Significant Increase In Titer Research Articles

The results of vaccination against novel coronavirus infection in adolescents with allergic diseases

Novel coronavirus infection requires analyzing its course in patients with allergic diseases. Patients with atopic allergic diseases remain insufficiently studied with regard to the peculiarities of the course of both the underlying allergic disease and infectious processes caused by viruses and bacteria. Epithelial cells in bronchial asthma do not respond sufficiently to interferons, suggesting that SARS-CoV-2 infection may suppress spontaneous upregulation of angiotensin-converting enzyme expression, which ultimately reduces disease severity, but at the same time makes patients with allergic atopic diseases susceptible to other viral infections. The results obtained indicate statistically significant differences in the formation of anti-RBD IgG antibodies to SARS-CoV-2 between the group of adolescents with bronchial asthma vaccinated against a new coronavirus infection and those not vaccinated against it. During the follow-up period after 6 months, a statistically significant increase in anti-RBD IgG titer to SARS-CoV-2 due to novel coronavirus infection was observed among the unimmunized children. Clinical parameters indicated a favorable course of atopic process and control of bronchial asthma exacerbations in adolescents who received vaccination against both new coronavirus infection and influenza, while those who did not receive vaccination against these viral infections had bronchial asthma exacerbations due to respiratory infection. Also among patients with bronchial asthma who received influenza vaccination, there were no cases of influenza A and bronchial asthma exacerbations due to respiratory infections. In this regard, influenza vaccination is an important intervention to maintain control of asthma exacerbations. It is noteworthy that no new coronavirus infection was reported among vaccinated adolescents within a year after immunization. At the same time, 6 months after vaccination against a new coronavirus infection, we observed a statistically significant increase in antibody levels in unvaccinated adolescents, indicating the presence of high viral neutralizing activity. Vaccination against novel coronavirus infection in patients with bronchial asthma may be considered a possibility.

Potential benefits of advanced chelate-based trace minerals in improving bone mineralization, antioxidant status, immunity, and gene expression modulation in heat-stressed broilers.

Organic sources of trace minerals (TM) in broiler diets are more bioavailable and stable than inorganic sources, making them particularly beneficial during challenging periods such as heat stress (HS) conditions. A 42-d study investigated the effects of using advanced chelate technology-based TM (ACTM) or adding varying amounts of ACTM to broiler diets during HS conditions. The study involved 672 male broiler chickens in 7 treatment groups, including a thermoneutral control (TNC) group and six HS treatments. There were 8 replicate pens per treatment and 12 birds per replicate. The six HS treatments included birds exposed to a cyclic HS environment (34°C) for 8 h and were as follows: HSC, which consisted of the same basal diet with the recommended ITM levels; ACTM50 and ACTM100, which replaced the basal diet with 50% and 100% ACTM instead of ITM; ITM+ACTM12.5 and ITM+ACTM25, which involved adding extra ACTM to the ITM basal diet at 12.5% and 25%, respectively; and ITM125, which used 125% of the recommended levels of ITM in the basal diet. Compared with the HSC treatment, the TNC, ACTM100, and ITM+ACTM25 treatments resulted in increased (P < 0.05) body weight; tibia weight; tibia ash, phosphorus, iron, and manganese contents; secondary antibody titers; and serum TAC and SOD values but decreased (P < 0.05) serum MDA concentrations and the expression levels of the hepatic genes IL-1β, IL-6, and INF-γ. The TNC and ACTM100 groups also showed greater (P < 0.05) feed efficiency, tibia length, tibia zinc content, and hepatic SOD1 expression but exhibited reduced (P < 0.05) hepatic NF-kB expression. Significant increases (P < 0.05) in primary anti-NDV titers, serum GPx1 activity, and Nrf2 and GPx1 gene expression levels were also detected in the ACTM100, ITM+ACTM12.5, and ITM+ACTM25 groups. In conclusion, the findings suggest that replacing ITM with ACTM or adding ACTM to ITM diets, especially at a 25% higher dose, can effectively protect broilers from heat stress by promoting growth, reducing inflammation, and increasing the expression of antioxidant proteins.

