Elie Deeba1, Dana Koptides2, Anastasia Lambrianides3, Marios Pantzaris3, George Krashias4, Christina Christodoulou2. 1. Cyprus School of Molecular Medicine, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus. 2. Cyprus School of Molecular Medicine, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus; Department of Molecular Virology, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus. 3. Cyprus School of Molecular Medicine, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus; Neurology Clinic C, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus. 4. Cyprus School of Molecular Medicine, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus; Department of Molecular Virology, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus. Electronic address: georgek@cing.ac.cy.
Abstract
BACKGROUND: Multiple sclerosis (MS) is a chronic demyelinating disease of the central nervous system (CNS) where both environmental and genetic risk factors play a role. Among the environmental risk factors, EBV and HSV infections have been suggested as strong candidates contributing to MS pathology/progression. Viral recognition and control is largely tasked to the NK cells via TLR recognition and various cytotoxic and immunoregulatory functions. The present work aimed to characterize NK cells isolated from MS patients for genetic polymorphisms in the gene encoding for TLR3, as TLR3 in NK cells is important in herpesvirus recognition. METHODS: Highly purified NK cells isolated from peripheral blood of MS patients (n = 27) and healthy controls (n = 30) were used to sequence all five exons of the TLR3 gene using sanger sequencing. Alignment of the obtained sequences with the wild-type TLR3 sequence was used to identify genetic polymorphisms within the TLR3 gene. RESULTS: The alignment identified multiple substitution mutations across the five exons of the TLR3 gene (rs116729895, rs3775296, rs377529, rs3775290, rs3775291, rs376735334 and rs73873710). A significant difference was observed in the allele distribution of rs3775291 (Leu412Phe) between MS patients and HC, whereby the minor allele was detected in 38.9% of MS patients versus 11% of HC (Fisher's exact test, p = 0.021). CONCLUSION: There appears to be a possible association between the TLR3 missense mutation rs3775291 and multiple sclerosis, which might be attributed to changes in the TLR3 functional properties.
BACKGROUND:Multiple sclerosis (MS) is a chronic demyelinating disease of the central nervous system (CNS) where both environmental and genetic risk factors play a role. Among the environmental risk factors, EBV and HSV infections have been suggested as strong candidates contributing to MS pathology/progression. Viral recognition and control is largely tasked to the NK cells via TLR recognition and various cytotoxic and immunoregulatory functions. The present work aimed to characterize NK cells isolated from MSpatients for genetic polymorphisms in the gene encoding for TLR3, as TLR3 in NK cells is important in herpesvirus recognition. METHODS: Highly purified NK cells isolated from peripheral blood of MSpatients (n = 27) and healthy controls (n = 30) were used to sequence all five exons of the TLR3 gene using sanger sequencing. Alignment of the obtained sequences with the wild-type TLR3 sequence was used to identify genetic polymorphisms within the TLR3 gene. RESULTS: The alignment identified multiple substitution mutations across the five exons of the TLR3 gene (rs116729895, rs3775296, rs377529, rs3775290, rs3775291, rs376735334 and rs73873710). A significant difference was observed in the allele distribution of rs3775291 (Leu412Phe) between MSpatients and HC, whereby the minor allele was detected in 38.9% of MSpatients versus 11% of HC (Fisher's exact test, p = 0.021). CONCLUSION: There appears to be a possible association between the TLR3 missense mutation rs3775291 and multiple sclerosis, which might be attributed to changes in the TLR3 functional properties.