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Estrada M, Zhu C, Bzami A, White JA, Lal M. Development of a quantitative ELISA for SARS-CoV-2 vaccine candidate, NDV-HXP-S, with CpG 1018® adjuvant. Hum Vaccin Immunother 2024; 20:2315709. [PMID: 38372198 PMCID: PMC10877971 DOI: 10.1080/21645515.2024.2315709] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Accepted: 02/05/2024] [Indexed: 02/20/2024] Open
Abstract
NDV-HXP-S is a Newcastle disease virus (NDV) vectored vaccine candidate which expresses the S-antigen of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This vaccine candidate is under evaluation in human clinical studies with and without cytosine phosphate guanine (CpG) 1018® adjuvant. Existing potency methods for NDV-HXP-S do not allow for quantification of the S-antigen when the adjuvant is present. To support evaluation of NDV-HXP-S with CpG 1018® adjuvant, an inhibition enzyme-linked immunosorbent assay (ELISA) was developed to allow for quantification and stability assessments of the vaccine. A pilot 6-month stability study was conducted on NDV-HXP-S vaccine with and without CpG 1018® adjuvant under refrigerated conditions (2°C to 8°C) and accelerated stability testing conditions (40°C). The vaccine was mixed with and without CpG 1018® adjuvant in saline and maintained S-antigen content at 2°C to 8°C for the entire 6-month period. Additionally, a pilot controlled temperature chain (CTC) stability study was conducted at the completion of the 6-month study and demonstrated the possibility for this vaccine candidate to attain CTC stability labeling.
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Bzami A, Zhu C, Estrada M, White JA, Lal M. Development of multidose thermotolerant formulations of a vector-based Covid-19 vaccine candidate, NDV-HXP-S in different product formats: Stability and preservative efficacy study. Vaccine X 2024; 20:100535. [PMID: 39189025 PMCID: PMC11345403 DOI: 10.1016/j.jvacx.2024.100535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2024] [Revised: 06/21/2024] [Accepted: 07/25/2024] [Indexed: 08/28/2024] Open
Abstract
Current lead coronavirus vaccines require continuous cold or ultra-cold storage from the manufacturing site to the field to maintain protective efficacy. Since cold chain capacity is limited and complex, logistics planning is crucial to limit vaccine wastage.[1] The restrictive storage concerns also make it difficult to share vaccines between public health departments and neighboring states, leading to increased vaccine wastage.[2] A Newcastle Disease Virus (NDV) vector-based severe acute respiratory syndrome coronavirus 2 (SARS CoV-2) vaccine candidate, NDV-HXP-S, offers a cost-effective alternative which aims to improve global access to SARS CoV-2 vaccines.[3] The NDV-HXP-S vaccine candidate can be mass-produced in chicken eggs and has demonstrated efficacy in preclinical studies, as well as acceptable safety and potent immunogenicity in clinical studies.[3,4-10] To further advance the NDV-HXP-S vaccine candidate, this manuscript describes work focused on the development of multidose thermotolerant vaccine formulations (i.e., those which would not require continuous extended refrigeration), making it convenient to use and store, and simplifying transport and distribution logistics, especially in outbreak settings. Liquid and lyophilized formulations for parenteral administration were rigorously screened for the vaccine formulation's ability to maintain S-antigen stability after exposure to temperature stress at 40 °C, 25 °C, and 2 °C to 8 °C storage for six months. Preservative efficacy was evaluated to enable a multidose liquid vaccine format as well as endotoxin testing in lyophilized formulations. Lead liquid vaccine formations were identified that were able to maintain S-antigen content at 2 °C to 8 °C and 25 °C storage for the entire six-month study. Lead lyophilized vaccine formulations were identified which were able to maintain S-antigen content for six months at 2 °C to 8 °C, 25 °C, and 40 °C. Both the liquid and lyophilized formulations identified are improved thermotolerant SARS-CoV-2 vaccine formulations.
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Manukyan H, Lal M, Zhu C, Singh O, Lin TL, Tritama E, Chumakov K, Lee SM, Laassri M. Application of MPBT Assay for Multiplex Determination of Infectious Titers and for Selection of the Optimal Formulation for the Trivalent Novel Oral Poliovirus Vaccine. Viruses 2024; 16:961. [PMID: 38932253 PMCID: PMC11209357 DOI: 10.3390/v16060961] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2024] [Revised: 06/11/2024] [Accepted: 06/12/2024] [Indexed: 06/28/2024] Open
Abstract
Recently, a multiplex PCR-based titration (MPBT) assay was developed for simultaneous determination of infectious titers of all three Sabin strains of the oral poliovirus vaccine (OPV) to replace the conventional CCID50 assay, which is both time-consuming and laborious. The MPBT assay was shown to be reproducible, robust and sensitive. The conventional and MPBT assays showed similar results and sensitivity. The MPBT assay can be completed in two to three days, instead of ten days for the conventional assay. To prevent attenuated vaccine strains of poliovirus from reversion to virulence, a novel, genetically stable OPV (nOPV) was developed by modifying the genomes of conventional Sabin strains used in OPV. In this work, we evaluated the MPBT assay as a rapid screening tool to support trivalent nOPV (tnOPV) formulation development by simultaneous titration of the three nOPV strains to confirm stability as needed, for the selection of the lead tnOPV formulation candidate. We first assessed the ability of the MPBT assay to discriminate a 0.5 log10 titer difference by titrating the two tnOPV samples (undiluted and threefold-diluted) on the same plate. Once the assay was shown to be discriminating, we then tested different formulations of tnOPV drug products (DPs) that were subjected to different exposure times at 37 °C (untreated group and treated groups: 2 and 7 days at 37 °C), and to three freeze and thaw (FT) cycles. Final confirmation of the down selected formulation candidates was achieved by performing the conventional CCID50 assay, comparing the stability of untreated and treated groups and FT stability testing on the top three candidates. The results showed that the MPBT assay generates similar titers as the conventional assay. By testing two trivalent samples in the same plate, the assay can differentiate a 0.5 log10 difference between the titers of the tested nOPV samples. Also, the assay was able to detect the gradual degradation of nOPV viruses with different formulation compositions and under different time/temperature conditions and freeze/thaw cycles. We found that there were three tnOPV formulations which met the stability criteria of less than 0.5 log10 loss after 2 days' exposure to 37 ℃ and after three FT cycles, maintaining the potency of all three serotypes in these formulations. The ability of the MPBT assay to titrate two tnOPV lots (six viruses) in the same plate makes it cheaper and gives it a higher throughput for rapid screening. The assay detected the gradual degradation of the tnOPV and was successful in the selection of optimal formulations for the tnOPV. The results demonstrated that the MPBT method can be used as a stability indicating assay to assess the thermal stability of the nOPV. It can be used for rapid virus titer determination during the vaccine manufacturing process, and in clinical trials. The MPBT assay can be automated and applied for other viruses, including those with no cytopathic effect.
