title: Evaluation of the T helper 17 cell specific genes and the innate lymphoid cells counts in the peripheral blood of patients with the common variable immunodeficiency.
abstract: BACKGROUND
  Common variable immunodeficiency (CVID) is characterized by a deficiency in the immune system with a heterogeneous collection of disorders resulting in antibody deficiency and recurrent infections. T helper 17 (Th17) cells promote B-cell survival and synergize with the B-cell activating factor to induce their differentiation into the plasma cells. A sub-population of innate lymphoid cells (ILCs) also produces interleukin 17 (IL-17). This study aimed to measure the Th17 specific genes and ILCs counts in the CVID patients in comparison with control subjects.
  
  
  METHODS
  Total messenger ribonucleic acid (mRNA) was extracted from the whole blood samples of 10 CVID patients and 10 healthy individuals. IL-17, retinoic acid receptor-related orphan receptor C2 (RORC2), IL-23R, and IL-9 gene expression were measured using the quantitative reverse transcriptase-polymerase chain reaction. Count of lineage negative/CD127(+)/CD90(+) ILCs in the blood samples was performed by the flow cytometry method.
  
  
  RESULTS
  The transcript levels of IL-17 and RORC2 in CVID patients was strongly lower than control subjects (P = 0.049 and P = 0.046, respectively), but slight reduction in the IL-23R expression (P = 0.252) have seen in the CVID patients. Accordingly, the number of ILCs decreased significantly (P = 0.04). Interestingly, IL-9 mRNA level was more significantly in the CVID patients (P = 0.001).
  
  
  CONCLUSIONS
  The results presented in this study show that the Th17 cell specific genes expression (as the determiner Th17 cells) and ILCs (another lymphoid source of IL-17) are decreased in patients with CVID and this could be an explanation for the defect of their humoral immune response. In addition, elevation of the IL-9 gene expression may shed a new light into the way toward the understanding of the mechanism of autoimmunity in the CVID patients.
authors.affiliation: Cellular and Molecular Immunology Research Center, Isfahan University of Medical Sciences, Isfahan, Iran ; Department of Immunology, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Mazdak
authors.initials: M
authors.lastname: Ganjalikhani-Hakemi
authors.affiliation: Infectious Diseases and Tropical Medicine Research Center, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Reza
authors.initials: R
authors.lastname: Yazdani
authors.affiliation: Acquired Immunodeficiency Research Center, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Roya
authors.initials: R
authors.lastname: Sherkat
authors.affiliation: Department of Immunology, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Vida
authors.initials: V
authors.lastname: Homayouni
authors.affiliation: Department of Immunology, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Mohsen
authors.initials: M
authors.lastname: Masjedi
authors.affiliation: Department of Biostatistics and Epidemiology, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Mohsen
authors.initials: M
authors.lastname: Hosseini
keywords: Common variable immunodeficiency; T helper 17 cells; innate lymphoid cells; interleukin 17; interleukin 23R; interleukin 9