title: Germline CARD11 Mutation in a Patient with Severe Congenital B Cell Lymphocytosis.
abstract: OBJECTIVE
  Activating germline mutations in CARD11 have recently been linked to a rare genetic disorder associated with congenital B cell lymphocytosis. We describe a patient with a similar clinical phenotype who had a de novo germline G123D CARD11 mutation.
  
  
  METHODS
  Whole exome sequencing was performed on DNA from the patient and his biological parents. Laboratory studies examined characteristics of the patient's B and T lymphocytes. A CARD11 cDNA containing the mutation was transfected into a lymphocyte cell line to gain an understanding of its function. RNA sequencing was performed on samples from the patient and from patients with alternate germline CARD11 mutations and differential gene expression analysis was performed.
  
  
  RESULTS
  The patient had a decade-long history of severe polyclonal B lymphocytosis in the 20,000-90,000 lymphocytes/mm(3) range, which was markedly exacerbated by EBV infection and splenectomy at different times. He had a heterozygous germline CARD11 mutation causing a G123D amino acid substitution, which was demonstrated to induce NF-κB activation in unstimulated lymphocytes. In contrast to previous patients with CARD11 mutations, this patient's B cells exhibited higher expression of several cell cycle progression genes, as well as enhanced proliferation and improved survival following B cell receptor stimulation.
  
  
  CONCLUSIONS
  This is the third reported germline and first de novo CARD11 mutation shown to cause congenital B cell lymphocytosis. The mutation was associated with a dramatically greater lymphocytosis than in previously described cases, disproportionate to the level of constitutive NF-κB activation. However, comparative review of the patient's clinical history, combined with additional genomic and functional analyses, underscore other important variables that may affect pathophysiology or regulate mutant CARD11 function in B cell proliferation and disease. We now refer to these patients as having BENTA disease (B cell Expansion with NF-κB and T cell Anergy).
authors.affiliation: Oncogenomics Section, Genetics Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, 37 Convent Drive, Building 37, Room 2016B, Bethesda, MD, 20892, USA.
authors.forename: Andrew S
authors.initials: AS
authors.lastname: Brohl
authors.affiliation: Department of Pharmacology, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Rd., Bethesda, MD, 20814, USA.
authors.forename: Jeffrey R
authors.initials: JR
authors.lastname: Stinson
authors.affiliation: Laboratory of Host Defenses, National Institute of Allergy and Infectious Disease, National Institutes of Health, Bethesda, MD, USA.
authors.forename: Helen C
authors.initials: HC
authors.lastname: Su
authors.affiliation: Department of Pediatrics and Markey Cancer Center, College of Medicine, University of Kentucky, Lexington, KY, USA.
authors.forename: Thomas
authors.initials: T
authors.lastname: Badgett
authors.affiliation: Department of Pathology, College of Medicine, University of Kentucky, Lexington, KY, USA.
authors.forename: Chester D
authors.initials: CD
authors.lastname: Jennings
authors.affiliation: Department of Anatomy, Physiology & Genetics, Uniformed Services University of the Health Sciences, Bethesda, MD, USA.
authors.forename: Gauthaman
authors.initials: G
authors.lastname: Sukumar
authors.affiliation: Oncogenomics Section, Genetics Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, 37 Convent Drive, Building 37, Room 2016B, Bethesda, MD, 20892, USA.
authors.forename: Sivasish
authors.initials: S
authors.lastname: Sindiri
authors.affiliation: Immunopathogenesis Section, Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD, USA.
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.affiliation: Immunopathogenesis Section, Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD, USA.
authors.forename: Lela
authors.initials: L
authors.lastname: Kardava
authors.affiliation: Immunopathogenesis Section, Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD, USA.
authors.forename: Susan
authors.initials: S
authors.lastname: Moir
authors.affiliation: Department of Anatomy, Physiology & Genetics, Uniformed Services University of the Health Sciences, Bethesda, MD, USA.
authors.forename: Clifton L
authors.initials: CL
authors.lastname: Dalgard
authors.affiliation: Department of Pediatrics and Markey Cancer Center, College of Medicine, University of Kentucky, Lexington, KY, USA.
authors.forename: Jeffrey A
authors.initials: JA
authors.lastname: Moscow
authors.affiliation: Oncogenomics Section, Genetics Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, 37 Convent Drive, Building 37, Room 2016B, Bethesda, MD, 20892, USA. khanjav@mail.nih.gov.
authors.forename: Javed
authors.initials: J
authors.lastname: Khan
authors.affiliation: Department of Pharmacology, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Rd., Bethesda, MD, 20814, USA. andrew.snow@usuhs.edu.
authors.forename: Andrew L
authors.initials: AL
authors.lastname: Snow
mesh_terms: D019943:Amino Acid Substitution; D017209:Apoptosis / Q000235:genetics; D001402:B-Lymphocytes / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D001483:Base Sequence; D053468:CARD Signaling Adaptor Proteins / Q000737:chemistry / Q000235:genetics*; D049109:Cell Proliferation / Q000235:genetics; D002648:Child; D004247:DNA / Q000235:genetics; D020869:Gene Expression Profiling; D018095:Germ-Line Mutation; D006162:Guanylate Cyclase / Q000737:chemistry / Q000235:genetics*; D006801:Humans; D008213:Lymphocyte Activation / Q000235:genetics; D008218:Lymphocytosis / Q000151:congenital* / Q000235:genetics* / Q000276:immunology; D008297:Male; D050505:Mutant Proteins / Q000737:chemistry / Q000235:genetics; D020125:Mutation, Missense; D016328:NF-kappa B / Q000378:metabolism
chemical_list: D053468:CARD Signaling Adaptor Proteins; D050505:Mutant Proteins; D016328:NF-kappa B; D004247:DNA; C426242:CARD11 protein, human; D006162:Guanylate Cyclase
keywords: B-cell lymphocytosis; BENTA; CARD11; NF-κB; congenital