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1.
J Appl Gerontol ; 43(4): 349-362, 2024 Apr.
Article in English | MEDLINE | ID: mdl-37984553

ABSTRACT

As the family usually plays a central role at the end of life, the quality of family relationships may influence how individuals approach advance care planning (ACP). Our study investigates the associations of trust in relatives with regard to end-of-life (EOL) issues-used as a proxy measure of family relationship quality-with individuals' engagement in EOL discussions, advance directive (AD) awareness, approval and completion, and designation of a healthcare proxy. Using nationally representative data of adults aged 55 years and over from wave 6 (2015) of the Survey of Health, Ageing, and Retirement in Europe (SHARE) in Switzerland (n = 1911), we show that complete trust in relatives is related to higher engagement in ACP. Subject to patient consent, the family should, therefore, be included in the ACP process, as such practice could enhance patient-centered EOL care and quality of life at the end of life.


Subject(s)
Advance Care Planning , Terminal Care , Humans , Trust , Quality of Life , Death
2.
J Mycol Med ; 27(4): 449-456, 2017 Dec.
Article in French | MEDLINE | ID: mdl-29132793

ABSTRACT

The increase use of immunosuppressive treatments in patients with solid cancer and/or inflammatory diseases requires revisiting our practices for the prevention of infectious risk in the care setting. A review of the literature by a multidisciplinary working group at the beginning of 2014 wished to answer the following 4 questions to improve healthcare immunocompromised patients: (I) How can we define immunocompromised patients with high, intermediate and low infectious risk, (II) which air treatment should be recommended for this specific population? (III) What additional precautions should be recommended for immunocompromised patients at risk for infection? (IV) Which global environmental control should be recommended? Based on data from the literature and using the GRADE method, we propose 15 recommendations that could help to reduce the risk of infection in these exposed populations.


Subject(s)
Immunocompromised Host , Infection Control , Infections , Air Microbiology , Disease Susceptibility , France , Humans , Practice Guidelines as Topic , Risk Factors
3.
J Dent Educ ; 81(3): 287-292, 2017 Mar.
Article in English | MEDLINE | ID: mdl-28250034

ABSTRACT

As universities and colleges seek to reach more students in efficient ways, the use of synchronous distance education (SDE) can be an alternative to traditional classrooms. This study focused on face-to-face SDE, in which classrooms equipped with interactive synchronous technologies allow students in both classrooms and the professor to synchronously see and hear one another. The aims of the study were to aid educators in understanding student concerns, determine whether face-to face SDE was sacrificing overall student satisfaction, and investigate whether satisfaction improved as the program matured. This mixed-methods study utilized a convenience sample of two cohorts of dental hygiene students (n=122) in one program: Cohort 1, which graduated in 2014 as the first class to experience face-to-face SDE; and Cohort 2, which graduated in 2015. The response rate for the two cohorts was 95%. Perceptions of face-to-face SDE versus traditional classroom experiences and characteristics of face-to-face SDE were measured using pre- and post-program surveys. The results showed no difference in student perceptions and expectations pre-course vs. post-course, although Cohort 2 had a more positive perception of SDE than did Cohort 1 (p<0.001). Perceptions of characteristics related to the classroom setting and instructor satisfaction were overall positive (p<0.001). The qualitative data suggested that technological support and faculty familiarity with SDE were substantial influences on students' satisfaction. Overall, there was no significant difference in satisfaction with face-to-face SDE when students compared it to their previous classroom experiences.


Subject(s)
Dental Hygienists/education , Education, Distance , Personal Satisfaction , Students, Dental/psychology , Adult , Education, Distance/methods , Female , Humans , Male , Program Evaluation , United States , Young Adult
4.
Emerg Infect Dis ; 20(2): 211-6, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24447466

ABSTRACT

In 2012, a female wildlife biologist experienced fever, malaise, headache, generalized myalgia and arthralgia, neck stiffness, and a sore throat shortly after returning to the United States from a 6-week field expedition to South Sudan and Uganda. She was hospitalized, after which a maculopapular rash developed and became confluent. When the patient was discharged from the hospital on day 14, arthralgia and myalgia had improved, oropharynx ulcerations had healed, the rash had resolved without desquamation, and blood counts and hepatic enzyme levels were returning to reference levels. After several known suspect pathogens were ruled out as the cause of her illness, deep sequencing and metagenomics analysis revealed a novel paramyxovirus related to rubula-like viruses isolated from fruit bats.


