Displaying publications 1 - 20 of 138 in total

Abstract:
Sort:
  1. Barnard RT
    Expert Rev Vaccines, 2010 May;9(5):461-3.
    PMID: 20450319 DOI: 10.1586/erv.10.48
    The Recombinant Vaccines: Strategies for Candidate Discovery and Vaccine Delivery conference, organized by EuroSciCon, hosted a group of UK-based and international scientists from as far afield as Malaysia and Australia. Genomic analyses of pathogens and elucidation of mechanisms of pathogenesis has advanced candidate discovery and development of vaccines. Therefore, it was timely that this conference featured, in addition to detailed expositions of target selection and clinical trials, presentations on manufacturability, scale-up and delivery of vaccines. Ten talks were presented. This meeting report describes the key topics presented and the themes that emerged from this conference.
    Matched MeSH terms: Bacterial Vaccines/administration & dosage; Viral Vaccines/administration & dosage
  2. Hambali IU, Bhutto KR, Jesse FFA, Lawan A, Odhah MN, Wahid AH, et al.
    Microb Pathog, 2018 Nov;124:101-105.
    PMID: 30114463 DOI: 10.1016/j.micpath.2018.08.017
    Mastitis is an inflammatory condition of the udder that occurs as a result of the release of leucocytes into the udder in a response to bacterial invasion. The major causes of mastitis are an array of gram positive and negative bacteria, however, algae, virus, fungi, mechanical or thermal injury to the gland have also been identified as possible causes. Mastitis vaccines are yet to be developed using Malaysian local isolate of bacteria. The objective of the present experimental trial was to develop a monovalent vaccine against mastitis using S. aureus of Malaysian isolate and to evaluate the clinical responses such as temperature, respiratory rates and heart rates in vaccinated cows. S. aureus is a major causative bacteria in clinical and subclinical types of mastitis in cows. Four concentrations of the bacterin (106, 107, 108 and 109 cfu/ml of the local isolate of S. aureus) were prepared using Aluminium potassium sulfate adjuvant. Thirty cows were grouped into four treatment groups (B, C, D and E) with a fifth group as control (A). These groups were vaccinated intramuscularly(IM) with the prepared monovalent vaccine and its influence on the vital signs were intermittently measured. The mean of rectal temperature was significantly different (p˂ 0.05) at 0hr Post Vaccination [1]" in groups D and E (39.5 ± 0.15 °C and 39.4 ± 0.15 °C respectively) and at 3 h PV in groups C, D and E (39.8 ± 0.14 °C, 39.9 ± 0.14 °C and 40.3 ± 0.14 °C respectively) compared to the control group. This indicated a sharp increased rectal temperatures between 0hr and 3 h PV in groups C, D and E which later declined at 24 h PV. The mean of rectal temperature of group E was significantly different (p˂ 0.05) at weeks 1 and 2 PV (39.87 ± 0.19 °C and 39.80 ± 0.18 °C respectively) compared to the control group. The mean of heart rate was significantly different (p˂ 0.05) at week 1 PV in groups D and E (83.0 ± 3.8 beats/minute and 80.0 ± 3.8 °C respectively) compared to control. A trending decrease was however observed in heart rates of group E from weeks through 4 PV and in group D from weeks 1 through 3 PV. The mean of respiratory rates was significantly different (p˂ 0.05) at week 3 PV in group B and D (31.0 ± 1.2 breaths/minute and 28.0 ± 1.2 breaths/minute) compared to control. In conclusion, this study highlights responses of these vital signs due to vaccination against S. aureus causing mastitis in cows. To the best of our knowledge the findings of this study adds value to the shallow literature on vital signs alterations in cows vaccinated against mastitis as elevated levels of temperature and heart rates of group D and E indicated obvious response.
    Matched MeSH terms: Bacterial Vaccines/administration & dosage; Staphylococcal Vaccines/administration & dosage
  3. Capeding MR, Tran NH, Hadinegoro SR, Ismail HI, Chotpitayasunondh T, Chua MN, et al.
    Lancet, 2014 Oct 11;384(9951):1358-65.
