Increased Horizontal Transmission of Recombinant Marek's Disease Virus Due to Reticuloendotheliosis Virus Long Terminal Repeat Is the Major Competitive Advantage of the Virus Being a Prevalent Strain.

GX0101 is the first field Marek's disease virus (MDV) recombinant with an REV LTR insert isolated in China. We speculated that there was a selective advantage of GX0101 becoming the more prevalent field strain from a very low percentage of recombinant virus. In the study, dual fluorescence quantitative real-time PCR (DF-qPCR) that detects GX0101 and GX0101ΔLTR simultaneously was established based on the genomic difference of GX0101 and its LTR deletion strain GX0101ΔLTR. MDV natural transmission was simulated in specific-pathogen-free (SPF) chicks, and continuous tracking of GX0101 and GX0101ΔLTR in chicks was carried out. The results showed that GX0101 possessed high horizontal transmission capacity, which could infect SPF chicks by contact in a short time and became the predominant strain following contact infections in chicken flocks. GX0101 still had a more significant advantage of horizontal transmission than GX0101ΔLTR after continuous passage even if the initially infectious dose was significantly lower. There were 72 differentially expressed MDV genes between GX0101 and GX0101ΔLTR, with the genes and gene products mainly involved in virus replication, tegument protein, glycoprotein, nucleocapsid protein, immune evasion, tumor development and/or pathogenesis, and hypothetical protein. Sixteen genes related to virus replication and transmission were significantly up-regulated. This is the first study to illuminate that increased horizontal transmission of recombinant MDV due to REV LTR was the competitive advantage of the virus being a prevalent strain and define the differential transcription profile of viral genes between GX0101 and GX0101ΔLTR. This will be helpful for in-depth study on the molecular mechanism of increased horizontal transmission of MDV by REV LTR.

Therapeutic vaccine against IL-1ß improved glucose control in a mouse model of type 2 diabetes.

AIMS: Inflammation is strongly associated with the mechanism of ß-cell failure in type 2 diabetes mellitus (T2DM). Blockade of the key proinflammatory cytokine IL-1ß has been implicated as a promising therapeutic strategy for the prevention and treatment of type 2 diabetes. In this study, we developed an IL-1ß-targeted therapeutic vaccine consisting of an IL-1ß epitope peptide (A1ß) and assessed its efficacy on a diabetic KK-Ay mouse model. MAIN METHODS: KK-Ay mice were immunized with A1ß for three injections at a 2-week interval. The induced antibody titers, body weights and blood glucose levels were monitored every two weeks. Then the intraperitoneal glucose tolerance test and insulin tolerance test were performed. The ß-cell mass, ß-cell apoptosis and proliferation were evaluated by immunofluorescence. IL-1ß gene expression in islets was also measured by quantitative RT-PCR. KEY FINDINGS: A1ß immunization induced robust antibody responses, reduced body weight gain, improved glucose tolerance and insulin sensitivity in KK-Ay mice. Moreover, A1ß restored ß-cell mass, inhibited ß-cell apoptosis, enhanced ß-cell proliferation and downregulated IL-1ß expression. SIGNIFICANCE: The novel IL-1ß-targeted epitope vaccine has the therapeutic potential for T2DM.

Intravenous immunoglobulin improves glucose control and ß-cell function in human IAPP transgenic mice by attenuating islet inflammation and reducing IAPP oligomers.

Type 2 diabetes mellitus (T2DM) is a metabolic disorder characterized by ß-cell loss, insulin resistance, islet inflammation and amyloid deposits derived from islet amyloid polypeptide (IAPP). Reducing toxic IAPP oligomers and inhibiting islet inflammation may provide therapeutic benefit in treating T2DM. Intravenous immunoglobulin (IVIg) is an efficient anti-inflammatory and immunomodulatory agent for the treatment of several autoimmune or inflammatory neurological diseases. However, whether IVIg has therapeutic potential on T2DM remains unclear. In present study, we showed that IVIg treatment significantly improved glucose control and insulin sensitivity, and prevented ß-cell apoptosis by lowering toxic IAPP oligomer levels, attenuating islet inflammation and activating autophagy in human IAPP transgenic mouse model. These results suggest that IVIg is a promising therapeutic potential for T2DM treatment.