Physical inability rather than depression and cognitive impairment had negative effect on centenarian prognosis: A prospective study with 5-year follow-up.

AIM: Scarce study has involved the effects of physical inability, depression and cognitive impairment on the prognosis of older individuals, especially in Chinese centenarians. This prospective study was designed to investigate the effects with 5-year follow-up in Chinese centenarians. METHODS: According to the list of centenarians provided by Department of Civil Affairs, an household survey was conducted on all centenarians residing in 18 cities and counties of Hainan province. A total of 423 centenarians were followed up, including 84 survival centenarians and 261 dead centenarians, with 78 cases lost to follow-up. RESULTS: Dead centenarians had less females and more physical inability than survival centenarians (P < 0.05 for all). Univariable Cox regression analyses indicated that physical inability [EXP(B): 2.038, 95 % confidence interval (CI): 1.413-2.939], urea nitrogen [EXP(B): 1.116, 95 % CI: 1.039-1.199], and creatinine [EXP(B): 1.006, 95 % CI: 1.001-1.012] had negative effects on the prognosis of centenarians (all P < 0.05). Gender [EXP(B): 0.606, 95 % CI: 0.391-1.940] and albumin [EXP(B): 0.939, 95 % CI: 0.896-0.985] had positive effects on the prognosis of centenarians (all P < 0.05). Multivariable Cox regression analysis indicated that physical inability [EXP(B): 2.148, 95 % CI: 1.454-3.173] and urea nitrogen [EXP(B): 1.114, 95 % CI: 1.020-1.216] had negative effects on the prognosis of centenarians (all P < 0.05). CONCLUSIONS: For Chinese centenarians, this prospective study demonstrated that physical inability rather than depression and cognitive impairment had negative effect on the long-term mortality rate and survival time. This result suggested that in order to improve the prognosis of older adults, it could be mainly achieved by improving physical ability.

In-depth characterization of protein N-glycosylation for a COVID-19 variant-design vaccine spike protein.

COVID-19 is caused by SARS-CoV-2 infection and remains one of the biggest pandemics around the world since 2019. Vaccination has proved to be an effective way of preventing SARS-CoV-2 infection and alleviating the hospitalization burden. Among different forms of COVID-19 vaccine design, the spike protein of SARS-CoV-2 virus is widely used as a candidate vaccine antigen. As a surface protein on the virus envelop, the spike was reported to be heavily N-glycosylated and glycosylation had a great impact on its immunogenicity and efficacy. Besides, N-glycosylation might vary greatly on different expression systems and sequence variant designs. Therefore, comprehensive analysis of spike N-glycosylation is of great significance for better vaccine understanding and quality control. In this study, full characterization of N-glycosylation was performed for a Chinese Hamster Ovary (CHO) cell expressed variant-designed spike protein. The spike protein featured the latest six-proline substitution design together with the incorporation of a combination of mutation sites. Trypsin and Glu-C digestion coupled with PNGase F strategies were adopted, and effective LC-MS/MS methods were applied to analyze samples. As a result, a total of 19 N-glycosites were identified in the recombinant pike protein at intact N-glycopeptide level. Quantitative analysis of released glycan by LC-MS/MS was also performed, and 31 high-abundance N-glycans were identified. Sequencing analysis of glycan was further provided to assist glycan structure confirmation. Moreover, all of the analyses were performed on three consecutive manufactured batches and the glycosylation results on both glycosite and glycans showed good batch-to-batch consistency. Thus, the reported analytical strategy and N-glycosylation information may well facilitate studies on SARS-CoV-2 spike protein analysis and quality studies.

Development of a flow cytometry method for detection of bovine multi-cytokines / 生物工程学报

This study aims to develop a method to detect bovine multi-cytokines based on flow cytometry. Previously we have prepared and screened monoclonal antibodies against bovine cytokines IFN-γ, IL-2, TNF-α, IP-10 and MCP-1. These bovine cytokine monoclonal antibodies were fluorescently labeled, and the combination of antibody and cell surface molecules were used to develop the method for detecting bovine multi-cytokines. Subsequently, the developed method was used to determine the cytokine expression profile of Mycobacterium bovis BCG infected bovine peripheral blood mononuclear cells in vitro, and evaluate the cytokine expression level of peripheral blood CD4+ T cells of tuberculosis-positive cattle. The bovine multi-cytokine flow cytometry detection method can effectively determine the cytokine expression of BCG-infected bovine peripheral blood T lymphocytes. Among them, the expression levels of IFN-γ, IL-2, and TNF-α continue to increase after 40 hours of infection, while the expression levels of IP-10 and MCP-1 decreased. The combined detection of IFN-γ, IL-2, and TNF-α on CD4+ T lymphocytes in peripheral blood of cattle can effectively distinguish tuberculosis-positive and tuberculosis-negative samples. This method may facilitate evaluating the level of cellular immune response after bovine pathogen infection and vaccine injection.