Antibody Response of Mice to Bali Isolate of Canine Parvovirus Propagated in Madin-Darby Canine Kidney Cell Culture

Canine parvovirus (CPV) infection is still common among dogs, leading to severe disease with high mortality. The potential of a local isolate of CPV as an effective vaccine to prevent the disease warrants investigation. This study aimed to determine the antibody response in mice against a Bali isolate of CPV propagated in the Madin-Darby Canine Kidney (MDCK) cell culture. The virus was purified using polyethylene glycol (PEG)-6000 and mixed with an Aluminum hydroxide adjuvant. Fifteen 7-week female mice were divided into three treatment groups: treatment group 1 (PEG-purified virus and Adjuvant), treatment group 2 (crude unpurified virus and adjuvant), and treatment group 3 (adjuvant without virus), with five replicates per group. The Bali isolate of CPV was successfully replicated in MDCK cells, achieving a titer of 210-211 hemagglutination (HA) units after eight serial passages through the cell culture. The virus was confirmed as CPV by immunocytochemistry test using a monoclonal antibody and hemagglutination inhibition (HI) test using chicken anti-CPV polyclonal antibody. Following the first immunization, the antibody endpoint titer in mice immunized with PEG-purified CPV (5.6) was significantly higher than those immunized with crude unpurified CPV (4.2) and adjuvant without CPV (1.4). Similarly, after the second immunization, the antibody endpoint titer in mice immunized with PEG-purified CPV (7.6) also remained significantly higher than those immunized with crude unpurified CPV (6.4) and adjuvant without CPV (0.8). Significant increases in antibody endpoint titer were observed after the second immunization in mice immunized with PEG-purified CPV and crude unpurified CPV, but not in those given adjuvant without CPV. The Bali isolate of CPV propagated in MDCK cell culture induced a robust antibody response in mice, suggesting it’s a potential as an alternative vaccine candidate for preventing CPV infection in dogs.

Immune Response after Vaccination against Tick-Borne Encephalitis Virus (TBEV) in Horses.

(1) Background: Horses infected by a tick-borne encephalitis virus (TBEV) can develop clinically apparent infections. In humans, vaccination is the most effective preventive measure, while a vaccine is not available for horses. The objective of this study was to describe the immune response in horses after a TBEV vaccination with a human vaccine. (2) Materials and Methods: Seven healthy horses were randomised to a treatment or a control group in a stratified fashion based on TBEV-IgG concentrations on day -4. The treatment group (n = 4) was intramuscularly vaccinated using an inactivated human TBEV vaccine on days 0 and 28; the control group (n = 3) did not receive an injection. A clinical examination and blood sampling were performed on day -4, 0, 2, 4, 6, 8, 10, 14, 28, 30, 32, 34, 36, 38, 43, 56, 84, and 373. A linear mixed model analysis was used to compare IgG and IgM concentrations, neutralising antibody (nAb) titres, leucocyte count, serum amyloid A (SAA), and fibrinogen and globulin concentrations between the groups and time points. (3) Results: The clinical examination was normal in all horses at all time points. There were no significant changes in SAA, globulin, and fibrinogen concentrations and leucocyte count between the groups or time points (all p > 0.05). There was no significant increase in IgG, IgM, or nAb titres in the control group over time (all p > 0.05). In the vaccination group, there was a significant increase in IgG concentration and nAb titres after the second vaccination (p < 0.0001). There was no significant increase in IgM antibodies after the TBEV vaccination (all p > 0.05). One horse in the vaccination group had an IgM concentration above the laboratory reference on day 10. (4) Conclusions: The human TBEV vaccine did not have side effects when used in healthy horses in this study. A significant rise in TBEV-specific IgG antibodies and nAbs after the second vaccination was observed. However, IgG and nAb titres have been shown to decrease within 1 year after vaccination. The results of this study indicate that a vaccination with a human vaccine only induces a mild rise in IgM antibodies and only in previously naive horses. With no significant changes to inflammatory parameters in the vaccinated horses, it remains unclear whether vaccination with the human vaccine leads to protective immunity.

Validation of a focus reduction neutralization test (FRNT) to rapidly titrate human SARS-CoV-2 neutralizing antibodies by using the CTL Immunospot S6 universal analyzer

