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van Tilburg SJ, Jacobs BC, Ooijevaar-de Heer P, Fokkink WJR, Huizinga R, Vidarsson G, Rispens T. Novel approach to monitor intravenous immunoglobulin pharmacokinetics in humans using polymorphic determinants in IgG1 constant domains. Eur J Immunol 2021; 52:609-617. [PMID: 34854474 DOI: 10.1002/eji.202149653] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 11/20/2021] [Indexed: 12/12/2022]
Abstract
Clinical efficacy of intravenous immunoglobulin treatment (IVIg) is related to its pharmacokinetic (PK) profile. Its usual evaluation, by measuring serum total IgG levels, is imprecise, because IVIg cannot be distinguished from endogenous IgG. We developed ELISAs to specifically monitor the PK of IVIg using the polymorphic determinants G1m(a), G1m(x), and G1m(f). The specificity of the IgG1 allotype assays was sufficient to determine IVIg concentrations as low as 0.1 mg/mL in sera from individuals not expressing the respective markers. IVIg was quantified in posttreatment serum from patients with Guillain-Barré syndrome (GBS) by measuring IgG1 allotypes not expressed endogenously. After serotyping, 27/28 GBS patients were found eligible for IVIg monitoring using one or two genetic markers. In 17 cases, IVIg levels could be determined by both anti-G1m(a) and anti-G1m(x) measurement, showing significant correlation. Longitudinal monitoring of IVIg PK in seven GBS patients showed potential differences in clearance of total IgG versus IVIg-derived IgG, highlighting that total IgG measurements may not accurately reflect IVIg PK. To summarize, anti-IgG1 allotype assays can discriminate between endogenous IgG and therapeutic polyclonal IgG. These assays will be an important tool to better understand the variability in IVIg PK and treatment response of all patients treated with IVIg.
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Affiliation(s)
- Sander J van Tilburg
- Department of Immunology, Erasmus MC University Medical Center, Rotterdam, The Netherlands
| | - Bart C Jacobs
- Department of Immunology, Erasmus MC University Medical Center, Rotterdam, The Netherlands.,Department of Neurology, Erasmus MC University Medical Center, Rotterdam, The Netherlands
| | - Pleuni Ooijevaar-de Heer
- Department of Immunopathology, Sanquin Research and Landsteiner Laboratory, Amsterdam, The Netherlands
| | - Willem-Jan R Fokkink
- Department of Immunology, Erasmus MC University Medical Center, Rotterdam, The Netherlands.,Department of Neurology, Erasmus MC University Medical Center, Rotterdam, The Netherlands
| | - Ruth Huizinga
- Department of Immunology, Erasmus MC University Medical Center, Rotterdam, The Netherlands
| | - Gestur Vidarsson
- Department of Experimental Immunohematology, Sanquin Research and Landsteiner Laboratory, Amsterdam, The Netherlands
| | - Theo Rispens
- Department of Immunopathology, Sanquin Research and Landsteiner Laboratory, Amsterdam, The Netherlands
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Hanssens LS, Cellauro S, Duchateau J, Casimir GJ. Immunoglobulin G: A useful outcome marker in the follow-up of cystic fibrosis patients? Immun Inflamm Dis 2021; 9:608-614. [PMID: 33783131 PMCID: PMC8127551 DOI: 10.1002/iid3.426] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 01/03/2021] [Revised: 03/11/2021] [Accepted: 03/15/2021] [Indexed: 01/03/2023]
Abstract
Background and Methods Hypergammaglobulinemia (hyper‐IgG) and hypogammaglobulinemia (hypo‐IgG) have been reported in patients with cystic fibrosis (CF). Although the clinical respiratory course is paradoxically different, depending on the IgG status, this association remains elusive. Therefore, we performed a longitudinal study to assess the annual evolution of IgG profiles in a cohort of pediatric patients with CF, from their diagnosis until 2016. We then compared clinical findings with the patients’ IgG status to determine whether IgG status could reflect the respiratory clinical course of patients with CF. Results Among the 66 patients with CF that were aged between 12 months and 18 years in 2016 (mean age: 9.3 years [SD: 5.2]), hypo‐IgG was observed in 15.2% and no hyper‐IgG was identified. Longitudinal assessment since diagnosis revealed no hyper‐IgG but 33.3% of patients had at least one sample showing hypo‐IgG, among which two patients displayed persistent hypo‐IgG. The number of pulmonary exacerbations, duration of antibiotic therapy, and erythrocyte sedimentation rate were all lower in hypo‐IgG patients. No difference was observed for the genotype, chronic Pseudomonas aeruginosa or Staphylococcus aureus infection, and in the parameters of lung function. Conclusion The IgG profile of pediatric patients with CF has changed over recent decades, particularly with regard to hyper‐IgG. In a significant portion of the pediatric CF population, hypo‐IgG is transient and only identifiable in longitudinal assessments. This study reinforces that hypo‐IgG patients paradoxically present a more favorable course of clinical status. Therefore, IgG levels could be a useful outcome marker in the follow‐up of patients with CF. Abnormal immunoglobulin G (IgG) levels have been described in patients with cystic fibrosis (CF). With this longitudinal study, we sought to determine whether IgG status could reflect the respiratory clinical course of CF patients. The assessment in 2016 identified 15.2% of 66 pediatric patients as hypo‐IgG, whereas no hyper‐IgG was highlighted. The longitudinal assessment of IgG since diagnosis revealed no hyper‐IgG and hypo‐IgG was transient in at least one‐third of our patients, except for two, who both displayed persistent hypo‐IgG. Therefore, three populations can be identified, according to the patient's IgG profile during their follow‐up: a first with persistent hypo‐IgG since diagnosis; a second with a transient deficiency, which likely normalizes in adolescence; a third whose IgG remains within a normal range. CF patients with hypo‐IgG appear to be protected from pulmonary exacerbations and therefore could present a more favorable respiratory course, even with low IgG levels since diagnosis. This suggests that IgG levels could be a useful outcome marker in CF patient follow‐up in order to predict their respiratory clinical course.