Characterization of the cellular immune response induced by Mycobacterium tuberculosis Rv2626c / 生物工程学报

Nearly a quarter of the world's population is infected with Mycobacterium tuberculosis and remains long-term asymptomatic infection. Rv2626c is a latent infection-related protein regulated by DosR of M. tuberculosis. In this study, the Rv2626c protein was prokaryotically expressed and purified, and its immunobiological characteristics were analyzed using RAW264.7 cells and mice as infection models. SDS-PAGE and Western blotting analysis showed that the Rv2626c-His fusion protein was mainly expressed in soluble form and specifically reacted with the rabbit anti-H37RV polyclonal serum. In addition, we found that the Rv2626c protein bound to the surface of RAW264.7 macrophages and up-regulated the production of NO. Moreover, the Rv2626c protein significantly induced the production of pro-inflammatory cytokines IFN-γ, TNF-α, IL-6 and MCP-1, and induced strong Th1-tendency immune response. These results may help to reveal the pathogenic mechanism of M. tuberculosis and facilitate the development of new tuberculosis vaccine.

A potent, broadly protective vaccine against SARS-CoV-2 variants of concern.

Since the first outbreak in December 2019, SARS-CoV-2 has been constantly evolving and five variants have been classified as Variant of Concern (VOC) by the World Health Organization (WHO). These VOCs were found to enhance transmission and/or decrease neutralization capabilities of monoclonal antibodies and vaccine-induced antibodies. Here, we successfully designed and produced a recombinant COVID-19 vaccine in CHO cells at a high yield. The vaccine antigen contains four hot spot substitutions, K417N, E484K, N501Y and D614G, based on a prefusion-stabilized spike trimer of SARS-CoV-2 (S-6P) and formulated with an Alum/CpG 7909 dual adjuvant system. Results of immunogenicity studies showed that the variant vaccine elicited robust cross-neutralizing antibody responses against SARS-CoV-2 prototype (Wuhan) strain and all 5 VOCs. It further, stimulated a TH1 (T Helper type 1) cytokine profile and substantial CD4+ T cell responses in BALB/c mice and rhesus macaques were recorded. Protective efficacy of the vaccine candidate was evaluated in hamster and rhesus macaque models of SARS-CoV-2. In Golden Syrian hamsters challenged with Beta or Delta strains, the vaccine candidate reduced the viral loads in nasal turbinates and lung tissues, accompanied by significant weight gain and relieved inflammation in the lungs. In rhesus macaque challenged with prototype SARS-CoV-2, the vaccine candidate decreased viral shedding in throat, anal, blood swabs over time, reduced viral loads of bronchus and lung tissue, and effectively relieved the lung pathological inflammatory response. Together, our data demonstrated the broadly neutralizing activity and efficacy of the variant vaccine against both prototype and current VOCs of SARS-CoV-2, justifying further clinical development.

Emergence and Tuning of Multiple Flat Bands in Twisted Bilayer γ-Graphyne.

Using twisted bilayer γ-graphyne (TBGY) as an example, we show that it is possible to create multiple flat bands in carbon allotropes without the requirement of a specified magic angle. The origin of the flat bands can be understood by a simple two-level coupling model. The narrow bandwidth and strong localization of the flat band states might lead to strong correlation effects, which make TBGY a good platform for studying correlation physics. On the basis of the two-level coupling model, we further propose that the width and extent of localization of flat bands can be tuned by an energy mismatch ΔE between the two layers of TBGY, which can be realized by either applying a perpendicular electric field or introducing a heterostrain. This allows continuous modulation of TBGY from the strong-correlation regime to the medium- or weak-correlation regime, which could be utilized to study the quantum phase transition.

Genome-wide analysis of 8-oxo-7,8-dihydro-2'-deoxyguanosine at single-nucleotide resolution unveils reduced occurrence of oxidative damage at G-quadruplex sites.