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Chetia P, Bharadwaj C, Purbey R, Yadav A, Lal M, Rajulu AV, Sadiku ER, Selvam SP, Jarugala J. Influence of silylated nano cellulose reinforcement on the mechanical, water resistance, thermal, morphological and antibacterial properties of soy protein isolate (SPI)-based composite films. Int J Biol Macromol 2023; 242:124861. [PMID: 37192712 DOI: 10.1016/j.ijbiomac.2023.124861] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Revised: 04/27/2023] [Accepted: 05/10/2023] [Indexed: 05/18/2023]
Abstract
The aim of this research work is to improve the mechanical and water-resistance properties of soy protein isolate (SPI) biofilm. In this work, 3-aminopropyltriethoxysilane (APTES) coupling agent modified nanocellulose was introduced into the SPI matrix in the presence of citric acid cross-linker. The presence of amino groups in APTES facilitated to form cross-linked structures with soy protein. The incorporation of a citric acid cross-linker made the cross-linking process more productive, and the surface smoothness of the film was confirmed by a Scanning Electron Microscope (FE-SEM). From the study of the mechanical and thermal properties and water resistance of the film, it was confirmed that the results were highly satisfactory for the modified nanocellulose incorporated film compared to the non-modified one. Additionally, coating of citral essential oil onto SPI nanocomposite film displayed antimicrobial properties due to the presence of various phenolic groups in the citral oil. The Tensile Strength and Young's Modulus of silane-modified nanocellulose containing film were enhanced by ~119 % and ~ 112 %, respectively on incorporation of 1 % APTES-modified nanocellulose. Consequently, this work is expected to offer an effective way for silylated nano-cellulose reinforcing soy protein isolate (SPI) based bio nanocomposite films for packaging applications. As an example, we have demonstrated one of the application as wrapping films for packing black grapes.
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Duc Dang A, Dinh Vu T, Hai Vu H, Thanh Ta V, Thi Van Pham A, Thi Ngoc Dang M, Van Le B, Huu Duong T, Van Nguyen D, Lawpoolsri S, Chinwangso P, McLellan JS, Hsieh CL, Garcia-Sastre A, Palese P, Sun W, Martinez JL, Gonzalez-Dominguez I, Slamanig S, Manuel Carreño J, Tcheou J, Krammer F, Raskin A, Minh Vu H, Cong Tran T, Mai Nguyen H, Mercer LD, Raghunandan R, Lal M, White JA, Hjorth R, Innis BL, Scharf R. Safety and immunogenicity of an egg-based inactivated Newcastle disease virus vaccine expressing SARS-CoV-2 spike: Interim results of a randomized, placebo-controlled, phase 1/2 trial in Vietnam. Vaccine 2022; 40:3621-3632. [PMID: 35577631 PMCID: PMC9106407 DOI: 10.1016/j.vaccine.2022.04.078] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Revised: 04/03/2022] [Accepted: 04/25/2022] [Indexed: 01/13/2023]
Abstract
Production of affordable coronavirus disease 2019 (COVID-19) vaccines in low- and middle-income countries is needed. NDV-HXP-S is an inactivated egg-based Newcastle disease virus (NDV) vaccine expressing the spike protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Wuhan-Hu-1. The spike protein was stabilized and incorporated into NDV virions by removing the polybasic furin cleavage site, introducing the transmembrane domain and cytoplasmic tail of the fusion protein of NDV, and introducing six prolines for stabilization in the prefusion state. Vaccine production and clinical development was initiated in Vietnam, Thailand, and Brazil. Here the interim results from the first stage of the randomized, dose-escalation, observer-blind, placebo-controlled, phase 1/2 trial conducted at the Hanoi Medical University (Vietnam) are presented. Healthy adults aged 18-59 years, non-pregnant, and with self-reported negative history for SARS-CoV-2 infection were eligible. Participants were randomized to receive one of five treatments by intramuscular injection twice, 28 days apart: 1 μg +/- CpG1018 (a toll-like receptor 9 agonist), 3 μg alone, 10 μg alone, or placebo. Participants and personnel assessing outcomes were masked to treatment. The primary outcomes were solicited adverse events (AEs) during 7 days and subject-reported AEs during 28 days after each vaccination. Investigators further reviewed subject-reported AEs. Secondary outcomes were immunogenicity measures (anti-spike immunoglobulin G [IgG] and pseudotyped virus neutralization). This interim analysis assessed safety 56 days after first vaccination (day 57) in treatment-exposed individuals and immunogenicity through 14 days after second vaccination (day 43) per protocol. Between March 15 and April 23, 2021, 224 individuals were screened and 120 were enrolled (25 per group for active vaccination and 20 for placebo). All subjects received two doses. The most common solicited AEs among those receiving active vaccine or placebo were all predominantly mild and included injection site pain or tenderness (<58%), fatigue or malaise (<22%), headache (<21%), and myalgia (<14%). No higher