Subject(s)
Chiroptera/virology , Paramyxoviridae Infections/virology , Paramyxovirinae/classification , RNA, Viral/classification , Acute Disease , Adult , Animals , Female , High-Throughput Nucleotide Sequencing , Humans , Molecular Sequence Annotation , Paramyxoviridae Infections/pathology , Paramyxoviridae Infections/transmission , Paramyxovirinae/genetics , Paramyxovirinae/isolation & purification , Phylogeny , RNA, Viral/genetics , Sudan , Travel , Uganda
6.
BMC Gastroenterol ; 10: 82, 2010 Jul 16.
Article in English | MEDLINE | ID: mdl-20637112

ABSTRACT

BACKGROUND: We have previously found that TLR4-deficient (TLR4-/-) mice demonstrate decreased expression of mucosal PGE 2 and are protected against colitis-associated neoplasia. However, it is still unclear whether PGE 2 is the central factor downstream of TLR4 signaling that promotes intestinal tumorigenesis. To further elucidate critical downstream pathways involving TLR4-mediated intestinal tumorigenesis, we examined the effects of exogenously administered PGE 2 in TLR4-/- mice to see if PGE 2 bypasses the protection from colitis-associated tumorigenesis. METHOD: Mouse colitis-associated neoplasia was induced by azoxymethane (AOM) injection followed by two cycles of dextran sodium sulfate (DSS) treatment. Two different doses of PGE 2 (high dose group, 200 microg, n = 8; and low dose group, 100 microg, n = 6) were administered daily during recovery period of colitis by gavage feeding. Another group was given PGE 2 during DSS treatment (200 microg, n = 5). Inflammation and dysplasia were assessed histologically. Mucosal Cox-2 and amphiregulin (AR) expression, prostanoid synthesis, and EGFR activation were analyzed. RESULTS: In control mice treated with PBS, the average number of tumors was greater in WT mice (n = 13) than in TLR4-/- mice (n = 7). High dose but not low dose PGE 2 treatment caused an increase in epithelial proliferation. 28.6% of PBS-treated TLR4-/- mice developed dysplasia (tumors/animal: 0.4 +/- 0.2). By contrast, 75.0% (tumors/animal: 1.5 +/- 1.2, P < 0.05) of the high dose group and 33.3% (tumors/animal: 0.3 +/- 0.5) of the low dose group developed dysplasia in TLR4-/- mice. Tumor size was also increased by high dose PGE 2 treatment. Endogenous prostanoid synthesis was differentially affected by PGE 2 treatment during acute and recovery phases of colitis. Exogenous administration of PGE 2 increased colitis-associated tumorigenesis but this only occurred during the recovery phase. Lastly, PGE 2 treatment increased mucosal expression of AR and Cox-2, thus inducing EGFR activation and forming a positive feedback mechanism to amplify mucosal Cox-2. CONCLUSIONS: These results highlight the importance of PGE 2 as a central downstream molecule involving TLR4-mediated intestinal tumorigenesis.


Subject(s)
Colitis/physiopathology , Colonic Neoplasms/physiopathology , Dinoprostone/physiology , Toll-Like Receptor 4/physiology , Amphiregulin , Animals , Azoxymethane/adverse effects , Cell Proliferation/drug effects , Colitis/chemically induced , Colonic Neoplasms/chemically induced , Cyclooxygenase 2/physiology , Dextran Sulfate/adverse effects , Dinoprostone/pharmacology , Disease Models, Animal , Dose-Response Relationship, Drug , EGF Family of Proteins , ErbB Receptors/physiology , Female , Glycoproteins/physiology , Intercellular Signaling Peptides and Proteins/physiology , Intestinal Mucosa/drug effects , Intestinal Mucosa/pathology , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Prostaglandins/physiology , Signal Transduction/physiology , Toll-Like Receptor 4/genetics
7.
Lab Invest ; 90(9): 1295-305, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20498653