8-Oxo-7,8-dihydro-2'-deoxyguanosine (OG), one of the most common oxidative DNA damages, causes genome instability and is associated with cancer, neurological diseases and aging. In addition, OG and its repair intermediates can regulate gene transcription, and thus play a role in sensing cellular oxidative stress. However, the lack of methods to precisely map OG has hindered the study of its biological roles. Here, we developed a single-nucleotide resolution OG-sequencing method, named CLAPS-seq (Chemical Labeling And Polymerase Stalling Sequencing), to measure the genome-wide distribution of both exogenous and endogenous OGs with high specificity. Our data identified decreased OG occurrence at G-quadruplexes (G4s), in association with underrepresentation of OGs in promoters which have high GC content. Furthermore, we discovered that potential quadruplex sequences (PQSs) were hotspots of OGs, implying a role of non-G4-PQSs in OG-mediated oxidative stress response.

Development of recombinant COVID-19 vaccine based on CHO-produced, prefusion spike trimer and alum/CpG adjuvants.

COVID-19 pandemic has severely impacted the public health and social economy worldwide. A safe, effective, and affordable vaccine against SARS-CoV-2 infections/diseases is urgently needed. We have been developing a recombinant vaccine based on a prefusion-stabilized spike trimer of SARS-CoV-2 and formulated with aluminium hydroxide and CpG 7909. The spike protein was expressed in Chinese hamster ovary (CHO) cells, purified, and prepared as a stable formulation with the dual adjuvant. Immunogenicity studies showed that candidate vaccines elicited robust neutralizing antibody responses and substantial CD4+ T cell responses in both mice and non-human primates. And vaccine-induced neutralizing antibodies persisted at high level for at least 6 months. Challenge studies demonstrated that candidate vaccine reduced the viral loads and inflammation in the lungs of SARS-CoV-2 infected golden Syrian hamsters significantly. In addition, the vaccine-induced antibodies showed cross-neutralization activity against B.1.1.7 and B.1.351 variants. These data suggest candidate vaccine is efficacious in preventing SARS-CoV-2 infections and associated pneumonia, thereby justifying ongoing phase I/II clinical studies in China (NCT04982068 and NCT04990544).

Critical Role of Order-Disorder Behavior in Perovskite Ferroelectric KNbO3.

The evolution of local atomic configuration and macroscopic electrical properties of KNbO3 is investigated in detail using ab initio molecular dynamics simulations within the framework of density functional theory. By analyzing the local off-center displacements of K and Nb atoms, the presence of the crossover of displacive and order-disorder mechanisms in the NbO6 octahedron due to orbital hybridization is found, whereas the K is a completely displacive type due to the nonoriented ionic K-O bond. Besides, the order-disorder behavior of Nb atoms is enhanced with the increase in temperature, especially undergoing the phase transition. The predicted high dielectric constant of KNbO3 confirms the key role of the Nb's order-disorder behavior. We discover that the anomalous increase in dielectric constant in the vicinity of the phase boundary is not only from the transformation of the polarized direction but also from the enhancement of order-disorder contribution in the nonpolarized direction. The high dielectric constant with large spontaneous polarization boosts the piezoelectricity at the orthorhombic-tetragonal phase boundary of 500 K, giving rise to the nearly 100% increase than that of 300 K. A rebonding model is developed to illustrate the origin of high piezoelectricity around the tetragonal ferroelectric phase boundary, and the significance of introducing a tetragonal structure is emphasized for developing high piezoelectricity in the inorganic perovskite ferroelectrics.

Effect of sodium butyrate on ABC transporters in lung cancer A549 and colorectal cancer HCT116 cells.

Histone deacetylase (HDAC) inhibitors and DNA alkylators are effective components of combination chemotherapy. The aim of the present study was to investigate the possible mechanism of their synergism by detecting the effect of HDAC inhibitors on the expression levels of drug transporters that export DNA alkylators. It was demonstrated that the HDAC inhibitor sodium butyrate (NaB) induced the differential expression of multidrug resistant ATP-binding cassette (ABC) transporters in lung cancer and colorectal cancer cells. Specifically, NaB increased the mRNA expression levels of ABC subfamily B member 1 (ABCB1), ABCC10 and ABCC12, and protein expression levels of multidrug resistance-1 (MDR1), multidrug resistance-associated protein 7 (MRP7) and MRP9. Moreover, NaB decreased the expression levels of ABCC1, ABCC2 and ABCC3 mRNAs, as well as those of MRP1, MRP2 and MRP3 proteins. The molecular mechanism underlying this process was subsequently investigated. NaB decreased the expression of HDAC4, but not HDAC1, HDAC2 or HDAC3. In addition, NaB promoted histone H3 acetylation and methylation at lysine 9, as well as MDR1 acetylation, suggesting that acetylation and methylation may be involved in NaB-mediated ABC transporter expression. Thus, the present results indicated that the synergism of the HDAC inhibitors with the DNA alkylating agents may due to the inhibitory effect of MRPs by HDAC inhibitors. The findings also suggested the possibility of antagonistic effects following the combined treatment of HDAC inhibitors with MDR1 ligands.

