[Research progress in the regulation of pathogenesis and the transformation of chronic liver disease by short-chain fatty acids].

Short-chain fatty acids are metabolites of the intestinal flora and serve as the main energy source for intestinal epithelial cells. At the same time, as important signaling molecules, it regulate a variety of cellular inflammatory responses and homeostatic proliferation through receptor-dependent and independent pathways. Short-chain fatty acids regulate the gut-liver axis and thereby directly act on the liver, participating in the pathogenesis and transformation of various liver diseases, including alcoholic liver disease, metabolic dysfunction-related liver disease, autoimmune liver disease, liver fibrosis, and hepatocellular carcinoma. In addition, short-chain fatty acids can inhibit HBV DNA replication. This article reviews the research progress on the role of short-chain fatty acids in aspects of the pathogenesis and transformation of chronic liver diseases.

Fine mapping and analysis of a candidate gene controlling Phytophthora blight resistance in cucumber.

Cucumber blight is a destructive disease. The best way to control this disease is resistance breeding. This study focuses on disease resistance gene mapping and molecular marker development. We used the resistant cucumber, JSH, and susceptible cucumber, B80, as parents to construct F2 populations. Bulked segregant analysis (BSA) combined with specific length amplified fragment sequencing (SLAF-seq) were used, from which we developed cleaved amplified polymorphic sequence (CAPs) markers to map the resistance gene. Resistance in F2 individuals showed a segregation ratio of resistance:susceptibility close to 3:1. The gene in JSH resistant cucumber was mapped to an interval of 9.25 kb, and sequencing results for the three genes in the mapped region revealed three mutations at base sites 225, 302, and 591 in the coding region of Csa5G139130 between JSH and B80, but no mutations in coding regions of Csa5G139140 and Csa5G139150. The mutations caused changes in amino acids 75 and 101 of the protein encoded by Csa5G139130, suggesting that Csa5G139130 is the most likely resistance candidate gene. We developed a molecular marker, CAPs-4, as a closely linked marker for the cucumber blight resistance gene. This is the first report on mapping of a cucumber blight resistance gene and will provideg a useful marker for molecular breeding of cucumber resistance to Phytophthora blight.

[Demethylzeylasteral inhibits proliferation, migration and invasion and promotes apoptosis of non-small cell lung cancer cells by inhibiting the AKT/CREB signaling pathway].

OBJECTIVE: To investigate the mechanism underlying the inhibitory effects of Demethylzeylasteral (T-96) on non-small cell lung cancer (NSCLC) cells. METHODS: We first examined the effects of different concentrations (1, 3, 10, and 30 µmol/L) of demethylzeylasteral on morphology and cell number of A549 and H1299 cells. The changes in proliferation, cell viability, migration, invasion, and apoptosis of A549 and H1299 cells following demethylzeylasteral treatment were detected using clone formation, CCK-8, cell scratch, Transwell, and flow cytometric assays, and the effect of SC79 treatment against demethylzeylasteral-induced cell apoptosis was assessed. Western blotting was performed to detect the changes in expressions of E-cadherin, N-cadherin, vimentin, Bax, Bcl-2 and cleaved caspase-3 and phosphorylation of AKT/CREB in demethylzeylasteral-treated A549 and H1299 cells and the cellular expressions of apoptotic proteins following treatment with both demethylzeylasteral and SC79. RESULTS: T-96 treatment caused elongation of the cell body and widening of the intercellular space and significantly inhibited cell viability, proliferation, migration and invasion of A549 and H1299 cells (P < 0.05). Flow cytometry showed that demethylzeylasteral induced apoptosis in both A549 and H1299 cells, whereas SC79 treatment obviously attenuated its pro-apoptotic effect (P < 0.05). Western blotting revealed up-regulated expressions of Bax and cleaved caspase-3 proteins and lowered Bcl-2 expression level in demethylzeylasteral-treated A549 and H1299 cells, but cotreatment with SC79 obviously attenuated the expressions of the apoptotic proteins. T-96 significantly up-regulated the expression level of E-cadherin, down-regulated the expressions of N-cadherin and vimentin, and inhibited the phosphorylation of AKT and CREB in the two cell lines (P < 0.05). CONCLUSION: T-96 inhibits the proliferation, migration and invasion and induces apoptosis of NSCLC cells possibly by inhibiting the AKT/CREB signaling pathway.

Intestinal Translocation of Live Porphyromonas gingivalis Drives Insulin Resistance.

