The effect of plant tissue and vaccine formulation on the oral immunogenicity of a model plant-made antigen in sheep
- Pelosi, Assunta, Piedrafita, David, De Guzman, Giorgio, Shepherd, Robert, Hamill, John, Meeusen, Els, Walmsley, Amanda
- Authors: Pelosi, Assunta , Piedrafita, David , De Guzman, Giorgio , Shepherd, Robert , Hamill, John , Meeusen, Els , Walmsley, Amanda
- Date: 2012
- Type: Text , Journal article
- Relation: PLoS ONE Vol. 7, no. 12 (2012), p. 1-9
- Full Text:
- Reviewed:
- Description: Antigen-specific antibody responses against a model antigen (the B subunit of the heat labile toxin of enterotoxigenic Escherichia coli, LTB) were studied in sheep following oral immunisation with plant-made and delivered vaccines. Delivery from a root-based vehicle resulted in antigen-specific immune responses in mucosal secretions of the abomasum and small intestine and mesenteric lymph nodes. Immune responses from the corresponding leaf-based vaccine were more robust and included stimulation of antigen-specific antibodies in mucosal secretions of the abomasum. These findings suggest that oral delivery of a plant bioencapsulated antigen can survive passage through the rumen to elicit mucosal and systemic immune responses in sheep. Moreover, the plant tissue used as the vaccine delivery vehicle affects the magnitude of these responses. Funding: Dow AgroSciences, LLC; http://www.dowagro.com/; Australian Research Council; Linkage Grant Scheme; Grant Number LP088231; http://www.arc.gov. au. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscrip
- Authors: Pelosi, Assunta , Piedrafita, David , De Guzman, Giorgio , Shepherd, Robert , Hamill, John , Meeusen, Els , Walmsley, Amanda
- Date: 2012
- Type: Text , Journal article
- Relation: PLoS ONE Vol. 7, no. 12 (2012), p. 1-9
- Full Text:
- Reviewed:
- Description: Antigen-specific antibody responses against a model antigen (the B subunit of the heat labile toxin of enterotoxigenic Escherichia coli, LTB) were studied in sheep following oral immunisation with plant-made and delivered vaccines. Delivery from a root-based vehicle resulted in antigen-specific immune responses in mucosal secretions of the abomasum and small intestine and mesenteric lymph nodes. Immune responses from the corresponding leaf-based vaccine were more robust and included stimulation of antigen-specific antibodies in mucosal secretions of the abomasum. These findings suggest that oral delivery of a plant bioencapsulated antigen can survive passage through the rumen to elicit mucosal and systemic immune responses in sheep. Moreover, the plant tissue used as the vaccine delivery vehicle affects the magnitude of these responses. Funding: Dow AgroSciences, LLC; http://www.dowagro.com/; Australian Research Council; Linkage Grant Scheme; Grant Number LP088231; http://www.arc.gov. au. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscrip
Liver fluke vaccines in ruminants : Strategies, progress and future opportunities
- Toet, Hayley, Piedrafita, David, Spithill, Terry
- Authors: Toet, Hayley , Piedrafita, David , Spithill, Terry
- Date: 2014
- Type: Text , Journal article , Review
- Relation: International Journal for Parasitology Vol. 44, no. 12 (2014), p. 915-927
- Full Text: false
- Reviewed:
- Description: The development of a vaccine for Fasciola spp. in livestock is a challenge and would be advanced by harnessing our knowledge of acquired immune mechanisms expressed by resistant livestock against fluke infection. Antibody-dependent cell-mediated cytotoxicity directed to the surface tegument of juvenile/immature flukes is a host immune effector mechanism, suggesting that antigens on the surface of young flukes may represent prime candidates for a fluke vaccine. A Type 1 immune response shortly after fluke infection is associated with resistance to infection in resistant sheep, indicating that vaccine formulations should attempt to induce Type 1 responses to enhance vaccine efficacy. In cattle or sheep, an optimal fluke vaccine would need to reduce mean fluke burdens in a herd below the threshold of 30-54 flukes to ensure sustainable production benefits. Fluke infection intensity data suggest that vaccine efficacy of approximately 80% is required to reduce fluke burdens below this threshold in most countries. With the increased global prevalence of triclabendazole-resistant Fasciola hepatica, it may be commercially feasible in the short term to introduce a fluke vaccine of reasonable efficacy that will provide economic benefits for producers in regions where chemical control of new drug-resistant fluke infections is not viable. Commercial partnerships will be needed to fast-track new candidate vaccines using acceptable adjuvants in relevant production animals, obviating the need to evaluate vaccine antigens in rodent models. © 2014 Australian Society for Parasitology Inc.
