[4D-DIA proteomics reveals mechanism of Sanpian Decoction in treating chronic migraine in rats].

To explore the mechanism of the classic formula Sanpian Decoction in treating chronic migraine, this study employed the four-dimensional data-dependent acquisition(4D-DIA) proteomics to analyze the effect of the decoction on chronic migraine in rats and experimentally verified the key differentially expressed proteins. Firstly, SD male rats were randomly divided into groups and repeatedly injected with nitroglycerin to prepare a chronic migraine model. After 7 consecutive days of gavage, rat grimace scale(RGS) was employed to evaluate the treatment efficacy. The trigeminal ganglion was collected for 4D-DIA proteomics, on the basis of which the diffe-rentially expressed proteins between groups were screened. Multiple databases were used for the Gene Ontology(GO) and Kyoto Encyclopedia of Genes and Genomes(KEGG) enrichment of the differentially expressed proteins. STRING and Cytoscape were employed to establish the protein-protein interaction(PPI) network. Western blot was employed to determine the expression level of the key diffe-rentially expressed protein TRPV1. The results showed that there were 517 differentially expressed proteins between blank group and model group and 221 differentially expressed proteins between model group and medium-dose Sanpian Decoction group. The GO and KEGG enrichment results showed that these differentially expressed proteins were mainly related to inflammatory response, injurious sensory stimulation, triglyceride metabolism, immune regulation, etc., which mainly involved the inflammation-related TRP, AMPK, PI3K-Akt, and TGF-ß signaling pathways. The PPI network showed that the target proteins such as IGF, TOP2A, APOA1, CDK1, TTN, RYR1, and CSRP3 had high degrees. Compared with that in model group, the expression level of TRPV1 altered in medium-and high-dose Sanpian Decoction group(P<0.05). In conclusion, Sanpian Decoction may treat chronic migraine by regulating the inflammation-related pathways such as TRP, AMPK, and PI3K-Akt. It plays an important role in the regulation of TRPV1 protein and potentially modulates the perception of injurious stimuli, lipid metabolism, and immune responses.

Mosaic quadrivalent influenza vaccine single nanoparticle characterization.

Recent work by our laboratory and others indicates that co-display of multiple antigens on protein-based nanoparticles may be key to induce cross-reactive antibodies that provide broad protection against disease. To reach the ultimate goal of a universal vaccine for seasonal influenza, a mosaic influenza nanoparticle vaccine (FluMos-v1) was developed for clinical trial (NCT04896086). FluMos-v1 is unique in that it is designed to co-display four recently circulating haemagglutinin (HA) strains; however, current vaccine analysis techniques are limited to nanoparticle population analysis, thus, are unable to determine the valency of an individual nanoparticle. For the first time, we demonstrate by total internal reflection fluorescence microscopy and supportive physical-chemical methods that the co-display of four antigens is indeed achieved in single nanoparticles. Additionally, we have determined percentages of multivalent (mosaic) nanoparticles with four, three, or two HA proteins. The integrated imaging and physicochemical methods we have developed for single nanoparticle multivalency will serve to further understand immunogenicity data from our current FluMos-v1 clinical trial.

N-doped carbon dots coupled with molecularly imprinted polymers as a fluorescent sensor for ultrasensitive detection of genistein in soya products.

Rapid detection of genistein in soya products has remained difficult. Current methods necessitate sample handling and use of costly instruments. Here, using a simple one-pot reverse microemulsion method, a sensor based on N-doped carbon dots conjugated molecularly imprinted polymers (N-CDs@MIPs) was synthesized to analyze genistein. N-doped carbon dots were used as fluorescent component, genistein as the template molecule, and molecularly imprinted polymers as the selective sorbent in this fluorescence sensor. The sensor was then examined and optical studies demonstrated that N-CDs@MIPs not only had strong fluorescence emission and outstanding optical stability, but also had good sensitivity (detection limit 35.7 nM) and selectivity to genistein. Furthermore, the N-CDs@MIPs materials were used to analyze genistein in soya products, and the findings (which ranged from 99.77% to 106.11%) show that the N-CDs@MIPs has high potential for quickly detecting the amount of genistein in complicated food samples.