Periodontitis has been emphasized as a risk factor of insulin resistance-related systemic diseases. Accumulating evidence has suggested a possible "oral-gut axis" linking oral infection and extraoral diseases, but it remains unclear whether periodontal pathogens can survive the barriers of the digestive tract and how they play their pathogenic roles. The present study established a periodontitis mouse model through oral ligature plus Porphyromonas gingivalis inoculation and demonstrated that periodontitis aggravated diet-induced obesity and insulin resistance, while also causing P. gingivalis enrichment in the intestine. Metabolic labeling strategy validated that P. gingivalis could translocate to the gastrointestinal tract in a viable state. Oral administration of living P. gingivalis elicited insulin resistance, while administration of pasteurized P. gingivalis had no such effect. Combination analysis of metagenome sequencing and nontargeted metabolomics suggested that the tryptophan metabolism pathway, specifically indole and its derivatives, was involved in the pathogenesis of insulin resistance caused by oral administration of living P. gingivalis. Moreover, liquid chromatography-high-resolution mass spectrometry analysis confirmed that the aryl hydrocarbon receptor (AhR) ligands, mainly indole acetic acid, tryptamine, and indole-3-aldehyde, were reduced in diet-induced obese mice with periodontitis, leading to inactivation of AhR signaling. Supplementation with Ficz (6-formylindolo (3,2-b) carbazole), an AhR agonist, alleviated periodontitis-associated insulin resistance, in which the restoration of gut barrier function might play an important role. Collectively, these findings reveal that the oral-gut translocation of viable P. gingivalis works as a fuel linking periodontitis and insulin resistance, in which reduction of AhR ligands and inactivation of AhR signaling are involved. This study provides novel insight into the role of the oral-gut axis in the pathogenesis of periodontitis-associated comorbidities.

Expression of water-soluble nucleocapsid protein of SARS-CoV-2 and analysis of its immunogenicity.

Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to be a major public health concern. Nucleocapsid (N) protein is the most abundant structural protein on SARS-CoV-2 virions and induces the production of antibodies at the early stage of infection. Large-scale preparation of N protein is essential for the development of immunoassays to detect antibodies to SARS-CoV-2 and the control of virus transmission. In this study, expression of water-soluble N protein was achieved through inducing protein expression at 25°C with 0.5 mM IPTG for 12 h. Western blot and ELISA showed that recombinant N protein could be recognized by sera collected from subjects immunized with Sinovac inactivated SARS-CoV-2 vaccine. Four monoclonal antibodies namely 2B1B1, 4D3A3, 5G1F8, and 7C6F5 were produced using hybridoma technology. Titers of all four monoclonal antibodies in ELISA reached more than 1.28×10 6.0. Moreover, all monoclonal antibodies could react specifically with N protein expressed by transfection of pcDNA3.1-N into BHK-21 cells in IPMA and IFA. These results indicated that water-soluble N protein retained high immunogenicity and possessed the same epitopes as that of native N protein on virions. In addition, the preparation of water-soluble N protein and its monoclonal antibodies laid the basis for the development of immunoassays for COVID-19 detection.

Development of an energy spread analyzer for secondary ion mass spectrometry ion source.

The energy spread (ΔE) of an ion source is an important parameter in the production of a finely focused primary ion beam applied in secondary ion mass spectrometry (SIMS). A variable-focusing retarding field energy analyzer (RFEA) has been developed and tested with an Ar+ beam and an oxygen ion beam extracted from a 2.45 GHz microwave ion source, which is developed as a candidate ion source for SIMS applications. The simulation results show that the relative resolution ΔE/E of the designed RFEA reaches 7 × 10-5. The experimental results indicate that a focusing electrode can improve the ΔE measurement results, which is consistent with the simulation results. The ion energy distributions of the Ar+ beam and oxygen ion beam are of Gaussian distribution with the value of ΔE of 3.3 and 2.9 eV, respectively. These results indicate that the designed RFEA is reliable for measuring the ion beam energy spread. The developed RFEA is also used to study the plasma behavior in different settings, which reveals that plasma stability is critical to making a low energy spread ion beam. This paper will present the simulation, design, and test of the variable-focusing RFEA. Preliminary ion beam quality studies with this instrument will also be discussed.

[Update points for the 2022 edition of the European Association for the Study of Liver Diseases Clinical Practice Guidelines for the Management of Hepatic Encephalopathy and comparison with China's 2018 edition guidelines].