proportion of the solicited AEs were observed for any group of active vaccine. The proportion reporting vaccine-related AEs during the 28 days after either vaccination ranged from 4% to 8% among vaccine groups and was 5% in controls. No vaccine-related serious adverse event occurred. The immune response in the 10 μg formulation group was highest, followed by 1 μg + CpG1018, 3 μg, and 1 μg formulations. Fourteen days after the second vaccination, the geometric mean concentrations (GMC) of 50% neutralizing antibody against the homologous Wuhan-Hu-1 pseudovirus ranged from 56.07 IU/mL (1 μg, 95% CI 37.01, 84.94) to 246.19 IU/mL (10 μg, 95% CI 151.97, 398.82), with 84% to 96% of vaccine groups attaining a ≥ 4-fold increase over baseline. This was compared to a panel of human convalescent sera (N = 29, 72.93 95% CI 33.00-161.14). Live virus neutralization to the B.1.617.2 (Delta) variant of concern was reduced but in line with observations for vaccines currently in use. Since the adjuvant has shown modest benefit, GMC ratio of 2.56 (95% CI, 1.4-4.6) for 1 μg +/- CpG1018, a decision was made not to continue studying it with this vaccine. NDV-HXP-S had an acceptable safety profile and potent immunogenicity. The 3 μg dose was advanced to phase 2 along with a 6 μg dose. The 10 μg dose was not selected for evaluation in phase 2 due to potential impact on manufacturing capacity. ClinicalTrials.gov NCT04830800.
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Pitisuttithum P, Luvira V, Lawpoolsri S, Muangnoicharoen S, Kamolratanakul S, Sivakorn C, Narakorn P, Surichan S, Prangpratanporn S, Puksuriwong S, Lamola S, Mercer LD, Raghunandan R, Sun W, Liu Y, Carreño JM, Scharf R, Phumratanaprapin W, Amanat F, Gagnon L, Hsieh CL, Kaweepornpoj R, Khan S, Lal M, McCroskery S, McLellan J, Mena I, Meseck M, Phonrat B, Sabmee Y, Singchareon R, Slamanig S, Suthepakul N, Tcheou J, Thantamnu N, Theerasurakarn S, Tran S, Vilasmongkolchai T, White JA, Bhardwaj N, Garcia-Sastre A, Palese P, Krammer F, Poopipatpol K, Wirachwong P, Hjorth R, Innis BL. Safety and immunogenicity of an inactivated recombinant Newcastle disease virus vaccine expressing SARS-CoV-2 spike: Interim results of a randomised, placebo-controlled, phase 1 trial. EClinicalMedicine 2022; 45:101323. [PMID: 35284808 PMCID: PMC8903824 DOI: 10.1016/j.eclinm.2022.101323] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Revised: 01/24/2022] [Accepted: 02/11/2022] [Indexed: 12/03/2022] Open
Abstract
Background Production of affordable coronavirus disease 2019 (COVID-19) vaccines in low- and middle-income countries is needed. NDV-HXP-S is an inactivated egg-based recombinant Newcastle disease virus vaccine expressing the spike (S) protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). It's being developed by public sector manufacturers in Thailand, Vietnam, and Brazil; herein are initial results from Thailand. Methods This phase 1 stage of a randomised, dose-escalation, observer-blind, placebo-controlled, phase 1/2 trial was conducted at the Vaccine Trial Centre, Mahidol University (Bangkok). Healthy males and non-pregnant females, aged 18-59 years and negative for SARS-CoV-2 antibodies, were eligible. Participants were randomised to receive one of six treatments by intramuscular injection twice, 28 days apart: 1 µg, 1 µg+CpG1018 (a toll-like receptor 9 agonist), 3 µg, 3 µg+CpG1018, 10 µg, or placebo. Participants and personnel assessing outcomes were masked to treatment. The primary outcomes were solicited and spontaneously reported adverse events (AEs) during 7 and 28 days after each vaccination, respectively. Secondary outcomes were immunogenicity measures (anti-S IgG and pseudotyped virus neutralisation). An interim analysis assessed safety at day 57 in treatment-exposed individuals and immunogenicity through day 43 per protocol. ClinicalTrials.gov (NCT04764422). Findings Between March 20 and April 23, 2021, 377 individuals were screened and 210 were enroled (35 per group); all received dose one; five missed dose two. The most common solicited AEs among vaccinees, all predominantly mild, were injection site pain (<63%), fatigue (<35%), headache (<32%), and myalgia (<32%). The proportion reporting a vaccine-related AE ranged from 5·7% to 17·1% among vaccine groups and was 2·9% in controls; there was no vaccine-related serious adverse event. The 10 µg formulation's immunogenicity ranked best, followed by 3 µg+CpG1018, 3 µg, 1 µg+CpG1018, and 1 µg formulations. On day 43, the geometric mean concentrations of 50% neutralising antibody ranged from 122·23 international units per mL (IU/mL; 1 µg, 95% confidence interval (CI) 86·40-172·91) to 474·35 IU/mL (10 µg, 95% CI 320·90-701·19), with 93·9% to 100% of vaccine groups attaining a ≥ 4-fold increase over baseline. Interpretation NDV-HXP-S had an acceptable safety profile and potent immunogenicity. The 3 µg and 3 µg+CpG1018 formulations advanced to phase 2. Funding National Vaccine Institute (Thailand), National Research Council (Thailand), Bill & Melinda Gates Foundation, National Institutes of Health (USA).
