Fragment Antigen Research Articles

Effects of Bevacizumab Combined with Chemotherapy on CT, CyFRA21-1, and ProGRP and Prognosis of Lung Cancer Patients under Nursing Intervention.

Objective Molecular targeted drug therapy and chemotherapy are the main treatments for advanced non-small-cell lung cancer, and the combination of both has advantages in prolonging patients' progression-free survival and overall survival. This study investigated the effects of bevacizumab combined with chemotherapy under nursing intervention on CT, cytokeratin 19 fragment antigen 21-1 (CYFRA21-1), and gastrin-releasing peptide precursor (ProGRP) and prognosis of lung cancer patients. Methods 102 patients with non-small-cell lung cancer admitted to our hospital from January 2018 to May 2019 were divided into observation group and control group, with 51 cases each. The control group was treated with basic chemotherapy, and the observation group was treated with bevacizumab in combination with the control group, and both groups used nursing interventions. The clinical effects, CYFRA21-1 and ProGRP levels, baseline data, CT parameters, 24-month cumulative survival, and the effects of CYFRA21-1 and ProGRP on long-term survival and lung function were compared. Results The disease control rate of the observation group was 94.12%, which was significantly higher than that of the control group (76.47%); after 7 d, 30 d, 60 d, and 90 d of treatment, the levels of CYFRA21-1 and ProGRP were statistically downregulated. The difference in lymph node metastasis, lesion diameter, plain Eff-Z, venous stage, and arterial stage normalized iodine concentrations (NIC) was statistically significant; the survival rate at 24 months in the observation group was 74.51% (38/51); the cumulative survival rate at 24 months in the control group was 52.94% (27/51), and the difference was statistically significant (X2 = 4.980, P = 0.026). The cumulative survival rate at 24 months was significantly lower in patients with high expression of CYFRA21-1 and ProGRP compared with those with low expression of CYFRA21-1 and ProGRP. After treatment, in the observation group, the forceful spirometry (FVC), forceful expiratory volume in one second (FEV1), and FEV1/FVC levels were significantly different from those before treatment and were significantly different from those in the control group. Conclusion Bevacizumab in combination with standard chemotherapy regimens with nursing interventions could benefit patients with advanced non-small-cell lung cancer and had a good prospect of application.

Exploiting Meltable Protein Hydrogels to Encapsulate and Culture Cells in 3D.

There is a growing realization that 3D cell culture better mimics complex in vivo environments than 2D, lessening aberrant cellular behaviors and ultimately improving the outcomes of experiments. Chemically crosslinked hydrogels which imitate natural extracellular matrix (ECM) are proven cell culture platforms, but the encapsulation of cells within these hydrogel networks requires bioorthogonal crosslinking chemistries which can be cytotoxic, synthetically demanding, and costly. Capsular antigen fragment 1 (Caf1) is a bacterial, polymeric, fimbrial protein which can be genetically engineered to imitate ECM. Furthermore, it can, reversibly, thermally interconvert between its polymeric and monomeric forms even when chemically crosslinked within a hydrogel network. It is demonstrated that this meltable feature of Caf1 hydrogels can be utilized to encapsulate neonatal human dermal fibroblasts at a range of cell densities (2×105 -2×106 cellsmL-1 of hydrogel) avoiding issues with chemical cytotoxicity. These hydrogels supported cell 3D culture for up to 21d, successfully inducing cellular functions such as proliferation and migration. This work is significant because it further highlights the potential of simple, robust, Caf1-based hydrogels as a cell culture platform.

Prognostic Evaluation of CT Imaging Big Data-Assisted Arterial Chemoembolization Combined with 125I Seed Implantation for Non-Small-Cell Lung Cancer.