    PMID: 25018116 DOI: 10.1016/S0140-6736(14)61060-6
    An estimated 100 million people have symptomatic dengue infection every year. This is the first report of a phase 3 vaccine efficacy trial of a candidate dengue vaccine. We aimed to assess the efficacy of the CYD dengue vaccine against symptomatic, virologically confirmed dengue in children.
    Matched MeSH terms: Dengue Vaccines/administration & dosage*
  4. Lam SK
    Expert Rev Vaccines, 2013 Sep;12(9):995-1010.
    PMID: 24053394 DOI: 10.1586/14760584.2013.824712
    Dengue is a major public health concern worldwide, with the number of infections increasing globally. The illness imposes the greatest economic and human burden on developing countries that have limited resources to deal with the scale of the problem. No cure for dengue exists; treatment is limited to rehydration therapy, and with vector control strategies proving to be relatively ineffective, a vaccine is an urgent priority. Despite the numerous challenges encountered in the development of a dengue vaccine, several vaccine candidates have shown promise in clinical development and it is believed that a vaccination program would be at least as cost-effective as current vector control programs. The lead candidate vaccine is a tetravalent, live attenuated, recombinant vaccine, which is currently in Phase III clinical trials. Vaccine introduction is a complex process that requires consideration and is discussed here. This review discusses the epidemiology, burden and pathogenesis of dengue, as well as the vaccine candidates currently in clinical development.
    Matched MeSH terms: Dengue Vaccines/administration & dosage*
  5. Noraini O, Sabri MY, Siti-Zahrah A
    J Aquat Anim Health, 2013 Jun;25(2):142-8.
    PMID: 23724958 DOI: 10.1080/08997659.2013.781553
    An initial evaluation of spray vaccination was carried out with 60 hybrid Red Tilapia Oreochromis spp., divided into three groups that consisted of 10 fish per group with duplicates. The formalin-killed cells (FKCs) of Streptococcus agalactiae were administered once to group 1 by spray and once daily for five consecutive days to group 2. Group 3 remained as the untreated control group and was sprayed with normal saline. A booster was given twice to all the groups, once at the second week and again at the fourth week after the first vaccination. After this initial evaluation, a challenge study was conducted with 40 tilapia divided into two groups that consisted of 10 fish per group with duplicates. Group 1 was vaccinated with FKCs of S. agalactiae by a single spray administration while group 2 remained as the untreated control group. A booster was given twice using the same protocol as in the initial evaluation. After 6 weeks, fish from one of the duplicate tanks from each of groups 1 and 2 were challenged with pathogenic S. agalactiae by intraperitoneal (IP) injection, while fish in another tank were challenged through immersion. Based on the observations, serum immunoglobulin M (IgM) levels were significantly higher (P < 0.05) in the challenged fish than in the either the preexposed fish or the control group 1 week after the initial exposure. However, no significant differences (P > 0.05) were noted between challenged groups 1 and 2. In addition, no significant differences (P > 0.05) were observed between the frequencies of exposure. The mucus IgM level, however, remained high after each booster until the end of the 8-week study period. Meanwhile, serum IgM levels decreased after the challenge. A higher percentage of survival was noted for fish challenged through immersion (80%) compared with IP injection (70%). These results suggested that single spray exposure was able to induce IgM, which gave moderate to high protection during the challenge study.
    Matched MeSH terms: Bacterial Vaccines/administration & dosage
  6. Lam SK, Burke D, Capeding MR, Chong CK, Coudeville L, Farrar J, et al.
    Vaccine, 2011 Nov 28;29(51):9417-22.
    PMID: 21864627 DOI: 10.1016/j.vaccine.2011.08.047
    Infection with dengue virus is a major public health problem in the Asia-Pacific region and throughout tropical and sub-tropical regions of the world. Vaccination represents a major opportunity to control dengue and several candidate vaccines are in development. Experts in dengue and in vaccine introduction gathered for a two day meeting during which they examined the challenges inherent to the introduction of a dengue vaccine into the national immunisation programmes of countries of the Asia-Pacific. The aim was to develop a series of recommendations to reduce the delay between vaccine licensure and vaccine introduction. Major recommendations arising from the meeting included: ascertaining and publicising the full burden and cost of dengue; changing the perception of dengue in non-endemic countries to help generate global support for dengue vaccination; ensuring high quality active surveillance systems and diagnostics; and identifying sustainable sources of funding, both to support vaccine introduction and to maintain the vaccination programme. The attendees at the meeting were in agreement that with the introduction of an effective vaccine, dengue is a disease that could be controlled, and that in order to ensure a vaccine is introduced as rapidly as possible, there is a need to start preparing now.