Bispecific antibody CAP256.J3LS targets V2-apex and CD4-binding sites with high breadth and potency.

Antibody CAP256-VRC26.25 targets the second hypervariable region (V2) at the apex of the HIV envelope (Env) trimer with extraordinary neutralization potency, although less than optimal breadth. To improve breadth, we linked the light chain of CAP256V2LS, an optimized version of CAP256-VRC26.25 currently under clinical evaluation, to the llama nanobody J3, which has broad CD4-binding site-directed neutralization. The J3-linked bispecific antibody exhibited improved breadth and potency over both J3 and CAP256V2LS, indicative of synergistic neutralization. The cryo-EM structure of the bispecific antibody in complex with a prefusion-closed Env trimer revealed simultaneous binding of J3 and CAP256V2LS. We further optimized the pharmacokinetics of the bispecific antibody by reducing the net positive charge of J3. The optimized bispecific antibody, which we named CAP256.J3LS, had a half-life similar to CAP256V2LS in human FcRn knock-in mice and exhibited suitable auto-reactivity, manufacturability, and biophysical risk. CAP256.J3LS neutralized over 97% of a multiclade 208-strain panel (geometric mean concentration for 80% inhibition (IC80) 0.079 µg/ml) and 100% of a 100-virus clade C panel (geometric mean IC80 of 0.05 µg/ml), suggesting its anti-HIV utility especially in regions where clade C dominates.

Does living at high altitude increase the risk of bleeding events after total knee arthroplasty? A retrospective cohort study.

OBJECTIVE: Post-operative bleeding after total knee arthroplasty (TKA) is a frequent cause of post-operative complications. This study compared blood loss and indicators of coagulation and fibrinolysis between TKA patients living at low or high altitudes. METHODS: We retrospectively analyzed 120 patients at our institution who underwent primary TKA from May 2019 to March 2020, and we divided them into those living in areas about 500 m or > 3000 m above sea level. We compared the primary outcome of total blood loss between them. We also compared them in terms of several secondary outcomes: coagulation and fibrinolysis parameters, platelet count, reduction in hemoglobin, hidden blood loss, intra-operative blood loss, transfusion rate, and incidence of thromboembolic events and other complications. RESULTS: Total blood loss was significantly higher in the high-altitude group than in the low-altitude group (mean, 748.2 mL [95% CI, 658.5-837.9] vs 556.6 mL [95% CI, 496.0-617.1]; p = 0.001). The high-altitude group also showed significantly longer activated partial thromboplastin time, prothrombin time, and thrombin time before surgery and on post-operative day one, as well as increased levels of fibrinogen/fibrin degradation product on post-operative days one and three. Ecchymosis was significantly more frequent in the high-altitude group (41.7 vs 21.7%; relative risk (RR) = 1.923 [95% CI, 1.091-3.389]; p = 0.019). The two groups showed similar transfusion rates, and none of the patients experienced venous thromboembolism, pulmonary embolism, or infection. CONCLUSION: High altitude may alter coagulation and fibrinolysis parameters in a way that increases risk of blood loss after TKA. Such patients may benefit from special management to avoid bleeding events.

Analytical characterization of broadly neutralizing antibody CAP256LS heavy chain clipping during manufacturing development.

Broadly neutralizing antibody (bNAb) CAP256-VRC26.25 (abbreviated CAP256LS), a human IgGI monoclonal antibody targeting the V1V2 site of the HIV-1 envelope, has demonstrated high therapeutic potential as a broadly neutralizing monoclonal antibody against HIV-1. During the process development, a heavy chain fragmentation (clipping) was observed, that led to a relative potency reduction. In this report, we highlighted a series of process and product mitigation strategies deployed to advance this product. We have detailed how analytical characterization tools, especially the microchip reduced capillary gel electrophoresis (CGE-SDS), played a pivotal role in identifying the development issues and in providing measurements to guide implementation of mitigation strategies.