Objective To investigate the prognostic impact of computed tomography (CT) imaging big data-assisted arterial chemoembolization combined with iodine 125 (125I) seed implantation on patients with non-small-cell lung cancer (NSCLC). Methods A total of 116 patients with intermediate and advanced NSCLC hospitalized in our hospital from August 2019 to August 2020 were selected and divided into a control group and an experiment group (58 cases in each group) by random number table method for the study. The patients in the experiment group were treated with CT imaging big data-assisted arterial chemoembolization combined with 125I seed implantation, while the patients in the control group were treated with arterial chemoembolization alone, with the use of gemcitabine combined with cisplatin (GP) in chemotherapy. The prognostic impact was determined by analyzing recent efficacy; the incidence of adverse effects; tumor size and CT perfusion parameters including blood volume (BV), blood flow (BF), and permeability surface (PS); frailty state and quality of life; and the levels of serum tumor markers including carcinoembryonic antigen (CEA), glycoconjugate antigen 125 (CA125), cytokeratin 19 fragment antigen 21-1 (CYFRA21-1), microRNA- (miRNA-) 137, and miR-379-5p. In addition, frailty status was evaluated using the Fried frailty phenotype (FP) scale, and quality of life was determined according to Karnofsky Performance Status (KPS) score. Kaplan-Meyer (KM) method was used to analyze the survival rate of NSCLC patients after a 12-month follow-up. Results The remission rate in the experiment group (77.59%) was higher than that in the control group (56.90%) (P < 0.05). Tumor size, BV, BF, PS, serum CEA and CA125 levels, and FP value in both groups were dramatically reduced after treatment compared with before treatment, especially in the experiment group after 1 and 3 months of treatment (P < 0.05). Meanwhile, the serum miR-137 and miR-379-5p levels and KPS scores in both groups were higher after treatment than before treatment, especially in the experiment group after 1 and 3 months of treatment (P < 0.05). However, there was no significant difference in the incidence of nausea and vomiting, alopecia, diarrhea, myelosuppression, and hemoptysis of NSCLC patients in both groups after treatment (P > 0.05). Further, the 12-month survival rate of NSCLC patients was higher in the experiment group (84.21%) than in the control group (64.29%) (P < 0.05). Conclusion CT imaging big data-assisted arterial chemoembolization combined with 125I seed implantation for NSCLC can improve recent efficacy and the prognosis of NSCLC patients by inhibiting tumor progression with a certain degree of safety.

Feiji Recipe Elevates the Quality of Life of the Elderly with Lung Cancer on Docetaxel Plus Cisplatin Chemotherapy

We have evaluated the effect of Feiji recipe on efficacy of docetaxel plus cisplatin treatment on the quality of life of the elderly with lung cancer. To this end, 186 lung cancer patients receiving treatment at the Second People’s Hospital of Lianyungang, Lianyungang City, Jiangsu Province were recruited between January 2017 and December 2021 and randomly divided into control (receiving docetaxel + cisplatin) and treatment (receiving docetaxel + cisplatin + Feiji recipe) groups of 93 patients. Both groups received hydration on the day of cisplatin use and received preventive treatment for emesis, liver protection, acid suppression, and mucosal protection. Post-treatment depletion of cluster of differentiation 3 protein, cluster of differentiation 4 protein, and cluster of differentiation 4 protein/cluster of differentiation 8 protein levels in the treatment group were significantly (P &lt; 0.05) ameliorated/enhanced compared to the control group. Cluster of differentiation 3 protein and cluster of differentiation 4 protein/cluster of differentiation 8 protein levels in the treatment group were upregulated relative to controls (P &lt; 0.05), whereas cytokeratin 19 fragment antigen, cancer antigen 125, and carcinoembryonic antigen levels in the treatment group were depleted relative to controls after treatment (P &lt; 0.05). However, there was no significant difference in natural killer cell counts in the two groups before and after treatment (P &gt; 0.05). The overall treatment effectiveness (74.18% and 90.32%) and the progressive disease rates (25.82% and 9.68%) in the control and treatment groups, respectively (P &lt; 0.05). The physical/emotional/cognitive/role function scores in the treatment group were markedly increased compared to the control group (P &lt; 0.05). In conclusion, Feiji recipe markedly enhanced efficacy of all measures of treating lung cancer by docetaxel + cisplatin.

