HLA-Cw allele frequencies in northern and southern Italy.

The evidence for HLA-Cw antigens' involvement in the modulation of the immune response in bone marrow transplantation, NK alloreactivity and the susceptibility and follow-up for different diseases has been growing in the recent years, but very few data on HLA-Cw distribution in healthy Italian subjects are available to date. This report presents an updated description of HLA-Cw frequencies in Italy, comparing data from the northern (Lombardia) and southern (Campania and Puglia) parts of the country. A total of 1101 healthy subjects of Italian origin were genotyped, and the results showed that HLA-Cw*04, Cw*07, Cw*12, and, in particular, Cw*0401, Cw*0701, Cw*1203, were the most frequent alleles found in all three regions analysed. Nevertheless, statistically significant differences were observed in Cw*07 distribution, which was more frequent in the southern than in the northern part of Italy (28.8% vs 22.4%; p=0.001; OR: 1.4; 95%CI: 1.14-1.73), and in Cw*12 distribution, which was more frequent in the north than the south (17.0% vs 12.4%; p=0.007, OR: 1.4; 95%CI: 1.10-1.91). These results, which give an improved pattern of distribution of HLA-Cw alleles in the Italian population, would be useful in bone marrow transplantation and anthropological studies. Moreover, due to the important role of HLA-Cw antigens in modulation of the immune response and NK alloreactivity, these data would be of interest in studies on susceptibility, follow-up and/or protection against different diseases.

KIRs and their HLA ligands in remitting-relapsing multiple sclerosis.

Killer Immunoglobulin-like Receptor (KIR) genes may affect both resistance and susceptibility to autoimmune disorders, but their role in the pathogenesis of Multiple Sclerosis (MS) is still unclear. To evaluate the involvement of KIRs and their HLA ligands in the development of MS we performed genotyping of HLA -A, -B, -Cw, -DRB1 and KIRs loci in 121 RRMS patients and 103 healthy controls (HC). Results evidenced a possible protective role of the activating KIR2DS1 gene (p(y)=0.001; OR:0.38), enhanced in the presence of its ligand group HLA-C2 (p(y)=0.0001; OR:0.23). Our data suggest that the presence of functional compounds of activating KIR receptors together with their HLA ligands, allowing the immunomodulatory function of NK cells, may have a protective role against the disease.