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Pitisuttithum P, Luvira V, Lawpoolsri S, Muangnoicharoen S, Kamolratanakul S, Sivakorn C, Narakorn P, Surichan S, Prangpratanporn S, Puksuriwong S, Lamola S, Mercer LD, Raghunandan R, Sun W, Liu Y, Carreño JM, Scharf R, Phumratanaprapin W, Amanat F, Gagnon L, Hsieh CL, Kaweepornpoj R, Khan S, Lal M, McCroskery S, McLellan J, Mena I, Meseck M, Phonrat B, Sabmee Y, Singchareon R, Slamanig S, Suthepakul N, Tcheou J, Thantamnu N, Theerasurakarn S, Tran S, Vilasmongkolchai T, White JA, Garcia-Sastre A, Palese P, Krammer F, Poopipatpol K, Wirachwong P, Hjorth R, Innis BL. Safety and Immunogenicity of an Inactivated Recombinant Newcastle Disease Virus Vaccine Expressing SARS-CoV-2 Spike: Interim Results of a Randomised, Placebo-Controlled, Phase 1/2 Trial. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2021. [PMID: 34580673 DOI: 10.1101/2021.09.17.21263758] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Background Production of affordable coronavirus disease 2019 (COVID-19) vaccines in low- and middle-income countries is needed. NDV-HXP-S is an inactivated egg-based Newcastle disease virus vaccine expressing the spike protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). It's being developed in Thailand, Vietnam, and Brazil; herein are initial results from Thailand. Methods This phase 1 stage of a randomised, dose-escalation, observer-blind, placebo-controlled, phase 1/2 trial was conducted at the Vaccine Trial Centre, Mahidol University (Bangkok). Healthy adults aged 18-59 years, non-pregnant and negative for SARS-CoV-2 antibodies were eligible. Participants were block randomised to receive one of six treatments by intramuscular injection twice, 28 days apart: 1 µg±CpG1018 (a toll-like receptor 9 agonist), 3 µg±CpG1018, 10 µg, or placebo. Participants and personnel assessing outcomes were masked to treatment. The primary outcomes were solicited and spontaneously reported adverse events (AEs) during 7 and 28 days after each vaccination, respectively. Secondary outcomes were immunogenicity measures (anti-S IgG and pseudotyped virus neutralisation). An interim analysis assessed safety at day 57 in treatment-exposed individuals and immunogenicity through day 43 per protocol. ClinicalTrials.gov ( NCT04764422 ). Findings Between March 20 and April 23, 2021, 377 individuals were screened and 210 were enrolled (35 per group); all received dose one; five missed dose two. The most common solicited AEs among vaccinees, all predominantly mild, were injection site pain (<63%), fatigue (<35%), headache (<32%), and myalgia (<32%). The proportion reporting a vaccine-related AE ranged from 5·7% to 17·1% among vaccine groups and was 2·9% in controls; there was no vaccine-related serious adverse event. The 10 µg formulation's immunogenicity ranked best, followed by 3 µg+CpG1018, 3 µg, 1 µg+CpG1018, and 1 µg formulations. On day 43, the geometric mean concentrations of 50% neutralising antibody ranged from 122·23 IU/mL (1 µg, 95% CI 86·40-172·91) to 474·35 IU/mL (10 µg, 95% CI 320·90-701·19), with 93·9% to 100% of vaccine groups attaining a ≥4-fold increase over baseline. Interpretation NDV-HXP-S had an acceptable safety profile and potent immunogenicity. The 3 µg and 3 µg+CpG1018 formulations advanced to phase 2. Funding National Vaccine Institute (Thailand), National Research Council (Thailand), Bill & Melinda Gates Foundation, National Institutes of Health (USA).
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White JA, Lal M. Technical product attributes in development of an oral enteric vaccine for infants. Vaccine 2020; 37:4800-4804. [PMID: 31358239 DOI: 10.1016/j.vaccine.2019.02.060] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 02/12/2019] [Accepted: 02/25/2019] [Indexed: 11/17/2022]
Abstract
Development of an oral enteric vaccine for infants is important for Shigella and enterotoxigenic Escherichia coli (ETEC) vaccine development. At a recent workshop titled "Technical Product Attributes in Development of an Oral Enteric Vaccine for Infants," at the 2nd International Vaccines Against Shigella and ETEC Conference (VASE Conference), the preferred product attributes for development were discussed for these vaccines. The aims of this workshop were to identify gaps and gather opinions from key experts from preclinical, process development, manufacturing, regulatory, and clinical areas to fine-tune and refine key target product attributes for infant oral vaccine development. The workshop used some examples of marketed oral infant vaccines to discuss potential improvements that can be made, such as inclusion of preservatives, multidose vials, and antacid buffer presentation (liquid or lyophilized) in novel oral enteric vaccine development.