In this paper we describe the validation of a focus reduction neutralization test (FRNT) to quantitate human SARS-CoV-2 neutralizing antibodies by using the CTL Immunospot S6 Universal Analyzer. We employed a previously published protocol and compared its performances to a well-established and traditional serum-neutralization assay (SN). To assess diagnostic sensitivity, a total number of 201 human sera positive by SN for SARS-CoV-2 NAbs were processed: 196/201 tested positive by FRNT50 (97.51 %). A diagnostic specificity of 100 % was obtained by evaluating 206 negative serum samples. Repeatability of the test was evaluated by determining the intra and inter-assay coefficient of variation (CV). A standard deviation of 0.83 and a CV of 13 % were evidenced demonstrating an acceptable reproducibility of the assay. Moreover, a Cohen's Kappa of 0.975 was obtained proving an extremely high level of agreement between the FRNT protocol and the SN. Despite an acceptable correlation between methods (p < 0.05), FRNT demonstrated a statistically significant increase in NAbs titres compared to SN as well as higher data variability and asymmetry. These discrepancies could be attributed to FRNT sensitivity or most probably to the subjective interpretation of SN, although this aspect needs to be further investigated with a more representative number of samples.Basing on our results, it is reasonable to replace the SN with the FRNT assay as, with this, fast processing time (less than 2 days) and operator bias-free results registrations are guaranteed.

Immunogenicity of the Inactivated SARS-CoV-2 Vaccine (BBIBPCorV) in Hemodialysis Patients: A Case-Control Study

Background: Studies have shown that immune responses to COVID-19 vaccines are impaired in dialysis patients, which may affect their immunity to vaccines. Therefore, this study aimed to evaluate SARS-COV-2 neutralizing antibodies in hemodialysis patients for 2 and 6 weeks after receiving inactivated Sinopharm vaccine. Method: In this study, 172 people were divided into two groups. The first group included 108 hemodialysis patients, while the second group included 64 health workers as a control group. To evaluate SARS-COV-2 neutralizing antibody titers, peripheral blood samples were collected from all participants 2 and 6 weeks after receiving the second dose of the Sinopharm vaccine. Samples were centrifuged, and the neutralizing antibody against the receptor-binding domain (RBD) was determined using the indirect ELISA technique. Results: Hemodialysis patients had lower IgG-neutralizing antibody titers than the control group (P &lt;0.001). The titers of SARS-COV-2 neutralizing antibodies were not significantly different at two weeks compared to six weeks after vaccination (P=0.9204). Our findings showed a significant increase in titers of IgGneutralizing antibodies after vaccination in people with a history of COVID-19 (P=0.002). The seropositivity rate for neutralizing antibodies against RBD was significantly different between seropositive (immune) and seronegative (non-immune) patients six weeks after vaccination (P=0.022). Conclusion: The titers of neutralizing antibodies against SARS-COV-2 were lower in hemodialysis patients than in healthy individuals. This is probably due to the poor immune system. However, patients who received two doses of inactivated Sinopharm vaccine showed a higher antibody titer six weeks after vaccination.

Valorisation of Spent Yeast Fermentation Media through Compositional-Analysis-Directed Supplementation

Spent fermentation media from bioprocessing represent a significant waste stream, and interest in recycling them as part of the developing circular bioeconomy is growing. The potential to reuse yeast spent culture media (YSM) to feed secondary bacterial fermentations producing recombinant protein was investigated in this study. Elemental and amino acid compositional analysis using inductively coupled plasma mass spectrometry (ICP-MS) and LC-MS/MS identified significant differences in the concentrations of 6 elements and 18/20 amino acids in YSM compared with rich microbiological media (LB). Restoration of levels of magnesium and sodium through addition of their salts and amino acids from tryptone supplementation led to the expression of equivalent titres of recombinant proteins by E. coli (0.275 g/L), compared to that in LB media (0.296 g/L) and BMMY media (0.294 g/L) in shake flask culture. When this supplementation strategy was employed in a bioreactor system, we observed a significant increase in recombinant protein titre using the supplemented YSM (2.29 (±0.02) g/L) over that produced using LB media (1.29 (±0.09) g/L). This study demonstrates through highly sensitive compositional analysis and identification of supplementation strategies the potential to valorise spent media from yeast fermentations that underpin industrial processes of significant scale, creating a circular approach to waste stream management.

The enhancement of M13 phage titration by optimizing the origin of replication.