Specific humoral response of hosts with variable schistosomiasis susceptibility
- Driguez, Patrick, McWilliam, Hamish, Gaze, Soraya, Piedrafita, David, Pearson, Mark, Nakajima, Rie, Duke, Mary, Trieu, Angela, Doolan, Denise, Cardoso, Fernanda, Jasinskas, Algis, Gobert, Geoffrey, Felgner, Philip, Loukas, Alex, Meeusen, Els, McManus, Donald
- Authors: Driguez, Patrick , McWilliam, Hamish , Gaze, Soraya , Piedrafita, David , Pearson, Mark , Nakajima, Rie , Duke, Mary , Trieu, Angela , Doolan, Denise , Cardoso, Fernanda , Jasinskas, Algis , Gobert, Geoffrey , Felgner, Philip , Loukas, Alex , Meeusen, Els , McManus, Donald
- Date: 2016
- Type: Text , Journal article
- Relation: Immunology and Cell Biology Vol. 94, no. 1 (2016), p. 52-65
- Full Text:
- Reviewed:
- Description: The schistosome blood flukes are some of the largest global causes of parasitic morbidity. Further study of the specific antibody response during schistosomiasis may yield the vaccines and diagnostics needed to combat this disease. Therefore, for the purposes of antigen discovery, sera and antibody-secreting cell (ASC) probes from semi-permissive rats and sera from susceptible mice were used to screen a schistosome protein microarray. Following Schistosoma japonicum infection, rats had reduced pathology, increased antibody responses and broader antigen recognition profiles compared with mice. With successive infections, rat global serological reactivity and the number of recognized antigens increased. The local antibody response in rat skin and lung, measured with ASC probes, increased after parasite migration and contributed antigen-specific antibodies to the multivalent serological response. In addition, the temporal variation of anti-parasite serum antibodies after infection and reinfection followed patterns that appear related to the antigen driving the response. Among the 29 antigens differentially recognized by the infected hosts were numerous known vaccine candidates, drug targets and several S. japonicum homologs of human schistosomiasis resistance markers - the tegument allergen-like proteins. From this set, we prioritized eight proteins that may prove to be novel schistosome vaccine and diagnostic antigens. © 2016 Australasian Society for Immunology Inc. All rights reserved.
- Authors: Driguez, Patrick , McWilliam, Hamish , Gaze, Soraya , Piedrafita, David , Pearson, Mark , Nakajima, Rie , Duke, Mary , Trieu, Angela , Doolan, Denise , Cardoso, Fernanda , Jasinskas, Algis , Gobert, Geoffrey , Felgner, Philip , Loukas, Alex , Meeusen, Els , McManus, Donald
- Date: 2016
- Type: Text , Journal article
- Relation: Immunology and Cell Biology Vol. 94, no. 1 (2016), p. 52-65
- Full Text:
- Reviewed:
- Description: The schistosome blood flukes are some of the largest global causes of parasitic morbidity. Further study of the specific antibody response during schistosomiasis may yield the vaccines and diagnostics needed to combat this disease. Therefore, for the purposes of antigen discovery, sera and antibody-secreting cell (ASC) probes from semi-permissive rats and sera from susceptible mice were used to screen a schistosome protein microarray. Following Schistosoma japonicum infection, rats had reduced pathology, increased antibody responses and broader antigen recognition profiles compared with mice. With successive infections, rat global serological reactivity and the number of recognized antigens increased. The local antibody response in rat skin and lung, measured with ASC probes, increased after parasite migration and contributed antigen-specific antibodies to the multivalent serological response. In addition, the temporal variation of anti-parasite serum antibodies after infection and reinfection followed patterns that appear related to the antigen driving the response. Among the 29 antigens differentially recognized by the infected hosts were numerous known vaccine candidates, drug targets and several S. japonicum homologs of human schistosomiasis resistance markers - the tegument allergen-like proteins. From this set, we prioritized eight proteins that may prove to be novel schistosome vaccine and diagnostic antigens. © 2016 Australasian Society for Immunology Inc. All rights reserved.
