Neutralization activity of influenza A virus humanized antibodies against new subtypes of influenza viruses

Antibodies are ideal for controlling the influenza A virus,but their effect on newly emerging strains is unclear.Here,we assessed the neutralization activity of the humanized monoclonal antibodies(mAbs)F10,H98 and H40 against circulating influenza viruses(H5N1,H1N1,H3N2 and H7N7 and new subtypes viruses H5N6 and H7N9).The results showed that all the three humanized mAbs(F10,H98 and H40)displayed different degrees of virus neutralization activities when encountered with different subtypes of influenza viruses.Remarkably,the humanized monoclonal antibody F10 produced higher and broader neutralization titers(range 25–1.56μg/ml)than those of the other two humanized mAbs(H98(range 50–3.12μg/ml),H40(range 50–5.56μg/ml))to against the viruses H5N1,H1N1,H3N2,H7N7,H5N6 and H7N9.This mAb may represent a new class of heterosubtypic neutralizing humanized mAb that could replace vaccines and chemical drugs.

Similar Neutralizing Activity in the HIV-1 Infected Long Term Non-progressors(LTNPs) and Typical Progressors(TPs)

Neutralizing antibodies are considered to be an important protective parameter used in HIV-1 vaccine evaluation. However, the exact role that neutralizing antibodies plays in controlling the disease progression of HIV-1 infected peoples is still undetermined. In this paper, we compared the protective function of the neutralizing antibody response in the plasma from LTNP and TP against clade B and clade C pseudoviruses. No difference in the neutralizing activities between the plasma from LTNP and TP was found, which was consistent with the most recent reports. In addition, no correlations between the titer or breadth and CD4+ or viral load in HIV-1 infected individuals were found. The protective roles played by neutralizing antibodies in controlling disease progression of HIV-1 infected people need to be considered in a new viewpoint.

Rabies Virus Neutralizing Activity,Safety,and Immunogenicity of Recombinant Human Rabies Antibody Compared with Human Rabies Immunoglobulin in Healthy Adults

Objective Preliminary assessment of rabies virus neutralizing activity,safety and immunogenicity of a recombinant human rabies antibody(NM57)compared with human rabies immunoglobulin(HRIG)in Chinese healthy adults.Methods Subjects were randomly(1:1:1)allocated to Groups A(20 IU/kg NM57),B(40 IU/kg NM57),or C(20 IU/kg HRIG).One injection was given on the day of enrollment.Blood samples were collected on days-7 to 0(pre-injection),3,7,14,28,and 42.Adverse events(AEs)and serious AEs(SAEs)were recorded over a period of 42 days after injection.Results All 60 subjects developed detectable rabies virus neutralizing antibodies(RVNAs)(>0.05 IU/mL)on days 3,7,14,28,and 42.The RVNA levels peaked on day 3 in all three groups,with a geometric mean concentration(GMC)of 0.2139 IU/mL in Group A,0.3660 IU/mL in Group B,and0.1994 IU/mL in Group C.At each follow-up point,the GMC in Group B was significantly higher than that in Groups A and C.The areas under the antibody concentration curve over 0-14 days and 0-42 days in Group B were significantly larger than those in Groups A and C.Fifteen AEs were reported.Except for one grade 2 myalgia in Group C,the other 14 were all grade 1.No SAEs were observed.Conclusion The rabies virus neutralizing activity of 40 IU/kg NM57 was superior to that of 20 IU/kg NM57 and 20 IU/kg HRIG,and the rabies virus neutralizing activity of 20 IU/kg NM57 and 20 IU/kg HRIG were similar.Safety was comparable between NM57 and HRIG.

“Unconventional”Neutralizing Activity of Antibodies Against HIV

Neutralizing antibodies are recognized to be one of the essential elements of the adaptive immune response that must be induced by an effective vaccine against HIV. However, only a limited number of antibodies have been identified to neutralize a broad range of primary isolates of HIV-1 and attempts to induce such antibodies by inununization were unsuccessful. The difficulties to generate such antibodies are mainly due to intrinsic properties of HIV-1 envelope spikes, such as high sequence diversity, heavy glycosylation, and inducible and transient nature of certain epitopes. In vitro neutralizing antibodies are identified using ＂conventional＂ neutralization assay which uses phytohemagglutinin （PHA）-stimulated human PBMCs as target cells. Thus, in essence the assay evaluates HIV-1 replication in CD4^＋T cells. Recently, several laboratories including us demonstrated that some monoclonal antibodies and HIV-1-specific polyclonal IgG purified from patient sera, although they do not have neutralizing activity when tested by the ＂conventional＂ neutralization assay, do exhibit potent and broad neutralizing activity in ＂unconventional＂ ways. The neutralizing activity of these antibodies and IgG fractions is acquired through post-translational modifications, through opsonization of virus particles into macrophages and inunature dendritic cells （iDCs）, or through expression of antibodies on the surface of HIV-1-susceptible cells. This review will focus on recent findings of this area and point out their potential applications in the development of preventive strategies against HIV.