Tyrosine O-sulfation proteoforms affect HIV-1 monoclonal antibody potency.

CAP256V2LS, a broadly neutralizing monoclonal antibody (bNAb), is being pursued as a promising drug for HIV-1 prevention. The total level of tyrosine-O-sulfation, a post-translational modification, was known to play a key role for antibody biological activity. More importantly, here wedescribe for the first time the significance of the tyrosine-O-sulfation proteoforms. We developed a hydrophobic interaction chromatography (HIC) method to separate and quantify different sulfation proteoforms, which led to the direct functionality assessment of tyrosine-sulfated species. The fully sulfated (4-SO3) proteoform demonstrated the highest in vitro relative antigen binding potency and neutralization efficiency against a panel of HIV-1 viruses. Interestingly, highly variable levels of 4-SO3 were produced by different clonal CHO cell lines, which helped the bNAb process development towards production of a highly potent CAP256V2LS clinical product with high 4-SO3 proteoform. This study presents powerful insight for any biotherapeutic protein development where sulfation may play an important role in product efficacy.

Controlling anisotropic thermal properties of graphene aerogel by compressive strain.

Materials with adjustable wide-ranging thermal conductivity are desired to tackle the problem of thermal management for electronic devices operating in an extended range of temperature. In this study, graphene aerogels (GAs) are fabricated and transformed from thermal insulators to thermal conductors by high-temperature annealing. The highest through-plane and in-plane thermal conductivity of annealed GA reaches 3.3 and 96 W/m·K, respectively, under 95% compressive strain. Using the annealed GA as thermal interface material leads to superior performance than commercially available products that have higher through-plane thermal conductivity in dissipating heat for high-power electronic devices (e.g., LED lamp). Furthermore, due to excellent elasticity, the thermal resistance of annealed GAs can be reversibly tuned about six-fold by compressive strain. This paves a novel venue in designing thermal management system for devices, which not only need excellent heat dissipation but also good thermal insulation at various operating environments.

Development and application of an analytical approach to assess an antibody's potential for disulfide reduction.

Monoclonal antibody (mAb) interchain disulfide bond reduction has been observed in a recent large-scale clinical manufacturing operation. A massive reduction/precipitation at post-clarification steps has occurred. This note presents the development of a novel analytical approach to identify the "potential reduction"-a unique approach to predict the propensity of a monomeric-profiled mAb to be reduced in the post-harvest stage, such as harvest clarification and/or purification steps. The core of this new approach includes comparing the non-reducing capillary electrophoresis profiles of pre- and post-vacuum treated mAb in harvest cell culture fluid (HCCF). Using this approach, the potential reductions of two in-house mAbs in the unclarified and clarified cell culture harvest were assessed.

Free-standing graphene aerogel with improved through-plane thermal conductivity after being annealed at high temperature.

Both high through-plane thermal conductivity and low elastic modulus can reduce thermal interface resistance, which is important for thermal interface materials. The internal porous structure of graphene aerogel (GA) makes it to have a low elastic modulus, which results in its good compressibility. Also, the network structure of GA provides thermal conducting paths, which improve the through-plane thermal conductivity of GA. Annealing GA at 3000 °C helps to remove oxygen-containing functional groups and reduces defects. This greatly improves its crystallinity, which further leads to the improvement of its through-plane thermal conductivity and it has a low modulus of 1.37Mpa. The through-plane thermal conductivity of GA annealed at 3000 °C (GA-3000) was improved as the pressure increased and got to 2.93 W/ m K at a pressure of 1.13 MPa, which is 30 times higher than other graphene-based thermal interface materials (TIMs). These discoveries offer a novel approach for preparing excellent TIMs.

