Low thymic output, peripheral homeostasis deregulation, and hastened regulatory T cells differentiation in children with 22q11.2 deletion syndrome.

OBJECTIVE: To perform an extensive analysis of the immune status of asymptomatic children with the 22q11.2 deletion syndrome, with special emphasis on the regulatory T cells (Treg) population. STUDY DESIGN: Analysis of thymic function, frequency and absolute counts of immune subsets, and phenotype of Treg were performed in 10 asymptomatic children bearing the 22q11.2 deletion and compared with 12 age-matched, healthy children. RESULTS: Children with 22q11.2 deletion syndrome showed a curtailed thymic output, lower T-cell levels, and a homeostatic deregulation in the CD4 T-cell compartment, characterized by a greater proliferative history in the naïve CD4 T-cell subset. Treg numbers were markedly reduced in children with 22q11.2 deletion syndrome, and remaining Treg showed mostly an activated phenotype. CONCLUSIONS: Reduced thymic output in children with 22q11.2 deletion syndrome could be related with an increased proliferation in the naïve CD4 T-cell compartment and the consequent Treg activation to ensure that T-cell expansion remains under control. Deregulated peripheral homeostasis and loss of suppressive capacity by Treg could compromise the integrity of T-cell immunity during adulthood and play a relevant role in the increased incidence of autoimmune diseases reported in patients with the 22q11.2 deletion syndrome.

Serum level of soluble vascular cell adhesion molecule in patients with hepatocellular carcinoma and its association with severity of liver disease.

BACKGROUND: VCAM-1 (soluble vascular cell adhesion molecule-1) plays a role in liver angiogenesis. Hepatocellular carcinoma (HCC) has important angiogenic activity, so expression of VCAM-1 may be pathogenic. AIM: To assess the association between serum VCAM-1 (sVCAM-1) levels and features of tumour and liver disease in patients with and without HCC, and to study the influence of HCC treatment on sVCAM-1 levels. MATERIAL AND METHODS: Concentrations in peripheral (sVCAM-1-P) and hepatic (sVCAM-1-H) veins were analysed using ELISA in 134 consecutive patients with chronic liver disease between May 2004 and February 2006, who underwent a splanchnic haemodynamic study. Of these patients, 58 had HCC. RESULTS: sVCAM-1-P and sVCAM-1-H were well correlated in both groups. No association was found between sVCAM-1-H and tumour features. No differences were observed in sVCAM-1-H between HCC and non-HCC cirrhotic patients. There was a significant linear association between Child-Pugh stage and sVCAM-1-H in HCC-patients (Child-Pugh A [2,485 ± 1,294 ng/mL] vs. Child-Pugh B [3,408 ± 1,338 ng/mL] vs. Child-Pugh C [4,096 ± 862 ng/mL]; p = 0.007). Seven non-cirrhotic HCC patients had a significantly lower sVCAM-1-H than cirrhotic HCC patients. Treatment of HCC leads to an increase in sVCAM-1-H levels although this was not associated with the necrosis response to treatment. CONCLUSIONS: sVCAM-1 levels are more closely associated with the severity of underlying liver disease than with the presence of HCC. sVCAM-1 levels are not associated with tumour features or invasiveness; therefore, sVCAM-1 does not seem to play an important role in the angiogenic processes of HCC.