ABSTRACT

Epiregulin (EPI) and amphiregulin (AR) are epidermal growth factor receptor (EGFR) ligands implicated in mucosal repair and tumorigenesis. We have shown that Toll-like receptor 4 (TLR4) induces intestinal epithelial cell (IEC) proliferation by activating EGFR through AR expression. We examined whether TLR4 differentially regulates expression of EGFR ligands in response to mucosal injury. The human IEC line SW480 was examined expression of EGFR ligands, EGFR phosphorylation, and proliferation in response to lipopolysaccharide (LPS). Small-interfering RNA (siRNA) was used to block TLR4. Neutralizing antibodies to EGFR ligands were used to examine inhibition of LPS-dependent EGFR activation. Acute colitis and recovery were examined in the mice given 2.5% dextran sodium sulfate (DSS). Colonic secretion of EPI and AR was analyzed by enzyme-linked immunosorbent assay. LPS selectively induces EPI and AR but not other EGFR ligands. LPS induced early EPI mRNA expression between 30 min and 24 h. The neutralizing antibodies to EPI and AR prevented activation of EGFR by LPS. LPS induces IEC proliferation (200%, P=0.01) in 24 h but blocking EPI and AR significantly decreased proliferation. In vivo, mucosal EPI and AR expression are significantly decreased in TLR4(-/-) mice (P=0.02) compared to wild-type mice during acute colitis. EPI and AR exhibit different kinetics in response to mucosal damage: EPI expression is upregulated acutely at day 7 of DSS, but falls during recovery at day 14. By contrast, a sustained upregulation of AR expression is seen during mucosal injury and repair. We show that TLR4 regulates EPI and AR expression and that both these EGFR ligands are necessary for optimal proliferation of IEC. The diverse kinetics of EPI and AR expression suggest that they function in distinct roles with respect to acute injury vs repair. Our results highlight the role of bacterial sensing for IEC homeostasis and may lead to targeted therapy for mucosal healing and prevention of tumorigenesis.


Subject(s)
Epidermal Growth Factor/genetics , Epidermal Growth Factor/metabolism , Toll-Like Receptor 4/immunology , Toll-Like Receptor 4/metabolism , Amphiregulin , Animals , Antibodies, Neutralizing , Cell Line , Cell Proliferation/drug effects , Colitis/genetics , Colitis/immunology , Colitis/metabolism , Dextran Sulfate/immunology , Dextran Sulfate/metabolism , Dextran Sulfate/pharmacology , EGF Family of Proteins , Enzyme-Linked Immunosorbent Assay , Epidermal Growth Factor/immunology , Epiregulin , Epithelial Cells/immunology , Epithelial Cells/metabolism , ErbB Receptors/genetics , ErbB Receptors/immunology , ErbB Receptors/metabolism , Glycoproteins , Humans , Intercellular Signaling Peptides and Proteins , Lipopolysaccharides/immunology , Lipopolysaccharides/metabolism , Mice , Mice, Knockout , Mucous Membrane/metabolism , Toll-Like Receptor 4/genetics , Up-Regulation/drug effects
8.
Article in English | MEDLINE | ID: mdl-20690468

ABSTRACT

PURPOSE: The purpose of this case study is to extend the understanding of leadership development in healthcare by documenting the impact of a systemic approach to developing frontline leaders in a large Canadian healthcare organization. DESIGN/METHODOLOGY/APPROACH: A total of 92 participants working in acute and community settings participated in an eight-day certificate program that combined classroom instruction, practical skill development, and applied projects. Program content was based on a learning needs assessment conducted with potential participants and their supervisors. FINDINGS: Frontline leaders and their supervisors rated the program positively in terms of its impact on participants' confidence and willingness to lead, awareness of leadership opportunities, communication, problem solving, response to conflict, and the ability to support their teams through change. It was also found, however, that supervisors' ratings were generally lower than those of participants. PRACTICAL IMPLICATIONS: Systemic approaches to leadership development offer healthcare the best chance of addressing the current leadership crisis. The challenge is finding innovative ways to demonstrate sustainable benefits in an industry that is struggling to address cost pressures. In the present study, personal and supervisor evaluations were used in conjunction with completion of applied change projects to demonstrate a tangible return on investment. ORIGINALITY/VALUE: Leadership can be learned and there is no better point of entry for development than those in frontline leadership positions. However, developing future leaders requires the commitment of an entire leadership community. Healthcare organizations that are experiencing leadership gaps must be prepared to make a long term investment if they want to achieve lasting healthcare reforms.