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Affiliation(s)
- Laurence S Hanssens
- Department of Pediatric Pulmonology and Cystic Fibrosis Clinic, Hôpital Universitaire des Enfants Reine Fabiola, Université Libre de Bruxelles (ULB), Brussels, Belgium
| | - Sarah Cellauro
- Department of Pediatric Pulmonology and Cystic Fibrosis Clinic, Hôpital Universitaire des Enfants Reine Fabiola, Université Libre de Bruxelles (ULB), Brussels, Belgium
| | - Jean Duchateau
- Laboratoire Académique de Pédiatrie, Hôpital Universitaire des Enfants Reine Fabiola, Université Libre de Bruxelles (ULB), Brussels, Belgium
| | - Georges J Casimir
- Department of Pediatric Pulmonology and Cystic Fibrosis Clinic, Hôpital Universitaire des Enfants Reine Fabiola, Université Libre de Bruxelles (ULB), Brussels, Belgium.,Laboratoire Académique de Pédiatrie, Hôpital Universitaire des Enfants Reine Fabiola, Université Libre de Bruxelles (ULB), Brussels, Belgium
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Borremans B, Vossen R, Becker-Ziaja B, Gryseels S, Hughes N, Van Gestel M, Van Houtte N, Günther S, Leirs H. Shedding dynamics of Morogoro virus, an African arenavirus closely related to Lassa virus, in its natural reservoir host Mastomys natalensis. Sci Rep 2015; 5:10445. [PMID: 26022445 PMCID: PMC4448520 DOI: 10.1038/srep10445] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Accepted: 04/10/2015] [Indexed: 12/15/2022] Open
Abstract
Arenaviruses can cause mild to severe hemorrhagic fevers. Humans mainly get infected through contact with infected rodents or their excretions, yet little is known about transmission dynamics within rodent populations. Morogoro virus (MORV) is an Old World arenavirus closely related to Lassa virus with which it shares the same host species Mastomys natalensis. We injected MORV in its host, and sampled blood and excretions at frequent intervals. Infection in adults was acute; viral RNA disappeared from blood after 18 days post infection (dpi) and from excretions after 39 dpi. Antibodies were present from 7 dpi and never disappeared. Neonatally infected animals acquired a chronic infection with RNA and antibodies in blood for at least 3 months. The quantified excretion and antibody patterns can be used to inform mathematical transmission models, and are essential for understanding and controlling transmission in the natural rodent host populations.
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Affiliation(s)
- Benny Borremans
- Evolutionary Ecology Group, University of Antwerp, Antwerp, Belgium
| | - Raphaël Vossen
- Evolutionary Ecology Group, University of Antwerp, Antwerp, Belgium
| | | | - Sophie Gryseels
- Evolutionary Ecology Group, University of Antwerp, Antwerp, Belgium
| | - Nelika Hughes
- Evolutionary Ecology Group, University of Antwerp, Antwerp, Belgium
| | - Mats Van Gestel
- Evolutionary Ecology Group, University of Antwerp, Antwerp, Belgium
| | | | - Stephan Günther
- Bernhard-Nocht-Institute for Tropical Medicine, Hamburg, Germany
| | - Herwig Leirs
- Evolutionary Ecology Group, University of Antwerp, Antwerp, Belgium
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Oxelius VA, Krueger R, Ahlstedt S, Keil T, Lau S, Wahn U. Innate IgG molecules and innate B cells expressed by immunoglobulin constant heavy G chain (Fcγ) genetic marker genes are involved in the 'allergic march' of IgE sensitization in children. Int Arch Allergy Immunol 2015; 166:25-9. [PMID: 25765251 DOI: 10.1159/000371351] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Accepted: 12/03/2014] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Interindividual variations of immunoglobulin constant heavy G chain (IGHG) genes on chromosome 14q32.3 are identified by alternative genetic markers (GM) of IgG3, IgG1 and IgG2, respectively. They express structurally and functionally innate IgG molecules and B cells, associated with allergic disease, replicated in several studies. MATERIALS AND METHODS 1-year-old and 10-year-old, IgE-sensitized and non-sensitized children from the German Multicenter Allergy Study birth cohort were assessed by new serological methods for the mendelian IGHG (Fcγ) (GM) genes, as innate IgG molecules and innate B cells. RESULTS Food allergy sensitization in thirty-five 1-year-old children (124 not sensitized) was associated with the IGHG*bfn haplotype and B*(bfn) cells (OR 1.9, 95% CI 1.2-3.1; p = 0.010). Aeroallergen sensitization in ninety-nine 10-year-old children (95 not sensitized) was associated with the same genes (OR 1.4, 95% CI 1.02-1.9; p = 0.034). The IgE sensitization was most prominent in the restrictive homozygous IGHG*bfn/*bfn diplotype, 34% at age 1, increasing to 60% at age 10, rating the highest numbers of positive IgE tests, expressing increased levels of IgE and innate IgG2*n. CONCLUSIONS The IGHG*bfn haplotype (B*(bfn) cells) and increased innate IgG2*n levels are predictive factors for IgE sensitization in childhood. IGHG genes can be assessed for prognostic and preventive purposes in clinical care.
