Adjuvants Derived from <i>Neisseria meningitidis</i>Serogroup B Induce a Cross Reactive Response against <i>Neisseria gonorrhoeae</i>in Mice

Introduction: Neisseria is a large genus of bacteria that colonize mucosal surfaces. Of the 11 species that colonize humans, only two are pathogens, N. meningitidis and N. gonorrhoeae. Both are obligate human pathogens;the last is causal agent of gonorrhea disease. Although curable with timely antibiotic treatment, an annual incidence of more than 62 million cases is estimated by the World Health Organization and there are no successful vaccines available. In contrast, several prophylactic vaccine options for Neisseria meningitidis meningitis do exist. Of note, there is trace of cross parenteral response induced between N. meningitidis and N. gonorrhoeae, and Proteoliposome (PL, also named outer membrane vesicles, OMV) vaccine has shown high impact on this response. Objective: To determine effect of VAMENGOC-BC? and its derivates (AFPL1 and AFCo1) at mucosal and systemic level and possible cross response against Neisseria gonhorroeae in Balb/c and C57Bl/6 mice. Methods: We evaluated cross response against N. gonorrhoeae in mouse serum IgG and saliva IgA after mucosal immunization with VA-MENGOC-BC or its derivatives (AF, Adjuvant Finlay PL1 or AFCo (cochleate) 1). Results: Immunizations with AFPL1 or AFCo1 induce anti N. gonorrhoeae at saliva IgA and serum IgG responses similar to VA-MENGOC-BC? vaccine. Conclusions: Such data confirms a new possible window of prime-boost vaccination strategy against gonorrhea and extends our knowledge regarding the effect of PL vaccines on cross responses.

Theoretical Investigation for Two-state Reactivity of CO_2 Hydrogenation Catalyzed by Ru in Gas Phase

Gas-phase CO_2 catalyzed activation hydrogenation by Ru atoms was studied with density functional theory. Based on the structure optimization of different potential energy surfaces,there are two crossing points between singlet and triplet potential energy surfaces and there is a crossing point between quintet and triplet potential energy surfaces in the whole catalytic cycle. Spin transition probabilities in the vicinity of the intersections have been calculated by the Landau-Zener model theory. There are three minimum energy crossing points（MECPs） with strong spin-orbital coupling effect and higher spin transition probability,and all spin inversion occurred in s orbital and different d orbitals of ruthenium,indicating this is a typical two-state reactivity（TSR） reaction. Finally,the lowest energy reaction path is ensured.

Expression and Identification of the Type-specific Antigen of FMDV of Serotype C

[Objective]The aim was to provide a theoretical basis for preparation of polyclonal antibodies and monoclonal antibody that of type specificity, as well as Foot-and-mouth Disease Virus （FMDV） typing.[Method] The recombinant plasmid pGEM-CP1 that contained VPI gene of FMDV of serotype C was used as template for the VP1 and its C terminus coding fragments of FMDV of serotypes C amplification. The coding fragments of VP1 and its C terminus were respectively cloned into prokaryotic expression vector for prokaryotic expression and the reactionogenicity was detected. The purified fusion protein of FMDV VP1 and its C terminus of serotype C were used to construct the indirect ELISA method to detect positive sera of four serotypes A, O, C and Asia 1 of guinea pig and determine the cross reactivity of FMDV antibody of VP1 and its C terminus of serotype C with other three serotypes. [ Result] The recombinant prokaryotic expression plasmids of PPRO-CVP1 and pPRO-CVPlc were constructed, FMDV VP1 and its C terminus of serotype C were expressed in high level, and the molecular weight of target proteins was 33 kD and 20 kD respectively. Western blot result showed that the fusion protein of VP1 and its C terminus could react with the positive sera of guinea pig of the same serotype. ELISA results revealed that VP1 and its C terminus of serotype C are type-specific and no cross-reactivities were shown between guinea pig positive sera of FMDV of serotype C with the other three serotypes, and the C terminus showed better type-specificity. [ Conclusion] FMDV specific antigen of serotype C was obtained.