Rationale and methods of a randomized controlled trial of immunogenicity, safety and impact on carriage of pneumococcal conjugate and polysaccharide vaccines in infants in Papua New Guinea
- Lehmann, Deborah, Kirarock, Wendy, van den Biggelaar, Anita, Passey, Megan, Jacoby, Peter, Saleu, Gerard, Masiria, Geraldine, Nivio, Birunu, Greenhill, Andrew, Orami, Tilda, Francis, Jacinta, Ford, Rebecca, Kirkham, Lea-Ann, Solomon, Vela, Richmond, Peter, Pomat, William
- Authors: Lehmann, Deborah , Kirarock, Wendy , van den Biggelaar, Anita , Passey, Megan , Jacoby, Peter , Saleu, Gerard , Masiria, Geraldine , Nivio, Birunu , Greenhill, Andrew , Orami, Tilda , Francis, Jacinta , Ford, Rebecca , Kirkham, Lea-Ann , Solomon, Vela , Richmond, Peter , Pomat, William
- Date: 2017
- Type: Text , Journal article
- Relation: Pneumonia Vol. 9, no. 20 (2017), p.
- Full Text:
- Reviewed:
- Description: Background: Children in third-world settings including Papua New Guinea (PNG) experience early onset of carriage with a broad range of pneumococcal serotypes, resulting in a high incidence of severe pneumococcal disease and deaths in the first 2 years of life. Vaccination trials in high endemicity settings are needed to provide evidence and guidance on optimal strategies to protect children in these settings against pneumococcal infections. Methods: This report describes the rationale, objectives, methods, study population, follow-up and specimen collection for a vaccination trial conducted in an endemic and logistically challenging setting in PNG. The trial aimed to determine whether currently available pneumococcal conjugate vaccines (PCV) are suitable for use under PNG’s accelerated immunization schedule, and that a schedule including pneumococcal polysaccharide vaccine (PPV) in later infancy is safe and immunogenic in this high-risk population. Results: This open randomized-controlled trial was conducted between November 2011 and March 2016, enrolling 262 children aged 1 month between November 2011 and April 2014. The participants were randomly allocated (1:1) to receive 10-valent PCV (10vPCV) or 13-valent PCV (13vPCV) in a 1-2-3-month schedule, with further randomization to receive PPV or no PPV at age 9 months, followed by a 1/5th PPV challenge at age 23 months. A total of 1229 blood samples were collected to measure humoral and cellular immune responses and 1238 nasopharyngeal swabs to assess upper respiratory tract colonization and carriage load. Serious adverse events were monitored throughout the study. Of the 262 children enrolled, 87% received 3 doses of PCV, 79% were randomized to receive PPV or no PPV at age 9 months, and 67% completed the study at 24 months of age with appropriate immunization and challenge. Conclusion: Laboratory testing of the many samples collected during this trial will determine the impact of the different vaccine schedules and formulations on nasopharyngeal carriage, antibody production and function, and immune memory. The final data will inform policy on pneumococcal vaccine schedules in countries with children at high risk of pneumococcal disease by providing direct comparison of an accelerated schedule of 10vPCV and 13vPCV and the potential advantages of PPV following PCV immunization
- Authors: Lehmann, Deborah , Kirarock, Wendy , van den Biggelaar, Anita , Passey, Megan , Jacoby, Peter , Saleu, Gerard , Masiria, Geraldine , Nivio, Birunu , Greenhill, Andrew , Orami, Tilda , Francis, Jacinta , Ford, Rebecca , Kirkham, Lea-Ann , Solomon, Vela , Richmond, Peter , Pomat, William
- Date: 2017
- Type: Text , Journal article
- Relation: Pneumonia Vol. 9, no. 20 (2017), p.