Preparation and Characterization of Monoclonal Antibodies against VP1 Protein of Foot-and-mouth Disease Virus O/China99

Monoclonal antibodies (McAbs) 1A9 and 9F12 against Foot-and-mouth disease virus (FMDV) serotype O were produced by fusing SP2/0 myeloma cells with splenocyte from the mouse immunized with O/China99. Both McAbs reacted with O/China99 but not with Asia 1, as determined by immunohistochemistry assay. The microneutralization titer of the McAbs 1A9 and 9F12 were 640 and 1 280, respectively. Both McAbs contain kappa light chains, but the McAbs 1A9 and 9F12 were IgG1 and IgM, respectively. In order to define the McAbs binding epitopes, the reactivity of these McAbs against VP1, P20 and P14 were examined using indirect ELISA, the result showed that both McAbs reacted with VP1 and P20. McAbs may be used for further studies of vaccine, diagnostic methods, prophylaxis, etiological and immunological researches on FMDV.

Develope Monoclonal Antibody against Foot-and-mouth Disease Virus A Type

In order to develop an anti-FMDV A Type monoclonal antibody （mAb）, BABL/c mice were immunized with FMDV A type. Monoclonal antibodies （mAbs） 7B 11 and 8H4 against Foot-and-mouth disease virus （FMDV） serotype A were produced by fusing SP2/0 myeloma cells with splenocyte from the mouse immunized with A/AV88. The microneutralization titer of the mAbs 7Bll and 8H4 were 1024 and 512, respectively. Both mAbs contain kappa light chainS, the mAbs were IgG1. In order to define the mAbs binding epitopes, the reactivity of these mAbs against A Type FMDV, were examined using indirect ELISA, the result showed that both mAbs reacted with A Type FMDV. These mAbs may be used for further vaccine studies, diagnostic methods, prophylaxis, etiological and immunological research on FMDV. Characterization of these ncindicated that prepared anti-FMDV A mAbs had no cross-reactivity with Swine Vesicular Disease （SVD） or FMDV O, Asial and C Type antigens. Their titers in abdomen liquor were 1：5×10^6 and 1：2×10^6, respectively. 7B 11 was found to be of subtype IgGb 8H4 was classified as IgG2b subtype. The mAbs prepared in this study, are specific for detection of FMDV serotype A, and is potentially useful for pen-side diagnosis.

Model predictive control of three-level active front-end converter with low switching frequency

In medium voltage-high power(MV-HP)applications,the high switching frequency of power converter will result in unnecessary energy losses,which directly affect efficiency.To resolve this issue,a novel finite control set-model predictive control(FCS-MPC)with low switching frequency for three-level neutral point clamped-active front-end converters(NPC-AFEs)is proposed.With this approach,the prediction model of three-level NPC-AFEs is established inα-βreference frame,and the control objective of low average switching frequency is introduced into a cost function.The proposed method not only achieves the desired control performance under low switching frequency,but also performs the efficient operation for the three-level NPC-AFEs.The simulation results are provided to verify the effectiveness of proposed control scheme.

Establishment of a Chinese street rabies virus library and its application for detecting neutralizing activity

Background:The injection of rabies immune globulin(RIG)is of the utmost importance in the management of category III exposures to rabies-suspect animals.Because of the high cost and limited availability of existing RIG,one possible replacement for RIG is monoclonal antibodies(MAbs)against the rabies virus(RABV).Consequently,it is necessary to determine the neutralizing activity of the MAbs against rabies viruses,especially street rabies virus.However,the method to detect the neutralizing activity of MAbs against street rabies virus remains undefined.Methods:To establish a method for detecting the neutralizing activity of MAbs against street rabies virus,we constructed a library consisting of 12 strains of street RABV from 11 provinces in China.Using this street RABV library and the Reed-Muench formula,we established a method for detecting the neutralizing titer of the MAbs.The reliability and repeatability of the method were evaluated by repeatedly measuring the neutralizing activity of a MAb and a post vaccination serum.Results:A total of 12 strains of street RABV were chosen for inclusion in the street RABV library,which covered six Chinese lineages(China I-China VI)and grew to high titers in N2A cells(>105 FFD50/ml).On the basis of the library,we constructed the method to detect the neutralizing activity of the MAbs.The results of repeatedly measuring the MAbs and positive serum showed excellent reliability and repeatability of the method established in this study.Conclusions:This study established a street RABV library reflecting the epidemiological features of Chinese rabies viruses,which provides a platform for detecting the neutralizing activity of MAbs against rabies viruses circulating in China.