M13KO7, a modified M13 phage variant, carries the p15A replication origin and Tn903 kanamycin resistance gene. This study aimed to optimize M13KO7's replication by substituting the p15A origin with the higher-copy pMB1 origin (500-700 copy numbers). A 6431-nucleotide fragment from the M13KO7 plasmid lacking the p15A replication origin and kanamycin resistance gene was amplified using a long polymerase chain reaction (PCR). The modified M13AMB1 plasmid was created by adding adenine to the 3' ends of this fragment and ligating it to the pMB1-containing fragment using T/A cloning. Afterward, to prepare the phage, pM13AMB1 was transformed into E. coli TG1 bacteria, and then, using the PEG-NaCl precipitation, the modified phage was propagated. The modified phage titer was determined utilizing the serial dilution and the qPCR methods, compared with the M13KO7 phage. The results showed that in the serial dilution method, the titers of modified phage and M13KO7 phage were 4.8 × 1014 and 7 × 1012 pfu/mL, respectively. Besides, the phage titer calculated by the qPCR method for the modified phage was equal to 1.3 × 109 pfu/mL, whereas it was 4.08 × 108 pfu/mL for the M13KO7 phage. This study provides evidence that replication origin replacement led to a significant increase in phage titers. It highlights the importance of replication optimization for molecular biology applications.

Modifications of the 5' region of the CASPONTM tag's mRNA further enhance soluble recombinant protein production in Escherichia coli.

Escherichia coli is one of the most commonly used host organisms for the production of biopharmaceuticals, as it allows for cost-efficient and fast recombinant protein expression. However, challenging proteins are often produced with low titres or as inclusion bodies, and the manufacturing process needs to be developed individually for each protein. Recently, we developed the CASPONTM technology, a generic fusion tag-based platform process for high-titer soluble expression including a standardized downstream processing and highly specific enzymatic cleavage of the fusion tag. To assess potential strategies for further improvement of the N-terminally fused CASPONTM tag, we modified the 5'UTR and 5' region of the tag-coding mRNA to optimize the ribosome-mRNA interactions. In the present work, we found that by modifying the 5'UTR sequence of a pET30acer plasmid-based system, expression of the fusion protein CASPONTM-tumour necrosis factor α was altered in laboratory-scale carbon-limited fed-batch cultivations, but no significant increase in expression titre was achieved. Translation efficiency was highest for a construct carrying an expression enhancer element and additionally possessing a very favourable interaction energy between ribosome and mRNA (∆Gtotal). However, a construct with comparatively low transcriptional efficiency, which lacked the expression enhancer sequence and carried the most favourable ∆Gtotal tested, led to the highest recombinant protein formation alongside the reference pET30a construct. Furthermore, we found, that by introducing synonymous mutations within the nucleotide sequence of the T7AC element of the CASPONTM tag, utilizing a combination of rare and non-rare codons, the free folding energy of the nucleotides at the 5' end (-4 to + 37) of the transcript encoding the CASPONTM tag increased by 6kcal/mol. Surprisingly, this new T7ACrare variant led to improved recombinant protein titres by 1.3-fold up to 5.3-fold, shown with three industry-relevant proteins in lab-scale carbon limited fed-batch fermentations under industrially relevant conditions. This study reveals some of the complex interdependencies between the ribosome and mRNA that govern recombinant protein expression. By modifying the 5'UTR to obtain an optimized interaction energy between the mRNA and the ribosome (ΔGtotal), transcript levels were changed, highlighting the different translation efficiencies of individual transcripts. It was shown that the highest recombinant titre was not obtained by the construct with the most efficient translation but by a construct with a generally high transcript amount coupled with a favourable ΔGtotal. Furthermore, an unexpectedly high potential to enhance expression by introducing silent mutations including multiple rare codons into the 5'end of the CAPONTM tag's mRNA was identified. Although the titres of the fusion proteins were dramatically increased, no formation of inclusion bodies or negative impact on cell growth was observed. We hypothesize that the drastic increase in titre is most likely caused by better ribosomal binding site accessibility. Our study, which demonstrates the influence of changes in ribosome-mRNA interactions on protein expression under industrially relevant production conditions, opens the door to the applicability of the new T7ACrare tag in biopharmaceutical industry using the CASPONTM platform process.

Enhanced baculoviral virulence by suppressing the degradation of an insect immune resolvin, epoxyoctadecamonoenoic acid, in three lepidopteran insects

