm/metabolism , Receptors, Antigen, T-Cell/biosynthesis , Escherichia coli/genetics , Escherichia coli/metabolism , Genetic Vectors , Protein Folding , Protein Structure, Secondary , Receptors, Antigen, T-Cell/genetics , Receptors, Antigen, T-Cell/isolation & purification
11.
Immunol Cell Biol ; 88(5): 515-22, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20066000

ABSTRACT

The V region antigenic determinants (idiotopes (Ids)) of antibodies (Abs) have been suggested to be involved in regulating the immune system. Certain diseases such as diabetes mellitus have recently been associated with a disequilibrium between Id(+) and anti-Id Abs. However, it is unknown how Abs carrying complementary idiotypes (that is, Id(+) and anti-Id Abs) regulate each other at the level of B and T cells. In this study, we show that B lymphoma cells genetically equipped with anti-Id BCR V regions receive a signal when exposed to Id(+)Ig. Moreover, they become x 10(4) more efficient at presenting exogenous Id(+) Ab to CD4(+) T cells in vitro. Activated Id-specific T cells in turn regulated the Id-specific B lymphoma cells. Similar results were obtained in vivo in a surrogate model in which an Id-peptide was incorporated genetically into the C-region of a recombinant Ab that targeted IgD on B cells. The findings suggest that conventional T-B collaboration can explain communication between complementary Id(+) and anti-Id Ab at the cellular level. A model is suggested that integrates present and previous data on B-cell regulation by Id-specific T cells.


Subject(s)
Antibodies, Anti-Idiotypic/immunology , B-Lymphocytes/immunology , Cell Communication/immunology , Immunoglobulin Idiotypes/immunology , T-Lymphocytes/immunology , Animals , Antigen Presentation/immunology , Blotting, Western , Cell Separation , Enzyme-Linked Immunosorbent Assay , Flow Cytometry , Immunoprecipitation , Lymphocyte Activation/immunology , Mice , Mice, Inbred BALB C , Mice, Transgenic , Receptors, Antigen, T-Cell/genetics , Receptors, Antigen, T-Cell/immunology , Transfection
12.
J Immunol ; 181(10): 7062-72, 2008 Nov 15.
Article in English | MEDLINE | ID: mdl-18981126

ABSTRACT

Targeting of T cell epitopes to APC enhances T cell responses. We used an APC-specific Ab (anti-IgD) and substituted either of 18 loops connecting beta strands in human IgG constant H (C(H)) domains with a characterized T cell peptide epitope. All Ab-epitope fusion molecules were secreted from producing cells except IgG-loop 2(BC)C(H)1, and comparing levels, a hierarchy appeared with fusions involving C(H)2 > or = C(H)1 > C(H)3. Within each domain, fusion at loop 6(FG) showed best secretion, while low secretion correlated with the substitution of native loops that contain conserved amino acids buried within the folded molecule. Comparing the APC-specific rAb molecules for their ability to induce T cell activation in vitro, the six mutants with epitope in C(H)2 were the most effective, with loop 4C(H)2 ranking on top. The C(H)1 mutants were more resistant to processing, and the loop 6C(H)1 mutant only induced detectable activation. The efficiency of the C(H)3 mutants varied, with loop 6C(H)3 being the least effective and equal to loop 6 C(H)1. Considering both rAb secretion level and T cell activation efficiency, a total of eight loops may carry T cell epitopes to APC for processing and presentation to T cells, namely, all in C(H)2 in addition to loop 6 in C(H)1 and C(H)3. Comparing loop 4C(H)2 with loop 6C(H)1 mutants after injection of Ab in BALB/c mice, the former was by far the most efficient and induced specific T cell activation at concentrations at least 100-fold lower than loop 6C(H)1.


