A stabilized glycomimetic conjugate vaccine inducing protective antibodies against Neisseria meningitidis serogroup A
NATURE COMMUNICATIONS
Authors: Enotarpi, Jacopo; Tontini, Marta; Balocchi, Cristiana; van der Es, Daan; Auberger, Ludovic; Balducci, Evita; Carboni, Filippo; Proietti, Daniela; Casini, Daniele; Filippov, Dmitri, V; Overkleeft, Hermen S.; van der Marel, Gijsbert A.; Colombo, Cinzia; Romano, Maria Rosaria; Berti, Francesco; Costantino, Paolo; Codee, Jeroen D. C.; Lay, Luigi; Adamo, Roberto
Abstract
Neisseria meningitidis serogroup A capsular polysaccharide (MenA CPS) consists of (1 -> 6)-2-acetamido-2-deoxy-alpha-D-mannopyranosyl phosphate repeating units, O-acetylated at position C3 or C4. Glycomimetics appear attractive to overcome the CPS intrinsic lability in physiological media, due to cleavage of the phosphodiester bridge, and to develop a stable vaccine with longer shelf life in liquid formulation. Here, we generate a series of non-acetylated carbaMenA oligomers which are proven more stable than the CPS. An octamer (DP8) inhibits the binding of a MenA specific bactericidal mAb and polyclonal serum to the CPS, and is selected for further in vivo testing. However, its CRM197 conjugate raises murine antibodies towards the non-acetylated CPS backbone, but not the natural acetylated form. Accordingly, random O-acetylation of the DP8 is performed, resulting in a structure (Ac-carbaMenA) showing improved inhibition of anti-MenA CPS antibody binding and, after conjugation to CRM197, eliciting anti-MenA protective murine antibodies, comparably to the vaccine benchmark.
Quantitative proteomic analysis of rat retina with experimental autoimmune uveitis based on tandem mass tag (TMT) peptide labeling coupled with LC-MS/MS
JOURNAL OF CHROMATOGRAPHY B-ANALYTICAL TECHNOLOGIES IN THE BIOMEDICAL AND LIFE SCIENCES
Authors: Liu, Bin; Yin, Xuewei; Wei, Huixia; Wang, Zhe; Tang, Hongying; Qiu, Yan; Hao, Yixian; Zhang, Xiuyan; Bi, Hongsheng; Guo, Dadong
Abstract
Uveitis is a recurrent, inflammatory eye disease that occurs in the retina, iris, ciliary body and choroid. Currently, the detailed mechanism is still unclear. Proteomics can offer a powerful set of tools for the direct high-throughput study and a key contribution to the understanding of protein functions. This approach can also allow us to compare the protein profiling of the cells in healthy and diseased states that can be used to identify proteins associated with disease development and progression. In the present study, we first established an autoimmune uveitis (EAU) rat model. On day 12 after immunization, we isolated the rat retinas from both normal and EAU animals to collect total proteins. Using tandem mass tag (TMT) peptide labeling coupled with LC-MS/MS quantitative proteomics technique, we identified the differentially expressed proteins in EAU rat retinas, performed bioinformatics analyses, validated the expression of the COX1, NADH1, C3, and C9 proteins, and determined the adenosine triphosphate (ATP) levels. The results indicated that there were 190 upregulated and 103 downregulated proteins in EAU rat retinas. Bioinformatics analysis revealed the differentially expressed proteins were mainly involved in acute inflammatory response, visual perception and eye photoreceptor cell differentiation that were mainly related to complement and coagulation cascades, phagosome, PI3K-Akt signaling, and metabolic pathways. In conclusion, based on the TMT-based quantitative proteomics technique, the differentially expressed proteins in EAU rat retinas were mainly associated with complement and coagulation cascades and metabolic pathways. Our findings will facilitate the understanding of the pathogenesis of uveitis and will be useful for subsequent studies.