Epoxyoctadecamonoenoic acids (EpOMEs) are produced from linoleic acid by a cytochrome P450 monooxygenase (CYP) and play a crucial role in terminating excessive and unnecessary immune responses during the late infection stage in insects. This suggests that an increase in the EpOME level may enhance the virulence of insect pathogens against pests. This study tested this hypothesis using a specific inhibitor against soluble epoxide hydrolase (sEH) to degrade EpOMEs, which leads to elevated endogenous EpOME levels. A baculovirus, Autographa californica multiple nucleopolyhedrovirus (AcMNPV), was used to infect three different lepidopteran insects (Spodoptera exigua, Maruca vitrata, and Plutella xylostella) by oral feeding or hemocoelic injection treatments. Within one hour, the viral infection induced the expression of three different phospholipase A2 (PLA2) genes and, after 12 h, up-regulated the expressions of CYP and sEH genes in Spodopera exigua. As expected, AcMNPV virulence was suppressed by the addition of arachidonic acid (a catalytic product of PLA2) but was enhanced by the addition of either of the EpOME regioisomers. In addition, treatment with a specific sEH inhibitor (AUDA) increased AcMNPV virulence against three different lepidopteran insects, presumably by increasing endogenous EpOME levels. This enhanced effect of EpOMEs on virulence was further supported by specific RNA interference (RNAi), in which RNAi specific to CYP expression decreased AcMNPV virulence while a specific RNAi against sEH expression significantly enhanced virulence. In response to AcMNPV infection, TUNEL assay results showed that S. exigua larvae exhibited apoptosis in the midgut, fat body, and epidermis. Inhibition of apoptosis by a pan-caspase inhibitor, Z-VAD-FMK, significantly increased virulence. Similarly, the addition of AUDA to the viral treatment suppressed the gene expression of five inducible caspases and cytochrome C to suppress apoptosis, which led to a significant increase in the tissue viral titers. These results indicate that EpOMEs play a role in terminating excessive and unnecessary immune responses against viral infection during the late stage by down-regulating antiviral apoptosis in lepidopteran insects.

Humoral immune response in people living with HIV after administration of SARS-CoV-2 vaccine CoronaVac or BNT162b2 or CoronaVac/BNT162b2 booster sequence: A cross-sectional study

BackgroundThe evidence of SARS-CoV-2 vaccine effectiveness in people living with HIV (PLWH) is limited. This study evaluated the humoral immune response to CoronaVac™ (virus inactivated) and BNT162b2 (mRNA- based) vaccines in PLWH and HIV-negative controls, with and without a booster sequence. MethodsWe conducted a cross-sectional study on PLWH and HIV-negative controls who received CoronaVac or BNT162b2, with a subgroup receiving a CoronaVac/BNT162b2 booster. Blood samples were collected 4–6 months after primary vaccination and tested for anti-SARS-CoV-2 protein S (aSAb) and neutralizing antibodies (NtAb) using validated assays. Immune response was evaluated by age, sex, previous COVID-19 history, and CD4 + cell count. FindingsOne hundred and eighty nine participants were enrolled with 161 (85%) being PLWH. Among participants without previous known COVID-19, median aSAb levels were significantly lower in PLWH who received CoronaVac compared to BNT162b2 (32 U/mL vs. 587 U/mL, p < 0.001), with similar results in HIV-negative controls. NtAb presence was also significantly lower after CoronaVac compared to BNT162b2 (30% vs. 93%, p < 0.001). The booster sequence group showed a significant increase in aSAb titers in both PLWH and HIV-negative controls (from 33 U/ml to 2500 U/ml, p < 0.001), and NtAb positivity increased from 20% to 95 % in PLWH, and 27% to 100% in HIV-negative controls. Prior COVID-19 led to significantly higher post-vaccine antibody titers particularly in the BNT162b2 group. PLWH with CD4 + count < 200 cells/mL showed a weaker immune response to both vaccines. InterpretationCoronaVac resulted in a weaker immune response in both PLWH and HIV-negative controls compared to BNT162b2, particularly in immunosuppressed PLWH without prior COVID-19. Hybrid immunity and heterologous booster vaccination increased antibody levels. FundingLocal funding.

Impact of Helicobacter pylori virulence on development of autoimmune thyroid diseases

