Quantitative assessment of the breast cancer marker HER2 using a gold nanoparticle-based lateral flow immunoassay

Human epidermal growth factor receptor 2(HER2)is an important biomarker for detection and treatment of breast cancer.In this study,we developed monoclonal antibodies against the extracellular domain(ECD)of HER2 and established a rapid and accurate lateral flow immunoassay(LFIA)for use in community medical institutions.The gene sequence of human HER2-ECD was obtained from the National Center for Biotechnology Information(NCBI)to construct the expression plasmid.HER2-ECD protein expressed in HEK293F cells was used to immunize BALB/c mice.The monoclonal antibodies were produced in mouse ascites and isolated by hybridoma cell screening.Antibodies were analyzed for purity by SDS-PAGE(sodium dodecyl sulphate-polyacrylamide gel-electrophoresis)and affinity was assessed by enzyme-linked immunosorbent assay(ELISA)while subtypes were detected using the commercial kits.The HER2-ECD test strip was prepared based on the sandwich method and evaluated using a portable detection instrument.The affinity of the paired antibodies,4D8 and 8D9,both reached 1×108 L/mol.Both antibodies specifically recognized the HER2-ECD protein in serum.The limit of detection(LOD)of the gold nanoparticle(AuNP)-based LFIA was 1.7 ng/mL with a detection range of 1.7-400 ng/mL,and the performance of the HER2-ECD strip correlated well with that of a Siemens chemiluminescent immunoassay(CLIA)kit.In conclusion,the paired antibodies were successfully prepared with high affinity and specificity.The AuNP-based LFIA of HER2-ECD provides a fast and accurate method to detect the concentration of HER2-ECD in serum samples for clinical use in community medical institutions,and could contribute to determining the progress of the disease or the effectiveness of treatment.

Electromagnetic field-enhanced chiral dimanganese trioxide nanoparticles mitigate Parkinson’s disease

The misfolding and aggregation ofα-synuclein(α-syn)is closely associated with Parkinson’s disease(PD).Here,chiral dimanganese trioxide(Mn_(2)O_(3))nanoparticles(NPs)were prepared for PD treatment enhanced by a noninvasive electromagnetic field(MF).The affinity constants of D-NPs towardα-syn monomer(mono)orα-syn fibril were 3.5 times or 5.2 times higher,respectively,than those of L-NPs,and the mechanical force generated by NPs under a MF further promoted the interaction between NPs andα-syn to amplify the difference between L-NPs and D-NPs.As the synergy effect of the preferentially affinity ability and MF-induced mechanical forces,D-NPs exhibited a better inhibitory efficiency onα-syn fibrillization than L-NPs.Furthermore,after differentially cellular uptake of L-/D-NPs via the caveolin-mediated pathway,as reactive oxygen species(ROS)-scavengers,D-NPs possess higher efficiency in decreasing intracellular ROS level than L-NPs to provide higher cytoprotective efficiency to neuron cells.In vivo data showed that after treatment with D-NPs under a MF for 60 days,α-syn concentration in the cerebrospinal fluid of PD mice decreased 81%,while dopamine level in the brain of PD mice increased 2.3-fold.These findings indicated the potential of utilizing the synergic interplay of chiral NPs and MF for treating disease and opened a new path to explore the nanoscale chirality for regulating the biological effect.

Chiral Cu_(x)Co_(y)S Supraparticles Ameliorate Parkinson’s Disease

Protein aggregation causes alpha-synuclein(α-syn)to change from its original physiological role to a pathological state,which is a potential pathogenic mechanism in Parkinson’s disease(PD).Chiral _(L/D)-Cu_(x)Co_(y)S supraparticles(_(L/D)-SPs)with a circular dichroism value of 35 mdeg at 805 nm were fabricated using a simple wet-chemical method.The _(L/D)-SPs prevented the α-syn monomers from forming fibrils and triggered the α-syn fibrils to turn into monomers under 808 nm near-infrared(NIR)light.In living MN9D cells,D-SPs reduced cellular damage,neuronal functional deficits,and neuron loss caused by α-syn fibrils after NIR spectroscopy treatment within 10 min to prevent α-syn aggregation.Significantly,the reactive oxygen species produced by _(D)-SPs were 1.42 times higher than those produced by _(L)-SPs.In vivo experiments showed that _(D)-SPs had a protective effect on neuron damage caused by α-syn aggregate deposition,reduced the symptoms in a mouse model of PD,and restored cognitive ability.After NIR light treatment,the amount of α-syn in a mouse model of PD decreased by more than 67.5%.At the same time,_(D)-SPs gradually decomposed into small nanoparticleswithin 60 days and were excreted through the blood-brain barrier.This discovery paves theway for the treatment of neurodegenerative diseases using chiral SPs under NIR light irradiation.