Structures of HIV-1 Neutralizing Antibody 10E8 Delineate the Mechanistic Basis of Its Multi-Peak Behavior on Size-Exclusion Chromatography.

Antibody 10E8 is capable of effectively neutralizing HIV through its recognition of the membrane-proximal external region (MPER), and a suitably optimized version of 10E8 might have utility in HIV therapy and prophylaxis. However, 10E8 displays a three-peak profile on size-exclusion chromatography (SEC), complicating its manufacture. Here we show cis-trans conformational isomerization of the Tyr-Pro-Pro (YPP) motif in the heavy chain 3rd complementarity-determining region (CDR H3) of antibody 10E8 to be the mechanistic basis of its multipeak behavior. We observed 10E8 to undergo slow conformational isomerization and delineate a mechanistic explanation for effective comodifiers that were able to resolve its SEC heterogeneity and to allow an evaluation of the critical quality attribute of aggregation. We determined crystal structures of single and double alanine mutants of a key di-proline motif and of a light chain variant, revealing alternative conformations of the CDR H3. We also replicated both multi-peak and delayed SEC behavior with MPER-antibodies 4E10 and VRC42, by introducing a Tyr-Pro (YP) motif into their CDR H3s. Our results show how a conformationally dynamic CDR H3 can provide the requisite structural plasticity needed for a highly hydrophobic paratope to recognize its membrane-proximal epitope.

Protein and glycan molecular weight determination of highly glycosylated HIV-1 envelope trimers by HPSEC-MALS.

High Performance Size-Exclusion Chromatography coupled with Multi-Angle Light Scattering detection (HPSEC-MALS) is an important tool to provide a reliable molecular weight measurement for a large complex biomolecule. A recent HIV-1 soluble envelope trimer vaccine candidate, BG505 DS-SOSIP.664, is among the most glycosylated proteins to enter a clinical trial to date, and determination of its protein and glycan molecular weight is one of the key attributes in pre-clinical characterization. However, protein and glycans possess disparate dndcvalues making molecular weight measurement inaccurate in conventional SEC-MALS. To overcome these challenges, a simple mathematically guided experiment was explored, and a composite dndcvalue was established by utilizing protein and glycan mass contributions for the HIV-1 envelope trimer. This establishment was further verified by an orthogonal mass spectrometry analysis. This innovative, simple, and quick analytical approach can be applied broadly to measuring the molecular weight of various composite molecular structures, such as complex glycoconjugates.

Quantitative source apportionment, risk assessment and distribution of heavy metals in agricultural soils from southern Shandong Peninsula of China.

The heavy metals, including cadmium (Cd), chromium (Cr), copper (Cu), mercury (Hg), nickel (Ni), lead (Pb), zinc (Zn), and the metalloid arsenic (As) were detected in surface and core soil samples collected from a tobacco growing region in Shandong Peninsula on the east coast of China to evaluate their pollution levels, ecological and health risks, and to analyze their spatial and vertical distributions. The heavy metal sources were identified quantitatively using the positive matrix factorization (PMF) receptor model. In accordance, most of the soils did not have accumulations and were not contaminated by As, Cr, Cu, Ni, Pb, and Zn. High accumulations of Cd and Hg occurred in the soils, posing an ecological risk to the local agricultural environment, while Cr and Ni levels presented a carcinogenic health risk to humans. Four main sources of heavy metals in the soils were identified. Correspondingly Ni and Cr were mainly originated from natural sources, Hg from coal combustion, Cd from agricultural practices, Cu, Pb, and Zn from agricultural practices and industrial activities, and As from industrial activities.

A unique algorithm for the determination of peptide-carrier protein conjugation ratio by amino acid analysis using intrinsic internal standard.