Abstract Background: H. pylori infection has been linked in some controversial studies to the existence of extra-gastrointestinal disorders like autoimmune thyroid disease (AITD). Objective: The study aimed to investigate the impact of the H.pylori virulence factor on progression of autoimmune thyroid disease. Materials and Methods: The study carried out on 90 patients (male and female) with thyroid disorders, and 50 healthy individuals as a control group. Venous blood samples were drawn from all participants, serum obtained after centrifugation and kept in in a labeled Eppendorf tube then stored at -20°C till used in biochemical and immunological assays including: estimation of anti H.pylori IgG to investigate H.pylori infection and detection anti-cag-A IgG titer by ELISA method, while measurement of (T3), (T4), (TSH) and (ATPO) by (e601 cobas) automated immunoassay analyzer. Results: The results of the study recorded a significant increase in mean of TSH concentration (P &lt; 0.01) in patients group particularly in hypothyroidism patients, and a significant increase recorded (P &lt; 0.01) in patients according ATPO level in comparison to control group. On other hand the highest prevalence of H.pylori IgG positive (84%) occur in autoimmune thyroid diseases (AITD) group followed by (63%) for non-AITD while (56%) occur in control group. The results also recorded a highly significant increase in titer of H.pylori IgG (P &lt; 0.01) in patient group as compared to control group, the proportion of female was significantly higher in AITD group (75%), however, there was a significant increase (P &lt; 0.01) in the level of anti-cag IgG in patients as compared to control group, The ratio of infection with H.pylori was greater in the Hashimoto’s thyroiditis group (85.2%) than in the Graves’ disease group (82.4%). Conclusion: our findings state that H. pylori by expressing Cag A may have an impact on the development of autoimmunity thyroiditis.

Effect of acupuncture therapy on vaccine-induced immune response in d-galactose-induced aging rats

ObjectiveThis study aimed to explore whether acupuncture and moxibustion can enhance the immune response by increasing the expression of the endogenous adjuvant HSP70 mRNA. MethodForty Wistar rats were divided into four groups: model immune acupuncture group (A), model immune control group (B), normal immune acupuncture group (C), and normal immune control group (D). Model immune groups A and B were induced by injecting d-galactose for 6 weeks. Rats in groups A and C were then treated with low-frequency electroacupuncture (EA) at Zusanli (ST36), Guanyuan (CV4), and Baihui (GV20) and moxibustion for 3 weeks. Subsequently, all rats were observed for 2 more weeks. At the 12th week, diphtheria antitoxin titers were determined using the Vero cell trace neutralization method, CD4+T/CD8+T cell ratios in peripheral blood were examined by flow cytometry, and the relative expression of spleen cell HSP70 mRNA was measured by RT-PCR. ResultsCompared with the normal immune control, the diphtheria antitoxin titer, CD4+T/CD8+T cell ratio, and expression of spleen cell HSP70 mRNA significantly decreased in the model immune control group (P < 0.01). However, the model immune acupuncture group showed a significant increase in antitoxin titer (P < 0.01) and elevated CD4+T/CD8+T cell ratio and HSP70 mRNA expression (P < 0.05) after EA and moxibustion intervention. ConclusionAcupuncture and moxibustion may enhance the humoral immune response (diphtheria antitoxin titer) and cellular immune response (peripheral blood CD4+T/CD8+T cell ratio) by increasing the expression of the endogenous adjuvant HSP70 mRNA, suggesting that acupuncture may serve as a new vaccine adjuvant.

Development of a Tag/Catcher-mediated capsid virus-like particle vaccine presenting the conserved Neisseria gonorrhoeae SliC antigen that blocks human lysozyme.

Virus-like particles (VLPs) are promising nanotools for the development of subunit vaccines due to high immunogenicity and safety. Herein, we explored the versatile and effective Tag/Catcher-AP205 capsid VLP (cVLP) vaccine platform to address the urgent need for the development of an effective and safe vaccine against gonorrhea. The benefits of this clinically validated cVLP platform include its ability to facilitate unidirectional, high-density display of complex/full-length antigens through an effective split-protein Tag/Catcher conjugation system. To assess this modular approach for making cVLP vaccines, we used a conserved surface lipoprotein, SliC, that contributes to the Neisseria gonorrhoeae defense against human lysozyme, as a model antigen. This protein was genetically fused at the N- or C-terminus to the small peptide Tag enabling their conjugation to AP205 cVLP, displaying the complementary Catcher. We determined that SliC with the N-terminal SpyTag, N-SliC, retained lysozyme-blocking activity and could be displayed at high density on cVLPs without causing aggregation. In mice, the N-SliC-VLP vaccines, adjuvanted with AddaVax or CpG, induced significantly higher antibody titers compared to controls. In contrast, similar vaccine formulations containing monomeric SliC were non-immunogenic. Accordingly, sera from N-SliC-VLP-immunized mice also had significantly higher human complement-dependent serum bactericidal activity. Furthermore, the N-SliC-VLP vaccines administered subcutaneously with an intranasal boost elicited systemic and vaginal IgG and IgA, whereas subcutaneous delivery alone failed to induce vaginal IgA. The N-SliC-VLP with CpG (10 µg/dose) induced the most significant increase in total serum IgG and IgG3 titers, vaginal IgG and IgA, and bactericidal antibodies.