The European Association for the Study of Liver Diseases issued the "Clinical Practice Guidelines for the Management of Hepatic Encephalopathy" in 2022, which included recommendations for clinical diagnosis, assessment, treatment, management, and prevention. The Society's "Hepatic Encephalopathy Clinical Practice Guidelines in Chronic Liver Disease," which was last published in 2014, and the "Guidelines for the Diagnosis and Treatment of Hepatic Encephalopathy in Cirrhosis," which the Chinese Society of Hepatology, Chinese Medical Association, released in 2018, have certain differences and updates in terms of comparison to terminology, grading and classification, diagnosis, clinical evaluation and treatment, management, and prevention. Herein, the updated points of this guideline and the differences between it and our nation's guidelines are summarized in order to refine and understand the guiding role of the new version of the guideline for the clinical treatment of hepatic encephalopathy and provide aid for standardizing clinical diagnosis and treatment.

Matrine From Sophora Flavescens Attenuates on Collagen-Induced Osteoarthritis by Modulating the Activity of miR-29B-3P/PGRN Axis.

Matrine is an active ingredient in traditional Chinese medicine that has been shown to be effective in treating bone disorders. The anti-osteoarthritis (OA) effects of matrine were assessed using both in in vitro and in vivo systems, and the mechanisms underlying the effects were investigated by focusing on the activity of miR-29b-3p/PGRN axis. The miR was chosen as potential target for matrine after chondrocytes were treated with both IL-1? and matrine. Changes in cell viability, cell apoptosis, inflammation, and miR-29b-3p/PGRN axis were detected. In vitro assays results were validated using collagen-induced arthritis (CIA) rat models. Incubation with IL-1? reduced cell viability, induced cell apoptosis, and inhibited production of cytokines in chondrocytes, which was associated with the up-regulation of miR-29b-3p and down-regulation of PGRN. In CIA rats, matrine reduced bone destruction and weight loss in a dose-dependent manner. Matrine also reduced the systemic levels of cytokines. At the molecular level, matrine inhibited the expression of miR-29b-3p while increasing the expression of PGRN. The findings outlined in the current study showed that matrine exerted its anti-OA effects by modulating the miR-29b-3p/PGRN axis.

A compact radio-frequency ion source for high brightness and low energy spread negative oxygen ion beam production.

A high brightness and low energy spread (∆E) ion source is essential to the production of a high-quality primary ion beam applied in secondary ion mass spectrometry (SIMS). A compact 13.56 MHz radio-frequency (RF) ion source with an external planar spiral antenna has been developed as a candidate ion source for the production of negative oxygen ion beams for SIMS application. This ion source is designed with a three-and-a-half-turn water-cooled planar antenna for RF power coupling, a multi-cusp magnetic field for effective plasma confinement, and a three-electrode extraction system. The experimental results show that more than 50 µA negative oxygen ion beams have been extracted, which consist of 56% O-, 25% O2-, and 19% O3-. The ion energy distribution of the negative oxygen ion beam exhibits a Gaussian distribution with a minimum ∆E of 6.3 eV. The brightness of the O- beam is estimated to be 82.4 A m-2 Sr-1 V-1. The simulation, design, and experimental study results of this RF ion source will be presented in this paper.

[The efficacy of thin struct bare stents for the treatment of spontaneous isolated dissection of the superior mesenteric artery].

Objective: To examine the safety and effectiveness of thin struct bare stents for the treatment of spontaneous isolated dissection of the superior mesenteric artery (SIDSMA). Methods: The data of 32 patients admitted to First Hospital of Jiaxing (20 cases) and Jinling Hospital (12 cases) with SIDSMA from January 2016 to January 2021 were retrospectively analyzed. There were 27 males and 5 females, aging (54.8±9.4) years (range: 36 to 75 years). All patients were treated with thin struct bare stents. Controllable spring coils were used to fulfill the false lumen in 2 cases. Symptoms, vascular remodeling pattern at the SIDSMA lesion, and patency of the stents were observed during follow-up. Results: The surgical success rate was 100%. According to the length of the lesions and stents, the number of stents implanted was 1 in 17 cases, 2 in 11 cases and 3 in 4 cases. The angiography showed that blood flow in the stent was smooth and that the false lumen disappeared or weakened. The numerical rating scale for abdominal pain decreased from 6.1±1.5 (range: 4 to 10) preoperatively to 1.0 (1.0) (range: 0 to 3) 1 hour postoperatively (W=528, P<0.01). The compression rate of the true lumen of the superior mesenteric artery decreased from (92.3±6.7)% (range: 25% to 94%) preoperatively to 0.8 (1.2)% (range: 0 to 3.2%) 1 month postoperatively (W=528, P<0.01). The primary patency rate of CT angiography at 1 month postoperatively was 100%. The vascular remodeling rate was (92.3±6.7)% (range: 80% to 100%). All patients were followed for (46.3±17.0) months (range: 24 to 76 months). The cumulative patency rates in 1, 2 and 5 years were all 100%. Conclusion: The use of thin struct bare stents for SIDSMA is safety and efficacy.

