ABSTRACT
PURPOSE: To define the clinical and histological characteristics of nephritis in patients with X-linked agammaglobulinemia (XLA) and their immunological profiles. METHODS: The clinical, immunological, and histological findings of nine patients with XLA and nephritis were retrospectively analyzed. RESULTS: Based on kidney histological findings, patients with XLA and nephritis could be divided into two groups, viz., chronic glomerulonephritis (CGN) and tubulointerstitial nephritis (TIN). The two groups showed different immunological profiles. Patients in the CGN group exhibited an atypical immunological profile of XLA, with pathogenic leaky B cells producing immunoglobulins that may play a role in forming immune complexes and causing immune-mediated glomerulonephritis. In contrast, patients in the TIN group exhibited a typical immunological profile of XLA, suggesting that antibody-independent/other BTK-dependent mechanisms, or immunoglobulin replacement therapy (IgRT)-related immune/nonimmune-mediated nephrotoxicity causes TIN. CONCLUSION: Nephritis occurring in patients with XLA could have links between their renal pathology and immunological status. Careful observation is recommended to detect kidney pathology in patients with XLA on IgRT.
Subject(s)
Agammaglobulinemia , Genetic Diseases, X-Linked , Phenotype , Humans , Agammaglobulinemia/immunology , Agammaglobulinemia/diagnosis , Agammaglobulinemia/genetics , Genetic Diseases, X-Linked/immunology , Genetic Diseases, X-Linked/genetics , Genetic Diseases, X-Linked/diagnosis , Genetic Diseases, X-Linked/complications , Male , Adolescent , Child , Adult , Retrospective Studies , Child, Preschool , Young Adult , Agammaglobulinaemia Tyrosine Kinase/genetics , Nephritis, Interstitial/immunology , Nephritis, Interstitial/diagnosis , Kidney/pathology , Kidney/immunology , B-Lymphocytes/immunology , Female , Glomerulonephritis/immunology , Glomerulonephritis/diagnosis , Nephritis/immunology , Nephritis/diagnosis , Nephritis/etiologySubject(s)
Hypersensitivity , Humans , Hypersensitivity/therapy , Allergens , Immunoglobulin E , Immunotherapy , Plant ProteinsABSTRACT
T cell receptor beta chain (TCRß) diversity (Dß) gene segments are highly conserved across evolution, with trout Dß1 sequence identical to human and mouse Dß1. A key conserved feature is enrichment for glycine in all three Dß reading frames (RFs). Previously, we found that replacement of mouse Dß1 with a typical immunoglobulin DH sequence, which unlike Dß is enriched for tyrosine, leads to an increase in the use of tyrosine in TCRß complementarity determining region 3 (CDR-B3) after thymic selection, altering T cell numbers, CDR-B3 diversity, and T cell function. To test whether the incorporation of charged amino acids into the Dß sequence in place of glycine would also influence T cell biology, we targeted the TCRß locus with a novel glycine-deficient DßDKRQ allele that replaces Dß1 coding sequence with charged amino acids in all three reading frames. Developing T cells using DßDKRQ expressed TCR CDR-B3s depleted of tyrosine and glycine and enriched for germline-encoded lysine, arginine, and glutamine. Total thymocytes declined in number during the process of ß selection that occurs during the transition from the DN3bc to DN4 stage. Conventional thymocyte and T cell numbers remained reduced at all subsequent thymic stages and in the spleen. By contrast, regulatory T cell numbers were increased in Peyer's patches and the large intestine. In terms of functional consequences, T cell reactivity to an ovalbumin immunodominant epitope was reduced. These findings buttress the view that natural selection of Dß sequence is used to shape the pre-immune TCRß repertoire, affecting both conventional and regulatory T cell development and influencing epitope recognition.