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Affiliation(s)
- Vivi-Anne Oxelius
- Department of Pediatrics and Institute of Laboratory Medicine, Department of Clinical Immunology, University Hospital, Lund University, Lund, Sweden
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Oxelius VA, Pandey JP. Human immunoglobulin constant heavy G chain (IGHG) (Fcγ) (GM) genes, defining innate variants of IgG molecules and B cells, have impact on disease and therapy. Clin Immunol 2013; 149:475-86. [PMID: 24239836 DOI: 10.1016/j.clim.2013.10.003] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2013] [Revised: 09/23/2013] [Accepted: 10/02/2013] [Indexed: 12/15/2022]
Abstract
The distinguished alternative GM allotypes localized in immunoglobulin constant heavy G chain IGHG (Fcγ) (GM) genes on chromosome 14q32.3 define two unique variants of respectively IgG3, IgG1 and IgG2 subclasses, with different structures and functions. The IGHG allele (allotypes), expressed in homozygous or heterozygous forms, are assessed by new serological methods. Fixed combinations of γ3, γ1 and γ2 allotypes constitute the haplotypes, which are indirect markers of B cells. We highlight the role of homozygous IGHG genes with restricted qualities of IgG subclass molecules and B cells. These common Mendelian IGHG genes respond differently to allergens and infections, both bacterial and viral, and to active and passive immunotherapies. IGHG genes have an impact on diseases such as allergy, immunodeficiency, autoimmunity and malignancy. Association/linkage of different IGHG genes gives information about risk/protection, good or bad prognosis, for improvement of clinical care. The IGHG gene map of healthy Caucasians is registered.
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Affiliation(s)
- Vivi-Anne Oxelius
- Department of Pediatrics and Institute of Laboratory Medicine, Department of Clinical Immunology, University Hospital, Lund University, Lund, Sweden.
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6
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Oxelius VA. From genotypes of immunoglobulin constant heavy G chains (Fcγ) (GM) genes (IGHG) to phenotypes in childhood asthma. Int Arch Allergy Immunol 2012; 159:94-102. [PMID: 22573066 DOI: 10.1159/000335592] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2011] [Accepted: 12/05/2011] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND IgE-mediated allergy is associated with immunoglobulin heavy constant G chain (Fcγ) (GM) genes (IGHG) on chromosome 14q32.3. Investigation of the alternative GM allotypes of γ3, γ1 and γ2 chains has disclosed new structural and functional IgG subclasses and B-cell variants, with possible effects on childhood asthma. OBJECTIVE To investigate different IGHG (GM) gene complexes in a childhood asthma population for allergy parameters. METHODS IGHG alleles and correlated allotypic (allelic) IgG subclass levels were analyzed with a sensitive indirect competitive ELISA in 10-year-old children with bronchial asthma. Individual IGHG diplotype-, genotype- and haplotype-related B cells were compared for allelic IgG subclass levels, IgE sensitization, IgE, IgA and IgM levels, and numbers of peripheral blood eosinophils and lymphocytes. RESULTS The group with homozygous IGHG*bfn/*bfn (B1/B1 cells) demonstrated low IgG1*f levels (p < 0.001) but increased IgG2*n levels (p < 0.001) together with increasd IgE and IGHG2*n gene dose-dependent IgE sensitization (atopic phenotype). The IGHG*bf-n/*bf-n (B2/B2 cells) demonstrated low IgG1*f (p < 0.05) and IgG2*-n (p < 0.001) and the IGHG*ga-n/*ga-n (B4/B4 cells) low IgG1*a (p < 0.001) and IgG2*-n (p < 0.02) together with low IgE sensitization (non-atopic phenotype). B*(bfn) (B1) and B*(bf-n) (B2) demonstrated increased numbers of peripheral blood eosinophils, compared to B*(gan) (B4) cells, which demonstrated increased peripheral blood CD8 lymphocytes instead. CONCLUSION IGHG diplotypes present different phenotypes in childhood asthma. The IGHG2*n dose relationship to IgE sensitization and increased IgG2*n levels in IgE sensitized are risk markers for IgE-mediated asthma. The opposite IGHG2*-n presents non-IgE-mediated asthma and IgG subclass deficiencies.
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Affiliation(s)
- Vivi-Anne Oxelius
- Department of Pediatrics and Institute of Laboratory Medicine, Department of Clinical Immunology, University Hospital, Lund University, Lund, Sweden.
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Díaz B, Sanjuan I, Gambón F, Loureiro C, Magadán S, González-Fernández A. Generation of a human IgM monoclonal antibody directed against HLA class II molecules: a potential agent in the treatment of haematological malignancies. Cancer Immunol Immunother 2009; 58:351-60. [PMID: 18677479 PMCID: PMC11030852 DOI: 10.1007/s00262-008-0558-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2007] [Accepted: 06/27/2008] [Indexed: 11/30/2022]
Abstract
Major histocompatibility complex (MHC) class II molecules have been considered as a good target molecule for use in immunotherapy, because of the high expression in some lymphoma and leukaemia cells and, also, because of their restricted expression on human cells (monocytes, dendritic, B lymphocytes, thymic epithelial cells, and some cytokine-activated cells, such as T lymphocytes). We have obtained a human IgM monoclonal antibody directed against human leukocyte antigen (HLA) class II molecules, using transgenic mice carrying human Ig genes. The antibody BH1 (IgM/kappa isotype) recognises HLA-class II on the surface of tumour cells from patients suffering from haematological malignancies, such as chronic and acute lymphocytic leukaemias, non-Hodgkin lymphomas and myeloid leukaemias. Interestingly, functional studies revealed that BH1 mAb recognises and kills very efficiently tumour cells from several leukaemia patients in the presence of human serum as a source of complement. These results suggest that this human IgM monoclonal antibody against HLA-class II could be considered as a potential agent in the treatment of several malignancies.
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Affiliation(s)
- Belén Díaz
- Immunology Unit, Universidad de Vigo, Edificio de Ciencias Experimentales, Campus Lagoas Marcosende, Pontevedra, Spain.