- Full Text:
- Reviewed:
- Description: Background: Children in third-world settings including Papua New Guinea (PNG) experience early onset of carriage with a broad range of pneumococcal serotypes, resulting in a high incidence of severe pneumococcal disease and deaths in the first 2 years of life. Vaccination trials in high endemicity settings are needed to provide evidence and guidance on optimal strategies to protect children in these settings against pneumococcal infections. Methods: This report describes the rationale, objectives, methods, study population, follow-up and specimen collection for a vaccination trial conducted in an endemic and logistically challenging setting in PNG. The trial aimed to determine whether currently available pneumococcal conjugate vaccines (PCV) are suitable for use under PNG’s accelerated immunization schedule, and that a schedule including pneumococcal polysaccharide vaccine (PPV) in later infancy is safe and immunogenic in this high-risk population. Results: This open randomized-controlled trial was conducted between November 2011 and March 2016, enrolling 262 children aged 1 month between November 2011 and April 2014. The participants were randomly allocated (1:1) to receive 10-valent PCV (10vPCV) or 13-valent PCV (13vPCV) in a 1-2-3-month schedule, with further randomization to receive PPV or no PPV at age 9 months, followed by a 1/5th PPV challenge at age 23 months. A total of 1229 blood samples were collected to measure humoral and cellular immune responses and 1238 nasopharyngeal swabs to assess upper respiratory tract colonization and carriage load. Serious adverse events were monitored throughout the study. Of the 262 children enrolled, 87% received 3 doses of PCV, 79% were randomized to receive PPV or no PPV at age 9 months, and 67% completed the study at 24 months of age with appropriate immunization and challenge. Conclusion: Laboratory testing of the many samples collected during this trial will determine the impact of the different vaccine schedules and formulations on nasopharyngeal carriage, antibody production and function, and immune memory. The final data will inform policy on pneumococcal vaccine schedules in countries with children at high risk of pneumococcal disease by providing direct comparison of an accelerated schedule of 10vPCV and 13vPCV and the potential advantages of PPV following PCV immunization
Prospects for immunoprophylaxis against fasciola hepatica (Liver Fluke)
- Spithill, Terry, Carmona, Carlos, Piedrafita, David, Smooker, Peter
- Authors: Spithill, Terry , Carmona, Carlos , Piedrafita, David , Smooker, Peter
- Date: 2012
- Type: Text , Book chapter
- Relation: Parasitic Helminths: Targets, Screens, Drugs and Vaccines (Drug Discovery in Infectious Diseases series) Chapter 28 p. 465-484
- Full Text: false
- Reviewed:
- Description: Despite considerable research focused on the development of vaccines for Fasciola (liver fluke) infections in ruminants, there is still no commercial vaccine. Development of vaccines has been hindered both by our lack of insight into natural acquired immune mechanisms expressed by ruminants against fluke infection as well as a lack of immune correlates on hosts that are protected by experimental vaccines. In this chapter, we review the prospects and challenges we face regarding the development of experimental fluke vaccines, the nature of immune responses associated with host resistance, the potential for combination vaccines, and the criteria for commercial interest in a vaccine, including the minimal efficacy necessary to produce economic benefits in ruminants. Due to the widespread resistance of Fasciola to triclabendazole, we also discuss the potential demand for a human vaccine. © 2012 Wiley-VCH Verlag GmbH & Co. KGaA.