Subject(s)
Antigen Presentation/immunology , Epitopes, T-Lymphocyte/immunology , Histocompatibility Antigens Class II/immunology , Immunoglobulin Constant Regions/immunology , Immunoglobulin G/immunology , Lymphocyte Activation/immunology , Animals , Blotting, Western , Enzyme-Linked Immunosorbent Assay , Humans , Immunoglobulin Constant Regions/chemistry , Immunoglobulin G/chemistry , Mice , Mice, Inbred BALB C , Protein Structure, Secondary , Recombinant Fusion Proteins/chemical synthesis , Recombinant Fusion Proteins/chemistry , Recombinant Fusion Proteins/immunology
13.
Eur J Immunol ; 35(11): 3142-52, 2005 Nov.
Article in English | MEDLINE | ID: mdl-16184515

ABSTRACT

In order to prevent or ameliorate autoimmune disease, it would be desirable to induce central tolerance to peripheral self-antigens. We have investigated whether recombinant antibodies (Ab) that deliver T cell epitopes to antigen-presenting cells (APC) in the thymus can be used to induce thymocyte deletion. Troybodies are recombinant Ab with V regions specific for APC surface molecules that have T cell epitopes genetically introduced in their C domains. When MHC class II-specific Troybodies with the lambda2(315)T cell epitope were injected into lambda2(315)-specific TCR transgenic mice, a profound deletion of (CD4+)8+ thymocytes was observed. MHC class II-specific Troybodies were 10-100-fold more efficient than non-targeting peptide Ab, and 500-fold more efficient than synthetic peptide at inducing deletion. Similar findings were observed when MHC class II-specific Troybodies with the OVA(323-339) T cell epitope were injected into OVA-specific TCR transgenic mice. Although deletion was transient after a single injection, newborn mice repeatedly injected with MHC class II-specific Troybodies for 4 weeks, had reduced antigen-specific T cells in peripheral lymphoid tissues and reduced T cell responses. These experiments suggest that Troybodies constructed to target specifically thymic APC could be useful tools for induction and maintenance of central T cell tolerance in autoimmune diseases.


Subject(s)
Antibodies , Clonal Deletion/immunology , Epitopes, T-Lymphocyte/biosynthesis , Immune Tolerance , Peptides/metabolism , Thymus Gland/metabolism , Animals , Antibodies/genetics , Antibodies/metabolism , Antigen Presentation/genetics , CD4 Antigens/metabolism , CD8 Antigens/metabolism , Histocompatibility Antigens Class II/immunology , Immune Tolerance/genetics , Lymphocyte Count , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, SCID , Mice, Transgenic , Ovalbumin/metabolism , Peptide Fragments/metabolism , Peptides/immunology , Receptors, Antigen, T-Cell/genetics , Receptors, Fc/immunology , Recombinant Proteins , T-Lymphocytes/immunology , Thymus Gland/immunology
14.
J Immunol Methods ; 298(1-2): 93-104, 2005 Mar.
Article in English | MEDLINE | ID: mdl-15847800

ABSTRACT

In studies of the relation between structure and function of proteins of the immune system, there is a continuous need for screening of a large number of protein variants. To optimise the yield following transient gene expression in small or medium culture volumes, several parameters were investigated. First, secretion levels of a soluble form of human Fcgamma receptor IIA (FcgammaRIIA) were measured after transfection of 293, 293E, 293T as well as COS-7 cell lines. The transgene was under cytomegalovirus (CMV) promoter control on the expression vector pcDNA3, which also contains an SV40 origin of replication (SV40 ori). All 293 cell lines secreted more protein than COS-7 cells. Introduction of the Epstein Barr virus (EBV) origin of replication (oriP) greatly increased the protein expression from the 293E cells, both the amount of protein produced per day and the duration of production. At best, 293E cells secreted fully functional protein for 3-4 weeks provided supernatant was harvested every 2-3 days followed by medium replacement. This method was then used for expression of soluble forms of human FcgammaRI, FcgammaRIIB, the human neonatal Fc receptor (FcRn), a T cell receptor (TCR)-immunoglobulin (Ig) fusion protein, and human IgG3. With an initial culture volume of 5 ml, the yield was approximately 200 microg for FcgammaRIIA, 1.5 microg for FcgammaRI, 5 microg for FcRn, 20 microg for FcgammaRIIB, 40 microg for the TCR-Ig fusion protein and 850 microg for IgG3. Culture expansion during the 3 weeks of culture further increased the yield. Protein yield was also improved by scaling up the initial volume. This approach can provide sufficient amounts of protein for screening experiments, and in the case of antibody, milligrams of recombinant protein for extensive structural analysis can be obtained from one single transient transfection. The approach should be of interest to laboratories that do not have access to a bioreactor but still have a requirement for reasonable amounts of protein to be produced in an easy and cost-effective manner.