    Matched MeSH terms: Dengue Vaccines/administration & dosage*
  7. Künzi V, Klap JM, Seiberling MK, Herzog C, Hartmann K, Kürsteiner O, et al.
    Vaccine, 2009 Jun 2;27(27):3561-7.
    PMID: 19464535 DOI: 10.1016/j.vaccine.2009.03.062
    Despite the established benefit of intramuscular (i.m.) influenza vaccination, new adjuvants and delivery methods for comparable or improved immunogenicity are being explored. Intradermal (i.d.) antigen administration is hypothesized to initiate an efficient immune response at reduced antigen doses similar to that observed after i.m. full dose vaccination.
    Matched MeSH terms: Influenza Vaccines/administration & dosage
  8. Vaccine, 2006 Nov 10;24(44-46):6791-2.
    PMID: 17167887
    ESWI recommends that the 25 European Union nations strive to vaccinate one-third of their collective population every year by 2010. This translates into an annual vaccine usage of 150 million doses for a population of 455 million. However, the current vaccine usage in Europe is 79 million doses, meaning that only 40% of ESWI's recommended target population is being vaccinated in the EU-25. Indeed, the EU's current risk groups equal about 28% of its population, but it is estimated that less than 62% are being vaccinated with the current vaccine supply--the equivalent of 17% of the total population. Clearly, as ESWI noted in its concluding position paper at the Malta conference, "a large proportion of those traditionally assumed to be at most risk from influenza are not being vaccinated." How to change this and minimize the consequences of a pandemic? "It's very interesting how the arithmetic works, given the goal of immunizing 75 percent of Europe's high-risk group, " said Dr K.Nichol of the University of Minnesota Medical Center who chaired the session. "If you go from a trivalent vaccine to a monovalent one, then you triple the number of doses you can manufacture. Thus, you could produce enough doses for the entire population of the EU." However, there is no coordinated approach in Europe, meaning such an optimistic scenario is unlikely in the medium-term. For the time being, emphasis must be on raising public awareness and raising vaccination rates at the local level, starting with health care workers themselves. Here the role and attitude of health policy officials and--critically--health care workers are crucial. These front-line policy and healthcare professionals constitute both the problem and the solution to a more effective influenza vaccine effort in Europe: they know first-hand the institutional obstacles blocking progress--i.e., lack of resources, poorly focused public information campaigns, etc.--but their own work practices and attitudes can be misdirected, too. To identify the issues and help the participants produce a set of recommendations, ESWI brought in Penny Lawson from to facilitate Dr.K. Nichol to steer this session's workshop debate. The participants were a diverse group of 35 health care workers from Australia, Finland, France, Germany, Malaysia, Malta, Netherlands, Norway, Poland, Portugal, Spain, Sweden and the UK.
    Matched MeSH terms: Influenza Vaccines/administration & dosage*
  9. Chong WC, Basir R, Fei YM
    Asian Pac J Trop Med, 2013 Feb;6(2):85-94.
    PMID: 23339908 DOI: 10.1016/S1995-7645(13)60001-2
    Malaria is an intra-cellular parasitic protozoon responsible for millions of deaths annually. Host and parasite genetic factors are crucial in affecting susceptibility to malaria and progression of the disease. Recent increased deployment of vector controls and new artemisinin combination therapies have dramatically reduced the mortality and morbidity of malaria worldwide. However, the gradual emergence of parasite and mosquito resistance has raised alarm regarding the effectiveness of current artemisinin-based therapies. In this review, mechanisms of anti-malarial drug resistance in the Plasmodium parasite and new genetically engineered tools of research priorities are discussed. The complexity of the parasite lifecycle demands novel interventions to achieve global eradication. However, turning laboratory discovered transgenic interventions into functional products entails multiple experimental phases in addition to ethical and safety hurdles. Uncertainty over the regulatory status and public acceptance further discourage the implementation of genetically modified organisms.