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Hajighasemi F, Khoshnoodi J, Shokri F. Development of two murine monoclonal antibodies recognizing human nG1m(a)-like isoallotypic markers. Hybridoma (Larchmt) 2009; 27:473-9. [PMID: 19108620 DOI: 10.1089/hyb.2008.0043] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Antigenic determinants of immunoglobulin molecules are categorized into three groups: idiotypes, isotypes, and allotypes. An isoallotype is defined as an isotypic determinant in one or more subclasses and an allotype in another subclass of a given isotype. The isoallotype nG1m(a), formerly called non-a, is an allotype located on human IgG1 molecules lacking the G1m(a) allotype. This marker, however, is also detectable on all human IgG2 and IgG3 molecules. Anti-isoallotypic antibodies are useful tools for structural studies of immunoglobulins, forensic science, and epidemiological demographic investigations. In this study, two murine monoclonal antibodies (MAbs) recognizing nG1m(a)-like epitope(s) were generated against a human IgG myeloma protein. These MAbs are produced by hybridoma clones (4F18B12 and 6F18D1) obtained by fusion of SP2/0 myeloma cells with splenocytes from BALB/c mice immunized with heavy chain of a human IgG3 myeloma protein. These MAbs reacted with Fc, but not Fab fragment of the immunizing IgG3 paraprotein. Specificity of the MAbs was further analyzed using a panel of purified myeloma proteins and polyclonal IgG3, including IgG1 (n = 9), IgG2 (n = 4), IgG3 (n = 8), and IgG4 (n = 6) subclasses. Our results demonstrated that these MAbs reacted with linear epitope(s) located on heavy chain of all IgG2 and IgG3 molecules tested and some paraproteins of IgG1 subclass, but none of the IgG4 molecules. So these MAbs seem to recognize nG1m(a)-like isoallotypic marker. These MAbs showed no cross-reactivity with serum of other species tested. Both MAbs belonged to IgG1 subclass with affinity constants of 4.5 x 10(9) mol(-1) (4F18B12) and 3.46 x 10(9) mol(-1) (6F18D1), respectively. These MAbs might be used as a tool to detect nG1m(a) + IgG molecules.
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Affiliation(s)
- Fatemeh Hajighasemi
- Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
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Skattum L, Gullstrand B, Holmström E, Oxelius VA, Truedsson L. Serum bactericidal activity against Neisseria meningitidis in patients with C3 nephritic factors is dependent on IgG allotypes. Clin Immunol 2008; 129:123-31. [DOI: 10.1016/j.clim.2008.06.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2008] [Revised: 05/26/2008] [Accepted: 06/13/2008] [Indexed: 11/29/2022]
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Oxelius VA, Ochs HD, Hammarström L. Restricted immunoglobulin constant heavy G chain genes in primary immunodeficiencies. Clin Immunol 2008; 128:190-8. [DOI: 10.1016/j.clim.2008.03.520] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2007] [Revised: 03/26/2008] [Accepted: 03/26/2008] [Indexed: 11/30/2022]
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Abstract
The IGHG (ImmunoGlobulin constant Heavy G chain) genes are situated close to the IGHE gene on chromosome 14q32, 5'mu, delta, gamma3, gamma1, alpha1, gamma2, gamma4, epsilon, alpha2, 3', in linkage disequilibrium. The polymorphism of gamma3, gamma1 and gamma2 genes, is investigated as alternative allotypes. They are inherited in a Mendelian fashion and are expressed randomly in allelic exclusion. The alternative and functionally different gamma3, gamma1 and gamma2 gene variants, are found in four IGHG haplotypes, coding 4 B-cell variants: IGHG*bfn (=B1-cells), IGHG*bf-n (=B2-cells), IGHG*gan (=B3-cells) and IGHG*ga-n (=B4-cells). The dominance of the IGHG2*n allele from the IGHG*bfn haplotype (=B1-cells) has been shown in repeated investigations, namely in patients with asthma and allergy with increased serum levels of IgE > 600 ku/l and more often so in those with IgE > 1,000 ku/l or IgG4>1 g/l, in childhood asthma patients with mean level of IgE = 1,762 ku/l and in allergen exposed individuals developing laboratory animal allergy. In children with non-atopy and mean IgE level = 9.5 ku/l there is instead a dominance of the alternative allotypes from the IGHG*ga-n (=B4-cells) with IGHG2*-n alleles. In a case-control study allergic children with a family history of allergy, clinically manifest allergy and/or positive SPT, the IGHG*bfn haplotype (=B1-cells) with the IGHG2*n allele dominates, with increased risk of atopy and the IGHG*bf-n haplotype (=B2-cells) with the IGHG2*-n allele is infrequent with low risk, probably protective against atopy. The phenotypic expressions of the IGHG*bfn haplotype (=B1 cells) and IGHG*bfn/*bfn diplotypes (B1/B1-cells) are increased IgG2*n allotype together with increased IgE serum levels and IgE sensitisation in agreement with atopy. The alternative IGHG*ga-n/*ga-n diplotype (B4/B4-cells) express low IgG1*a- and IgG2*-n allotypes, together with low IgE and non-IgE sensitisation, in agreement with non-atopy. Together these studies have given us a greater understanding of the involvement of IGHG genes, IGHG coded B-cells and immunochemical and functional variants of IgG molecules describing different forms of asthma and allergy, which will improve diagnoses and treatment.
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Affiliation(s)
- Vivi-Anne Oxelius
- Department of Pediatrics, University Hospital, Lund University, 221 85, Lund, Sweden.