Subject(s)
Health Personnel , Leadership , Staff Development , Canada , Community Health Services , Humans
9.
Environ Sci Technol ; 36(22): 4811-7, 2002 Nov 15.
Article in English | MEDLINE | ID: mdl-12487304

ABSTRACT

It has previously been demonstrated that [14C]-labeled polycyclic aromatic hydrocarbons (PAHs) can be oxidized to 14CO2 in anoxic, PAH-contaminated, marine harbor sediments in which sulfate reduction is the terminal electron-accepting process. However, it has not previously been determined whether this degradation of [14C]-PAHs accurately reflects the degradation of the in situ pools of contaminant PAHs. In coal tar-contaminated sediments from Boston Harbor, [14C]-naphthalene was readily oxidized to 14CO2, but, after 95 d of incubation under anaerobic conditions, there was no significant decrease in the detectable pool of in situ naphthalene in these sediments. Therefore, to better evaluate the anaerobic biodegradation of the in situ PAH pools, the concentrations of these contaminants were monitored for ca. 1 year during which the sediments were incubated under conditions that mimicked those found in situ. There was loss of all of the PAHs that were monitored (2-5 ring congeners), including high molecular weight PAHs, such as benzo[a]pyrene, that have not previously been shown to be degraded under anaerobic conditions. There was no significant change in the PAH levels in the sediments amended with molybdate to inhibit sulfate-reducing bacteria or in sediments in which all microorganisms had been killed with glutaraldehyde. In some instances, over half of the detectable pools of in situ 2-3 ring PAHs were degraded. In general, the smaller PAHs were degraded more rapidly than the larger PAHs. A distinct exception in the Boston Harbor sediment was naphthalene which was degraded very slowly at a rate comparable to the larger PAHs. In a similar in situ-like study of fuel-contaminated sediments from Liepaja Harbor, Latvia, there was no decline in PAH levels in samples that were sulfate-depleted. However, when the Latvia sediments were supplemented with sufficient sodium sulfate or gypsum to elevate pore water levels of sulfate to approximately 14-25 mM there was a 90% decline in the naphthalene and a 60% decline in the 2-methylnaphthalene pool within 90 days. These studies demonstrate for the first time that degradation by anaerobic microorganisms can significantly impact the in situ pools of PAHs in petroleum-contaminated, anoxic, sulfate-reducing harbor sediments and suggest that the self-purification capacity of contaminated harbor sediments is greater than previously considered.


Subject(s)
Bacteria, Anaerobic/physiology , Geologic Sediments/chemistry , Geologic Sediments/microbiology , Petroleum , Polycyclic Aromatic Hydrocarbons/metabolism , Sulfur-Reducing Bacteria/physiology , Water Pollutants, Chemical/metabolism , Biodegradation, Environmental , Environmental Monitoring , Molecular Weight , Ships , Transportation
10.
J Clin Invest ; 100(10): 2538-46, 1997 Nov 15.
Article in English | MEDLINE | ID: mdl-9366568

ABSTRACT

The F4 idiotype is a heavy chain determinant expressed almost exclusively on IgG immunoglobulins and is highly associated with specificity for double-stranded DNA. Since high-titered F4 expression is present predominantly in sera of patients with systemic lupus erythematosus (SLE), we thought F4+ IgG antibodies might constitute a useful subset of immunoglobulins in which to investigate lupus-specific alterations in variable (V) region gene expression or in the process of somatic mutation. This molecular analysis of F4+ B cell lines generated from lupus patients demonstrates that despite the strong association of F4 reactivity with specificity for native DNA, there is no apparent VH gene restriction. Furthermore, VH gene segments encoding these antibodies are also used in protective immune responses. An examination of the process of somatic mutation in F4+ antibodies showed no abnormality in frequency of somatic mutation nor in the distribution of mutations in complementarity-determining regions or framework regions. However, there was a decrease in targeting of mutations to putative mutational hot spots. This subtle difference in mutations present in these antibodies may reflect an intrinsic defect in mutational machinery or, more likely, altered state of B cell activation that affects the mutational process and perhaps also negative selection.