Subject(s)
Genetic Techniques , Immunoglobulin G/biosynthesis , Receptors, Antigen, T-Cell/biosynthesis , Receptors, Fc/biosynthesis , Recombinant Fusion Proteins/biosynthesis , Animals , Antigens, Polyomavirus Transforming , COS Cells , Cell Culture Techniques/methods , Chlorocebus aethiops , Cytomegalovirus/genetics , Epstein-Barr Virus Nuclear Antigens/genetics , Genetic Vectors , Humans , Promoter Regions, Genetic , Transfection , Transgenes
15.
Mol Ther ; 9(3): 328-36, 2004 Mar.
Article in English | MEDLINE | ID: mdl-15006599

ABSTRACT

Antibodies are useful for the treatment of a variety of diseases. We here demonstrate that mouse muscle produced monoclonal antibodies (mAb) after a single injection of immunoglobulin genes as plasmid DNA. In vivo electroporation of muscle greatly enhanced antibody production. For chimeric antibodies, levels of 50-200 ng mAb/ml serum were obtained but levels declined after 7-14 days due to an immune response against the xenogeneic parts of the antibody. By contrast, fully mouse antibodies persisted in serum for at least 7 months. mAb produced by the muscle had correct structure, specificity, and biological effector functions. The findings were extended to a larger animal, the sheep, in which mAb serum levels of 30-50 ng/ml were obtained. Sustained levels of serum mAb, induced by single injection of Ig genes and electroporation of muscle cells, may offer significant advantages in the treatment of human diseases.


Subject(s)
Antibodies, Monoclonal/metabolism , Electroporation/methods , Gene Transfer Techniques , Genetic Therapy/methods , Genetic Vectors , Muscles/metabolism , Plasmids/metabolism , Animals , Antibodies, Monoclonal/chemistry , Antibodies, Monoclonal/genetics , Complement Activation , Complement System Proteins , DNA/metabolism , Dose-Response Relationship, Immunologic , Enzyme-Linked Immunosorbent Assay , Flow Cytometry , Immunoblotting , Immunoglobulins/metabolism , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Sheep , Spleen/metabolism , Time Factors
16.
J Immunol ; 168(5): 2154-62, 2002 Mar 01.
Article in English | MEDLINE | ID: mdl-11859101

ABSTRACT

A major objective in vaccine development is the design of reagents that give strong, specific T cell responses. We have constructed a series of rAb with specificity for MHC class II (I-E). Each has one of four different class II-restricted T cell epitopes genetically introduced into the first C domain of the H chain. These four epitopes are: 91-101 lambda2(315), which is presented by I-E(d); 110-120 hemagglutinin (I-E(d)); 323-339 OVA (I-A(d)); and 46-61 hen egg lysozyme (I-A(k)). We denote such APC-specific, epitope-containing Ab "Troybodies." When mixed with APC, all four class II-specific Troybodies were approximately 1,000 times more efficient at inducing specific T cell activation in vitro compared with nontargeting peptide Ab. Furthermore, they were 1,000-10,000 times more efficient than synthetic peptide or native protein. Conventional intracellular processing of the Troybodies was required to load the epitopes onto MHC class II. Different types of professional APC, such as purified B cells, dendritic cells, and macrophages, were equally efficient at processing and presenting the Troybodies. In vivo, class II-specific Troybodies were at least 100 times more efficient at targeting APC and activating TCR-transgenic T cells than were the nontargeting peptide Ab. Furthermore, they were 100-100,000 times more efficient than synthetic peptide or native protein. The study shows that class II-specific Troybodies can deliver a variety of T cell epitopes to professional APC for efficient presentation, in vitro as well as in vivo. Thus, Troybodies may be useful as tools in vaccine development.


Subject(s)
Antibodies, Monoclonal/immunology , Antigen Presentation , Antigen-Presenting Cells/immunology , Epitopes, T-Lymphocyte/immunology , Histocompatibility Antigens Class II/immunology , Animals , Antibodies, Monoclonal/genetics , B-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/immunology , Cell Line , Cells, Cultured , DNA-Binding Proteins/genetics , Dendritic Cells/immunology , Epitopes, T-Lymphocyte/genetics , Genes, T-Cell Receptor , Lymphocyte Activation , Macrophages/immunology , Mice , Mice, Inbred BALB C , Mice, Knockout , Mice, Transgenic , Recombinant Fusion Proteins/metabolism
SELECTION OF CITATIONS
SEARCH DETAIL
...