Only a few studies have reported abnormal T and B cell counts or abnormal distribution of T cell surface IgG-receptors [18,19].On the contrary, the study from Lopez-Lera et al. on the profiling of the RNA expression of peripheral blood mononuclear cells (PBMC) from C1-INH-HAE patients did not prove alterations in the expression pattern of PBMC in association with frequency and severity of disease [20]. This evidence concerns the gene SERPING1 and hereditary angioedema.