Page 542 - Clinical Immunology_ Principles and Practice ( PDFDrive )
P. 542

CHaPTEr 36  Immunodeficiencies at the Interface of Innate and Adaptive Immunity                 521


                                                            51
           and mild CMC in the absence of other clinical manifestations.    this chapter. We thank all the members of the Human Genetics
           The three homozygous mutations identified, S38L, Q329X, and   of Infectious Diseases Laboratory for helpful discussions. The
           Q441X, affect both IL-17 and IFN-γ immunity. As predicted by   Laboratory of Human Genetics of Infectious Diseases is supported
           studies in mice, the lack of functional ROR-γT protein prevents   by grants from the Rockefeller University Center for Clinical
           the development of IL-17-producing T cells, accounting for the   and the Rockefeller University. The Laboratory of Human Genetics
           chronic candidiasis observed in these patients. Surprisingly, the   of Infectious Diseases is supported by the March of Dimes, the
           patients also lacked mucosal-associated invariant T (MAIT) cells   ANR, the INSERM, the FRM, and the PHRC.
           and invariant natural killer T cells (iNKT), which normally
           produce IFN-γ and can inhibit intracellular mycobacterial replica-  Please check your eBook at https://expertconsult.inkling.com/
           tion. Moreover, their conventional CD8  α/β and  γ/δ T cells,   for self-assessment questions. See inside cover for registration
           unlike their CD4 α/β T and NK cells, produced only very small   details.
           amounts of IFN-γ. ROR-γ/ROR-γT thus plays a critical role in
           MAIT and iNKT development, and in the capacity of CD8 and
           γ/δ T cells to make IFN-γ. This results in a profound impairment   REFERENCES
           of IFN-γ production by lymphocytes, leading to susceptibility
                              51
           to mycobacterial disease.  Antibiotic treatment can be combined   1.  Bustamante J, et al. Mendelian susceptibility to mycobacterial disease:
           with IFN-γ injection in cases of disseminated infection. The   genetic, immunological, and clinical features of inborn errors of
                                                                    IFN-gamma immunity. Semin Immunol 2014;26:454–70.
           vaccination of these patients with live BCG is contraindicated.  2.  Kreins AY, et al. Human TYK2 deficiency: mycobacterial and viral
             Overall, these studies strongly suggest that IL-17 immunity   infections without hyper-IgE syndrome. J Exp Med 2015;212:1641–62.
           plays a crucial role in defense against CMC in humans. The   3.  Casrouge A, et al. Herpes simplex virus encephalitis in human UNC-93B
           careful clinical description of a large series of patients would be   deficiency. Science 2006;314:308–12.
           required to determine the role of these cytokines more precisely.  4.  Zhang SY, et al. TLR3 deficiency in patients with herpes simplex
                                                                    encephalitis. Science 2007;317:1522–7.
           CONCLUSIONS                                             5.  Perez de Diego R, et al. Human TRAF3 adaptor molecule deficiency leads
                                                                    to impaired Toll-like receptor 3 response and susceptibility to herpes
                                                                    simplex encephalitis. Immunity 2010;33:400–11.
                                                                   6.  Herman M, et al. Heterozygous TBK1 mutations impair TLR3 immunity
               ON THE HOrIZON                                       and underlie herpes simplex encephalitis of childhood. J Exp Med
            •  Unexplained infectious diseases occur in patients, in children in par-  2012;209:1567–82.
              ticular, as a result of an inborn error of immunity.  7.  Sancho-Shimizu V, et al. Herpes simplex encephalitis in children with
            •  Patients with severe infectious disease should be repeatedly inves-  autosomal recessive and dominant TRIF deficiency. J Clin Invest
              tigated even if all standard immunological explorations are normal.  2011;121:4889–902.