SARS-CoV-2 does not replicate in embryonated hen's eggs or in MDCK cell lines
- Barr, Ian, Rynehart, Cleve, Whitney, Paul, Druce, Julian
- Authors: Barr, Ian , Rynehart, Cleve , Whitney, Paul , Druce, Julian
- Date: 2020
- Type: Text , Journal article
- Relation: Euro surveillance : bulletin Europeen sur les maladies transmissibles = European communicable disease bulletin Vol. 25, no. 25 (2020), p.
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- Description: The advent of COVID-19, has posed a risk that human respiratory samples containing human influenza viruses may also contain SARS-CoV-2. This potential risk may lead to SARS-CoV-2 contaminating conventional influenza vaccine production platforms as respiratory samples are used to directly inoculate embryonated hen's eggs and continuous cell lines that are used to isolate and produce influenza vaccines. We investigated the ability of these substrates to propagate SARS-CoV-2 and found that neither could support SARS-CoV-2 replication.
- Authors: Barr, Ian , Rynehart, Cleve , Whitney, Paul , Druce, Julian
- Date: 2020
- Type: Text , Journal article
- Relation: Euro surveillance : bulletin Europeen sur les maladies transmissibles = European communicable disease bulletin Vol. 25, no. 25 (2020), p.
- Full Text:
- Reviewed:
- Description: The advent of COVID-19, has posed a risk that human respiratory samples containing human influenza viruses may also contain SARS-CoV-2. This potential risk may lead to SARS-CoV-2 contaminating conventional influenza vaccine production platforms as respiratory samples are used to directly inoculate embryonated hen's eggs and continuous cell lines that are used to isolate and produce influenza vaccines. We investigated the ability of these substrates to propagate SARS-CoV-2 and found that neither could support SARS-CoV-2 replication.
COVID-19 in Africa : rethinking the tools to manage future pandemics
- Emahi, Ismaila, Watts, Mimmie, Azibere, Samuel, Morrison, Joseph, Sarpong, Kwabena
- Authors: Emahi, Ismaila , Watts, Mimmie , Azibere, Samuel , Morrison, Joseph , Sarpong, Kwabena
- Date: 2021
- Type: Text , Journal article
- Relation: African Health Sciences Vol. 21, no. 4 (2021), p. 1509-1517
- Full Text:
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- Description: Corona virus disease 2019 (COVID-19) remains an incurable, progressive pneumonia-like illness characterized by fever, dry cough, fatigue, and headache during its early stages. COVID-19 has ultimately resulted in mortality in at least 2 million people worldwide. Millions of people globally have already been affected by this disease, and the numbers are expected to increase, perhaps until an effective cure or vaccine is identified. Although Africa was initially purported by the World Health Organization (WHO) to be severely hit by the pandemic, Africa recorded the least number of cases during the first wave, with lowest rates of infections, compared to Asia, Europe, and the Americas. This statistic might be attributed to the low testing capacity, existing public health awareness and lessons learnt during Ebola epidemic. Nonetheless, the relatively low rate of infection should be an opportunity for Africa to be better prepared to overcome this and future epidemics. In this paper, the authors provide insights into the dynamics and transmission of the severe acute respiratory syndrome corona virus (SARS-CoV-2) during the first wave of the pandemic; possible explanations into the relatively low rates of infection recorded in Africa; with recommendations for Africa to continue to fight Covid-19; and position itself to effectively manage future pandemics. © 2021 Emahi I et al.