Dissipation and residue determination of penicillin G and its two metabolites in citrus under field conditions by DSPE/UPLC-MS/MS.

A rapid determination method of residual penicillin G and its two metabolites in citrus was developed and validated by dispersive solid-phase extraction and ultra-high performance liquid chromatography-tandem mass spectrometry (DSPE/UPLC-MS/MS). The samples were extracted with 80% acetonitrile and purified with octadecylsilane. High linearity was obtained with correlation coefficients (r2 ) >0.9981. The limits of quantification were 0.005-0.01 mg/kg. The recoveries of penicillin G and its metabolites spiked in blank citrus were within 76.7-107%, with relative standard deviations of 1.3-9.6%. The dissipation dynamics and distribution of penicillin G in citrus followed first-order kinetics, with half-life of 1.7-2.7 days. Penicillin G degraded easily in citrus and the metabolite was mainly penilloic acid, which can exist stably for long time. The terminal residues of penicillin G in pulp, whole citrus and peels were 0.015-0.701, 0.047-7.653 and 0.162-13.376 mg/kg, respectively. The hazard indexes for risk assessment of citrus were significantly <1, suggesting that the health risks to humans after consumption of citrus were insignificant and negligible. These results could provide necessary data for evaluating the safe and proper use of penicillin G in citrus.

ISA 61 VG adjuvant enhances protective immune response of Listeria monocytogenes inactivated vaccine / 生物工程学报

Listeria monocytogenes (Lm) is zoonotic pathogen that can cause listeriosis, and vaccine is one of the effective methods to prevent this pathogen infection. In this study, we developed a novel vaccine that is a mixture of inactivated bacteria and Montanide™ ISA 61 VG, a mineral oil adjuvant, and evaluated the safety and immune response characteristics of this vaccine. The mice immunized with the ISA 61 VG adjuvant had high safety, and it could induce significantly higher titer of anti-listeriolysin O (LLO) antibody and higher value of IgG2a/IgG1 ratio compared with the group without the adjuvant. In particular, it could provide 100% immune protection against lethal doses of Lm challenge in mice. In summary, ISA 61VG adjuvant significantly enhanced the ability of inactivated listeria vaccine to induce humoral and cellular immune responses, thereby enhanced the protective immune response in the host, and it is a potential vaccine candidate for the prevention of Lm infection in humans and animals.

Size-controlled excitonic effects on electronic and optical properties of Sb2S3 nanowires.

In this work, the electronic and optical properties of one-dimensional (1D) Sb2S3 nanowires (NWs) with different sizes are investigated using first-principles calculations. The indirect-direct band transition of Sb2S3 NWs can be tuned effectively by the NW size and various uniaxial strains. In the Sb2S3 NWs, the quantum confinement effects result in wider bandgaps while the significantly enhanced electron-hole interaction that is expected to produce excitonic bound states generates a bandgap narrowing. The exciton binding energies for the Sb2S3 NWs are predicted by the effective masses of electrons and holes to lie in the range of 0-1 eV, which are larger than that of bulk Sb2S3, suggesting that excitons in Sb2S3 NWs may bind possible defects to promote luminescence. The size-controlled absorption edge blueshift and redshift of Sb2S3 NWs suggest that Sb2S3 NWs may be promising in the applications of nanoscale light emitting devices.