Subject(s)
Amino Acids , Complementarity Determining Regions , Mice , Animals , Humans , Complementarity Determining Regions/genetics , Amino Acids/genetics , Amino Acids/metabolism , Amino Acid Sequence , Receptors, Antigen, T-Cell, alpha-beta/genetics , Immunodominant Epitopes , Germ Cells/metabolism , Tyrosine/metabolism , Glycine/metabolismABSTRACT
The early B cell protein λ5 is an essential component of the surrogate light chain and the preB cell receptor (preBCR), which is critical for optimal B cell development. To investigate the effect of λ5 and/or B cells on bone acquisition over time, we developed a panel of JH -/- , λ5-/-, JH -/- λ5-/-, and wild-type (WT) BALB/c mice and then studied postnatal bone development and aging in these mice at one, six, twelve, and twenty-two months of age. The trabecular bone volume over total volume (BV/TV) in JH -/- mice was similar to WT mice at all ages. In contrast, at six months of age and thereafter, λ5-/- and JH -/- λ5-/- mice demonstrated a severe decrease in trabecular bone mass. Surprisingly, bone mass in six-month-old λ5-/- and JH -/- λ5-/- mice was similar to or even lower than in aged (twenty-two-months) WT mice, suggesting accelerated skeletal aging. The postnatal development and the acquisition of cortical bone mass in JH -/- λ5-/- mice were generally comparable to WT. However, JH -/- λ5-/- mice showed a significant decrease in cortical BV/TV at six- and twelve months of age. To examine the contribution of λ5 and B cells to postnatal bone synthesis, we separately transplanted whole bone marrow cells from JH -/- λ5-/- and WT mice into irradiated JH -/- λ5-/- and WT recipients. WT recipients of JH -/- λ5-/- marrow cells failed to show acquisition of trabecular bone mass, whereas transplanting WT marrow cells into JH -/- λ5-/- recipients led to the recovery of trabecular bone mass. Transfer of WT marrow cells into JH -/- λ5-/- mice promoted synthesis of new cortical and trabecular bone. Our findings indicate that λ5 plays a major role in preserving bone mass during postnatal development and skeletal aging which is distinct from its role in B cell development. The absence of both λ5 and B cells in JH -/- λ5-/- mice leads to delayed acquisition of cortical bone during postnatal development. Dissecting the mechanism(s) by which λ5 regulates bone homeostasis may provide new avenues for the treatment of age-related loss of bone mass and osteoporosis.
Subject(s)
B-Lymphocytes , Pre-B Cell Receptors , Aging , Animals , B-Lymphocytes/metabolism , Bone Density , Immunoglobulin Light Chains, Surrogate/metabolism , Mice , Mice, Inbred BALB C , Pre-B Cell Receptors/metabolismABSTRACT
[This corrects the article DOI: 10.3389/fimmu.2022.906649.].
ABSTRACT
We hypothesized that the scarcity of N-nucleotides might contribute to the inability of the neonate to mount a robust allergic immune response. To test this, we used terminal deoxyribunucleotidyl Transferase deficient (TdT-/-) mice, which express "fetal-like" T cell receptor and immunoglobulin repertoires with largely germline-encoded CDR3 regions. Intraperitoneal sensitization was followed by aerosol provocation with either PBS or the allergen OVA in both TdT-/- mice and wild-type mice to develop allergic respiratory inflammation. The effects of this procedure were investigated by lung function test, immunological analysis of serum and brochoalveolar lavage. The local TH2 cytokine milieu was significantly attenuated in TdT-/- mice. Within this group, the induction of total IgE levels was also significantly reduced after sensitization. TdT-/- mice showed a tendency toward reduced eosinophilic inflow into the bronchial tubes, which was associated with the elimination of respiratory hyperreactivity. In conclusion, in a murine model of allergic airway inflammation, the expression of fetal-like antigen receptors was associated with potent indications of a reduced ability to mount an asthma phenotype. This underlines the importance of somatically-generated antigen-receptor repertoire diversity in type one allergic immune responses and suggests that the fetus may be protected from allergic responses, at least in part, by controlling N addition.
Subject(s)
Asthma/genetics , DNA Nucleotidylexotransferase/genetics , Animals , Asthma/immunology , Asthma/pathology , DNA Nucleotidylexotransferase/immunology , Disease Models, Animal , Gene Deletion , Immunity, Innate , Inflammation/genetics , Inflammation/immunology , Inflammation/pathology , Mice , Mice, Inbred BALB CABSTRACT
Enrichment for tyrosine in immunoglobulin CDR-H3 is due in large part to natural selection of germline immunoglobulin DH sequence. We have previously shown that when DH sequence is modified to reduce the contribution of tyrosine codons, epitope recognition is altered and B cell development, antibody production, autoantibody production, and morbidity and mortality following pathogen challenge are adversely affected. TCRß diversity (Dß) gene segment sequences are even more highly conserved than DH, with trout Dß1 identical to human and mouse Dß1. We hypothesized that natural selection of Dß sequence also shapes CDR-B3 diversity and influences T cell development and T cell function. To test this, we used a mouse strain that lacked Dß2 and contained a novel Dß1 allele (DßYTL) that replaces Dß1 with an immunoglobulin DH, DSP2.3. Unlike Dß1, wherein glycine predominates in all three reading frames (RFs), in DSP2.3 there is enrichment for tyrosine in RF1, threonine in RF2, and leucine in RF3. Mature T cells using DßYTL expressed TCRs enriched at particular CDR-B3 positions for tyrosine but depleted of leucine. Changing Dß sequence altered thymocyte and peripheral T cell numbers and the T cell response to an ovalbumin immunodominant epitope. The differences in tyrosine content might explain, at least in part, why TCRs are more polyspecific and of lower affinity for their cognate antigens than their immunoglobulin counterparts.