Levamisole Influences the Immune Response of Freshwater Prawn, &lt;i&gt;Macrobrachium rosenbergii&lt;/i&gt; and its Resistance to Nitrite Stress and &lt;i&gt;Aeromonas hydrophila&lt;/i&gt; Infection

The present study evaluated the effectiveness of dietary levamisole in the modulation of innate immunity and reducing the percent mortality against nitrite stress or Aeromonas hydrophila infection in giant freshwater prawn, Macrobrachium rosenbergii. Haemolymph agglutinin and total protein levels, lysozyme activity, phenoloxidase (PO) activity, total and differential haemocyte counts, induced nitrite stress and mortality (%) against Aeromonas hydrophila challenge were measured in sub-adult M. rosenbergii fed with diets containing levamisole at 0, 125, 250 and 500 mg/kg feed for 7 or 14 days. M. rosenbergii fed with a diet containing 250 mg levamisole/kg feed for 14 days showed significant (P&lt;0.05) increase in haemagglutination titre, PO activity, undifferentiated haemocyte count, resistance to nitrite stress and survival against A. hydrophila challenge. On the contrary, graded levels of levamisole feeding for 7 days failed to modulate most of the immune parameters or reduce the percent mortality against A. hydrophila challenge or nitrite stress. It is therefore concluded that administration of levamisole in the diet at 250 mg/kg feed for 14 days in sub-adult M. rosenbergii could enhance the immune ability and increase its resistance to A. hydrophila infection and nitrite stress.

Immunological aspects of additional revaccination of adolescents against whooping cough, diphtheria and tetanus

The epidemiological situation of whooping cough in many countries of the world shows an increase in the incidence, despite the high coverage of routine immunization of the child population, which indicates the need for additional booster doses in older age groups. Purpose. The study aims at a comparative analysis of the intensity of specific immunity against whooping cough, diphtheria and tetanus in adolescent children after revaccination with different types of vaccines. Material and methods. 121 adolescents received various preparations containing pertussis, diphtheria and tetanus as revaccination. Results. The use of the pertussis component in preparations for revaccination of adolescents, despite the fact that they initially have a certain level of seroprotection, is not accompanied by a significant increase in specific antibody titers. Some differences related to the types of drugs used: the AbDTP-M vaccine against AbDTP had the best seroprotection after 1 month, while at the same time, as after 12 months, this ratio reversed. Conclusion. The situation with the effectiveness of revaccination against tetanus and diphtheria with all the drugs used had a more predictable effect, which was reflected in a significant increase in the titer of specific antibodies after 1 month.

Safety and Immunogenicity of Inactivated Whole Virion COVID-19 Vaccine CoviVac in Clinical Trials in 18-60 and 60+ Age Cohorts.

We present the results of a randomized, double-blind, placebo-controlled, multi-center clinical trial phase I/II of the tolerability, safety, and immunogenicity of the inactivated whole virion concentrated purified coronavirus vaccine CoviVac in volunteers aged 18-60 and open multi-center comparative phase IIb clinical trial in volunteers aged 60 years and older. The safety of the vaccine was assessed in 400 volunteers in the 18-60 age cohort who received two doses of the vaccine (n = 300) or placebo (n = 100) and in 200 volunteers in 60+ age cohort all of whom received three doses of the vaccine. The studied vaccine has shown good tolerability and safety. No deaths, serious adverse events (AEs), or other significant AEs related to vaccination have been detected. The most common AE in vaccinated participants was pain at the injection site (p < 0.05). Immunogenicity assessment in stage 3 of Phase II was performed on 167 volunteers (122 vaccinated and 45 in Placebo Group) separately for the participants who were anti-SARS-CoV-2 nAB negative (69/122 in Vaccine Group and 28/45 in Placebo Group) or positive (53/122 in Vaccine Group and 17/45 in Placebo Group) at screening. On Day 42 after the 1st vaccination, the seroconversion rate in participants who were seronegative at screening was 86.9%, with the average geometric mean neutralizing antibody (nAB) titer of 1:20. A statistically significant (p < 0.05) increase in IFN-γ production by peptide-stimulated T-cells was observed at Days 14 and 21 after the 1st vaccination. In participants who were seropositive at screening but had nAB titers below 1:256, the rate of fourfold increase in nAB levels was 85.2%, while in the participants with nAB titers > 1:256, the rate of fourfold increase in nAB levels was below 45%; the participants who were seropositive at screening of the 2nd vaccination did not lead to a significant increase in nAB titers. In conclusion, inactivated vaccine CoviVac has shown good tolerability and safety, with over 85% NT seroconversion rates after complete vaccination course in participants who were seronegative at screening in both age groups: 18-60 and 60+. In participants who were seropositive at screening and had nAB titers below 1:256, a single vaccination led to a fourfold increase in nAB levels in 85.2% of cases. These findings indicate that CoviVac can be successfully used both for primary vaccination in a two-dose regimen and for booster vaccination as a single dose in individuals with reduced neutralizing antibody levels.