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Lal M. Freeze-dried tablets for oral vaccine delivery: Ease of administration and potential for production in existing facilities. Vaccine 2020; 38:4142-4145. [PMID: 32321686 DOI: 10.1016/j.vaccine.2020.04.018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 03/17/2020] [Accepted: 04/07/2020] [Indexed: 10/24/2022]
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McAdams DH, Lal M, Lai M, Quintanar-Solares M. Feasibility Study for the Rectal Route of Administration for Gentamicin Evaluated in the Neonatal Minipig Model. J Pharm Sci 2019; 109:992-1001. [PMID: 31404543 DOI: 10.1016/j.xphs.2019.08.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 07/26/2019] [Accepted: 08/06/2019] [Indexed: 12/18/2022]
Abstract
Neonatal infections are a major cause of newborn mortality in low- and middle-income countries, particularly in areas without access to inpatient care. To address this, the World Health Organization developed guidelines for delivering simplified antibiotic regimens (oral amoxicillin and intramuscular gentamicin) in outpatient settings to young infants with suspected serious bacterial infection when referral is not feasible. However, there are still limitations to access, as the regimen requires a health care provider trained in giving intramuscular injections to infants. To provide a needle-free, simplified alternate to intramuscular delivery, PATH investigated the feasibility of the rectal administration of gentamicin. Potential formulations were screened by in vitro testing, and 2 liquid enema formulations and a cocoa butter suppository were developed and evaluated in a preclinical study of the rectal uptake of gentamicin in a neonatal minipig model. Sera samples from the control group, dosed by intramuscular injection, resulted in expected sera concentrations of gentamicin, but no gentamicin was detected in the sera of groups rectally dosed with the test formulations. The results of this study did not provide evidence to support the therapeutic feasibility of rectally absorbed gentamicin.
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Berrington JE, Clarke P, Embleton ND, Ewer AK, Geethanath R, Gupta S, Lal M, Oddie S, Shafiq A, Vasudevan C, Bührer C. Retinopathy of prematurity screening at ≥30 weeks: urinary NTpro-BNP performance. Acta Paediatr 2018; 107:1722-1725. [PMID: 29617052 DOI: 10.1111/apa.14354] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2018] [Revised: 03/27/2018] [Accepted: 03/28/2018] [Indexed: 11/29/2022]
Abstract
AIM Urinary N-terminal B-type natriuretic peptide NTproBNP levels are associated with the development of retinopathy of prematurity (ROP) in infants <30 weeks of gestation. The incidence of ROP in more mature infants who meet other ROP screening criteria is very low. We therefore aimed to test whether urinary NTproBNP predicted ROP development in these infants. METHODS Prospective observational study in 151 UK infants ≥30 + 0 weeks of gestation but also <32 weeks of gestation and/or <1501 g, to test the hypothesis that urinary NTproBNP levels on day of life (DOL) 14 and 28 were able to predict ROP development. RESULTS Urinary NTproBNP concentrations on day 14 and day 28 of life did not differ between infants with and without ROP (medians 144 vs 128 mcg/mL, respectively, p = 0.86 on DOL 14 and medians 117 vs 94 mcg/mL, respectively, p = 0.64 on DOL28). CONCLUSION The association previously shown for infants <30 completed weeks between urinary NTproBNP and the development of ROP was not seen in more mature infants. Urinary NTproBNP does not appear helpful in rationalising direct ophthalmoscopic screening for ROP in more mature infants, and may suggest a difference in pathophysiology of ROP in this population.
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Derby N, Lal M, Aravantinou M, Kizima L, Barnable P, Rodriguez A, Lai M, Wesenberg A, Ugaonkar S, Levendosky K, Mizenina O, Kleinbeck K, Lifson JD, Peet MM, Lloyd Z, Benson M, Heneine W, O'Keefe BR, Robbiani M, Martinelli E, Grasperge B, Blanchard J, Gettie A, Teleshova N, Fernández-Romero JA, Zydowsky TM. Griffithsin carrageenan fast dissolving inserts prevent SHIV HSV-2 and HPV infections in vivo. Nat Commun 2018; 9:3881. [PMID: 30250170 PMCID: PMC6155161 DOI: 10.1038/s41467-018-06349-0] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Accepted: 08/24/2018] [Indexed: 01/04/2023] Open
Abstract
Human immunodeficiency virus (HIV) pre-exposure prophylaxis (PrEP) strategies with proven in vivo efficacy rely on antiretroviral drugs, creating the potential for drug resistance and complicated treatment options in individuals who become infected. Moreover, on-demand products are currently missing from the PrEP development portfolio. Griffithsin (GRFT) is a non-antiretroviral HIV entry inhibitor derived from red algae with an excellent safety profile and potent activity in vitro. When combined with carrageenan (CG), GRFT has strong activity against herpes simplex virus-2 (HSV-2) and human papillomavirus (HPV) in vitro and in vivo. Here, we report that GRFT/CG in a freeze-dried fast dissolving insert (FDI) formulation for on-demand use protects rhesus macaques from a high dose vaginal SHIV SF162P3 challenge 4 h after FDI insertion. Furthermore, the GRFT/CG FDI also protects mice vaginally against HSV-2 and HPV pseudovirus. As a safe, potent, broad-spectrum, on-demand non-antiretroviral product, the GRFT/CG FDI warrants clinical development.