    Matched MeSH terms: Malaria Vaccines/administration & dosage*
  10. Rehman IU, Khan TM
    Disaster Med Public Health Prep, 2016 08;10(4):539-40.
    PMID: 27263952 DOI: 10.1017/dmp.2016.91
    Matched MeSH terms: Poliovirus Vaccines/administration & dosage*
  11. Lolekha S, Cooksley G, Chan V, Isahak I, Ismael S, John J, et al.
    PMID: 11414406
    Meningitis due to an invasive Haemophilus influenzae type b (Hib) infection, has been previously perceived to be relatively uncommon in Asia. However, the incidence of disease and its impact may have been underestimated. In addition to a lack of microbiological facilities in some hospitals, difficulties in culturing the organism and the widespread use of antibiotics may have hidden the true incidence of the disease in some countries. Furthermore, the reported disease burden probably underestimates the incidence of Hib pneumonia. The epidemiology of invasive Hib disease for various Asian nations is reviewed in this paper. Hospital-based studies show that Hib is a major cause of bacterial meningitis and/or pneumonia in the Philippines, India, Thailand, Malaysia, Indonesia and Vietnam. Singapore and Hong Kong have a low incidence of infection compared with Western and other Asian nations. This low incidence is not due to a higher level of natural protective antibodies, but may be related to an interaction between environmental and genetic factors. Therefore the widespread belief that Hib infection is unimportant in Asia does not refer to Asia as a whole and possibly to Chinese patients only, and failure to recognize this has serious implications. The inclusion of Hib vaccine in the routine infant immunization schedule in many industrialized nations has significantly reduced the incidence of invasive disease. Recent studies have shown Hib vaccination is also effective in preventing invasive disease in children in developing countries. While population-based data may be required to confirm the need for public-funded infant Hib immunization in Asia, its introduction in countries with a high incidence of Hib meningitis and/or pneumonia has the potential to significantly improve pediatric health and survival.
    Matched MeSH terms: Haemophilus Vaccines/administration & dosage
  12. Chandrasekaran S, Kennett L, Yeap PC, Muniandy N, Rani B, Mukkur TK
    Vet Microbiol, 1994 Aug 01;41(3):213-9.
    PMID: 7975147
    Two of the three buffaloes immunized with a non-adjuvanted broth bacterin were found to be protected against experimental challenge at 6 weeks but not at 3 months post-challenge. Similarly all buffaloes (4/4) immunized with alum-precipitated vaccine were protected at 6 months but only 1 of the 2 vaccinated animals were protected at 12 months post-immunization. On the other hand, buffaloes immunized with an oil adjuvant and a double emulsion vaccine were completely protected at 12 months post-immunization. Statistically significant differences between immunized versus non-immune animals became evident at 3 months post-immunization, although analysis of cumulative antibody titres of pre-challenge sera of vaccinated buffaloes surviving versus those succumbing to experimental challenge revealed significant by higher antibody titres in the former as compared to the latter group. These results suggested that there was a relationship between ELISA antibody titres and active protection in buffaloes. There also appeared to be a relationship between cutaneous delayed-type hypersensitivity and active protection in buffaloes. Preliminary analysis of the antibody isotype distribution in the pre-challenge sera of 2 buffaloes vaccinated with the oil adjuvant vaccine revealed predominance of IgG1 and IgG2 subclasses whose role in protection against haemorrhagic septicaemia was not eludicated.
    Matched MeSH terms: Bacterial Vaccines/administration & dosage*
  13. Coleman PG, Dye C
    Vaccine, 1996 Feb;14(3):185-6.
    PMID: 8920697
    WHO recommends that 70% of dogs in a population should be immunized to eliminate or prevent outbreaks of rabies. This critical percentage (pc) has been established empirically from observations on the relationship between vaccination coverage and rabies incidence in dog populations around the world. Here, by contrast, we estimate pc by using epidemic theory, together with data available from four outbreaks in urban and rural areas of the USA, Mexico, Malaysia and Indonesia. From the rate of increase of cases at the beginning of these epidemics, we obtain estimates of the basic case reproduction number of infection, R0, in the range 1.62-2.33, implying that pc lies between 39% and 57%. The errors attached to these estimates of pc suggest that the recommended coverage of 70% would prevent a major outbreak of rabies on no fewer than 96.5% of occasions.
