Mixed T‐ and B Lymphocyte Deficiency Disorders

Mixed immunodeficiency diseases are intrinsic defects of the immune system affecting both B and T cells and thus the adaptive immune system. Mixed or combined immune deficiencies may also be associated with or secondary to other diseases. Patients have severe symptoms and the condition can be fatal unless properly treated. Early and reliable diagnosis is in many instances crucial for the efficient treatment of these diseases since delayed diagnosis and management can cause severe and irreversible complications, even the death of the patient. Combined immunodeficiencies, which are a heterogeneous disease group, appear throughout the immune system and affect several crucial genes and proteins. The symptoms and signs vary significantly between the different forms of combined immunodeficiencies.

Key Concepts:

  • Combined immunodeficiency affects both B and T cells.
  • Lymphocytes are white blood cells including B and T cells.
  • Haematopoietic stem cell transplantation, the intravenous infusion of autologous or allogeneic stem cells collected from bone marrow, peripheral blood or umbilical cord blood, reestablishes haematopoietic function in patients.
  • V(D)J recombination is genetic recombination which randomly selects and assembles segments of genes encoding specific proteins in the immune system.

Keywords: adaptive immunity; immunodeficiency; immune system; B cell; T cell; severe combined immune deficiency

Figure 1. V(D)J recombination process. (a) recombination of the immunoglobulin or TCR gene by random combination of individual regions. (b) detailed description of the stages where recombination deficiency proteins are involved. Note that a number of other factors are also involved but not shown in the figure.
Figure 2. Simplified schematic view of the common (c)–Janus kinase (JAK) 3 signalling pathway. Binding of an interleukin 2 (IL-2) to the receptor on the cell surface triggers cellular signalling reactions in which JAK3 is involved. The signal is further transmitted by signal transducers and activators of transcription (STATs) which, when activated and dimerised, can translocate to the nucleus, where they effect the transcription of genes responsive to cytokines by binding to the activation sequence (GAS) motif.
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 References
    Fischer A (2007) Human primary immunodeficiency diseases. Immunity 27(6): 835–845.
    Fischer A and Cavazzana-Calvo M (2008) Gene therapy of inherited diseases. Lancet 371(9629): 2044–2047.
    Fischer A, Hacein-Bey S and Cavazzana-Calvo M (2002) Gene therapy of severe combined immunodeficiencies. Nature Reviews. Immunology 2(8): 615–621.
    International Union of Immunological Societies Expert Committee on Primary Immunodeficiencies, Notarangelo LD, Fischer A, Geha RS et al. (2009) Primary immunodeficiencies: 2009 update. Journal of Allergy and Clinical Immunology 124(6): 1161–1178.
    Maródi L and Notarangelo LD (2007) Immunological and genetic bases of new primary immunodeficiencies. Nature Reviews. Immunology 7(11): 851–861.
    Minegishi Y (2009) Hyper-IgE syndrome. Current Opinion in Immunology 21(5): 487–492.
    Notarangelo LD (2010) Primary immunodeficiencies. Journal of Allergy and Clinical Immunology 125(2 suppl. 2): S182–S194.
    Notarangelo LD, Lanzi G, Peron S and Durandy A (2006) Defects of class-switch recombination. Journal of Allergy and Clinical Immunology 117(4): 855–864.
    book Ochs HD, Smith CIE and Puck J (2008) Primary Immunodeficiency Diseases. A Molecular and Genetic Approach. Oxford, UK: Oxford University Press.
    Ozcan E, Notarangelo LD and Geha RS (2008) Primary immune deficiencies with aberrant IgE production. Journal of Allergy and Clinical Immunology 122(6): 1054–1062.
    Samarghitean C, Ortutay C and Vihinen M (2009) Systematic classification of primary immunodeficiencies with clustering and network methods bases on clinical, pathological and laboratory parameters. Journal of Immunology 183: 7569–7575.
    Samarghitean C, Väliaho J and Vihinen M (2007) IDR knowledgebase for primary immunodeficiencies. Immunome Research 3: 6. ImmunoDeficiency Resource, http://bioinf.uta.fi/idr/
 Further Reading
    ePath IDbases. http://bioinf.uta.fi/base_root
    book Rezaei N, Aghamohammadi A and Notarangelo LD (2008) Primary Immunodeficiency Disorders. Heidelberg, Germany: Springer.
    book Stiehm ER, Ohcs HD and Winkelstein JA (2004) Immunologic Disorders in Infants Children. Philadelphia, PA: Elsevier Saunders.
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Vihinen, M(Sep 2010) Mixed T‐ and B Lymphocyte Deficiency Disorders. In: eLS. John Wiley & Sons Ltd, Chichester. http://www.els.net [doi: 10.1002/9780470015902.a0002167.pub3]