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Lal M, Lai M, Ugaonkar S, Wesenberg A, Kizima L, Rodriguez A, Levendosky K, Mizenina O, Fernández-Romero J, Zydowsky T. Development of a Vaginal Fast-Dissolving Insert Combining Griffithsin and Carrageenan for Potential Use Against Sexually Transmitted Infections. J Pharm Sci 2018; 107:2601-2610. [PMID: 29902477 DOI: 10.1016/j.xphs.2018.06.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Revised: 04/24/2018] [Accepted: 06/05/2018] [Indexed: 10/14/2022]
Abstract
Precoital, on-demand topical microbicides to reduce a woman's risk of sexually transmitted infections have been in development for nearly 3 decades, but no product has been approved due to acceptability issues and poor adherence in clinical trials. We set out to develop a self-administered vaginal fast-dissolving insert (FDI) produced by freeze-drying that would deliver safe and effective amounts of the antiviral agents griffithsin (GRFT) and carrageenan (CG) and would have properties women and their partners find acceptable. We evaluated FDI physical criteria, attributes of the gel produced upon dissolving, and GRFT stability. The lead formulation, FDI-024, was selected from 13 candidates and contains 4 mg of GRFT, 15 mg of CG, and excipients (the cryoprotectant sucrose and bulking agents dextran 40 and mannitol). The FDI exhibits good friability and hardness and is stable for at least 6 months at up to 40°C/75% relative humidity. It disintegrates in less than 60 s in a physiologically relevant volume (∼1 mL) of simulated vaginal fluid, forming a viscous semi-solid gel with favorable mucoadhesive and spreading properties. The formulation retains the antiviral activity of GRFT and CG against HIV type 1 and human papillomavirus, respectively, in cell-based assays.
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Vellarikkal SK, Jayarajan R, Verma A, Ravi R, Senthilvel V, Kumar A, Saini L, Gulati S, Lal M, Mathur A, Chhetri MK, Faruq M, Scaria V, Sivasubbu S. A founder mutation MLC1 c.736delA associated with megalencephalic leukoencephalopathy with subcortical cysts-1 in north Indian kindred. Clin Genet 2018; 94:271-273. [PMID: 29667716 DOI: 10.1111/cge.13251] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Revised: 03/01/2018] [Accepted: 03/19/2018] [Indexed: 11/28/2022]
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Pittman DW, Brantly AM, Drobonick AL, King HT, Mesta DC, Richards CG, Lal M, Lai M. The Palatability of Lopinavir and Ritonavir Delivered by an Innovative Freeze-Dried Fast-Dissolving Tablet Formulation. AIDS Res Treat 2018; 2018:5908167. [PMID: 29593900 PMCID: PMC5822810 DOI: 10.1155/2018/5908167] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Accepted: 12/03/2017] [Indexed: 01/19/2023] Open
Abstract
Negative hedonic sensory qualities of HIV antiretroviral drugs often reduce patient adherence particularly in pediatric populations requiring oral consumption. This study examines the palatability of an innovative delivery mechanism utilizing a freeze-drying-in-blister approach to create fast-dissolving tablets (FDTs) containing a fixed-dose combination of lopinavir and ritonavir (LPV/r). Consumption patterns of solutions during brief-access and long-term testing and baby foodstuff consumption were analyzed to evaluate the orosensory detection and avoidance of placebo FDTs containing no LPV/r (FDT-) and FDTs containing LPV/r (FDT+). Rats showed no change in consumption patterns for the placebo FDT- compared with control solutions. Rats can detect but do not avoid FDT+ at body-weight-adjusted dosages in both brief-access (30-s) and long-term (23 h) consumption tests. There is an aversive response to concentrated doses of FDT+ during brief-access tests that cannot be masked by 25% sucrose. However, the strongest FDT+ concentration was not rejected when mixed with 50 g of applesauce, banana sauce, or rice cereal baby foodstuffs. The averseness of the FDT+ was associated with the presence of LPV/r and not the FDT- formulation itself. The novel FDT formulation appears to be a palatable delivery mechanism for oral antiretroviral pharmaceuticals especially when mixed with baby foodstuffs.
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White JA, Haghighi C, Brunner J, Estrada M, Lal M, Chen D. Preformulation studies with the Escherichia coli double mutant heat-labile toxin adjuvant for use in an oral vaccine. J Immunol Methods 2017; 451:83-89. [PMID: 28939395 PMCID: PMC5703769 DOI: 10.1016/j.jim.2017.09.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 09/12/2017] [Accepted: 09/12/2017] [Indexed: 11/25/2022]
Abstract
Double mutant heat-labile toxin (dmLT) is a promising adjuvant for oral vaccine administration. The aims of our study were to develop sensitive methods to detect low concentrations of dmLT and to use the assays in preformulation studies to determine whether dmLT remains stable under conditions encountered by an oral vaccine. We developed a sandwich ELISA specific for intact dmLT and a sensitive SDS-PAGE densitometry method, and tested stability of dmLT in glass and plastic containers, in saliva, at the pH of stomach fluid, and in high-osmolarity buffers. The developed ELISA has a quantification range of 62.5 to 0.9 ng/mL and lower limit of detection of 0.3 ng/mL; the limit of quantification of the SDS-PAGE is 10 μg/mL. This work demonstrates the application of dmLT assays in preformulation studies to development of an oral vaccine containing dmLT. Assays reported here will facilitate the understanding and use of dmLT as an adjuvant.