Morin protects chicks with T-2 toxin poisoning by decreasing heterophil extracellular traps, oxidative stress and inflammatory response.

1. Fusarium tritici widely exists in a variety of grain feeds. The T-2 toxin is the main hazardous component produced by Fusarium tritici, making a serious hazard to poultry industry. Morin, belonging to the flavonoid family, can be extracted from mulberry plants and possesses anticancer, antioxidant and anti-inflammatory compounds, but whether morin protects chicks with T-2 toxin poisoning remains unclear. This experiment firstly established a chick model of T-2 toxin poisoning and then investigated the protective effects and mechanism of morin against T-2 toxin in chicks.2. The function of liver and kidney was measured by corresponding alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), blood urea nitrogen (BUN), creatinine (Cre) and uric acid (UA) kits. Histopathological changes were observed by haematoxylin-eosin staining. The status of oxidative stress was measured by MDA, SOD, CAT, GSH and GSH-PX kits. The mRNA levels of TNF-α, COX-2, IL-1ß, IL-6, caspase-1, caspase-3 and caspase-11 were measured by quantitative real-time PCR. Heterophil extracellular trap (HET) release was analysed by immunofluorescence and fluorescence microplate.3. The model with T-2 toxin poisoning in chicks was successfully established. Morin significantly decreased T-2 toxin-induced ALT, AST, ALP, BUN, Cre and UA, and improved T-2 toxin-induced liver cell rupture, liver cord disorder and kidney interstitial oedema. Oxidative stress analysis showed that morin ameliorated T-2 toxin-induced damage by reducing malondialdehyde (MDA), increasing superoxide dismutase (SOD), catalase (CAT), glutathione (GSH) and glutathione peroxidase (GSH-PX). The qRT-PCR analysis showed that morin reduced T-2 toxin-induced mRNA expressions of TNF-α, COX-2, IL-1ß, IL-6, caspase-1, caspase-3 and caspase-11. Moreover, morin significantly reduced the release of T-2 toxin-induced HET in vitro and in vivo.4. Morin can protect chicks from T-2 toxin poisoning by decreasing HETs, oxidative stress and inflammatory responses, which make it a useful compound against T-2 toxin poisoning in poultry feed.

Light-triggered cardiac microphysiological model.

Light is recognized as an accurate and noninvasive tool for stimulating excitable cells. Here, we report on a non-genetic approach based on organic molecular phototransducers that allows wiring- and electrode-free tissue modulation. As a proof of concept, we show photostimulation of an in vitro cardiac microphysiological model mediated by an amphiphilic azobenzene compound that preferentially dwells in the cell membrane. Exploiting this optical based stimulation technology could be a disruptive approach for highly resolved cardiac tissue stimulation.

[Revision rate of periprosthetic joint infection post total hip or knee arthroplasty of 34 hospitals in China between 2015 and 2017: a multi-center survey].

Objective: To investigate the rate of periprosthetic joint infection (PJI) revision surgeries and clinical information of hip-/knee- PJI cases nationwide from 2015 to 2017 in China. Methods: An epidemiological investigation. A self-designed questionnaire and convenience sampling were used to survey 41 regional joint replacement centers nationwide from November 2018 to December 2019 in China. The PJI was diagnosed according to the Musculoskeletal Infection Association criteria. Data of PJI patients were obtained by searching the inpatient database of each hospital. Questionnaire entries were extracted from the clinical records by specialist. Then the differences in rate of PJI revision surgery between hip- and knee- PJI revision cases were calculated and compared. Results: Total of 36 hospitals (87.8%) nationwide reported data on 99 791 hip and knee arthroplasties performed from 2015 to 2017, with 946 revisions due to PJI (0.96%). The overall hip-PJI revision rate was 0.99% (481/48 574), and it was 0.97% (135/13 963), 0.97% (153/15 730) and 1.07% (193/17 881) in of 2015, 2016, 2017, respectively. The overall knee-PJI revision rate was 0.91% (465/51 271), and it was 0.90% (131/14 650), 0.88% (155/17 693) and 0.94% (179/18 982) in 2015, 2016, 2017, respectively. Heilongjiang (2.2%, 40/1 805), Fujian (2.2%, 45/2 017), Jiangsu (2.1%, 85/3 899), Gansu (2.1%, 29/1 377), Chongqing (1.8%, 64/3 523) reported relatively high revision rates. Conclusions: The overall PJI revision rate in 34 hospitals nationwide from 2015 to 2017 is 0.96%. The hip-PJI revision rate is slightly higher than that in the knee-PJI. There are differences in revision rates among hospitals in different regions.