    Matched MeSH terms: Rabies Vaccines/administration & dosage*
  14. Zeng W, Halasa-Rappel YA, Baurin N, Coudeville L, Shepard DS
    Vaccine, 2018 01 08;36(3):413-420.
    PMID: 29229427 DOI: 10.1016/j.vaccine.2017.11.064
    Following publication of results from two phase-3 clinical trials in 10 countries or territories, endemic countries began licensing the first dengue vaccine in 2015. Using a published mathematical model, we evaluated the cost-effectiveness of dengue vaccination in populations similar to those at the trial sites in those same Latin American and Asian countries. Our main scenarios (30-year horizon, 80% coverage) entailed 3-dose routine vaccinations costing US$20/dose beginning at age 9, potentially supplemented by catch-up programs of 4- or 8-year cohorts. We obtained illness costs per case, dengue mortality, vaccine wastage, and vaccine administration costs from the literature. We estimated that routine vaccination would reduce yearly direct and indirect illness cost per capita by 22% (from US$10.51 to US$8.17) in the Latin American countries and by 23% (from US$5.78 to US$4.44) in the Asian countries. Using a health system perspective, the incremental cost-effectiveness ratio (ICER) averaged US$4,216/disability-adjusted life year (DALY) averted in the five Latin American countries (range: US$666/DALY in Puerto Rico to US$5,865/DALY in Mexico). In the five Asian countries, the ICER averaged US$3,751/DALY (range: US$1,935/DALY in Malaysia to US$5,101/DALY in the Philippines). From a health system perspective, the vaccine proved to be highly cost effective (ICER under one times the per capita GDP) in seven countries and cost effective (ICER 1-3 times the per capita GDP) in the remaining three countries. From a societal perspective, routine vaccination proved cost-saving in three countries. Including catch-up campaigns gave similar ICERs. Thus, this vaccine could have a favorable economic value in sites similar to those in the trials.
    Matched MeSH terms: Dengue Vaccines/administration & dosage
  15. Muhamad NA, Buang SN, Jaafar S, Jais R, Tan PS, Mustapha N, et al.
    BMC Public Health, 2018 Dec 22;18(1):1402.
    PMID: 30577816 DOI: 10.1186/s12889-018-6316-6
    BACKGROUND: In 2006, 4 years of planning was started by the Ministry of Health, Malaysia (MOH), to implement the HPV (human papillomavirus) vaccination programme. An inter-agency and multi-sectoral collaborations were developed for Malaysia's HPV school-based immunisation programme. It was approved for nationwide school base implementation for 13-year-old girls or first year secondary students in 2010. This paper examines how the various strategies used in the implementation over the last 7 years (2010-2016) that unique to Malaysia were successful in achieving optimal coverage of the target population.

    METHODS: Free vaccination was offered to school girls in secondary school (year seven) in Malaysia, which is usually at the age of 13 in the index year. All recipients of the HPV vaccine were identified through school enrolments obtained from education departments from each district in Malaysia. A total of 242,638 girls aged between 12 to 13 years studying in year seven were approached during the launch of the program in 2010. Approximately 230,000 girls in secondary schools were offered HPV vaccine per year by 646 school health teams throughout the country from 2010 to 2016.

    RESULTS: Parental consent for their daughters to receive HPV vaccination at school was very high at 96-98% per year of the programme. Of those who provided consent, over 99% received the first dose each year and 98-99% completed the course per year. Estimated population coverage for the full vaccine course, considering also those not in school, is estimated at 83 to 91% per year. Rates of adverse events reports following HPV vaccination were low at around 2 per 100,000 and the majority was injection site reactions.

    CONCLUSION: A multisectoral and integrated collaborative structure and process ensured that the Malaysia school-based HPV immunisation programme was successful and sustained through the programme design, planning, implementation and monitoring and evaluation. This is a critical factor contributing to the success and sustainability of the school-based HPV immunisation programme with very high coverage.

    Matched MeSH terms: Papillomavirus Vaccines/administration & dosage*
  16. Xian TH, Parasuraman S, Sinniah K, Ravichandran M, Prabhakaran G
    Vaccine, 2019 01 29;37(5):711-720.