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Lal M, Lai M, Estrada M, Zhu C. Developing a Flexible Pediatric Dosage Form for Antiretroviral Therapy: A Fast-Dissolving Tablet. J Pharm Sci 2017; 106:2173-2177. [PMID: 28499879 PMCID: PMC5514784 DOI: 10.1016/j.xphs.2017.05.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Revised: 04/20/2017] [Accepted: 05/01/2017] [Indexed: 11/26/2022]
Abstract
Current presentations of the anti-HIV drugs lopinavir and ritonavir make appropriate dosing for children difficult. We conducted a feasibility study to develop a formulation for these drugs with child-safe excipients in a flexible dosage form for children across the pediatric age spectrum. The freeze-drying in blister approach was used to produce fast-dissolving tablets (FDTs), as these can be dispersed in fluids for easy administration, even to infants, and appropriate portions of the dispersion can be given for different ages/weights. We combined various ratios of polymers, surfactants, and bulking agents to incorporate the 2 highly hydrophobic drugs while maintaining drug stability, rapid disintegration, and good handling properties. The final FDT was robust and disintegrated in 0.5 mL of fluid in 10 s with up to 4 tablets dissolving in 2 mL to achieve varying doses accommodated in a common teaspoon. Drug recovery after dissolution in small volumes of liquid or fluid foods was 90%-105%. The final candidate FDT was stable at 40°C, 75% relative humidity for up to 3 months. FDTs are a promising flexible dosage form for antiretroviral treatment for pediatric patients, especially in low-resource settings.
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Iyengar PK, Srinivasan M, Sikka SK, Shyam A, Chitra V, Kulkarni LV, Rout RK, Krishnan MS, Malhotra SK, Gaonkar DG, Sadhukhan HK, Nagvenkar VB, Nayar MG, Mitra SK, Raghunathan P, Degwekar SB, Radhakrishnan TP, Sundaresan R, Arunachalam J, Raju VS, Kalyanaraman R, Gangadharan S, Venkateswaran G, Moorthy PN, Venkateswarlu KS, Yuvaraju B, Kishore K, Guha SN, Panajkar MS, Rao KA, Raj P, Suryanarayana P, Sathyamoorthy A, Datta T, Bose H, Prabhu LH, Sankaranarayanan S, Shetiya RS, Veeraraghavan N, Murthy TS, Sen BK, Joshi PV, Sharma KGB, Joseph TB, Iyengar TS, Shrikhande VK, Mittal KC, Misra SC, Lal M, Rao PS. Bhabha Atomic Research Centre Studies in Cold Fusion. ACTA ACUST UNITED AC 2017. [DOI: 10.13182/fst90-a29233] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Thakur A, Lal M. Cemented Hemiarthroplasty in Elderly Osteoporotic Unstable Trochanteric Fractures using Fracture Window. Malays Orthop J 2017; 10:5-10. [PMID: 28435540 PMCID: PMC5333696 DOI: 10.5704/moj.1603.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Introduction: We would like to analyze the role of cemented hemiarthroplasty in elderly osteoporotic unstable intertrochanteric fractures through trochanteric fracture window. Materials and Methods: The study was conducted from July 2011 to July 2014. From a total of 265 consecutive patients with intertrochanteric fractures of 42 patients were selected according to inclusion criteria and results were analyzed prospectively. All patients were operated at tertiary care institute. Patients which matched the inclusion criteria were selected. 42 patients entered the study and all completed the study. Primary cemented hemiarthroplasty was done in all patients. Modified Harris Hip Score was used to assess all the patients. Results: 42 patients were included in the study with an average age of 80.7 years. Only AO/OTA type 31-A2.2 and 31-A2.3 were included, average HHS at final follow up of three years was 86.2. No revision or reoperation was done. Conclusion: In a selected cohort of patients primary prosthetic replacement in elderly osteoporotic unstable intertrochanteric fractures is good option and the surgical technique allowed us to perform it more easily.
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Lal M, Jarrahian C. Presentation matters: Buffers, packaging, and delivery devices for new, oral enteric vaccines for infants. Hum Vaccin Immunother 2017; 13:46-49. [PMID: 27819524 PMCID: PMC5287318 DOI: 10.1080/21645515.2016.1238536] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Accepted: 09/14/2016] [Indexed: 11/01/2022] Open
Abstract
Oral administration of vaccines is simpler and more acceptable than injection via needle and syringe, particularly for infants (Fig. 1) This route is promising for new vaccines in development against enterotoxigenic Escherichia coli (ETEC) and Shigella that cause childhood diarrhea with devastating consequences in low-resource countries. However, vaccine antigens and adjuvants given orally need buffering against the degradative effects of low stomach pH, and the type and volume of antacid buffer require special attention for infants. In addition, container/closure systems must be compatible with vaccine formulations, protect against water and gas transfer, and have minimal impact on the cold chain. Health care workers in demanding low-resource settings need an administration device that is easy to use, yet will accurately measure and safely deliver the correct vaccine dose. Developers must consider manufacturing capabilities, and immunization program managers want affordable vaccines. As new combination enteric vaccine candidates advance into clinical evaluation, features of the final vaccine presentation-liquid or dry format, diluent, buffer, primary and secondary packaging, and administration device-should be taken into account early in product development to achieve the greatest possible impact for the vaccine.
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Lal M, White J, Zhu C. Preparing an Adjuvanted Thermoresponsive Gel Formulation for Sublingual Vaccination. Methods Mol Biol 2017; 1494:153-163. [PMID: 27718192 DOI: 10.1007/978-1-4939-6445-1_11] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Thermoresponsive gels have unique physicochemical properties that may enable more effective mucosal delivery of active compounds. The thermoresponsive gel (TRG) formulation developed by our group for sublingual delivery maintains fluid-like liquid properties at 2 °C-8 °C and forms a gel at the physiological temperature (~37 °C) within a few seconds. Here, we describe the preparation of a thermoresponsive gel vaccine formulation. Our preclinical studies with various antigens suggest that the mucoadhesive, adjuvanted TRG formulation enabled increased contact of the vaccine antigen with the mucosa, resulting in increased mucosal response(s) with a potential for antigen dose reduction.
