Antiadenohypophysis autoantibodies in patients with nongluten-related gastroenteropathies.

AIM: To investigate the presence of antipituitary antibodies (APA) in the serum of patients undergoing gastroenteropathies (GEP) other than celiac disease (CD). METHODS: APA were analyzed in GEP patients (n = 103), CD patients (n = 94), idiopathic growth hormone (GH) deficiency patients (n = 21), and 98 age- and sex-matched controls. Indirect immunofluorescence was performed in cryostat sections of baboon pituitary gland. RESULTS: APA were detected in 30% of GEP patients, 38% of them showed failure to thrive. No significant differences were found when we compared thrive impairment in negative and positive APA GEP patients. Indeed, normal values of insulin-like growth factor 1 were found in 93% of positive APA GEP patients. APA were detected in 52% of the CD patients. Ninety-one percent of them, in contrast to GEP group, showed significant growth impairment (P < 0.05) when compared to APA negative CD individuals. GH-deficient non-CD patients did not show APA. CONCLUSIONS: We have shown the presence of APA in patients with nongluten-related enteropathies. The presence of antipituitary autoantibodies in GEP patients does not seem to be associated with failure to thrive as it occurs in CD.

IL-17 producing T cells in celiac disease: angels or devils?

Celiac disease (CD) is a very common chronic condition in human beings, affecting approximately one in 100 individuals. It is an autoimmune disease with a defined environmental trigger, the gluten contained in dietary cereals, occurring in genetically susceptible individuals. The disease has a very strong HLA association. More than 90% of CD patients have HLA-DQ2, and almost all of the remaining celiac population possesses HLA-DQ8 molecules. Th17 cells seem to participate in the disease pathogenesis producing and secreting either proinflammatory or anti-inflammatory cytokines.

Interleukin-21 overexpression dominates T cell response to Epstein-Barr virus in a fatal case of X-linked lymphoproliferative syndrome type 1.

Interleukin-21 (IL-21) is a cytokine whose actions are closely related to B cell differentiation into plasma cells as well as to CD8(+) cytolytic T cell effector and memory generation, influencing the T lymphocyte response to different viruses. X-linked lymphoproliferative syndrome type 1 (XLP-1) is a primary immunodeficiency syndrome that is characterized by a high susceptibility to Epstein-Barr virus. We observed in a pediatric patient with XLP-1 that IL-21 was expressed in nearly all peripheral blood CD4(+) and CD8(+) T cells. However, IL-21 could not be found in the lymph nodes, suggesting massive mobilization of activated cells toward the infection's target organs, where IL-21-producing cells were detected, resulting in large areas of tissue damage.

A novel phenotype variant of severe congenital neutropenia caused by G6PC3 deficiency.

Severe congenital neutropenia type 4 (SCN4) is associated with mutations in the G6PC3 gene. To date, all patients bearing the p.Gly260Arg variant of the G6PC3 gene show heart defects. Here, we present a case of the p.Gly260Arg variant in a patient who did not have structural or functional heart anomalies. Treatment with granulocyte colony-stimulating factor recovered the absolute neutrophil count and neutrophil functional competence.

Characterization of gliadin-specific Th17 cells from the mucosa of celiac disease patients.

OBJECTIVES: Celiac disease (CD) is a disorder characterized by a deregulated immune response to ingested wheat gluten and related cereal proteins in susceptible individuals. It has been considered that the onset of CD is mediated by a skewed Th1 response. However, the participation of Th17 cells in the pathogenesis of the disease, a key cell population in other autoimmune disorders, has not been studied in detail. We have investigated the presence of Th17 cells in the mucosa of active CD patients and their functional implications in the pathogenesis of the disease. METHODS: T cells obtained from duodenum biopsies from 15 untreated patients and 11 control individuals were characterized by flow cytometry, immunoassays, and real-time PCR. RESULTS: We found gliadin-specific CD4(+) interleukin (IL)-17A-producing T cells in the mucosa of CD patients with a phenotype consisting of TCR (T-cell receptor)αß(+) CD45RO(+) CD161(+) CCR6(+) (C-C chemokine receptor type 6) and IL-23R(+). Functional analysis showed that Th17 cells from CD patients are different from those of control individuals in terms of cytokines production. Th17 cells from CD patients, but not from controls, simultaneously express transforming growth factor-ß (TGFß). Th17 CD cells also produce interferon-γ (IFNγ), IL-21, and IL-22. The analysis of the transcription factors revealed a high expression of interferon regulatory factor-4 as a feature of gliadin-specific cells from CD patients with respect to controls. CONCLUSIONS: Gliadin-specific Th17 cells are present in the mucosa of CD patients having a dual role in the pathogenesis of the disease as they produce proinflammatory cytokines (such as IL-17, IFNγ, IL-21), mucosa-protective IL-22, and regulatory TGFß, which actively modulates IL-17A production by T cells in the celiac mucosa.