Effects of Complement Regulators and Chemokine Receptors in Type 2 Diabetes
IMMUNOLOGICAL INVESTIGATIONS
Authors: Ozgur, B. Aydin; Coskunpinar, E.; Gazioglu, S. Bilgic; Yilmaz, A.; Oltulu, Y. Musteri; Cakmakoglu, B.; Deniz, G.; Gurol, A. O.; Yilmaz, M. T.
Abstract
CD55 and CD59 are complement regulatory proteins suggested to be related with progression of diabetes and its complications. The stromal cell-derived factor 1 (SDF-1) and C-X-C chemokine receptor type 4 (CXCR-4) are chemokine proteins. We aimed to investigate the relation of CD55 and CD59 expression levels and polymorphisms of SDF-1 and CXCR-4 with type 2 diabetes mellitus (T2DM) and its complications. Seventy-five T2DM patients and 73 controls were enrolled. Expression levels of CD55 and CD59 were measured by FACS Calibur; qRT-PCR was used to determine SDF-1 and CXCR-4 gene polymorphisms. CD55 and CD59 expressions in patients with nephropathy, retinopathy and cardiovascular disease were significantly lower than controls. Frequency of CXCR-4 T allele carrying was high in patients and created 1.6 fold risk for the disease (p= .07). CXCR-4 a allele carriers had decreased nephropathy; although there was no statistical significance in carrying CXCR-4 T allele, presence of nephropathy was approximately 2 times higher (p= .254). The nephropathy risk increased 10-fold in CXCR-4 TT genotype carriers (p= .02). All SDF-1 CC genotype carriers had retinopathy, so, it was considered that the CC genotype was effective in retinopathy development (p= .031). For the presence of cardiovascular disease, significant difference was observed for SDF-1 genotypes. Increased cardiovascular risk of 5- and 1.9-fold in SDF-1 T (p= .007) and CXCR-4 T (p= .216) allele carriers, respectively, was observed. We suggest that CD55 and CD59 protein levels and SDF-1 and CXCR-4 have predictive importance in process, complications and tendency of T2DM.
Marked central nervous system pathology in CD59 knockout rats following passive transfer of Neuromyelitis optica immunoglobulin G
ACTA NEUROPATHOLOGICA COMMUNICATIONS
Authors: Yao, Xiaoming; Verkman, Alan S.
Abstract
Neuromyelitis optica spectrum disorders (herein called NMO) is an inflammatory demyelinating disease of the central nervous system in which pathogenesis involves complement-dependent cytotoxicity (CDC) produced by immunoglobulin G autoantibodies targeting aquaporin-4 (AQP4-IgG) on astrocytes. We reported evidence previously, using CD59(-/-) mice, that the membrane-associated complement inhibitor CD59 modulates CDC in NMO (Zhang and Verkman, J. Autoimmun. 53: 67-77, 2014). Motivated by the observation that rats, unlike mice, have human-like complement activity, here we generated CD59(-/-) rats to investigate the role of CD59 in NMO and to create NMO pathology by passive transfer of AQP4-IgG under conditions in which minimal pathology is produced in normal rats. CD59(-/-) rats generated by CRISPR/Cas9 technology showed no overt phenotype at baseline except for mild hemolysis. CDC assays in astrocyte cultures and cerebellar slices from CD59(-/-) rats showed much greater sensitivity to AQP4-IgG and complement than those from CD59(+/+) rats. Intracerebral administration of AQP4-IgG in CD59(-/-) rats produced marked NMO pathology, with astrocytopathy, inflammation, deposition of activated complement, and demyelination, whereas identically treated CD59+/+ rats showed minimal pathology. A single, intracisternal injection of AQP4-IgG in CD59(-/-) rats produced hindlimb paralysis by 3 days, with inflammation and deposition of activated complement in spinal cord, optic nerves and brain periventricular and surface matter, with most marked astrocyte injury in cervical spinal cord. These results implicate an important role of CD59 in modulating NMO pathology in rats and demonstrate amplification of AQP4-IgG-induced NMO disease with CD59 knockout.