An ingenious electrochemical aptasensor for detection of CYFRA 21–1 based on dual-output toehold mediated strand displacement reaction

Herein, a “signal-on” electrochemical aptasensor based on dual-output toehold mediated strand displacement reaction (TMSDR) was developed to detect cytokeratin fragment antigen 21–1 (CYFRA 21–1). First, the methylene blue (MB) labeled signal probe (SP) was combined with a long template strand (TS) to form the three-strands duplex, which was immobilized on magnetic beads. The sequence of TS was innovatively designed with two toehold zones. Thus, with the presence of target DNA and Fuel strand (F), double SP and target were released through TMSDR. Besides, the released target could participate in the next cycle, achieving the further amplification. The released SP was selected by magnetic separation, then added to the gold electrode (GE) to hybridize with the hairpin DNA. Ultimately, the target can be detected by recording the current response of the MB. Under optimized conditions, the response peak current was linear with the concentration of CYFRA 21–1 in range from 10 pM to 1 μM with detection limit of 8.079 pM. The proposed signal amplification strategy was enzyme-free in homogenous solution and the using of magnetic beads improved the recognition efficiency and simplified the experimental steps, which endowed the sensor with super-sensitivity.

Detection of antibodies to Anaplasma phagocytophilum and Babesia microti using linear peptides

Anaplasma phagocytophilum and Babesia microti are emerging tick-borne pathogens in the United States. Although active infection is typically diagnosed by direct diagnostic tests, such as blood smear or polymerase chain reaction assay, serologic assays can be helpful to identify past infections, and the use of acute plus convalescent testing can potentially identify recent infections. We employed a peptide array to select sets of linear peptides for serologic diagnosis of infections with A. phagocytophilum and B. microti. Three optimal peptides were selected for each agent based on their performance with clinical specimens. All three A. phagocytophilum peptides were located within the conserved fragments of the MSP2 antigen. Two B. microti peptides were located in the N terminus of the SA-1 antigen; the third was in the BMN 1-17 antigen. We found that these peptides can be a useful tool for detection of antibody reactivity to both of these pathogens.

Preprint Highlight: Deciphering the tumor-specific immunopeptidome in vivo with genetically engineered mouse models.

Developing cancer immunotherapies relies on an accurate understanding of the diversity of cancer antigen–MHC complexes presented by immune cells, yet popular in vitro cell culture systems do not fully replicate the native tumor microenvironment. To characterize the cancer antigen fragments presented by immune cells in vivo, the authors engineered a mouse model with an affinity tag linked to the MHC heavy chain protein H2-Kb, enabling cell type-specific purification of cancer antigen–MHC complexes. In a mouse model of lung adenocarcinoma, this system revealed context-dependent changes in the peptide signatures obtained at different stages of tumorigenesis, including potential immunotherapeutic targets. Overall, this model offers a new way for the scientific community to evaluate in vivo immune cell interactions that is applicable across multiple cancer and disease settings.

Analysis on the Efficacy of Bronchial Artery Chemoembolization Combined with 125I Seed Implantation in the Therapy of Advanced Non-Small-Cell Lung Cancer Based on the Medical Database.

Objective To investigate the use and the efficacy of bronchial artery chemoembolization combined with 125I seed implantation in advanced non-small-cell lung cancer (NSCLC) therapy based on the medical database. Methods A total of 102 patients with advanced NSCLC were randomly divided into two groups. The control group was treated with 125I seed implantation, and the observation group was treated with bronchial artery chemoembolization (BACE) combined with 125I seed implantation based on medical database. The clinical efficacy, carcinoembryonic antigen (CEA), cytokeratin 19 fragment antigen 21-1 (CYFRA21-1), glycan antigen 125 (CA125), peripheral blood CD3+, CD8+, CD4+/CD8+ T cells, insulin-like growth factor type 1 receptor (IGF-1R), S100 calcium-binding protein A2 (S100A2), long-term efficacy (time to disease progression, six-month survival rate, and one-year survival rate), and safety were then analyzed. Result The disease remission rate in the observation group was 62.75%, which was higher than that in the control group (41.18%). After 1 month and 3 months of treatment, the levels of serum CYFRA21-1, CEA, CA125, and IGF-1R were lower, while serum S100A2 was higher in the observation group than in the control group (P < 0.05). For safety assessment, we found that the incidences of neutropenia, thrombocytopenia, and gastrointestinal reactions had no statistical differences between two groups. The time to disease progression in the observation group was 129.85 d longer than that in the control group, 89.74 d, and the six-month survival rate and 1-year survival rate were higher in the observation group relative to the control group. Conclusion Medical database-based BACE combined with 125I seed implantation in the therapy of advanced NSCLC patients has definite efficacy with certain safety, which can enhance antitumor effect and prolong survival rate in advanced NSCLC patients.

