RESUMO
Increased IgE is a typical feature of allergic rhinitis. Local class-switch recombination has been intimated but B cell precursors and mechanisms remain elusive. Here we describe the dynamics underlying the generation of IgE-antibody secreting cells (ASC) in human nasal polyps (NP), mucosal tissues rich in ASC without germinal centers (GC). Using VH next generation sequencing, we identified an extrafollicular (EF) mucosal IgD+ naïve-like intermediate B cell population with high connectivity to the mucosal IgE ASC. Mucosal IgD+ B cells, express germline epsilon transcripts and predominantly co-express IgM. However, a small but significant fraction co-express IgG or IgA instead which also show connectivity to ASC IgE. Phenotypically, NP IgD+ B cells display an activated profile and molecular evidence of BCR engagement. Transcriptionally, mucosal IgD+ B cells reveal an intermediate profile between naïve B cells and ASC. Single cell IgE ASC analysis demonstrates lower mutational frequencies relative to IgG, IgA, and IgD ASC consistent with IgE ASC derivation from mucosal IgD+ B cell with low mutational load. In conclusion, we describe a novel mechanism of GC-independent, extrafollicular IgE ASC formation at the nasal mucosa whereby activated IgD+ naïve B cells locally undergo direct and indirect (through IgG and IgA), IgE class switch.
Assuntos
Formação de Anticorpos/imunologia , Subpopulações de Linfócitos B/imunologia , Subpopulações de Linfócitos B/metabolismo , Imunoglobulina D/imunologia , Imunoglobulina E/imunologia , Mucosa Nasal/imunologia , Mucosa Nasal/metabolismo , Adulto , Formação de Anticorpos/genética , Células Produtoras de Anticorpos/imunologia , Células Produtoras de Anticorpos/metabolismo , Biologia Computacional , Perfilação da Expressão Gênica , Centro Germinativo/imunologia , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Hipersensibilidade/etiologia , Hipersensibilidade/metabolismo , Switching de Imunoglobulina/genética , Switching de Imunoglobulina/imunologia , Isotipos de Imunoglobulinas/genética , Isotipos de Imunoglobulinas/imunologia , Imunofenotipagem , Pólipos Nasais/etiologia , Pólipos Nasais/metabolismo , Pólipos Nasais/patologia , Pólen/imunologia , Estações do Ano , Hipermutação Somática de ImunoglobulinaRESUMO
Human papilloma virus (HPV) causes a subset of head and neck squamous cell carcinomas (HNSCC) of the oropharynx. We combined targeted DNA- and genome-wide RNA-sequencing to identify genetic variants and gene expression signatures respectively from patients with HNSCC including oropharyngeal squamous cell carcinomas (OPSCC). DNA and RNA were purified from 35- formalin fixed and paraffin embedded (FFPE) HNSCC tumor samples. Immuno-histochemical evaluation of tumors was performed to determine the expression levels of p16INK4A and classified tumor samples either p16+ or p16-. Using ClearSeq Comprehensive Cancer panel, we examined the distribution of somatic mutations. Somatic single-nucleotide variants (SNV) were called using GATK-Mutect2 ("tumor-only" mode) approach. Using RNA-seq, we identified a catalog of 1,044 and 8 genes as significantly expressed between p16+ and p16-, respectively at FDR 0.05 (5%) and 0.1 (10%). The clinicopathological characteristics of the patients including anatomical site, smoking and survival were analyzed when comparing p16+ and p16- tumors. The majority of tumors (65%) were p16+. Population sequence variant databases, including gnomAD, ExAC, COSMIC and dbSNP, were used to identify the mutational landscape of somatic sequence variants within sequenced genes. Hierarchical clustering of The Cancer Genome Atlas (TCGA) samples based on HPV-status was observed using differentially expressed genes. Using RNA-seq in parallel with targeted DNA-seq, we identified mutational and gene expression signatures characteristic of p16+ and p16- HNSCC. Our gene signatures are consistent with previously published data including TCGA and support the need to further explore the biologic relevance of these alterations in HNSCC.
Assuntos
Inibidor p16 de Quinase Dependente de Ciclina/genética , Neoplasias de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Adulto , Idoso , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , DNA Viral/genética , Gerenciamento de Dados , Bases de Dados de Ácidos Nucleicos , Testes Diagnósticos de Rotina , Feminino , Expressão Gênica , Perfilação da Expressão Gênica , Neoplasias de Cabeça e Pescoço/metabolismo , Neoplasias de Cabeça e Pescoço/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Neoplasias Orofaríngeas/genética , Neoplasias Orofaríngeas/metabolismo , Neoplasias Orofaríngeas/virologia , Papillomaviridae/genética , Infecções por Papillomavirus/genética , Infecções por Papillomavirus/metabolismo , Infecções por Papillomavirus/virologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/virologia , TranscriptomaRESUMO
A 36-year-old female patient developed diplopia and an ipsilateral lateral rectus paresis following local anesthetic administration to remove a left maxillary second molar. Complete resolution occurred within 3 hours. The clinical examination and management plan are reviewed for this uncommon occurrence. The relevant anatomical pathways are discussed and illustrated with photographs.