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Gustafsson PM, Oxelius VA, Nilsson S, Kjellman B. Association between Gm allotypes and asthma severity from childhood to young middle age. Respir Med 2007; 102:266-72. [PMID: 17933503 DOI: 10.1016/j.rmed.2007.09.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2007] [Revised: 09/04/2007] [Accepted: 09/05/2007] [Indexed: 10/22/2022]
Abstract
Immunoglobulin constant heavy G chain (IGHG) gene polymorphisms are associated with atopy and can be determined by the serum Gm allotypes. We studied whether certain polymorphisms are related to asthma severity and to the extent or intensity of allergic sensitization in asthmatic subjects followed from childhood to young middle age. Fifty-five subjects (28 males) with childhood asthma were all followed-up prospectively on six occasions from a mean age of 9 to 35 years in a study including asthma severity scoring, spirometry, skin prick, and specific serum IgE antibody testing. At the last visit, extended lung function tests and a cold air challenge were performed, and IGHG gene polymorphisms were identified by the alternative serum IgG subclass allotypes, employing ELISA and double immunodiffusion. The 19 subjects with the homozygous IGHG*bf/*bf genotype (originating from the IGHG3*b and the IGHG1*f alleles, which are in strong linkage disequilibrium), showed significantly higher asthma scores, lower airway function, and greater bronchodilator responses from childhood to adulthood, and in middle age greater airway hyperresponsiveness, compared to the subjects with the IGHG*bf/*ga or IGHG*ga/*ga genotypes. Among the subjects sensitized to animal danders, those with the IGHG*bf/*bf genotype showed the highest specific IgE levels. In conclusion, IGHG gene polymorphisms were associated with the severity and outcome of childhood asthma, and with the intensity of allergic sensitization.
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Affiliation(s)
- Per M Gustafsson
- Department of Clinical Physiology, Queen Silvia Children's Hospital, 416 85 Göteborg, Sweden.
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Abstract
BACKGROUND Several candidate genes have been found to be associated with the inflammatory response of IgE-mediated allergy, so also the immunoglobulin constant heavy G chain (IGHG) genes. The IGHG genes are situated close to the IGHE gene on chromosome 14q32, 5'mu, delta, gamma3, gamma1, alpha1, gamma2, gamma4, epsilon, alpha2, 3'. They are inherited in a Mendelian fashion and expressed randomly in allelic exclusion. The alternative and functionally different gamma3, gamma1 and gamma2 gene variants are found in four IGHG haplotypes, coding four B cell variants. OBJECTIVE The aim of this study was to assess the frequency of different IGHG genes in relation to phenotypes associated with allergy, in a case-control study. METHODS We identified the constant heavy-chain genes of IgG in 198 allergic and non-allergic children participating in the Phase II of the International Study of Asthma and Allergy in Children. The IGHG genes were assessed by the alternative serum IgG subclass allotypes expressing the alternative alleles of gamma3, gamma1 and gamma2 genes, using ELISA and double immunodiffusion. RESULTS The IGHG*bfn haplotype (=B1 cells) and IGHG2*n allele dominated (51% vs. 24%, P=0.002) and the IGHG*bf-n haplotype (=B2 cells) was infrequent (16% vs. 52%, P < 0.001) in allergic children with a family history of allergy, clinical manifest allergy and positive skin prick test (SPT). The frequency of IGHG genes was similar in children with maternal and paternal heredity and in children with wheezing, eczema or rhinitis, as well as in children with different positive SPT. The IGHG*bfn haplotype with the IGHG2*n allele was strongly associated with heredity for allergy. The IGHG*bf-n haplotype was inversely related to allergy. Conclusions IgG allotypes, immunochemical and functional variants of IgG molecules from IGHG genes are associated with atopy. The IGHG*bfn haplotype (=B1 cells) with the IGHG2*n allele dominates, associated with an increased risk for atopy. In contrast, the IGHG*bf-n haplotype (=B2 cells) with the IGHG2*-n allele is associated with low risk.
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Affiliation(s)
- V-A Oxelius
- Department of Pediatrics, University Hospital, Lund University, Lund, Sweden.
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Katchar K, Taylor CP, Tummala S, Chen X, Sheikh J, Kelly CP. Association between IgG2 and IgG3 subclass responses to toxin A and recurrent Clostridium difficile-associated disease. Clin Gastroenterol Hepatol 2007; 5:707-13. [PMID: 17544998 DOI: 10.1016/j.cgh.2007.02.025] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
BACKGROUND & AIMS Individuals who mount a significant serum immunoglobulin (Ig)G response to toxin A are protected against recurrent Clostridium difficile-associated disease (CDAD). We investigated whether humoral immune deficiencies and/or specific IgG subclass responses are associated with recurrent CDAD. METHODS We compared the clinical characteristics and humoral immune responses of 13 patients with recurrent CDAD with 13 matched controls with a single CDAD episode. We measured the serum IgG titers to tetanus and diphtheria toxoids, as well as total and toxin A- and toxin B-specific serum IgG, IgA, and IgG subclass concentrations. RESULTS There were no differences between the single and recurrent CDAD subjects in terms of age, sex, ethnicity, or other potential confounding variables. The total duration of diarrhea in patients with recurrent CDAD was greater (median, 62 vs 17 days; P = .005). IgG titers to tetanus and diphtheria toxoids, total IgG, and IgG subclass levels were similar in both groups. The total IgA was somewhat lower in those with recurrent CDAD (204 vs 254 mg/dL; P = .05). IgA, IgG, IgG1, and IgG4 anti-toxin A and anti-toxin B levels were similar in both groups. However, IgG2 and IgG3 anti-toxin A levels were significantly lower in the recurrent group (P = .01 and .001, respectively). CONCLUSIONS Subjects with recurrent CDAD did not show evidence of widespread humoral immune deficiency or of IgG subclass deficiency. Their low serum IgG anti-toxin A concentrations reflected selectively reduced IgG2 and IgG3 subclass responses. Measurement of specific IgG2/3 anti-toxin A may be useful in selecting patients for treatment with agents to prevent recurrent CDAD.