- Authors: Emahi, Ismaila , Watts, Mimmie , Azibere, Samuel , Morrison, Joseph , Sarpong, Kwabena
- Date: 2021
- Type: Text , Journal article
- Relation: African Health Sciences Vol. 21, no. 4 (2021), p. 1509-1517
- Full Text:
- Reviewed:
- Description: Corona virus disease 2019 (COVID-19) remains an incurable, progressive pneumonia-like illness characterized by fever, dry cough, fatigue, and headache during its early stages. COVID-19 has ultimately resulted in mortality in at least 2 million people worldwide. Millions of people globally have already been affected by this disease, and the numbers are expected to increase, perhaps until an effective cure or vaccine is identified. Although Africa was initially purported by the World Health Organization (WHO) to be severely hit by the pandemic, Africa recorded the least number of cases during the first wave, with lowest rates of infections, compared to Asia, Europe, and the Americas. This statistic might be attributed to the low testing capacity, existing public health awareness and lessons learnt during Ebola epidemic. Nonetheless, the relatively low rate of infection should be an opportunity for Africa to be better prepared to overcome this and future epidemics. In this paper, the authors provide insights into the dynamics and transmission of the severe acute respiratory syndrome corona virus (SARS-CoV-2) during the first wave of the pandemic; possible explanations into the relatively low rates of infection recorded in Africa; with recommendations for Africa to continue to fight Covid-19; and position itself to effectively manage future pandemics. © 2021 Emahi I et al.
The experiences of people with diabetes during covid-19 pandemic lockdown
- Al-Moteri, Modi, Plummer, Virginia, Youssef, Hanan, Yaseen, Ruba, Al Malki, Mohammed, Elryah, Ahmed, Al Karani, Ahmed
- Authors: Al-Moteri, Modi , Plummer, Virginia , Youssef, Hanan , Yaseen, Ruba , Al Malki, Mohammed , Elryah, Ahmed , Al Karani, Ahmed
- Date: 2022
- Type: Text , Journal article
- Relation: International Journal of Environmental Research and Public Health Vol. 19, no. 1 (2022), p.
- Full Text:
- Reviewed:
- Description: Little is known about the theoretical foundation underling the response of people with diabetes managing their everyday routines during COVID-19 pandemic lockdown. Aim: To explore the experience of people with diabetes during COVID-19 pandemic lockdown in light of the risk perception, response and behavioral change theories. Method: A qualitative descriptive design was employed, and Braun and Clark’s six step analysis were used for thematic analysis. Semi-structured interviews were conducted online using Zoom Videos Communication. Result: Five themes were defined as follows: (1) perceived the threat and faced their fears, (2) appraised the damage, (3) identified the challenges, (4) modified their routine, and (5) identified the strengths that facilitate the efficacy of their response. There were eight sub-themes within the themes. Conclusion: The results of this study may provide an opportunity for nurses to reflect on issues highlighted by the patients regarding more effective communication, knowledge and skill development for people to support self-care during national emergencies. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.
- Authors: Al-Moteri, Modi , Plummer, Virginia , Youssef, Hanan , Yaseen, Ruba , Al Malki, Mohammed , Elryah, Ahmed , Al Karani, Ahmed
- Date: 2022
- Type: Text , Journal article
- Relation: International Journal of Environmental Research and Public Health Vol. 19, no. 1 (2022), p.
- Full Text:
- Reviewed:
- Description: Little is known about the theoretical foundation underling the response of people with diabetes managing their everyday routines during COVID-19 pandemic lockdown. Aim: To explore the experience of people with diabetes during COVID-19 pandemic lockdown in light of the risk perception, response and behavioral change theories. Method: A qualitative descriptive design was employed, and Braun and Clark’s six step analysis were used for thematic analysis. Semi-structured interviews were conducted online using Zoom Videos Communication. Result: Five themes were defined as follows: (1) perceived the threat and faced their fears, (2) appraised the damage, (3) identified the challenges, (4) modified their routine, and (5) identified the strengths that facilitate the efficacy of their response. There were eight sub-themes within the themes. Conclusion: The results of this study may provide an opportunity for nurses to reflect on issues highlighted by the patients regarding more effective communication, knowledge and skill development for people to support self-care during national emergencies. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.
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