Subject(s)
Antibodies, Antinuclear/genetics , Immunoglobulin G/genetics , Immunoglobulin Isotypes/genetics , Immunoglobulin Variable Region/genetics , Lupus Erythematosus, Systemic/genetics , Point Mutation , Amino Acid Sequence , Antibodies, Bacterial/immunology , Antigens, Viral/immunology , Base Sequence , Cell Line, Transformed , Gene Rearrangement , Herpesvirus 4, Human , Humans , Immunoglobulin Heavy Chains/genetics , Immunoglobulin Light Chains/genetics , Lupus Erythematosus, Systemic/immunology , Molecular Sequence Data , Polymerase Chain Reaction , Reference Values
11.
Methods ; 11(1): 70-8, 1997 Jan.
Article in English | MEDLINE | ID: mdl-8990091

ABSTRACT

Studies of anti-double-stranded (anti-ds)DNA antibodies have provided insights into how and why these antibodies arise in systemic lupus erythematosus. In this review we discuss the experimental approaches that have been used by our laboratory to study these autoantibodies. Structure/function analyses including site-directed mutagenesis have helped characterize the molecular genetics of anti-dsDNA antibodies, and more recently peptide libraries have been used to define molecular motifs that these antibodies bind. Most of the pathogenic anti-dsDNA antibodies observed in lupus are somatically mutated. We demonstrated in vitro and in vivo that anti-bacterial antibodies can mutate to acquire specificity for dsDNA. Furthermore, using a fusion partner constitutively expressing bcl-2, NSO(bcl-2), we have shown the existence of anergic or preapoptotic B cells making antibodies that cross-react with both bacterial antigen and dsDNA. Whether defects in the regulation of these antibodies might contribute to serum expression of anti-dsDNA antibodies in some individuals remains unknown. A major emphasis of this review is the regulation of anti-dsDNA antibodies in a transgenic mouse model harboring the gene for the heavy chain of a pathogenic anti-dsDNA antibody. Nonautoimmune transgenic mice effectively regulate autoreactive B cells by anergy and deletion, while their autoimmune counterparts do not. The vast majority of anergic B cells expressing high-affinity transgenic anti-dsDNA antibody fail to display allelic exclusion of the heavy chain. We postulate that this may be one mechanism that allows them to escape deletion. Comparative studies on light chain usage in both the autoimmune and the nonautoimmune transgenic mouse strains have demonstrated that within the autoreactive B-cell population, there are subsets that are differentially regulated. Ultimately transgenic animals making pathogenic autoantibodies may provide us with a system for testing novel therapies for autoimmune disease.


Subject(s)
Antibodies, Antinuclear/immunology , DNA/immunology , Animals , Antibodies, Antinuclear/chemistry , Antibodies, Antinuclear/metabolism , Autoimmune Diseases/immunology , Autoimmune Diseases/therapy , B-Lymphocytes/immunology , Humans , Hybridomas/immunology , Hybridomas/metabolism , Immunoglobulin Idiotypes/immunology , Lupus Erythematosus, Systemic/immunology , Lupus Erythematosus, Systemic/therapy , Mice , Mice, Transgenic , Mutation/genetics , Peptides/immunology , Peptides/metabolism
12.
Ann N Y Acad Sci ; 764: 301-11, 1995 Sep 29.
Article in English | MEDLINE | ID: mdl-7486540

ABSTRACT

Our previous studies of anti-DNA antibodies in SLE have demonstrated a preferential use of V kappa I and V lambda II gene families to encode light chains of antibodies that express the anti-DNA-associated 3I and 8.12 idiotypes, respectively. In this study, we employed PCR to obtain V kappa I and V lambda II germline genes from lupus patients in order to compare the germline genes to genes encoding expressed V kappa I and V lambda II light chains and to analyze the extent of somatic mutation among autoantibodies that derive from these light chain families. Our analysis shows that the germline repertoire among all persons (autoimmune and healthy) is comparable and that somatic mutation is used to diversify autoantibodies as well as anti-microbial antibodies. We have observed that autoantibodies encoded by V kappa I and V lambda II genes have a higher number of amino acid replacements in CDRs than autoantibodies encoded by other VL gene families. In addition, there may be subtle differences in V gene usage that distinguish the V kappa I-encoded light chains from other expressed V kappa light chains.