    PMID: 30630696 DOI: 10.1016/j.vaccine.2018.12.027
    The repeated dose toxicity of a prototype cold chain-free, live, attenuated oral cholera vaccine containing 5 × 106 CFU/mL of the VCUSM14P strain was evaluated in Sprague Dawley (SD) rats (single dose administered daily for 30 days) to ascertain its safety for clinical use. Repeated dose toxicity studies for cholera vaccines in the literature have administered 2 or 3 fixed doses at 7, 14, 21 or 69 day intervals. The present study reports an evaluation of 30 repeated doses of cholera vaccine administered at three different concentrations (Group II (1.25 × 106 CFU), Group III (2.5 × 106 CFU) and Group IV (5 × 106 CFU)) in SD rats. The liquid vaccine was administered orally to the rats with the respective dose every day, and normal saline was administered to the control group (Group I). No significant difference (P > 0.05) was observed in the body weights and biochemical parameters of the rats after 15 and 30 repeated doses compared to those of the control group. However, compared to those of Group I, a significant increase (P 
    Matched MeSH terms: Cholera Vaccines/administration & dosage*
  17. Wong LP, Han L, Li H, Zhao J, Zhao Q, Zimet GD
    Hum Vaccin Immunother, 2019;15(7-8):1533-1540.
    PMID: 31017500 DOI: 10.1080/21645515.2019.1611157
    The introduction of human papillomavirus (HPV) vaccination in China aims to prevent HPV infection in all women. The issues that China might face include high cost of vaccines made in other countries, shortage in HPV vaccine supply, negative events attributed to vaccination (whether justified or not) that jeopardizes the general public's confidence in the HPV vaccine, cultural and literacy barriers, and sensitivity to receiving a vaccine for a sexually transmitted disease. Ensuring the effective delivery of the HPV vaccine in China, a country with vast economic, geographical, and cultural complexities, will require a commitment of significant resources. In light of the high price of imported vaccines, the availability of locally manufactured HPV vaccines would greatly facilitate the national HPV vaccination program. New evidence supporting the efficacy of a two-dose regime in younger adolescents would also be advantageous in terms of affordability and logistical simplicity of vaccine administration. Furthermore, it would potentially enhance the compliance and uptake, especially for hard to reach women in remote regions.
    Matched MeSH terms: Papillomavirus Vaccines/administration & dosage*
  18. Bornstein J, Roux S, Kjeld Petersen L, Huang LM, Dobson SR, Pitisuttithum P, et al.
    Pediatrics, 2021 01;147(1).
    PMID: 33386332 DOI: 10.1542/peds.2019-4035
    BACKGROUND AND OBJECTIVES: Human papillomavirus (HPV) antibody responses to the 9-valent human papillomavirus (9vHPV) vaccine among girls and boys (aged 9-14 years) receiving 2-dose regimens (months 0, 6 or 0, 12) were noninferior to a 3-dose regimen (months 0, 2, 6) in young women (aged 16-26 years) 4 weeks after last vaccination in an international, randomized, open-label trial (NCT01984697). We assessed response durability through month 36.

    METHODS: Girls received 2 (months 0 and 6 [0, 6]: n = 301; months 0 and 12 [0, 12]: n = 151) or 3 doses (months 0,2, and 6 [0, 2, 6]: n = 301); boys received 2 doses ([0, 6]: n = 301; [0, 12]: n = 150); and young women received 3 doses ([0, 2, 6]: n = 314) of 9vHPV vaccine. Anti-HPV geometric mean titers (GMTs) were assessed by competitive Luminex immunoassay (cLIA) and immunoglobulin G-Luminex immunoassay (IgG-LIA) through month 36.

    RESULTS: Anti-HPV GMTs were highest 1 month after the last 9vHPV vaccine regimen dose, decreased sharply during the subsequent 12 months, and then decreased more slowly. GMTs 2 to 2.5 years after the last regimen dose in girls and boys given 2 doses were generally similar to or greater than GMTs in young women given 3 doses. Across HPV types, most boys and girls who received 2 doses (cLIA: 81%-100%; IgG-LIA: 91%-100%) and young women who received 3 doses (cLIA: 78%-98%; IgG-LIA: 91%-100%) remained seropositive 2 to 2.5 years after the last regimen dose.