Low-complexity model predictive control of a four-level active neutral point clamped inverter without weighting factors

The four-level active neutral point clamped(ANPC)inverter has become increasingly widely used in the renewable energy indus-try since it offers one more voltage level without increasing the total number of active switches compared to the three-level ANPC inverter.The model predictive current control(MPCC)is a promising control method for multi-level inverters.However,the conven-tional MPCC suffers from high computational complexity and tedious weighting factor tuning in multi-level inverter applications.A low-complexity MPCC without weighting factors for a four-level ANPC inverter is proposed in this paper.The computational burden and voltage vector candidate set are reduced according to the relationship between voltage vector and neutral point voltage balance.The proposed MPCC shows excellent steady-state and dynamics performances while ensuring the neutral point voltage balancing.The efficacy of the proposed MPCC is verified by simulation and experimental results.

Pathogenicity of an FAdV-4 isolate to chickens and its genomic analysis

Fowl adenovirus serotype 4(FAdV-4)strain SD1511 was isolated from chickens with severe inclusion body hepatitis and hydropericardium syndrome in Shandong Province,China.The isolate was cultured in primary chicken embryo kidney cells.A study of pathogenicity indicated that SD1511 readily infected 7–35-d-old chickens by intramuscular injection and intranasal and oral routes,causing 50%–100%mortality.The 35-d-old chickens suffered more severe infection than 7-and 21-d-old chickens with mortality highest in the intramuscular injection group.The serum from surviving chickens showed potent viral neutralizing capability.The complete genome of SD1511 was sequenced and analyzed.The strain was found to belong to the FAdV-4 cluster with more than 99%identity with the virulent FAdV-4 strains isolated in China in recent years except for some distinct variations,including deletions of open reading frame 27(ORF27),ORF48,and part of ORF19.Our findings suggest that SD1511 might be used as a prototype strain for the study of pathogenesis and vaccine development.

A broadly neutralizing human monoclonal antibody against the hemagglutinin of avian influenza virus H7N9

Background:The new emerging avian influenza A H7N9 virus,causing severe human infection with a mortality rate of around 41%.This study aims to provide a novel treatment option for the prevention and control of H7N9.Methods:H7 hemagglutinin(HA)-specific B cells were isolated from peripheral blood plasma cells of the patients previously infected by H7N9 in Jiangsu Province,China.The human monoclonal antibodies(mAbs)were generated by amplification and cloning of these HA-specific B cells.First,all human mAbs were screened for binding activity by enzyme-linked immunosorbent assay.Then,those mAbs,exhibiting potent affinity to recognize H7 HAs were further evaluated by hemagglutination-inhibiting(HAI)and microneutralizationin vitro assays.Finally,the lead mAb candidate was selected and tested against the lethal challenge of the H7N9 virus using murine models.Results:The mAb 6-137 was able to recognize a panel of H7 HAs with high affinity but not HA of other subtypes,including H1N1 and H3N2.The mAb 6-137 can efficiently inhibit the HA activity in the inactivated H7N9 virus and neutralize 100 tissue culture infectious dose 50(TCID_(50))of H7N9 virus(influenza A/Nanjing/1/2013)invitro,with neutralizing activity as low as 78 ng/mL.In addition,the mAb 6-137 protected the mice against the lethal challenge of H7N9 prophylactically and therapeutically.Conclusion:The mAb 6-137 could be an effective antibody as a prophylactic or therapeutic biological treatment for the H7N9 exposure or infection.

Palladium-catalyzed allylation of active methylene compounds with allyl perfluoroalkanoates under neutral conditions

Palladium-catalyzed allylation of carbonucleophiles has been widely used for carbon-carbon bond formation.Among the allylic compounds studied,allylic acetates were mostwidely used as precursors of(π-allyl)palladium intermediates.However,bases such as NaHmust be used to generate anions in this reaction.Recently,research on carrying out the palla-