Subject(s)
Antibodies, Antinuclear/genetics , Autoimmune Diseases/immunology , B-Lymphocytes/immunology , Gene Rearrangement, B-Lymphocyte, Light Chain , Genes, Immunoglobulin , Immunoglobulin Variable Region/genetics , Immunoglobulin kappa-Chains/genetics , Immunoglobulin lambda-Chains/genetics , Lupus Erythematosus, Systemic/immunology , Point Mutation , Autoimmune Diseases/genetics , Base Sequence , Gene Library , Humans , Immunoglobulin Idiotypes/genetics , Immunoglobulin Idiotypes/immunology , Lupus Erythematosus, Systemic/genetics , Molecular Sequence Data , Polymerase Chain Reaction
13.
Autoimmunity ; 20(4): 259-65, 1995.
Article in English | MEDLINE | ID: mdl-7578888

ABSTRACT

Our studies of anti-DNA antibodies in systemic lupus erythematosus have demonstrated a preferential use of the V kappa I family to encode light chains of antibodies that express the anti-DNA associated 3I idiotype. This idiotype is present on a high percentage of anti-DNA antibodies in approximately 80% of SLE patients1,2. In this study, we employed PCR to obtain V kappa I germline genes from a lupus patient in order to address the following questions: Do the V kappa I germline genes of an individual with autoimmune disease differ from those of healthy individuals? What V kappa I genes are used to encode autoantibodies and are they used to encode protective antibodies also? Does the V kappa I gene family display peculiarities in V gene segment rearrangement or somatic mutation? Our analysis shows that the coding region sequences of germline genes of an autoimmune individual are highly homologous to those of non-autoimmune individuals. In addition, the same germline genes can be utilized to encode antibodies to both exogenous and self antigens. While rearranged V kappa genes are ordinarily derived from the J kappa proximal region of the V kappa locus, V kappa I genes encoding autoantibodies derive primarily from the J kappa distal region. It is not yet clear if this applies equally to V kappa I encoded antibodies directed to foreign antigen.


Subject(s)
Autoantibodies/genetics , Genes, Immunoglobulin , Immunoglobulin Variable Region/genetics , Immunoglobulin kappa-Chains/genetics , Lupus Erythematosus, Systemic/genetics , Base Sequence , Humans , Lupus Erythematosus, Systemic/immunology , Molecular Sequence Data
14.
J Clin Invest ; 94(2): 532-8, 1994 Aug.
Article in English | MEDLINE | ID: mdl-8040307

ABSTRACT

The 8.12 idiotype characterizes a subpopulation of anti-DNA antibodies in patients with systemic lupus erythematosus (SLE). The idiotype is present on lambda light chains and has previously been shown to be exclusively encoded by V lambda II light chains. RFLP analysis of the V lambda II gene family has shown the family to consist of 10 to 15 members. Thus far, the sequences of seven V lambda II germline genes are reported in the literature with one of these a pseudogene. To identify the V lambda II genes that encode 8.12 positive antibodies and to further characterize the V lambda II family, germline V lambda II clones were derived from a patient with SLE. Two libraries were constructed: a genomic DNA library and a library of PCR-derived V lambda II gene products obtained using a conserved V lambda II leader region primer and a primer for the nonamer region 3' of the coding sequence. We now describe seven new germline genes, two of which are pseudogenes. Comparison of V lambda II germline genes to sequences of 8.12 positive light chains produced by EBV-transformed B cell lines show that all 8.12 positive light chains are encoded by a limited number of highly homologous members of the V lambda II family. 8.12 negative V lambda II encoded light chains also derive from a limited number of V lambda II genes, suggesting that only a subset of the apparently available V lambda II genes are commonly expressed.