Heterologous Expression and Evaluation of Novel Plasmodium falciparum Transmission Blocking Vaccine Candidates.

Malaria transmission blocking vaccines (TBV) aim to induce antibodies that can interrupt Plasmodium falciparum development in the mosquito midgut and thereby prevent onward malaria transmission. A limited number of TBV candidates have been identified and only three (Pfs25, Pfs230 and Pfs48/45) have entered clinical testing. While one of these candidates may emerge as a highly potent TBV candidate, it is premature to determine if they will generate sufficiently potent and sustained responses. It is therefore important to explore novel candidate antigens. We recently analyzed sera from naturally exposed individuals and found that the presence and/or intensity of antibodies against 12 novel putative surface expressed gametocyte antigens was associated with transmission reducing activity. In this study, protein fragments of these novel TBV candidates were designed and heterologously expressed in Drosophila melanogaster S2 cells and Lactococcus lactis. Eleven protein fragments, covering seven TBV candidates, were successfully produced. All tested antigens were recognized by antibodies from individuals living in malaria-endemic areas, indicating that native epitopes are present. All antigens induced antigen-specific antibody responses in mice. Two antigens induced antibodies that recognized a native protein in gametocyte extract, and antibodies elicited by four antigens recognized whole gametocytes. In particular, we found that antigen Pf3D7_0305300, a putative transporter, is abundantly expressed on the surface of gametocytes. However, none of the seven novel TBV candidates expressed here induced an antibody response that reduced parasite development in the mosquito midgut as assessed in the standard membrane feeding assay. Altogether, the antigen fragments used in this study did not prove to be promising transmission blocking vaccine constructs, but led to the identification of two gametocyte surface proteins that may provide new leads for studying gametocyte biology.

Characteristics of antibody production to individual cytomegalovirus proteins in children with keratitis and uveitis

The clinical diagnosis of cytomegalovirus (CMV) eye pathology in children needs laboratory confirmation. The disadvantages of determining antibodies to CMV in serum in enzyme-linked immunosorbent assay (ELISA) include the presence of false positive and false negative results.&#x0D; AIM: To determine the features of the synthesis of antibodies to the proteins of the tegument pp65, pp150, pp28 and the DNA-binding protein pp52 of cytomegalovirus, as well as to compare the diagnostic effectiveness of two laboratory methods of serodiagnostics of CMVI in children with uveitis and keratitis of different genesis: enzyme immunoassay and linear immunolysis.&#x0D; MATERIAL AND METHODS: A total of 30 children (age 516 years) with uveitis (n=14) and keratitis (n=16) were included in the study. The IgM and IgG antibodies to the immediate early (IE) and late antigens of the virus (serological markers of primary, chronic, and reactivation of chronic infection) were determined in the ELISA. The IgG antibodies to individual recombinant CMV antigens containing only immunodominant protein fragments of viral antigens were studied in the line immunoassay (LIA): the main nonstructural IE protein, DNA-binding phosphoprotein p52, and phosphoproteins of the tegument p150, p65, and p28. The results of LIA were evaluated visually.&#x0D; RESULTS: CMV infection (CMVI) in children with uveitis in ELISA was almost 2 times higher than that with keratitis (10/14%71% vs. 6/16%37.5%, p 0.05). Of the four positive results for detection of antibodies to IE antigen in ELISA, one was confirmed in LIA. In general, the discrepancy between the results of the determination of IgG antibodies to IE antigen in ELISA and LIA was noted in 13% of serum samples. LIA showed the increased frequency (p 0.05) and intensity (p 0.05) of antibody formation to viral antigens p65 and p52 in uveitis compared with keratitis, which confirmed the important role of CMVI in the pathogenesis of uveitis.&#x0D; CONCLUSION: Both methods revealed a higher level of CMVI in children with uveitis than those with keratitis. IgG antibodies to IE-antigen serological markers of the reactivation of chronic CMVI have clinical importance because they serve as the basis for the appointment of antiviral therapy. Discrepancies between the results of ELISA and LIA in the detection of antibodies to IE antigen indicate the expediency of confirming the results of ELISA in LIA.&#x0D; Thus, laboratory examination of sera in ELISA with subsequent analysis of antibodies to individual recombinant CMV antigens in LIA is an effective, highly sensitive, and highly specific method to verify CMVI and determine its activity. The most informative action is the determination of IgG antibodies to recombinant CMV antigens: IE antigens, p65, and p52.