Subject(s)
Complementarity Determining Regions , Genes, Immunoglobulin Heavy Chain , Genes, T-Cell Receptor beta , Immunoglobulin Heavy Chains/metabolism , Receptors, Antigen, T-Cell, alpha-beta/metabolism , T-Lymphocytes/metabolism , Thymocytes/metabolism , Animals , Immunization , Immunodominant Epitopes , Immunoglobulin Heavy Chains/genetics , Lymphocyte Activation , Mice, Inbred C57BL , Mice, Knockout , Ovalbumin/administration & dosage , Ovalbumin/immunology , Phenotype , Receptors, Antigen, T-Cell, alpha-beta/genetics , T-Lymphocytes/immunology , Thymocytes/immunology , TyrosineABSTRACT
We have previously shown that the sequence of the immunoglobulin diversity gene segment (D H ) helps dictate the structure and composition of complementarity determining region 3 of the immunoglobulin heavy chain (CDR-H3). In order to test the role of germline D sequence on the diversity of the preimmune TCRß repertoire of T cells, we generated a mouse with a mutant TCRß DJC locus wherein the Dß2-Jß2 gene segment cluster was deleted and the remaining diversity gene segment, Dß1 (IMGT:TRDB1), was replaced with DSP2.3 (IMGT:IGHD2-02), a commonly used B cell immunoglobulin D H gene segment. Crystallographic studies have shown that the length and thus structure of TCR CDR-B3 places amino acids at the tip of CDR-B3 in a position to directly interact with peptide bound to an MHC molecule. The length distribution of complementarity determining region 3 of the T cell receptor beta chain (CDR-B3) has been proposed to be restricted largely by MHC-specific selection, disfavoring CDR-B3 that are too long or too short. Here we show that the mechanism of control of CDR-B3 length depends on the Dß sequence, which in turn dictates exonucleolytic nibbling. By contrast, the extent of N addition and the variance of created CDR3 lengths are regulated by the cell of origin, the thymocyte. We found that the sequence of the D and control of N addition collaborate to bias the distribution of CDR-B3 lengths in the pre-immune TCR repertoire and to focus the diversity provided by N addition and the sequence of the D on that portion of CDR-B3 that is most likely to interact with the peptide that is bound to the presenting MHC.
Subject(s)
B-Lymphocytes/immunology , Complementarity Determining Regions/genetics , Immunoglobulin D/genetics , Immunoglobulin Heavy Chains/genetics , Receptors, Antigen, T-Cell, alpha-beta/genetics , Animals , Antibody Diversity , Cells, Cultured , Genetic Engineering , Genetic Variation , Germ Cells , Mice , Mice, Inbred C57BLABSTRACT
Paraneoplastic syndromes are a rare clinical presentation of tumor thought to affect 0.01% of patients with cancer. Paraneoplastic syndromes present a diagnostic challenge as a wide variety of signs and symptoms may appear. This study examines the use of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) as a diagnostic imaging tool for detecting tumor in suspected paraneoplastic syndrome cases. This single-center retrospective study included patients with suspected paraneoplastic syndrome who underwent whole-body 18F-FDG PET/CT scan between December 2005 and December 2016. Associated clinical data were gathered via electronic chart review. Patient records were reviewed for age, sex, clinical signs and symptoms, ancillary diagnostic procedures, date of diagnosis, and follow-up time. Ninety-nine patients met inclusion criteria for this study. Mean follow-up period was 1.8 years. Cancer prevalence was 12.1%. The 18F-FDG PET/CT results are as follows: 10 true positives, 5 false positives, 82 true negatives, and 2 false negatives. The diagnostic values are as follows: sensitivity 83.3%, specificity 94.3%, positive predictive value 66.7%, and negative predictive value (NPV) 97.6%. The high NPV in our study supports the effectiveness of 18F-FDG PET/CT to rule out tumor in suspected paraneoplastic syndrome. Future research aims to analyze which patients with suspected paraneoplastic syndrome would benefit most from 18F-FDG PET/CT.