Willingness for downward referral and its influencing factors among rural elderlies with hospital stay in Shandong province / 中华医院管理杂志

Objective@#To understand the referral status and the willingness for downward referral among rural elderlies with hospital stay experiences in the past year in Shandong province, and to explore its influencing factors on the willingness for downward referral.@*Methods@#Three prefecture-level cities in Shandong province were sampled by multi-stage stratified random sampling in August 2017. Questionnaire survey was conducted among 910 rural elderlies(over 60 years old)who had been hospitalized in the past year. The study included the basic information, the hospitalization experience, and perception of essential medicines system, ego-resiliency, the referral status and willingness for downward referral. Rank sum test, Chi-square test and t test were used for univariate analysis, and logistic regression was applied for influencing factors.@*Results@#Among 910 rural elderlies who had been hospitalized in the past year, 53(5.8%) were referred to other medical institutions in their recent hospitalization, and 597(65.6%)were willing to be referred downward. The main reason for their reluctance for downward referral was that the medical competency of primary medical institutions was low; and the main reason for willingness for downward referral was being close to home. The results showed that marital status, impression for the national essential medicines system and ego-resiliency were the influencing factors of their willingness to downward referral among rural elderlies who had been hospitalized in the past year(P<0.05).@*Conclusions@#The referral rate and willingness for downward referral among the rural elderlies in Shandong province are relatively low. We should further enhance the service capacity of primary medical institutions, strengthen the publicity and implementation of the national essential medicines system, pay attention to help with the elderlies′ negative emotions caused by diseases, and improve their ego-resiliency.

Utilization of inpatient health care and its influencing factors among elderlies in Shandong province / 中华医院管理杂志

Objective@#To investigate the utilization of inpatient health care among the elderlies in Shandong province, and to analyze the factors affecting the inpatient services utilization, so as to provide reference for the elderlies to utilize the inpatient services reasonably.@*Methods@#The survey was conducted in Shandong province in August 2017. Multi-stage stratified cluster random sampling method was used to select 7 070 residents aged 60 and above in 6 counties and districts of Shandong province as the objects of the survey. The survey included the basic family and personal information of the elderlies as well as the utilization of hospitalization services. Chi-square test and rank sum test were used for univariate analysis, and logistic regression was applied for influencing factors.@*Results@#The annual hospitalization rate of the elderlies in Shandong province was 18.1%, and 9.6% of those in need of hospitalization failed to enjoy the service. The annual hospitalization rate of the elderlies aged 80 years and over was 19.9%, and 5.5% of the patients in need had not been hospitalized. Among the inpatient institutions, the proportion of township health centers/community health service centers, county-level(district) medical institutions, prefecture-level medical institutions and provincial-level medical institutions was 29.2%, 29.1%, 37.7% and 1.4%, respectively.Factors influencing the utilization of hospitalization services for the elderlies included age, self-assessment of health, physical examination, chronic diseases, type of medical insurance and income level.@*Conclusions@#More attention should be paid to the hospitalization services for the elderlies aged 80 years and over. Effective measures should be taken to guide the elderlies to fully use primary medical resources. The prevention and control of chronic diseases should be strengthened to promote the rational use of inpatient health services among the elderlies. In addition, more attention should be paid to low-income elderlies to meet their hospitalization needs.

Antibiotic resistome in farm animals and their related environments: a review / 生物工程学报

Overuse of antibiotics in livestock farming has enriched antibiotic-resistant genes as well as resistant bacteria in farm animals and their related environments. These antibiotic-resistant genes can spread to the natural environments by horizontal gene transfer and even to the food chain, posing a serious threat to the ecological environment, food safety and human health. With the development of genomic technology, the diversity and ecological distribution of antibiotic-resistant genes in farm animals and their related environments have been recently revealed. Here we summarized the research progress on antibiotic resistance genes in related fields, potential influence on human health, and future research needs.

Potential clinical value of detecting markers of bone metabolism in patients with ankylosing spondylitis / 中国免疫学杂志

Objective:To investigate the clinical significance of bone metabolism indexes and human leukocyte antigen B27 (HLA-B27)in ankylosing spondylitis(AS)and analyze their diagnostic value. Methods:The subjects were 94 cases of AS patients,239 cases with other diseases and 80 healthy controls, and the results were retrospectively surveyed. Results:In the AS group, the concentration of the β-collagen specific sequence (β-CTX ) was higher ( P<0. 05 ) while the concentrations of osteocalcin ( OC ) , 25-hydroxyvitamin D[25-(OH)D] and parathyroid hormone(PTH)were lower than those in the control group. In the AS group,there was a positive correlation between the concentration of C-reactive protein(CRP)and β-CTX(P<0. 01),and the concentration of CRP was negatively correlated with the concentration of 25-(OH)D(P<0. 05). However,the concentrations of other bone metabolic indexes had no correlation with the concentration of CRP(P<0. 05). The positive rate of HLA-B27 in the AS group was significantly higher than that in other groups(P<0. 05),and HLA-B27 had highly sensitive and specific in the diagnosis of AS. In the AS group,the sensitivity of the concentration of 25-( OH) D was higher than β-CTX,while its specificity was lower than β-CTX. Conclusion:Bone metabolic indexes have great value in early screening and clinical diagnosis of AS,especially β-CTX and 25-( OH) D were more obvious.