            •  The exploration of these defects, by application of powerful next-  8.  Lim HK, et al. TLR3 deficiency in herpes simplex encephalitis: high allelic
              generation deep-sequencing technologies, provides tools for molecular   heterogeneity and recurrence risk. Neurology 2014;83:1888–97.
              diagnosis and genetic counseling and opens up exciting new perspec-  9.  Andersen LL, et al. Functional IRF3 deficiency in a patient with herpes
              tives benefiting patients.                            simplex encephalitis. J Exp Med 2015;212:1371–9.
            •  The identification of these defects will also guide rational treatment   10.  Ciancanelli MJ, et al. Infectious disease. Life-threatening influenza and
              based on improvements in our understanding of these diseases’   impaired interferon amplification in human IRF7 deficiency. Science
              pathogenesis.                                         2015;348:448–53.
                                                                  11.  Picard C, et al. Pyogenic bacterial infections in humans with IRAK-4
                                                                    deficiency. Science 2003;299:2076–9.
           An understanding of the molecular basis of these PIDs affecting   12.  von Bernuth H, et al. Pyogenic bacterial infections in humans with
           the innate immune responses mediated by IFN-γ, IFN-α/β/λ,   MyD88 deficiency. Science 2008;321:691–6.
           IL-17, TIRs, or NF-κB has provided detailed insight into the   13.  Picard C, et al. Clinical features and outcome of patients with IRAK-4
           pathogenesis of infections in affected patients, paving the way   and MyD88 deficiency. Medicine (Baltimore) 2010;89:403–25.
                                                      52
           for genetic counseling and rational treatment design.  These   14.  Doffinger R, et al. X-linked anhidrotic ectodermal dysplasia with
           PIDs should be sought in patients with unexplained infectious   immunodeficiency is caused by impaired NF-kappaB signaling. Nat Genet
           diseases, whether caused by a single or multiple infectious agents,   2001;27:277–85.
                                                            53
           even if all standard immunological explorations are normal.    15.  Courtois G, et al. A hypermorphic IkappaBalpha mutation is associated
           Interestingly, even common infectious  diseases, such as TB,   with autosomal dominant anhidrotic ectodermal dysplasia and T cell
                                                                    immunodeficiency. J Clin Invest 2003;112:1108–15.
           invasive pneumococcal disease, and HSE may be favored by   16.  Picard C, JCasanova JL, Puel A. Infectious diseases in patients with
           mendelian immune disorders. The discovery of many new PIDs   IRAK-4, MyD88, NEMO, or IkappaBalpha deficiency. Clin Microbiol Rev
           opens  up exciting new  perspectives,  not  only  increasing  our   2011;24:490–7.
           understanding of immunity to pathogens but also benefiting   17.  Puel A, et al. Chronic mucocutaneous candidiasis in humans with inborn
           patients. It is thought that most children with severe infectious   errors of interleukin-17 immunity. Science 2011;332:65–8.
           diseases probably suffer from an underlying PID, and they should,   18.  Ling Y, et al. Inherited IL-17RC deficiency in patients with chronic
           therefore, be repeatedly investigated for known and unknown   mucocutaneous candidiasis. J Exp Med 2015;212:619–31.
           immunodeficiency conditions.                           19.  Boisson B, et al. An ACT1 mutation selectively abolishes interleukin-17
                                                                    responses in humans with chronic mucocutaneous candidiasis. Immunity
                                                                    2013;39:676–86.
           ACKNOWLEDGMENTS                                        20.  Toubiana J, et al. Heterozygous STAT1 gain-of-function mutations
                                                                    underlie an unexpectedly broad clinical phenotype: an international
           We thank our laboratory colleagues, our collaborators at Necker   survey of 274 patients from 167 kindreds. Blood 2016;127:3154–64.
           Hospital for Sick Children and elsewhere, and patients and families   21.  Casanova JL, Abel L. Genetic dissection of immunity to mycobacteria: the
           for their assistance in making possible the studies contained in   human model. Annu Rev Immunol 2002;20:581–620.
   537   538   539   540   541   542   543   544   545   546   547