ABSTRACT
BACKGROUND: PCV13 (conjugated polysaccharide) and PPSV23 (polysaccharide only) are two licensed vaccines targeting S. pneumoniae. The role of CD4 T-cell responses in pneumococcal vaccines among healthy participants and their impact on antibodies is not yet known. METHODS: Ten adults (5 old and 5 young) received PCV13 (prime) and a year later PPSV23 (boost). Blood samples were collected prior to and multiple time points after vaccination. CD4 T cells responding to CRM197, polysaccharide (PS), CRM197 conjugated polysaccharide (CPS), PCV13 and PPSV23 vaccines were measured by flow cytometry. Serum antibodies were analyzed via multiplex opsonophagocytosis (MOPA) and pneumococcal IgG assays. RESULTS: Vaccine-specific CD4 T cells were induced in all ten vaccinees post PCV13. Older vaccinees mounted higher peak responses and those specific for PCV13 and conjugated PS-1 were more polyfunctional compared to the younger group. Vaccine-elicited peripheral T follicular helper (Tfh) cells were only detected in the younger group who also exhibited a higher fold change in OPA titers post both vaccines. Importantly, Tfh cells following PCV13 correlated only with PCV13 serotype specific OPA titers after PPSV23 vaccination. CONCLUSIONS: These findings demonstrate age related differences in immune response and the potential importance of Tfh in modulating functional antibody responses following pneumococcal vaccination.
Subject(s)
Age Factors , Antibody Formation , CD4-Positive T-Lymphocytes/immunology , Pneumococcal Infections , Pneumococcal Vaccines/immunology , Antibodies, Bacterial/blood , Humans , Immunization, Secondary , Phagocytosis , Pneumococcal Infections/prevention & control , T-Lymphocytes, Helper-Inducer/immunology , Vaccines, ConjugateABSTRACT
Immunoglobulin replacement therapy (IGRT) can protect against lung function decline in CVID. We tested whether increasing IgG dosage was beneficial in patients who exhibited a decline in forced expiratory flow at 25-75% (FEF25-75%) even though they were receiving IgG doses within the therapeutic range. Of 189 CVID patients seen over 12 years, 38 patients met inclusion criteria, were seen on ≥ 3 visits, and demonstrated a ≥ 10% decrease in FEF25-75% from visits 1 to 2. FEF25-75%, forced expiratory flow at 1 s (FEV1), and FEV1/FVC at visit 3 were compared among those with non-dose adjustment (non-DA) versus additional IgG dose adjustment (DA). Three FEF25-75% tiers were identified: top (> 80% predicted), middle (50-80%), and bottom (< 50%). DA and non-DA groups did not differ in clinical infections or bronchodilator use, although the non-DA group tended to use more antibiotics. In the top, normal tier, FEF25-75% increased in DA, but the change did not achieve statistical significance. In the middle moderate obstruction tier, visit 3 FEF25-75% increased among DA but not non-DA sets (11.8 ± 12.4%, p = 0.003 vs. 0.3 ± 9.9%, p = 0.94). Improvement in FEV1/FVC at visit 3 was also significant among DA vs. non-DA (7.2 ± 12.4%, p = 0.04 vs. - 0.2 ± 2.7%, p = 0.85). In the bottom, severe tier, FEF25-75% was unchanged in DA (- 0.5 ± 5.2%, p = 0.79), but increased in non-DA (5.1 ± 5.2%, p = 0.02). Among IGRT CVID patients with moderate but not severe obstruction as assessed by spirometry, increasing IgG dosage led to an increase in FEF25-75% and FEV1/FVC.
Subject(s)
Common Variable Immunodeficiency/drug therapy , Immunoglobulin G/therapeutic use , Immunoglobulins, Intravenous/therapeutic use , Lung/metabolism , Respiratory Function Tests/methods , Adult , Antibiotic Prophylaxis , Biomarkers, Pharmacological , Drug Dosage Calculations , Female , Humans , Lung/pathology , Male , Maximal Midexpiratory Flow Rate , Middle Aged , Treatment OutcomeABSTRACT
In the bone marrow, preB cells are found adjacent to the bone endosteum where bone synthesizing osteoblast and bone resorbing osteoclasts reside. Although there is evidence of interactions between preB and bone cells, the factors that contribute to such interactions are poorly understood. A critical checkpoint for preB cell development assesses the integrity of the nascent immunoglobulin µ heavy chain (HC) by testing whether it can participate in the formation of a preB cell receptor (preBCR), composed of the µ HC and surrogate light chain (LC). In this work, we tested whether loss of preBCR components can affect bone synthesis. A panel of gene targeted mice with sequential blocks in preBCR formation or function [surrogate light chain component lambda 5 deleted (λ5-/-), transmembrane domain of µHC deleted (IgM-mem-/-), and CD19 preBCR co-receptor deleted (CD19-/-)] were evaluated for effects on postnatal bone synthesis. Postnatal bone mass was analyzed in 6 month old mice using µ-CT, histomorphometry and double calcein labeling. Both cortical and trabecular bone mass were significantly decreased in the femurs of the λ5 and IgM-mem deficient mice. Histomorphometric analysis showed a decrease in the numbers of osteoblasts and osteoclasts in all three mutant strains. Double calcein labeling revealed a significant decrease in dynamic synthesis and mineralization of bone in λ5-/- mice. Our data strongly suggest that interference with preBCR formation or function affects bone homeostasis independent of the presence or absence of mature B cells, and that components of the preBCR play important, and potentially distinct, roles in regulating adult bone mass.