No DCX-positive neurogenesis in the cerebral cortex of the adult primate

Whether endogenous neurogenesis occurs in the adult cortex remains controversial.An increasing number of reports suggest that doublecortin(DCX)-positive neurogenesis persists in the adult primate cortex,attracting enormous attention worldwide.In this study,different DCX antibodies were used together with NeuN antibodies in immunohistochemistry and western blot assays using adjacent cortical sections from adult monkeys.Antibody adsorption,antigen binding,primary antibody omission and antibody-free experiments were used to assess specificity of the signals.We found either strong fluorescent signals,medium-weak intensity signals in some cells,weak signals in a few perikarya or near complete lack of labeling in adjacent cortical sections incubated with the various DCX antibodies.The putative DCX-positive cells in the cortex were also positive for NeuN,a specific marker of mature neurons.However,further experiments showed that most of these signals were either the result of antibody cross reactivity,the non-specificity of secondary antibodies or tissue autofluorescence.No confirmed DCX-positive cells were detected in the adult macaque cortex by immunofluorescence.Our findings show that DCX-positive neurogenesis does not occur in the cerebral cortex of adult primates,and that false-positive signals(artefacts)are caused by antibody cross reactivity and autofluorescence.The experimental protocols were approved by the Institutional Animal Care and Use Committee of the Institute of Neuroscience,Beijing,China(approval No.IACUC-AMMS-2014-501).

The cross-reactivity of I-Ag7 and I-Ad tetramers

To investigate the cross reactivity between glutamic acid decarboxylase (GAD) I A g7 and I A d tetramer in diabetes prone non obese diabetic (NOD) mice (I A g7 ) and diabetes free Balb/c mice (I A d) Methods Two GAD peptide I A g7 and I A d tetramers were generated and compared for phenotype and function of sorted GAD peptide I A g7 and I A d tetramer positive (tet +) T cells Results The cross reactivity is shown in either tetramer positive percentage or tetramer staining intensity The NOD and Balb/c derived tet + T cells were able to be cross stained by GAD peptide I A g7 and I A d tetramers, and responded to both irradiated NOD and Balb/c splenotyes under stimulation by synthetic and recombinant GAD peptides Conclusion Although I A g7 and I A d are closely related in biochemical and biological aspects, their most notable difference is the presence or absence of a negatively charged residue at position β57 that links to insulin dependent diabetes mellitus

Isolation and specific detection of two major schistosoma gut-associated circulating antigens

Objectives To investigate the nature of the common epitopes of Schistosoma japonicum (S. japonicum) circulating anodic (CAA) and circulating cathodic antigen (CCA) and to try to obtain sufficient purified material to set up a standard series for quantitative determinations.Methods Isolation of the two worm fractions from a trichloroacetic acid (TCA) soluble preparation of S. japonicum adult worm antigen (AWAj-TCA) via Mono-Q anion exchange chromatography was performed and analysis of specific reactivity of the eluted fractions was done by antigen-capture Enzyme Linked Immuno Sorbent Assay (ELISA) specific for CAA or CCA with reference to affinity purified preparations of S. mansoni CAA and CCA. Results When an ionic strength gradient was used, CCA was eluted in two major peaks, an unbound fraction CCA-1, and a major bound fraction, CCA-2. Two additional minor peaks, CCA-3 and CCA-4, were eluted at higher ionic strengths. CAA was only detected in the bound fraction, partly overlapping with CCA-3. In the CCA-1 and CCA-2 fractions, reactivity was only found in the antigen-capture ELISA using anti-CCA McAbs both for capture and detection. The CAA fraction was predominantly found to be positive in the antigen-capture ELISA using anti-CAA McAbs both for capture and detection. However, in ELISA using combined anti-CCA and anti-CAA McAbs for capture and detection, this fraction showed some reactivity.Conclusion The two CCA fractions contain molecules which bear at least two CCA-epitopes; the CAA fraction contains molecules which contain at least two CAA-epitopes, and one CCA-epitope.