Subject(s)
Genes, Immunoglobulin , Immunoglobulin Variable Region/genetics , Immunoglobulin lambda-Chains/genetics , Lupus Erythematosus, Systemic/genetics , Amino Acid Sequence , Base Sequence , Gene Library , Humans , Molecular Sequence Data , Polymerase Chain Reaction
16.
J Exp Med ; 174(6): 1639-52, 1991 Dec 01.
Article in English | MEDLINE | ID: mdl-1660528

ABSTRACT

Anti-double-stranded DNA antibodies are the hallmark of the disease systemic lupus erythematosus and are believed to contribute to pathogenesis. While a large number of anti-DNA antibodies from mice with lupus-like syndromes have been characterized and their variable region genes sequenced, few human anti-DNA antibodies have been reported. We describe here the variable region gene sequences of eight antibodies produced by Epstein-Barr virus (EBV)-transformed B cells that bear the 3I idiotype, an idiotype expressed on anti-DNA antibodies and present in high titer in patients with systemic lupus. The comparison of these antibodies to the light chains of 3I+ myeloma proteins and serum antibodies reveals that EBV transformation yields B cells producing antibodies representative of the expressed antibody repertoire. The analysis of nucleotide and amino acid sequences of these antibodies suggests the first complementarity determining region of the light chain may be important in DNA binding and that paradigms previously generated to account for DNA binding require modification. The understanding of the molecular genetics of the anti-DNA response requires a more complete description of the immunoglobulin germ line repertoire, but data reported here suggest that somatic diversification is a characteristic of the anti-DNA response.


Subject(s)
Antibodies, Antinuclear/genetics , Immunoglobulin Idiotypes/analysis , Amino Acid Sequence , Base Sequence , Cell Line, Transformed , Genes, Immunoglobulin , Herpesvirus 4, Human , Humans , Immunoglobulin Heavy Chains/genetics , Immunoglobulin Variable Region/genetics , Molecular Sequence Data , Mutation
17.
J Immunol ; 147(8): 2771-6, 1991 Oct 15.
Article in English | MEDLINE | ID: mdl-1680918

ABSTRACT

We report the cDNA sequence of an expressed human V lambda II gene and present an RFLP analysis of the Ig gene family defined by this clone. This V lambda II gene was expressed in a monoclonal B cell line generated from a patient with SLE by transformation with EBV. The encoded lambda L chain displays the 8.12 Id, an Id common to anti-DNA antibodies from patients with SLE. Using a coding region probe we estimate from Southern blot analysis that the germline V lambda II gene family contains at least 15 members. Many of the V lambda II restriction fragments are polymorphic both in SLE patients and in nonautoimmune individuals. EcoRI, HindIII, and TaqI RFLP analyses of the V lambda II gene family and EcoRI analysis of the C lambda gene family reveal no polymorphisms specific to SLE. Observed V lambda II and C lambda allele frequencies are the same among SLE patients and nonautoimmune individuals, and show no evidence of linkage disequilibrium between the two loci.


Subject(s)
Genes, Immunoglobulin , Immunoglobulin Constant Regions/genetics , Immunoglobulin Variable Region/genetics , Immunoglobulin lambda-Chains/genetics , Lupus Erythematosus, Systemic/immunology , Polymorphism, Genetic , Alleles , Base Sequence , Cloning, Molecular , Haplotypes , Humans , Lupus Erythematosus, Systemic/genetics , Molecular Sequence Data , Polymorphism, Restriction Fragment Length
18.
J Clin Invest ; 87(5): 1519-25, 1991 May.
Article in English | MEDLINE | ID: mdl-1708781

ABSTRACT

This study describes a methodology for generating stable, cloned, EBV-transformed IgG- and IgM-producing human B cell lines. Using these lines we have characterized immunoglobulin V gene utilization in an anti-DNA-associated idiotypic system. The 31 anti-DNA-associated idiotype is encoded preferentially by the VK1 gene family, and, in all probability, reflects a germ line gene-encoded framework determinant. Analysis of these lines indicates that the DNA-binding antibodies produced by B cell lines from SLE patients may differ from DNA binding myeloma proteins and from natural autoantibodies.


