A Possible Role for HSV-1-Specific Humoral Response and <i>PILRA</i> rs1859788 Polymorphism in the Pathogenesis of Parkinson’s Disease

• Main Authors: Simone Agostini, Roberta Mancuso, Andrea S. Costa, Lorenzo A. Citterio, Franca R. Guerini, Mario Meloni, Jorge Navarro, Mario Clerici
• Format: Article
• Language: English
• Published: MDPI AG 2021-06-01
• Series: Vaccines
• Subjects: Parkinson’s disease; HSV-1; paired immunoglobulin-like type 2 receptor alpha; antibody titers; rehabilitation
• Online Access: https://www.mdpi.com/2076-393X/9/7/686

The etiology of Parkinson’s disease (PD), a progressive nervous system disorder that affects movement, is still unknown; both genetic and environmental factor are believed to be involved in onset of the disease and its development. Herpes simplex virus type 1 (HSV-1), in particular, is suspected to have a role in PD. Paired Immunoglobulin-like type 2 receptor alpha (PILRA) is an inhibitory receptor that down-regulates inflammation and is expressed on innate immune cells. The <i>PILRA</i> rs1859788 polymorphism is protective against Alzheimer’s disease, even in relation with HSV-1 antibody titers, but no data are available in PD. We analyzed HSV-1 antibody titers and <i>PILRA</i> rs1859788 in PD (<i>n =</i> 51) and age-and sex-matched healthy controls (HC; <i>n =</i> 73). Results showed that HSV-1, but not cytomegalovirus (CMV) or human herpes virus type 6 (HHV-6) antibody titers were significantly higher in PD compared to HC (<i>p</i> = 0.045). The rs1859788 polymorphism was not differentially distributed between PD and HC, but the minor allele A was more frequently carried by PD (68%) compared to HC (50%) (<i>p</i> = 0.06). Notably, the rs1859788 minor allele A was statically more frequent in male PD (65%) compared to male HC (37%) (<i>p</i> = 0.036). Finally, no relation was found between HSV-1 antibody titers and <i>PILRA</i> genotype. Results herein suggest an involvement of HSV-1 in PD and indicate a possible interaction between <i>PILRA</i> gene polymorphisms and this neuropathology.