Identification of Naturally Processed Epitope Region Using Artificial APC Expressing a Single HLA Class I Allotype and mRNA of HCMV pp65 Antigen Fragments

Recently, long synthetic peptides or in silico-predicted epitope peptides have been used to identify T cell epitopes, but these approaches may not be suitable for investigating naturally processed epitopes. Here, mRNAs, including fragments or predicted epitope sequences of HCMV pp65 antigen, were generated by in vitro transcription following transcriptionally active PCR. Then, artificial antigen-presenting cells (aAPCs) expressing a single HLA allotype were transfected with mRNAs to identify epitopes in donors with T cell responses that recognize pp65 antigen restricted to HLA-A*02:01, -A*02:06, or -B*07:02. T cells restricted to a particular HLA allotype showed positive responses in some of the 10 fragment antigens. Among predicted epitopes within these positive fragments, three epitopes of HLA-A*02:01, -A*02:06, and -B*07:02 were confirmed. In addition, T cells expanded by anti-CD3 stimulation for two weeks could also be effectively used for the identification of these T cell epitopes, although there were individual differences. These results demonstrated that fragment antigens and epitopes can be rapidly generated using mRNA, and naturally processed antigenic regions can be detected using aAPCs without a T cell cloning procedure. This method will help to identify novel T cell epitopes for developing immunotherapy and vaccines against infectious diseases and cancer.

Vaccine Candidate Against COVID-19 Based on Structurally Modified Plant Virus as an Adjuvant.

A recombinant vaccine candidate has been developed based on the major coronaviruses’ antigen (S protein) fragments and a novel adjuvant—spherical particles (SPs) formed during tobacco mosaic virus thermal remodeling. The receptor-binding domain and the highly conserved antigenic fragments of the S2 protein subunit were chosen for the design of recombinant coronavirus antigens. The set of three antigens (Co1, CoF, and PE) was developed and used to create a vaccine candidate composed of antigens and SPs (SPs + 3AG). Recognition of SPs + 3AG compositions by commercially available antibodies against spike proteins of SARS-CoV and SARS-CoV-2 was confirmed. The immunogenicity testing of these compositions in a mouse model showed that SPs improved immune response to the CoF and PE antigens. Total IgG titers against both proteins were 9–16 times higher than those to SPs. Neutralizing activity against SARS-CoV-2 in serum samples collected from hamsters immunized with the SPs + 3AG was demonstrated.

Application of a novel microscopic technique for quantifying CA125 binding to circulating mononuclear cells in longitudinal specimens during treatment for ovarian cancer