Subject(s)
Antibodies, Antinuclear/analysis , B-Lymphocytes/immunology , Immunoglobulin G/biosynthesis , Immunoglobulin Idiotypes/analysis , Immunoglobulin M/biosynthesis , Cell Line , DNA/metabolism , Epitopes/analysis , Genes, Immunoglobulin , Herpesvirus 4, Human/genetics , Humans , Immunoglobulin Isotypes/analysis , Lupus Erythematosus, Systemic/immunology
19.
J Clin Invest ; 85(5): 1401-9, 1990 May.
Article in English | MEDLINE | ID: mdl-2110188

ABSTRACT

We report the molecular characterization of 2A4, an IgG, DNA-binding antibody bearing the 3I and F4 idiotypes which are associated with anti-DNA antibodies in serum of patients with systemic lupus erythematosus (SLE). The antibody is produced by an EBV-transformed B cell line derived from a patient with multiple myeloma whose myeloma protein is also an IgG, 3I-reactive, F4-reactive, DNA-binding immunoglobulin, although the 2A4 antibody does not itself represent the myeloma protein. The 2A4 heavy chain is encoded by a VH4 gene, a D-D gene fusion and the JH6 gene; the light chain is derived from a Vk1 gene and the Jk2 gene. This is the first human antibody shown to have a CDR3 encoded by a D-D fusion. DNA sequence analysis of the 2A4 VH gene together with a Southern blot of genomic DNA probed with a 2A4 VH-specific oligonucleotide strongly suggest it to be somatically mutated. The data provide evidence that human autoantibodies can be products of somatically mutated genes and suggest that the 2A4 antibody may reflect the selective pressure of antigen.


Subject(s)
Antibodies, Anti-Idiotypic/genetics , DNA/immunology , Immunoglobulin G/genetics , Immunoglobulin Heavy Chains/genetics , Immunoglobulin Idiotypes/genetics , Immunoglobulin Light Chains/genetics , Lupus Erythematosus, Systemic/immunology , Amino Acid Sequence , Base Sequence , Cloning, Molecular , Humans , Immunoglobulin Isotypes/genetics , Immunoglobulin Variable Region/genetics , Lupus Erythematosus, Systemic/genetics , Lymphocytes/immunology , Molecular Sequence Data , Oligonucleotide Probes
20.
Blood ; 75(7): 1518-24, 1990 Apr 01.
Article in English | MEDLINE | ID: mdl-1690580

ABSTRACT

We studied the expression of CD5 and immunoglobulin variable gene families in a panel of monoclonal Epstein-Barr virus (EBV) transformed lines, chronic lymphocytic leukemias (CLLs) and CD5+ and CD5- B-cell lymphomas. The CD5 gene expression was in all cases identical to that of T-cell malignancies. The utilization of the various VH and VK gene families was roughly proportional to the estimated gene family size in EBV lines obtained from adult healthy subjects. In contrast we found a statistically significant biased usage of VH6 in CLL and VH5 in CD5+ lymphomas as compared with EBV lines, and of VKIII in both CLL and CD5+ lymphomas as compared with EBV lines. Some differences in the variable gene usage were also noted when comparing CD5+ and CD5- lymphomas. These findings are analyzed in the context of possible mechanisms involved in the malignant transformation of CD5+ B cells.


Subject(s)
Antigens, CD/genetics , Antigens, Differentiation/genetics , Gene Expression , Immunoglobulin Variable Region/genetics , Leukemia, Lymphocytic, Chronic, B-Cell/immunology , Lymphoma/immunology , Antigens, CD/analysis , B-Lymphocytes/immunology , CD5 Antigens , Cell Line , Cell Transformation, Viral , DNA Probes , Genes, Immunoglobulin , Herpesvirus 4, Human/genetics , Humans , Leukemia, Lymphocytic, Chronic, B-Cell/genetics , Lymph Nodes/immunology , Lymph Nodes/pathology , Lymphoma/genetics , Lymphoma/pathology , Multigene Family , Receptors, Antigen, B-Cell/analysis
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