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Affiliation(s)
- Kianoosh Katchar
- Department of Medicine, Division of Gastroenterology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02215, USA.
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Jönsson G, Oxelius VA, Truedsson L, Braconier JH, Sturfelt G, Sjöholm AG. Homozygosity for the IgG2 subclass allotype G2M(n) protects against severe infection in hereditary C2 deficiency. J Immunol 2006; 177:722-8. [PMID: 16785571 DOI: 10.4049/jimmunol.177.1.722] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Homozygous C2 deficiency (C2D) is the most common deficiency of the classical complement pathway in Western countries. It is mostly found in patients with autoimmune disease or susceptibility to bacterial infections and in healthy persons. We wished to assess to what extent other immunological factors might explain differences of susceptibility to infections in C2D. For this reason, 44 Swedish patients with C2D were stratified with regard to the severity of documented infections. Investigations of IgG subclass levels, IgG subclass-specific GM allotypes, concentrations of factor B, properdin, and factor H, and polymorphisms of mannan-binding lectin and the Fc receptors FcgammaRIIa and FcgammaRIIIb were performed. Homozygosity for the G2M*n allele, which is known to promote Ab responses to polysaccharide Ags, was strongly associated with the absence of severe infections (p < 0.001) in the patients, suggesting a major protective role. The combination of mannan (or mannose)-binding lectin and C2 deficiency was found to be a minor susceptibility factor for invasive infection (p = 0.03). Low concentrations of IgG2 and factor B might sometimes contribute to susceptibility to infection. Other factors investigated did not appear to be important. In conclusion, the findings indicated that efficient Ab responses to polysaccharides are protective against severe infection in C2D. Implications with regard to vaccination should be considered.
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Affiliation(s)
- Göran Jönsson
- Department of Infectious Diseases, University Hospital of Lund, SE-221 85 Lund, Sweden.
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Skov M, Pandey JP, Pressler T, Høiby N, Koch C. Immunoglobulin allotypes and IgG subclass antibody response to Aspergillus fumigatus in cystic fibrosis patients. J Cyst Fibros 2005; 3:173-8. [PMID: 15463904 DOI: 10.1016/j.jcf.2004.05.048] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2003] [Accepted: 05/10/2004] [Indexed: 10/26/2022]
Abstract
BACKGROUND A majority of patients with cystic fibrosis (CF) become colonised with Aspergillus fumigatus (Af.), but only a minority develops allergic bronchopulmonary aspergillosis (ABPA). ABPA is associated with increased levels of specific immunoglobulin G (IgG) anti-Af. antibodies with a characteristic IgG subclass distribution. We examined whether this characteristic immune response was under the influence of GM and KM allotypes, which are genetic markers (antigenic determinants) on gamma- and kappa-light chains, respectively. METHODS Sera from 233 CF patients were typed for seven GM determinants and two KM determinants. The types were correlated to IgG subclass anti-Af. antibody levels and to the presence or absence of Af. colonisation as well as ABPA. RESULTS The IgG2 antibody level was significantly higher in heterozygous GM (1,2,17 23 5,21 and 1,3,17 23 5,21) compared to homozygous GM allotypes (p = 0.02). Patients with the same allotypes tended to have higher IgG1 (p = 0.051). In patients with ABPA, being heterozygous for G1M and G3M was linked to higher IgG4 and lower IgG3 as compared to the other genotypes. The KM markers did not influence the antibody levels. The allotype GM(3 23 5), associated with atopic bronchial asthma, tended to make a relatively larger group in ABPA patients compared to non-ABPA and patients not colonised with Af. (p = 0.09). CONCLUSIONS An influence of the GM allotypes on the immune response to Af. and on the development of ABPA in patients with CF is suggested.
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Affiliation(s)
- M Skov
- Department of Pediatrics, National University Hospital, CF-centre 5003, Blegdamsvej 9, Copenhagen 2100, Denmark.
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Pachman LM, Lipton R, Ramsey-Goldman R, Shamiyeh E, Abbott K, Mendez EP, Dyer A, Curdy DM, Vogler L, Reed A, Cawkwell G, Zemel L, Sandborg C, Rivas-Chacon R, Hom C, Ilowite N, Gedalia A, Gitlin J, Borzy M. History of infection before the onset of juvenile dermatomyositis: results from the National Institute of Arthritis and Musculoskeletal and Skin Diseases Research Registry. ACTA ACUST UNITED AC 2005; 53:166-72. [PMID: 15818654 DOI: 10.1002/art.21068] [Citation(s) in RCA: 109] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE To obtain data concerning a history of infection occurring in the 3 months before recognition of the typical weakness and rash associated with juvenile dermatomyositis (JDM). METHODS Parents or caretakers of children within 6 months of JDM diagnosis were interviewed by the registry study nurse concerning their child's symptoms, environment, family background, and illness history. Physician medical records were reviewed, confirming the JDM diagnosis. RESULTS Children for which both a parent interview and physician medical records at diagnosis were available (n = 286) were included. Diagnoses were as follows: definite/probable JDM (n = 234, 82%), possible JDM (n = 43, 15%), or rash only (n = 9, 3%). The group was predominantly white (71%) and had a girl:boy ratio of 2:1. Although the mean age at onset was 6.7 years for girls and 7.3 years for boys, 25% of the children were < or =4 years old at disease onset. In the 3 months before onset, 57% of the children had respiratory complaints, 30% had gastrointestinal symptoms, and 63% of children with these symptoms of infection were given antibiotics. CONCLUSION This study provides evidence that JDM affects young children. The symptoms of the typical rash and weakness often follow a history of respiratory or gastrointestinal complaints. These data suggest that the response to an infectious process may be implicated in JDM disease pathogenesis.