BackgroundMeasurement of serum CA125, an antigenic fragment of human mucin 16 (MUC16), is used to monitor the clinical progression of epithelial ovarian cancer (EOC). However, rather than simply a passive marker reflecting tumor burden, MUC16 may have a more active role by binding to immune cells and altering their tumor response. We developed a research tool to measure MUC16-binding to the surfaces of peripheral blood mononuclear cell (PBMC) subtypes and tested its research value using specimens collected serially from a woman being treated for high grade serous EOC.MethodsCryopreserved PBMCs were mixed with anti-CA125 antibody-labeled plasmonic gold nanoparticles (PNPs) to detect cell surface MUC16-binding along with fluorescent stains to identify B cells, NK cells, NK-T cells, T cells, and monocytes. From 3D darkfield images, a computer algorithm was applied to enumerate PNP-binding and fluorescence microscopy to identify cell lineage. Average MUC16-binding was determined by fitting a Poisson distribution to PNP-counts across similar cell types. MUC16-binding to cell types was correlated with treatment details, CA125 levels, and complete blood count (CBC) data.ResultsOver a 21-month period, monocytes had the highest level of MUC16-binding which was positively correlated with serum CA125 and inversely correlated with circulating monocyte and lymphocyte counts. Fluctuations of PNP-binding to NK cells were associated temporally with types of chemotherapy and surgical events. Levels of MUC16 bound to NK cells were positively correlated with levels of MUC16 bound to T and NK-T cells and inversely correlated with circulating platelets.ConclusionsAssessment of MUC16-binding among cryopreserved PBMC cell types can be accomplished using darkfield and fluorescence microscopy. Correlations observed between level of binding by cell type with serum CA125, CBC data, and treatment details suggest that the new techniques may offer novel insights into EOC’s clinical course.

Molecular Dynamics Study of Citrullinated Proteins Associated with the Development of Rheumatoid Arthritis.

Biological activity regulation by protein post-translational modification (PTM) is critical for cell function, development, differentiation, and survival. Dysregulation of PTM proteins is present in various pathological conditions, including rheumatoid arthritis (RA). RA is a systemic autoimmune disease that primarily affects joints, and there are three main types of protein PTMs associated with the development of this disease, namely, glycosylation, citrullination, and carbamylation. Glycosylation is important for the processing and presentation of antigen fragments on the cell surface and can modulate immunoglobulin activity. The citrullination of autoantigens is closely associated with RA, as evidenced by the presence of antibodies specific to citrullinated proteins in the serum of patients. Carbamylation and dysregulation have recently been associated with RA development in humans.In this study, we performed an overview analysis of proteins with post-translational modifications associated with the development of RA adverted in peer-reviewed scientific papers for the past 20 years. As a result of the search, a list of target proteins and corresponding amino acid sequences with PTM in RA was formed. Structural characteristics of the listed modified proteins were extracted from the Protein Data Bank. Then, molecular dynamics experiments of intact protein structures and corresponding structures with PTMs were performed regarding structures in the list announced in the ProtDB service. This study aimed to conduct a molecular dynamics study of intact proteins and proteins, including post-translational modification and protein citrullination, likely associated with RA development. We observed another exhibition of the fundamental physics concept, symmetry, at the submolecular level, unveiled as the autonomous repetitions of outside the protein structural motif performance globule corresponding to those in the whole protein molecule.

Escherichia coli recombinant expression of SARS-CoV-2 protein fragments

We have developed a method for the inexpensive, high-level expression of antigenic protein fragments of SARS-CoV-2 proteins in Escherichia coli. Our approach uses the thermophilic family 9 carbohydrate-binding module (CBM9) as an N-terminal carrier protein and affinity tag. The CBM9 module was joined to SARS-CoV-2 protein fragments via a flexible proline–threonine linker, which proved to be resistant to E. coli proteases. Two CBM9-spike protein fragment fusion proteins and one CBM9-nucleocapsid fragment fusion protein largely resisted protease degradation, while most of the CBM9 fusion proteins were degraded at some site in the SARS-CoV-2 protein fragment. All of the fusion proteins were highly expressed in E. coli and the CBM9-ID-H1 fusion protein was shown to yield 122 mg/L of purified product. Three purified CBM9-SARS-CoV-2 fusion proteins were tested and found to bind antibodies directed to the appropriate SARS-CoV-2 antigenic regions. The largest intact CBM9 fusion protein, CBM9-ID-H1, incorporates spike protein amino acids 540–588, which is a conserved region overlapping and C-terminal to the receptor binding domain that is widely recognized by human convalescent sera and contains a putative protective epitope.