Highly efficient production of L-valine by multiplex metabolic engineering of Corynebacterium glutamicum

As a branched chain amino acid, L-valine is widely used in the medicine and feed sectors. In this study, a microbial cell factory for efficient production of L-valine was constructed by combining various metabolic engineering strategies. First, precursor supply for L-valine biosynthesis was enhanced by strengthening the glycolysis pathway and weakening the metabolic pathway of by-products. Subsequently, the key enzyme in the L-valine synthesis pathway, acetylhydroxylate synthase, was engineered by site-directed mutation to relieve the feedback inhibition of the engineered strain. Moreover, promoter engineering was used to optimize the gene expression level of key enzymes in L-valine biosynthetic pathway. Furthermore, cofactor engineering was adopted to change the cofactor preference of acetohydroxyacid isomeroreductase and branched-chain amino acid aminotransferase from NADPH to NADH. The engineered strain C. glutamicum K020 showed a significant increase in L-valine titer, yield and productivity in 5 L fed-batch bioreactor, up to 110 g/L, 0.51 g/g and 2.29 g/(L‧h), respectively.

Continuous precipitation-filtration process for initial capture of a monoclonal antibody product using a four-stage countercurrent hollow fiber membrane washing step.

The significant increase in product titers, coupled with the growing focus on continuous bioprocessing, has renewed interest in using precipitation as a low-cost alternative to Protein A chromatography for the primary capture of monoclonal antibody (mAb) products. In this work, a commercially relevant mAb was purified from clarified cell culture fluid using a tubular flow precipitation reactor with dewatering and washing provided by tangential flow microfiltration. The particle morphology was evaluated using an inline high-resolution optical probe, providing quantitative data on the particle size distribution throughout the precipitation process. Data were obtained in both a lab-built 2-stage countercurrent washing system and a commercial countercurrent contacting skid that provided 4 stages of continuous washing. The processes were operated continuously for 2 h with overall mAb yield of 92 ± 3% and DNA removal of nearly 3 logs in the 4-stage system. The high DNA clearance was achieved by selective redissolution of the mAb using a low pH acetate buffer. Host cell protein clearance was 0.59 ± 0.08 logs, comparable to that based on model predictions. The process mass intensity was slightly better than typical Protein A processes and could be significantly improved by preconcentration of the antibody feed material.

Differences between DNA vaccine and single-cycle viral vaccine in the ability of cross-protection against viral hemorrhagic septicemia virus (VHSV) and infectious hematopoietic necrosis virus (IHNV)

Vaccination procedures can be stressful for fish and can bring severe side effects. Therefore, vaccines that can minimize the number of administrations and maximize cross-protection against multiple serotypes, genotypes, or even different species would be highly advantageous. In the present study, we investigated the cross-protective ability of two types of vaccines – viral hemorrhagic septicemia virus (VHSV) G protein-expressing DNA vaccine and G gene-deleted single-cycle VHSV genotype IVa (rVHSV-ΔG) vaccine - against both VHSV genotype Ia and infectious hematopoietic necrosis virus (IHNV) in rainbow trout (Oncorhynchus mykiss). The results showed that rainbow trout immunized with VHSV genotype Ia G gene- or IVa G gene-expressing DNA vaccine were significantly protected against VHSV genotype Ia, but were not protected against IHNV. In contrast to the DNA vaccine, the single-cycle VHSV IVa vaccine induced significant protection against not only VHSV Ia but also IHNV. Considering no significant increase in ELISA titer and serum neutralization activity against IHNV in fish immunized with single-cycle VHSV IVa, the protection might be independent of humoral adaptive immunity. The scarcity of cytotoxic T cell epitopes between VHSV and IHNV suggested that the possibility of involvement of cytotoxic T cell-mediated cellular adaptive immunity would be low. The role of trained immunity (innate immune memory) in cross-protection should be further investigated.