[Protection of side-branch ostium by the jailed balloon technique validated by three-dimensional optical coherence tomography].

Objective: To evaluate the protective effect of jailed balloon technique on side branch (SB) ostium using three-dimensional optical coherence tomography(OCT). Methods: This is a retrospective study. Consecutive coronary disease patients with coronary artery bifurcation lesions who underwent percutaneous coronary intervention (PCI) and completed pre-and post-procedural OCT examinations at the Chinese People's Liberation Army General Hospital from September 2019 to March 2022 were enrolled. Patients were divided into the jailed balloon technique group and the unprotected group according to the options applied for the SB. The SB ostium area difference was calculated from OCT images (SB ostium area difference=post-PCI SB ostium area-pre-PCI SB ostium area). The SB ostium area differences were compared between the two groups and compared further in the subgroup of true bifurcation lesions and non-true bifurcation lesions. In the jailed balloon group, the SB ostium area difference was compared between the active jailed balloon technique and the conventional jailed balloon technique, between the jailed balloon>2.0 mm diameter and the jailed balloon≤2.0 mm diameter, and between the higher balloon pressure (>4 atm, 1 atm=101.325 kPa) and the lower balloon pressure (≤4 atm). Multivariate linear regression analysis was used to explore the correlation between the technical parameters of the jailed balloon technique and the SB protection effect. Results: A total of 176 patients with 236 bifurcation lesions were enrolled, aged (60.7±9.3) years, and there were 128 male patients (72.7%). There were 67 patients in the jailed balloon technique group with 71 bifurcation lesions and 123 patients in the unprotected group with 165 bifurcation lesions. Fourteen patients had 2 to 3 lesions, which were treated in different ways, so they appeared in the unprotected group and the jailed balloon technique group at the same time. The area difference in SB ostium was greater in the jailed balloon group than in the unprotected group (0.07 (-0.43, 1.05)mm2 vs.-0.33 (-0.83, 0.26)mm2, P<0.001), and the results were consistent in the true bifurcation lesion subgroup (0.29 (-0.35, 0.96)mm2 vs.-0.26 (-0.64, 0.29)mm2, P=0.004), while the difference between the two groups in the non-true bifurcation lesion subgroup was not statistically significant (P=0.136). In the jailed balloon technique group, the SB ostium area difference was greater in patients treated with the active jailed balloon technique than in those treated with the conventional jailed balloon technique ((0.43±1.36)mm2 vs. (-0.22±0.52)mm2, P=0.013). The difference in SB ostium area was greater in those using>2.0 mm diameter jailed balloons than in those using≤2.0 mm diameter jailed balloons (0.25 (-0.51, 1.31) mm2 vs.-0.01 (-0.45, 0.63) mm2, P=0.020), while SB ostium area difference was similar between those endowed with higher balloon pressure (>4 atm) compared to those with lower balloon pressure (≤4 atm) (P=0.731). Multivariate linear regression analysis showed that there was a positive correlation between jailed balloon diameter and SB ostium area difference (r=0.344, P=0.019). Conclusions: The jailed balloon technique significantly protects SB ostium, especially in patients with true bifurcation lesions. The active jailed balloon technique and larger diameter balloons may provide more protection to the SB.

[Occurrence and recovery of adverse drug reactions of preventive treatment in elderly population with latent tuberculosis infection].