High-specificity targets in SARS-CoV-2 N protein for serological detection and distinction from SARS-CoV

Numerous serological detection kits are being rapidly developed and approved for screening and diagnosing suspected coronavirus disease 2019 (COVID-19) cases. However, cross-reactivity between pre-existing antibodies against other coronaviruses and the captured antigens in these kits can affect detection accuracy, emphasizing the necessity for identifying highly specific antigen fragments for antibody detection. Thus, we performed a conservation and specificity analysis of the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleocapsid (N) protein. We also integrated various B-cell epitope prediction methods to obtain possible dominant epitope regions for the N protein, analyzed the differences in serological antibody levels for different epitopes using ELISA, and identified N protein epitopes for IgG and IgM with high-specificity. The SARS-CoV-2 N protein showed low mutation rates and shared the highest amino acid similarity with SARS-CoV; however, it differed substantially from other coronaviruses. Tests targeting the SARS-CoV-2 N protein produce strong positive results in patients recovering from SARS-CoV. The N18–39 and N183-197 epitopes for IgG and IgM detection, respectively, can effectively overcome cross-reactivity, and even exhibit good specificity between SARS-CoV-2 and SARS-CoV. The antibody levels detected with these were consistent with those detected using the complete N protein. These findings provide a basis for serological diagnosis and determining the kinetics of SARS-CoV-2 antibody detection in patients.

Diagnostic, Prognostic, and Recurrence Monitoring Value of Plasma CYFRA21-1 and NSE Levels in Patients With Esophageal Squamous Cell Carcinoma.

This study was aimed to evaluate the clinical values of single markers and combination in the diagnosis, short-term efficacy and recurrence risk assessment of esophageal squamous cell carcinoma (ESCC).MethodsTotally 50 patients with I-IVa stage ESCC, 50 healthy controls and 11 patients with recurrent esophageal cancer after comprehensive treatment were enrolled. Serum biomarkers were collected and evaluated. Serum concentrations of carcinoembryonic antigen (CEA), cytokeratin 19 fragment antigen 21-1 (CYFRA21-1) and neuron specific enolase (NSE) were measured by enzyme-linked immunosorbent assay before and after treatment.ResultsThe diagnostic efficacy ROC curve area of CEA, CYFRA21-1 and NSE in esophageal cancer was 0.70, 0.71 and 0.64(all P <0.05), respectively, the sensitivity was 80%, 88.89% and 60% respectively, and the specificity was 53%, 58.5% and 58% respectively. The sensitivity and specificity of the combined detection were 68% and 78% respectively. The area under ROC curve was 0.75. CEA, CYFRA21-1 and NSE were significantly higher than the healthy control group and thus can be used as diagnostic markers of esophageal cancer (all P <0.05). After standard treatment, the clinical CR and PR rate of patients with positive CYFRA21-1 or NSE before treatment was significantly lower than that of patients with negative CYFRA21-1 or NSE (X2 = 4.52,P =0.03). A significant negative correlation was found between N stage and clinical efficacy (HR 2.48, 95%CI 1.07-5.73). After comprehensive treatment, the serum CYFRA21-1 and NSE levels in recurrent patients also increased significantly(all P<0.05), indicating these two markers play obvious roles in recurrence monitoring.ConclusionCYFRA21-1 and NSE may help to predict the response of ESCC to CRT, and play important roles in the diagnosis and recurrence monitoring of esophageal cancer. These markers have a diagnostic value of esophageal cancer when combined with CEA.

Conservation of vaccine antigen sequences encoded by sequenced strains of Streptococcus equi subsp. equi.

Streptococcus equi subspecies equi (S equi) is the cause of Strangles, one of the most prevalent diseases of horses worldwide. Variation within the immunodominant SeM protein has been documented, but a new eight-component fusion protein vaccine, Strangvac, does not contain live S equi or SeM and conservation of the antigens it contains have not been reported. To define the diversity of the eight Strangvac antigens across a diverse S equi population. Genomic description. Antigen sequences from the genomes of 759 S equi isolates from 19 countries, recovered between 1955 and 2018, were analysed. Predicted amino acid sequences in the antigen fragments of SEQ0256(Eq5), SEQ0402(Eq8), SEQ0721(EAG), SEQ0855(SclF), SEQ0935(CNE), SEQ0999(IdeE), SEQ1817(SclI) and SEQ2101(SclC) in Strangvac and SeM were extracted from the 759 assembled genomes and compared. The predicted amino acid sequences of SclC, SclI and IdeE were identical across all 759 genomes. CNE was truncated in the genome of five (0.7%) isolates. SclF was absent from one genome and another encoded a single amino acid substitution. EAG was truncated in two genomes. Eq5 was truncated in four genomes and 123 genomes encoded a single amino acid substitution. Eq8 was truncated in three genomes, one genome encoded four amino acid substitutions and 398 genomes encoded a single amino acid substitution at the final amino acid of the Eq8 antigen fragment. Therefore, at least 1579 (99.9%) of 1580 amino acids in Strangvac were identical in 743 (97.9%) genomes, and all genomes encoded identical amino acid sequences for at least six of the eight Strangvac antigens. Three hundred and seven (40.4%) isolates in this study were recovered from horses in the UK. The predicted amino acid sequences of antigens in Strangvac were highly conserved across this collection of S equi.