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Affiliation(s)
- Lauren M Pachman
- The Northwestern University's Feinberg School of Medicine, Chicago, Illinois 60614, USA.
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Abstract
AIM Respiratory syncytial virus (RSV) is a prominent cause of airway morbidity in children under 1 y of age. It is assumed that host factors influence the severity of disease presentation, and thus the need for hospitalization. The variation of IGHG genes from chromosome 14q32 are linked to serum IgG subclass levels but also to the variations in IgG responses to pneumococcal, meningococcal and Haemophilus influenzae antigens. The aim of this investigation was to clarify whether IGHG genes are involved in the development of severe RSV lower respiratory tract infection (LRTI). METHODS The alternative expressions of IGHG3(b) and (g), IGHG1(f) and (a), and IGHG2(n) and (-n) genes were studied in a cohort of 49 previously healthy children hospitalized for RSV LRTI. The gene frequencies were compared to a population of healthy individuals. RESULTS The homozygous IGHG2(-n/-n) genotypes dominated in hospitalized children with severe RSV infection: 55.1%, compared with 34.2% in the healthy population (OR 2.3; p = 0.004). The IGHG2 genotypes containing (n/n) and (n/-n) were significantly decreased. The IGHG(bf-n) alleles were significantly increased (OR 1.7; p = 0.025) and the IGHG(bfn) alleles significantly decreased (OR 0.5; p = 0.005). CONCLUSION The IGHG(bf-n) allele and homozygous IGHG2(-n/-n) genotypes are associated with the development of severe RSV LRTI.
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Omazic B, Hentschke P, Näsman-Björk I, Mattsson J, Oxelius VA, Ringdén O, Barkholt L, Permert J, Lundkvist I. Reconstitution of the Ig Heavy Chain CDR3 Repertoire after Allogeneic Haematopoietic Stem Cell Transplantation with Myeloablative or Reduced-Intensity Conditioning Regimens. Scand J Immunol 2005; 61:72-81. [PMID: 15644125 DOI: 10.1111/j.0300-9475.2005.01528.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The objective of this study was to investigate B-lymphocyte reconstitution in patients undergoing allogeneic haematopoietic stem cell transplantation (HSCT) after myeloablative conditioning (MAC) or reduced-intensity conditioning (RIC) regimens. B-lymphocyte reconstitution was studied by monitoring the CDR3 repertoire with spectratyping. We demonstrate a delay in the recovery of the B-lymphocyte repertoire, measured by variation in size distribution of the immunoglobulin H CDR3 in patients conditioned with RIC compared to MAC. We found no general explanation for this finding, but when clinical data for each patient were studied in detail, we could identify a cause for the oligoclonality of the B-lymphocyte repertoire after HSCT with RIC for each of the patients. Older patients and donors, low cell dose at transplantation, relapse, graft-versus-host disease (GVHD) and its treatment as well as cytomegalovirus infection and its treatment are all possible causes for the restriction of the B-lymphocyte repertoire observed in this study. Taken together, reconstitution of the B-lymphocyte repertoire after HSCT is a process dependent on multiple factors and differs between patients. The conditioning regimen may be of importance, but data from this study suggest that individual factors and the various complications occurring after HSCT are more likely to determine the development of the B-lymphocyte repertoire.
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Affiliation(s)
- B Omazic
- Arvid Wretlind Laboratory at the Center for Surgical Sciences, Karolinska Institutet, Karolinska University Hospital, Huddinge, Stockholm,Sweden.
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Abstract
PURPOSE OF REVIEW Cytokines are criticalmediators of the immune response. This review focuses on cytokine-specific information from children with juvenile dermatomyositis, and includes pertinent data from adults with polymyositis and dermatomyositis. RECENT FINDINGS Much of the new data concern the role of possible antigens and the definition of genetic control of the immune response in juvenile dermatomyositis. Gene expression profile data of DQA1*0501 (present in 85% of patients) compared with age-matched control subjects show that the initial immune response is an interferon-alpha/beta-induced cascade with secondary stimulation of interferon-gamma. Specific epitopes of group A beta-hemolytic streptococcal M protein, with sequence homology for myosin, elicit both cell-mediated cytotoxicity and tumor necrosis factor-alpha production when incubated with mononuclear cells from children with active juvenile dermatomyositis. Tumor necrosis factor-alpha synthesis is increased in juvenile dermatomyositis patients with the tumor necrosis factor-alpha-308A allele, and is associated with increased thrombospondin-1 (an antiangiogenic agent) production and small vessel occlusion in untreated juvenile dermatomyositis. Studies in adults with polymyositis and dermatomyositis implicate interleukin-1alpha, transforming growth factor-beta, and endothelial cell perturbation early in the disease course. Cultured myoblasts were found to produce interleukin-15, which impacts local T-cell activation and proliferation. SUMMARY The limited data suggest that a possible viral/microbial antigen may elicit an interferon-alpha/beta-induced response, and that antigenic epitopes may be shared. Increased synthesis of tumor necrosis factor-alpha, more common in juvenile dermatomyositis with the tumor necrosis factor-alpha-308A polymorphism, may augment this response and is associated with a wide range of pathologic consequences, as well as disease chronicity and calcifications. The muscle fibers themselves can regulate local inflammation by production of tumor necrosis factor-alpha, interleukin-15 and interleukin-1alpha, and transforming growth factor-beta.
