Alteration of the Salivary Secretory Proteome Profile in Adults Affected by Immune Deficiency Diseases

The acidic soluble fraction of the salivary proteome of 17 adult subjects affected by immune deficiency diseases was analysed by RP-HPLC-ESI-MS and compared with that of 17 sex- and age-matched healthy subjects. The qualitative and quantitative analysis of oral proteins and peptides was performed by a top-down label-free approach. The study evidenced a significant decrease of cystatin S, S1, S2, SN, SA, as well as of cystatin C, in the group of patients compared to controls. This result confirms a previous study in which a down regulation of protease inhibitors, including S-cystatins, was observed in saliva of subjects infected by human immunodeficiency virus type 1 (HIV-1) [1]. Therefore, the lower levels of S-type cystatins could be a signature of many immune diseases and could be involved in a reduction of the immune defenses. In contrast with the previous study, the up regulation of antimicrobial α-defensins was not observed in our patients. S100A proteins were differently affected by the immunodeficiency. In fact, S100A7 and S100A12 proteins showed a trend to increase, whereas the different S100A9 isoforms decreased in the patients with respect to the controls. Research is going on to confirm the relationship between the modification of the salivary proteome and immune deficiency diseases.