Subject(s)
Bone and Bones/immunology , Immunoglobulin Heavy Chains/immunology , Immunoglobulin Light Chains, Surrogate/immunology , Immunoglobulin mu-Chains/immunology , Pre-B Cell Receptors/immunology , Animals , B-Lymphocytes/cytology , B-Lymphocytes/immunology , B-Lymphocytes/metabolism , Bone and Bones/diagnostic imaging , Bone and Bones/metabolism , Femur/diagnostic imaging , Femur/immunology , Femur/metabolism , Homeostasis/immunology , Immunoglobulin Heavy Chains/genetics , Immunoglobulin Heavy Chains/metabolism , Immunoglobulin Light Chains, Surrogate/genetics , Immunoglobulin Light Chains, Surrogate/metabolism , Immunoglobulin mu-Chains/genetics , Immunoglobulin mu-Chains/metabolism , Mice, Inbred C57BL , Mice, Knockout , Osteoblasts/cytology , Osteoblasts/immunology , Osteoblasts/metabolism , Osteoclasts/cytology , Osteoclasts/immunology , Osteoclasts/metabolism , Pre-B Cell Receptors/genetics , Pre-B Cell Receptors/metabolism , Signal Transduction/genetics , Signal Transduction/immunology , X-Ray Microtomography/methodsSubject(s)
Immune System Diseases , Immunoglobulin E , Allergens , Child , Humans , Immunoglobulin G , InfantABSTRACT
Phelan-McDermid syndrome (PMS, OMIM 606232) is a heterozygous contiguous gene microdeletion syndrome occurring at the distal region of chromosome 22q13. This deletion encompasses the SHANK3 gene at 22q13.33, which is thought to be the critical gene for the neurodevelopmental features seen in this syndrome. PMS is typically characterized by intellectual disability, autism spectrum disorder, absent to severely delayed speech, neonatal hypotonia, and dysmorphic features. Two patients presenting with classic clinical features of PMS have been reported to have interstitial microdeletions in the 22q13.2 region that map proximal to the SHANK3 gene (0.54 and 0.72 Mb, respectively). Here, we describe a 13-month-old girl with a de novo 1.16 Mb interstitial deletion in the 22q13.2 region who presented with global developmental delay, subtle dysmorphic features, and immunodeficiency. This deletion overlaps with the two previously published cases and five cases from the DECIPHER database. All eight patients share features common to patients with PMS including developmental delay and language delay, which suggests that this represents a previously unrecognized microdeletion syndrome in the 22q13.2 region. Our patient's deletion encompasses the TCF20 and TNFRSF13C genes, which are thought to play causative roles in the patient's neurodevelopmental and immunological features, respectively.
Subject(s)
B-Cell Activation Factor Receptor/genetics , Chromosome Disorders/diagnosis , Chromosome Disorders/genetics , Phenotype , Transcription Factors/genetics , Alleles , Chromosome Deletion , Chromosomes, Human, Pair 22/genetics , Comparative Genomic Hybridization , Cytogenetic Analysis , Female , Genetic Association Studies , Humans , Infant , MutationABSTRACT
We have developed a very simple method, termed absorbance summation (AS), for comparing protein concentrations between samples in ELISA assays without a standard. This method sums the observed absorbance values from all dilutions to obtain one data point for each sample to be used for comparison. AS is less computationally intensive than fitting sigmoidal curves, and it avoids the difficulty of parameter estimation for samples with absorbance values lying primarily at the lower tail of the curve. Our simulation studies showed that it performs much better than the sigmoidal curve fitting method and the conventional endpoint titer method. The power of this simple method is as high as the formal curve fitting followed by the estimation of area under the curve (AUC).