Objective: To evaluate the occurrence and recovery of adverse drug reactions (ADRs) of preventive treatment in the elderly population with latent tuberculosis infection (LTBI). Methods: A total of 2 583 elderly patients with LTBI were recruited in Zhongmu, Henan Province from July 1 to October 17, 2015. Face-to-face surveys and physical examinations were used to obtain the basic information of the participants, and the body mass index (BMI) was calculated. Fasting venous blood was collected from the participants for blood biochemical and routine blood tests. The random numbers were generated by Excel 2010, and the participants were divided into group A (1 284 cases) and group B (1 299 cases) by simple randomization. Both group A and group B received combination treatment of isoniazid and rifapentine. Group A was treated for 8 weeks with weekly doses of isoniazid at 15 mg/kg and 900 mg for those with body weight ≤50 and>50 kg, respectively, and the doses of rifapentin were 750 and 900 mg, respectively. Group B was treated twice a week for 6 weeks, the doses of isoniazid in patients with body weight ≤50 and>50 kg were [600-(50-body weight)×15] (rounded up) and 600 mg, respectively, and the doses of rifapentin were 600 and 450 mg, respectively. During the treatment period, doctors observed, inquired about and recorded symptoms related to ADRs, and blood biochemical and routine blood tests were performed at 4 weeks after taking the drug, the end of the treatment, and 3 months after the end of the treatment. The patients with ADRs were treated accordingly by severity. The ADRs and graded treatment outcomes of LTBI patients in group A and group B were compared. Results: The ageï¼»M（Q1，Q3）］of the participants was 60 (55,65) years old, and 54.7% (1 412/2 583) were males. There were no statistical differences in age, gender, BMI and baseline biochemical indexes between groups A and B (all P values>0.05). The incidence of ADRs in group A and group B were 18.5% (237/1 279) and 16.3% (209/1 279), respectively, and those with alanine aminotransferase (ALT)≥5 ULN accounted for 0.8% (7/931) and 1.1% (11/987), aspartate aminotransferase (AST)≥5 ULN accounted for 0.3% (3/931) and 0.3% (3/987), respectively, and there were no statistically significant differences (all P values>0.05). There were 7 and 11 patients with ALT≥5 ULN in group A and group B, respectively, and 3 patients with AST≥5 ULN for each group, respectively. After treatment, except for 2 patients with ALT≥5 ULN in group B, ALT and AST levels in all the other patients returned to normal. There were 15 and 10 patients with abnormal white blood cell count in group A and group B, respectively, and 10 and 9 patients returned to normal after treatment. Conclusion: LTBI preventive treatment has a high incidence of adverse drug reactions, but it can be effectively controlled through active monitoring and graded management.

Multi-objective utilization of wood waste recycled from construction and demolition (C&D): Products and characterization.

Producing energy and higher value bio-products from waste materials has been proposed as an economically viable opportunity in the renewable energy sector. However, several challenges associated with the integrated biomass conversion processes remain to be resolved. The present study introduces a multi-faceted plant production of thermal energy and biochar from construction and demolition (C&D) wood chips. The overarching objective of the study is to reduce waste materials while simultaneously producing a self-independent clean thermal energy resource along with value-added co-products such as biochar, biogases and/or activated carbon. The combined thermal energy and slow pyrolysis unit relies on 95% of its energy from waste wood chips to produce thermal energy and high value carbon products. The system not only supplies the energy required for the indirect pyrolysis unit but also provides a major portion of thermal energy demanded for the site. A multi-purpose objective of wood waste management, energy production from waste material, high-quality biochar from waste wood (over 80% carbon), and carbon offsets is demonstrated through the utilization of this plant by addressing some of the major previously problems and challenges faced. The information is useful for techno-economic and life cycle analysis in the next study.

Rapid screening of monoclonal antibodies against porcine circovirus type 2 using colloidal gold-based paper test.

A proof of concept for using paper test as a suitable method in the production of monoclonal antibodies (MAbs) is reported. The paper test which detects antibodies against porcine circovirus type 2 (PCV2) using colloidal gold-labelled capsid protein as the antigen probe was applied exclusively in the screening of anti-PCV2 MAbs. It allowed the detection of 118 single cell clones within 30 min using naked eyes. MAbs with specific binding to authentic epitopes on the virus were selected using a blocking strategy in which the antibody was pre-incubated with PCV2 viral sample before applying to the test paper. Five hybridomas secreting MAbs against the capsid protein were obtained, with only three of them capable of binding to PCV2. The results were validated and confirmed using enzyme-linked immunosorbent assay and immunofluorescence assay. The paper test is simple, rapid, and independent on professional technicians and proves to be an excellent approach for the screening of MAbs against specific targets.