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Affiliation(s)
- Gulbu Uzel
- Feinberg School of Medicine, Northwestern University, Department of Pediatrics, Chicago, Illinois, USA
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Abstract
BACKGROUND Biliary atresia is the commonest cause of pathological jaundice in infants and the leading indication for liver transplantation in children worldwide. The cause and pathogenesis remain largely unknown. Because of clinical heterogeneity and experimental difficulties in addressing molecular mechanisms underlying multifactorial disorders in human beings, we searched for genomic signatures of biliary atresia in affected infants. METHODS We generated pools of biotinylated cRNA from livers of 14 infants with biliary atresia and six with neonatal intrahepatic cholestasis (diseased controls) and hybridised the cRNA against oligonucleotide-based gene chips. Immunohistochemistry and reverse transcriptase (RT)-PCR were used to assess the specificity of the findings and functional commitment of lymphocytes in affected livers. FINDINGS Data filtering, to identify genes that are differentially expressed, and cluster analysis revealed a predominant and coordinated activation of immunity/inflammation genes within the livers of infants with biliary atresia. Most of the genes showed differential lymphocyte function, with activation of osteopontin, a regulator of cell-mediated (T-helper 1 [Th-1]) immunity in T-helper lymphocytes, and suppression of immunoglobulin genes in early stages of disease. These findings were associated with production of interferon gamma in 65% of infants with biliary atresia and no diseased control. However, histologically similar inflammatory infiltrates were present in livers of both groups, implying differential activation states of similar cell types. INTERPRETATION Livers of infants with biliary atresia have a coordinated activation of genes involved in lymphocyte differentiation. Among these genes, the overexpression of osteopontin and interferon gamma points to a potential role of Th-1-like cytokines in disease pathogenesis.
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Affiliation(s)
- Jorge A Bezerra
- Division of Pediatric Gastroenterology, Children's Hospital Medical Center and University of Cincinnati, Cincinnati, OH 45229, USA.
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Abstract
OBJECTIVES Chronic mild neutropenias (NP, i.e. absolute neutrophil blood counts/ANC/0.5-1.5 x 10(9) L(-1)) are accompanied by a variable infection susceptibility, which may or may not be as a result of concomitant conditions. Here, we assessed whether such patients also displayed an immunoglobulin deficiency and if this condition contributed to infection proneness. DESIGN, SETTING AND SUBJECTS Thirty consecutive adult Caucasian patients with chronic mild NP were followed at one university hospital for up to 28 years. Comparisons were made with 49 IgG3 deficiency patients at an immunodeficiency clinic. MAIN OUTCOME MEASURES Recorded infections, ANC and serum immunoglobulin levels; flow cytometry assessments of blood lymphocyte subsets and tests for autoimmunity were run to determine neutropenia subtypes. RESULTS Forty per cent of the NP patients were treated for severe or recurrent infections. The mean IgG3 value for the NP patients was significantly lower than for healthy controls (P < 0.005) and 33% of the patients displayed IgG3 values below the reference values (i.e. below 0.21 g L(-1)), and an additional 13% had IgG3 values within the range others consider low (0.21-0.41 g L(-1)). Unexpectedly, neutropenic IgG3 deficiency patients exhibited less infection proneness than those with normal IgG3 values (P=0.03). Patients with autoimmune, large granular lymphocyte-associated or idiopathic NP had IgG3 deficiency in 63, 44 and 38%, respectively. In addition, none of IgG3 deficiency patients followed at the immunodeficiency clinic displayed neutropenia. CONCLUSION IgG3 deficiency is common amongst chronic mild neutropenia patients, particularly in those with autoimmune background, but contributes not significantly to infection susceptibility.
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Affiliation(s)
- R Karlström
- Department of Medicine, Division of Hematology, The Karolinska Institutet at Huddinge University Hospital, S-141 86 Stockholm, Sweden
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Abstract
BACKGROUND The IGHG genes on chromosome 14q32, 5'micron delta gamma3 gamma1alpha1 gamma2 gamma4 epsilon alpha2 3', as studied by Gm allotypes, are involved in the inheritance of atopy. The 5'micron delta b f alpha1 n gamma4 epsilon alpha2 3', Gm(bfn) haplotype of the genetic B1-cell variant has been found to be associated with the atopic phenotype of children with bronchial asthma. METHODS An indirect competitive enzyme-linked immunosorbent assay for quantitation in serum of the alternative serum Gm allotypes from the gamma3-, gamma1-, and gamma2 loci and radial immunodiffusion for quantitation of IgG subclasses were used. Children with the genetic B1-cell variants B1/B1 (= Gm[bfn/bfn]), B1/B2 (=Gm[bfn/bf-n]), and B1/B4 (=Gm[bfn/ga-n]) and bronchial asthma were investigated and compared to healthy children of the same age and B-cell type. RESULTS The three groups with B1/B1, B1/B2, and B1/B4 cells exhibited increased IgE. In both homozygous and heterozygous B1 or Gm(bfn), the serum G1m(f) levels from gamma1 loci were significantly downregulated to 75% of normal, while G2m(n) from gamma2 loci were significantly upregulated to about double the normal level. In heterozygous patients with additional B2 or B4 cells, the G2m(-n) levels from gamma2 loci were instead downregulated. G1m(a) from gamma1 of B4 cells was also downregulated. CONCLUSIONS Children with atopic bronchial asthma demonstrated an imbalanced class switch in rearrangement of the genes for IgG. The activity of G1m(f) from the gamma1 locus was downregulated, but G2m(n) from gamma2 was upregulated together with the closely situated epsilon locus downstream of the IGH genes. Low levels of G1m(f), Glm(a), and G2m(-n) indicated a low pressure of infections. The imbalanced activation of the IGH genes in more hygienic environments might be one explanation of the increased prevalence of atopy in children in recent decades.
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Affiliation(s)
- V A Oxelius
- Department of Pediatrics, University Hospital, University of Lund, Sweden
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Affiliation(s)
- V A Oxelius
- Department of Pediatrics & Clinical Immunology, University Hospital, University of Lund, Sweden
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