Development and evaluation of gamma-interferon sandwich ELISA kit in herds infected with Mycobacterium bovis / 中国人兽共患病学报

This study was aimed to develop a sandwich ELISA kit for the diagnosis of bovine tuberculosis.And it was applied and evaluated in the quarantine of bovine tuberculosis.We established a bovine IFN-γ release method in vitro and developing three batches of kits.The sensitivity,repeatability and retention period of the kit were all evaluated.Totally 961 serum samples were tested using the developed sandwich ELISA kit tuberculin skin test and a commercial ELISA kit.Our results showed that the detection limit of this ELISA was 8.21 mg/mL.The repeatability tests showed good reproducibility in the intraassay and inter-assay.At the same time,the retention period of the kit was more than 12 months.Compared with the tuberculin skin test,the positive coincidence rate was 70.59％ and the negative coincidence rate was 99.20％,while the total coincidence rate was 98.44％.And compared with the BOVIGAMTM kit,the positive coincidence rate was 91.30％ and the negative coincidence rate was 99.78％,while the total coincidence rate reached 99.58％.At the same time,the sensitivity and specificity of the sandwich kit were 85.00％ and 100％,respectively.We established a bovine IFN-γ release method in vitro and developing corresponding kits successfully have a good application prospect.

Potential clinical value of detecting markers of bone metabolism in patients with ankylosing spondylitis / 中国免疫学杂志

Objective:To investigate the clinical significance of bone metabolism indexes and human leukocyte antigen B27 (HLA-B27)in ankylosing spondylitis(AS)and analyze their diagnostic value. Methods:The subjects were 94 cases of AS patients,239 cases with other diseases and 80 healthy controls, and the results were retrospectively surveyed. Results:In the AS group, the concentration of the β-collagen specific sequence (β-CTX ) was higher ( P<0. 05 ) while the concentrations of osteocalcin ( OC ) , 25-hydroxyvitamin D[25-(OH)D] and parathyroid hormone(PTH)were lower than those in the control group. In the AS group,there was a positive correlation between the concentration of C-reactive protein(CRP)and β-CTX(P<0. 01),and the concentration of CRP was negatively correlated with the concentration of 25-(OH)D(P<0. 05). However,the concentrations of other bone metabolic indexes had no correlation with the concentration of CRP(P<0. 05). The positive rate of HLA-B27 in the AS group was significantly higher than that in other groups(P<0. 05),and HLA-B27 had highly sensitive and specific in the diagnosis of AS. In the AS group,the sensitivity of the concentration of 25-( OH) D was higher than β-CTX,while its specificity was lower than β-CTX. Conclusion:Bone metabolic indexes have great value in early screening and clinical diagnosis of AS,especially β-CTX and 25-( OH) D were more obvious.

Expression and assembly of chimeric flagellins in Escherichia coli BL21(DE3) and Salmonella / 生物工程学报

Flagellin can be expressed in monomeric or polymeric form based on assembly. The difference of these two forms of flagellin is less studied. In this experiment, recombinant plasmid pET-fliC/M2e2 was transferred into Escherichia coli BL21(DE3) and Salmonella SL5928 to express chimeric flagellin, mfliC/M and pfliC/M, respectively, and then their assembly characteristics were analyzed. Sodium dodecyl sulfate polyacrylamide gel electrophoresis results indicated that the two recombinant bacteria could successfully express chimeric flagellin. The transmission electronic microscope observation showed that no flagella were found on the surface of recombinant E. coli, whereas it was found for recombinant Salmonella. After purification, distinct circular dichroism spectra between them were found and pfliC/M showed the similar structure as wild-type flagellin, but not for mfliC/M. The dynamic light scattering assay also indicated that the polymerization of mfliC/M was much lower than that for pfliC/M. Three hours after transfection into mouse peritoneal macrophages, both could induce interleukin 1β secretion, but mfliC/M is stronger than pfliC/M. These data will be helpful for the selection of expression form of flagellin.