Reduced Graphene Oxide Based Electronic Sensors for Rapid and Label-Free Detection of CEA and CYFRA 21-1

Proper and early diagnosis of diseases is a key to efficient treatment and better prognosis. This paper reports a simple and label-free method of detection of two antigens – carcinoembryonic antigen (CEA) and cytokeratin-19 fragment (CYFRA 21-1) which are the biomarkers of many cancers including lung cancer. The sensor devices were fabricated by coating antibody/gold nanoparticles (AuNPs)/reduced graphene oxide (RGO) on indium tin oxide (ITO) coated glass. The sensors fabricated for detecting CEA had <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$6 ~\mu \text{L}$ </tex-math></inline-formula> of CEA antibodies and the ones developed for detecting CYFRA 21-1 were coated with <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$6 ~\mu \text{L}$ </tex-math></inline-formula> CYFRA 21-1 antibodies. The thickness of the graphene oxide was found to be ~1nm and the thickness of anti-CEA/AuNPs/RGO was found to be ~25 nm when observed using atomic force microscope. The sensing layers exhibited reflectance in the wavelength ranging from 248 to 300 nm when tested with UV-Visible spectrophotometer. A simple technique to capture the antibody-antigen binding has been developed in which the antigens are to be dropped onto the sensor devices and the change in the current across the sensors are to be measured. The biosensors were tested for 0.25 pg/mL to 20 ng/mL concentrations of CEA and CYFRA 21-1 at room temperature. The responses of the sensors ranged from 10.96 to 26.48% for 0.25 pg/mL to 20 ng/mL CEA and it varied from 17.66 to 26.68% for 0.25 pg/mL to 20 ng/mL CYFRA 21-1.

A capillary-driven LoC-SERS device integrated with catalytic hairpin assembly amplification technology for NSCLC-related biomarkers detection.

In this study, we apply catalytic hairpin assembly (CHA) as the signal amplification strategy for the quantification of carcinoembryonic antigen (CEA) and cytokeratin fragment antigen 21-1 (CYFRA21-1) with a surface-enhanced Raman scattering (SERS) microfluidic chip (LoC-SERS) as the carrier. Herein, antibody-DNA conjugates are designed to assist the application of CHA amplification in protein detection. In the presence of protein biomarkers, antibody-DNA conjugates can specifically bind to the target proteins, forming the antigen@antibody-DNA conjugates. The terminal free part of the DNA on the conjugates can trigger the CHA events to connect SERS nanotags to capture nanoprobes. Then, micro-magnet can gather the CHA products in a rectangular chamber, resulting in the aggregation of SERS nanotags, which can ultimately generate abundant "hot spots" for SERS signal enhancement. Using this strategy, CEA and CYFRA21-1 can be successfully determined with a limit of detection (LOD) as low as pg mL-1, much lower than recently reported methods. Meanwhile, a non-small cell lung cancer (NSCLC)-xenografted mouse model was established, and SERS was applied to analyze the expression level of CEA and CYFRA21-1 in tumorigenesis and development. The comparison between SERS results and those of the ELISA method demonstrated a high degree of consistency, suggesting that the proposed CHA-assisted LoC-SERS device has satisfying accuracy. Thus, introducing the CHA strategy via the design of antibody-DNA conjugates opens new gates to ultra-sensitive and specific SERS detection of protein biomarkers.