    CONCLUSIONS: Antibody responses persisted through 2 to 2.5 years after the last dose of a 2-dose 9vHPV vaccine regimen in girls and boys. In girls and boys, antibody responses generated by 2 doses administered 6 to 12 months apart may be sufficient to induce high-level protective efficacy through at least 2 years after the second dose.

    Matched MeSH terms: Papillomavirus Vaccines/administration & dosage*
  19. Izzati Mat Rani NN, Alzubaidi ZM, Azhari H, Mustapa F, Iqbal Mohd Amin MC
    Eur J Pharmacol, 2021 Jun 05;900:174009.
    PMID: 33722591 DOI: 10.1016/j.ejphar.2021.174009
    Over the years, extensive studies on erythrocytes, also known as red blood cells (RBCs), as a mechanism for drug delivery, have been explored mainly because the cell itself is the most abundant and has astonishing properties such as a long life span of 100-120 days, low immunogenicity, good biocompatibility, and flexibility. There are various types of RBC-based systems for drug delivery, including those that are genetically engineered, non-genetically engineered RBCs, as well as employing erythrocyte as nanocarriers for drug loading. Although promising, these systems are still in an early development stage. In this review, we aimed to highlight the development of biomimicking RBC-based drug and vaccine delivery systems, as well as the loading methods with illustrative examples. Drug-erythrocyte associations will also be discussed and highlighted in this review. We have highlighted the possibility of exploiting erythrocytes for the sustained delivery of drugs and vaccines, encapsulation of these biological agents within the erythrocyte or coupling to the surface of carrier erythrocytes, and provided insights on genetically- and non-genetically engineered erythrocytes-based strategies. Erythrocytes have been known as effective cellular carriers for therapeutic moieties for several years. Herein, we outline various loading methods that can be used to reap the benefits of these natural carriers. It has been shown that drugs and vaccines can be delivered via erythrocytes but it is important to select appropriate methods for increasing the drug encapsulated or conjugated on the surface of the erythrocyte membrane. The outlined examples will guide the selection of the most effective method as well as the impact of using erythrocytes as delivery systems for drugs and vaccines.
    Matched MeSH terms: Vaccines/administration & dosage*
  20. Aljumaili OA, Bello MB, Yeap SK, Omar AR, Ideris A
    Onderstepoort J Vet Res, 2020 Sep 28;87(1):e1-e7.
    PMID: 33054260 DOI: 10.4102/ojvr.v87i1.1865
    Despite the availability of Newcastle disease (ND) vaccines for more than six decades, disease outbreaks continue to occur with huge economic consequences to the global poultry industry. The aim of this study is to develop a safe and effective inactivated vaccine based on a recently isolated Newcastle disease virus (NDV) strain IBS025/13 and evaluate its protective efficacy in chicken following challenge with a highly virulent genotype VII isolate. Firstly, high titre of IBS025/13 was exposed to various concentrations of binary ethylenimine (BEI) to determine the optimal conditions for complete inactivation of the virus. The inactivated virus was then prepared in form of a stable water-in-oil emulsion of black seed oil (BSO) or Freund's incomplete adjuvant (FIA) and used as vaccines in specific pathogen-free chicken. Efficacy of various vaccine preparations was also evaluated based on the ability of the vaccine to protect against clinical disease, mortality and virus shedding following challenge with highly virulent genotype\VII NDV isolate. The results indicate that exposure of NDV IBS025/13 to 10 mM of BEI for 21 h at 37 °C could completely inactivate the virus without tempering with the structural integrity of the viral hemagglutin-neuraminidase protein. More so, the inactivated vaccines adjuvanted with either BSO- or FIA-induced high hemagglutination inhibition antibody titre that protected the vaccinated birds against clinical disease and in some cases virus shedding, especially when used together with live attenuated vaccines. Thus, genotype VII-based NDV-inactivated vaccines formulated in BSO could substantially improve poultry disease control particularly when combined with live attenuated vaccines.
    Matched MeSH terms: Viral Vaccines/administration & dosage*
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links