An N-terminal peptide of the HIV-1 fusion peptide (FP) with eight amino acid residues (FP8) was conjugated to a recombinant Tetanus Toxoid Heavy Chain Fragment C (rTTHc) as a carrier protein to help boosting immunogenicity against HIV-1. In this rapid communication, a unique algorithm to determine FP-rTTHc conjugation ratio was developed based off the amino acid analysis. Five well recovered amino acids (present in both FP and rTTHc) were used to calculate the conjugation ratio, while proline (present only in rTTHc) was identified and utilized as the intrinsic internal standard for normalization. With this calculation, the assay variability was minimized (<20%), especially for conjugates with moderate to low conjugation ratios as being compared to previously reported methods. The approach offers a reliable tool to determine the efficiency of the conjugation reactions for in-process monitoring and for final conjugate product characterization.

Development of a New Tandem Ion Exchange and Size Exclusion Chromatography Method To Monitor Vaccine Particle Titer in Cell Culture Media.

A new tandem chromatography method was developed to directly measure the titers of various vaccine candidate molecules in cell culture without a prior purification step. The method utilized a strong anion exchange chromatography (IEC) column in tandem with a size exclusion chromatography (SEC) column to efficiently separate the nanoparticle and virus-like particle (VLP) vaccine molecules from host cell proteins and other components in the cell culture media. The dual (charge and hydrodynamic size) separation mode was deemed necessary to achieve good separation of the vaccine product for quantitation. The method development and quality assessment illustrated herein was focused on the influenza vaccine candidate H1ssF, a hemagglutinin (group 1) stabilized stem molecule fused to ferritin to form nanoparticles. This newly established method was then successfully applied to several vaccine candidate developmental projects, such as the hemagglutinin-ferritin (HAF) nanoparticle and encephalitic alphavirus VLP-based vaccines. This IEC-SEC strategy was established as a platform approach for direct titer measurement of novel vaccine molecules in cell culture.

Overcoming the Multiple-Monomeric-Peak Profile of Broadly Neutralizing HIV-1 Antibody 10E8 with a Unique Size-Exclusion-Chromatography Method.

10E8 is a potent broadly neutralizing antibody (bNAb) that targets the membrane-proximal external region (MPER) of the HIV virus. During early analytical development of this bNAb directed towards clinical evaluation, 10E8 exhibited a multiple-monomeric-peak profile caused by secondary interactions in traditional size-exclusion chromatography (SEC), thereby rendering SEC unfit for the purpose of assessing aggregation, a target critical quality attribute. To overcome this challenge, an innovative and robust SEC method was successfully developed in which the mobile phase was tested for excipients capable of reducing the secondary interactions responsible for the multipeak profile, and an optimal mobile phase composed of 2× PBS and 100 mM arginine at pH 10.55 was established. Application of this optimized mobile phase was shown to allow quantification of the intrinsic level of aggregation of 10E8 without alteration to the SEC matrix itself. Furthermore, the newly developed method was linear, specific, accurate, and precise over an established range. Overall, an SEC method involving optimization of the mobile phase has been successfully developed, which allowed for assessment of antibody aggregation throughout process development, manufacturing, release, and stability testing.

Multiple resonant scattering of water waves by a two-dimensional array of vertical cylinders: linear aspects.

We study the Bragg resonance of surface water waves by a two-dimensional array of vertical cylinders covering a large area of the sea. Starting from the resonance criterion known in the physics of solid state and crystallography, we employ asymptotic techniques to derive two-dimensional coupled-mode equations for the envelopes of scattered waves resonated by a plane incident wave. Explicit analytical solutions are obtained for a long strip of cylinder array which may be used for supporting a future offshore airport. Examples of both two-wave and three-wave resonances are discussed in detail. Roles of the band gaps are examined.

Evolution of solitons over a randomly rough seabed.

For long waves propagating over a randomly uneven seabed, we derive a modified Korteweg-de Vries (KdV) equation including new terms representing the effects of disorder on amplitude attenuation and wave phase. Analytical and numerical results are described for the evolution of a soliton entering a semi-infinite region of disorder, and the fission of new solitons after passing over a finite region of disorder.