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Lal M, Jarrahian C, Zhu C, Hosken NA, McClurkan CL, Koelle DM, Saxon E, Roehrig A, Zehrung D, Chen D. Stability of live attenuated rotavirus vaccine with selected preservatives and primary containers. Vaccine 2016; 34:2483-9. [PMID: 27085171 DOI: 10.1016/j.vaccine.2016.03.093] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Revised: 03/22/2016] [Accepted: 03/29/2016] [Indexed: 10/22/2022]
Abstract
Rotavirus infection, which can be prevented by vaccination, is responsible for a high burden of acute gastroenteritis disease in children, especially in low-income countries. An appropriate formulation, packaging, and delivery device for oral rotavirus vaccine has the potential to reduce the manufacturing cost of the vaccine and the logistical impact associated with introduction of a new vaccine, simplify the vaccination procedure, and ensure that the vaccine is safely and accurately delivered to children. Single-dose prefilled presentations can be easy to use; however, they are typically more expensive, can be a bottleneck during production, and occupy a greater volume per dose vis-à-vis supply chain storage and medical waste disposal, which is a challenge in low-resource settings. Multi-dose presentations used thus far have other issues, including increased wastage of vaccine and the need for separate delivery devices. In this study, the goals were to evaluate both the technical feasibility of using preservatives to develop a liquid multi-dose formulation and the primary packaging alternatives for orally delivered, liquid rotavirus vaccines. The feasibility evaluation included evaluation of commonly used preservatives for compatibility with rotavirus vaccines and stability testing of rotavirus vaccine in various primary containers, including Lameplast's plastic tubes, BD's oral dispenser version of Uniject™ (Uniject DP), rommelag's blow-fill-seal containers, and MEDInstill's multi-dose vial and pouch. These presentations were compared to a standard glass vial. The results showed that none of the preservatives tested were compatible with a live attenuated rotavirus vaccine because they had a detrimental effect on the viability of the virus. In the presence of preservatives, vaccine virus titers declined to undetectable levels within 1 month. The vaccine formulation without preservatives maintained a stability profile over 12 months in all primary containers that was similar to its profile in standard glass vials. This study demonstrates that there are multiple options for the primary container for rotavirus vaccines intended for oral delivery. Selection of an optimal primary container should take into consideration additional factors, including stability as well as cold chain volume, usability, cost, and manufacturing feasibility.
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Bhau BS, Borah B, Ahmed R, Phukon P, Gogoi B, Sarmah DK, Lal M, Wann SB. Influence of root-knot nematode infestation on antioxidant enzymes, chlorophyll content and growth in Pogostemon cablin (Blanco) Benth. INDIAN JOURNAL OF EXPERIMENTAL BIOLOGY 2016; 54:254-261. [PMID: 27295922] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Plants adapt themselves to overcome adverse environmental conditions, and this involves a plethora of concurrent cellular activities. Physiological experiments or metabolic profiling can quantify this response. Among several diseases of Pogostemon cablin (Blanco) Benth. (Patchouli), root-knot nematode infection caused by Meloidogyne incognita (Kofoid and White) Chitwood causes severe damage to the plant and hence, the oil production. In the present study, we identified M. incognita morphologically and at molecular level using sequenced characterized amplified region marker (SCAR). M. incognita was artificially inoculated at different levels of second stage juveniles (J₂) to examine the effect on Patchouli plant growth parameters. Peroxidase and polyphenol oxidase enzyme activity and changes in the total phenol and chlorophyll contents in M. incognita was also evaluated in response to infection. The results have demonstrated that nematode infestation leads to increased peroxidase activities in the leaves of the patchouli plants and thereby, increase in phenolic content as a means of defence against nematode infestation. Chlorophyll content was also found decreased but no changes in polyphenol oxidase enzyme activity.
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Chandrasekaran L, Lal M, Van De Verg LL, Venkatesan MM. A study of different buffers to maximize viability of an oral Shigella vaccine. Vaccine 2015; 33:6156-60. [PMID: 26428454 DOI: 10.1016/j.vaccine.2015.09.063] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Revised: 08/13/2015] [Accepted: 09/19/2015] [Indexed: 11/15/2022]
Abstract
Live, whole cell killed and subunit vaccines are being developed for diarrheal diseases caused by V. cholerae, Shigella species, ETEC, and Campylobacter. Some of these vaccines can be administered orally since this route best mimics natural infection. Live vaccines administered orally have to be protected from the harsh acidic gastric environment. Milk and bicarbonate solutions have been administered to neutralize the stomach acid. For many Shigella vaccine trials, 100-120 ml of a bicarbonate solution is ingested followed by the live vaccine candidate, which is delivered in 30 ml of bicarbonate, water or saline. It is not clear if maximum bacterial viability is achieved under these conditions. Also, volumes of neutralizing buffer that are optimal for adults may be unsuitable for children and infants. To address these questions, we performed studies to determine the viability and stability of a Shigella sonnei vaccine candidate, WRSS1, in a mixture of different volumes of five different buffer solutions added to hydrochloric acid to simulate gastric acidity. Among the buffers tested, bicarbonate solution, rotavirus buffer and CeraVacx were better at neutralizing acid and maintaining the viability of WRSS1. Also, a much smaller volume of the neutralizing buffer was sufficient to counteract stomach acid while maintaining bacterial viability.
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Bhushan R, Lal M. Enantioseparation of amino alcohols by reversed-phase high-performance liquid chromatography using cyanuric chloride-based chiral derivatizing reagents having amino acids and their amides as chiral auxiliaries. ACTA CHROMATOGR 2014. [DOI: 10.1556/achrom.26.2014.3.2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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