Sequence variants of the TNFRSF13B gene in Czech CVID and IgAD patients in the context of other populations.

Mutations in the TNFRSF13B gene, encoding TACI, have been found in common variable immunodeficiency (CVID) and selective IgA deficient (IgAD) patients, but only the association with CVID seems to be significant. In this study, Czech CVID, IgAD and primary hypo/dysgammaglobulinemic (HG/DG) patients were screened for all TNFRSF13B sequence variants. The TNFRSF13B gene was mutated in 4/70 CVID patients (5.7%), 9/161 IgAD patients (5.6%), 1/17 HG/DG patient (5.9%) and none of 195 controls. Eight different mutations were detected, including the most frequent p.C104R and p.A181E mutations as well as 1 novel missense mutation, p.R189K. A significant association of TNFRSF13B gene mutations was observed in both CVID (p=0.01) and IgAD (p=0.002) Czech patients. However, when combined with all published data, only the association with CVID remained significant compared with the controls (9.9% vs. 3.2%, p<10(-6)), while statistical significance disappeared for IgAD (5.7% vs. 3.2%, p=0.145). The silent mutation p.P97P was shown to be associated significantly with CVID compared with the controls in both Czech patients (allele frequency 4.3% vs. 0.2%, p=0.01) and in connection with the published data (5.1% vs. 1.8%, p=0.003). The relevance of some TNFRSF13B gene variants remains unclear and needs to be elucidated in future studies.

Isoprinosine does not protect against frequent respiratory tract infections in childhood.

UNLABELLED: Isoprinosine, an in vitro immuno-enhancing agent principally acting by stimulating T-lymphocytes, is one of a number of agents sometimes used in an attempt to prevent recurrent respiratory infections in children, although there are no formal trials for this particular drug. We performed a placebo-controlled double-blind trial to assess the efficacy of isoprinosine (50 mg/kg per day) for 6 weeks followed by 50 mg/kg per day twice weekly for 6 weeks in the prevention of frequent acute respiratory tract infections in 102 children aged 4-8 years. A total of 43 children treated with isoprinosine and 41 with placebo finished the study. Despite a transient increase in the total number of CD3+, CD4+ and CD8+ T-lymphocytes after 6 weeks of daily isoprinosine treatment, there was no difference in the number and length of duration of acute respiratory infections, number of antibiotic courses and number of days with cough, pharyngitis, rhinitis and increased body temperature (> or = 37.0 degrees C and > or = 38.0 degrees C). There were no changes in markers of T- or B-lymphocyte activation (CD25, HLA-DR, CD45RA/RO, CD23). CONCLUSION: Attempts at immunomodulation using isoprinosine in the dose and for the duration used may increase the total numbers of both CD4 and CD8 T-lymphocytes but is ineffective in prevention of respiratory tract infections in childhood.