Displaying publications 1 - 20 of 25 in total

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  1. Fulltext A novel nano therapeutic using convalescent plasma derived exosomal (CPExo) for COVID-19: A combined hyperactive immune modulation and diagnostics
    Anand K, Vadivalagan C, Joseph JS, Singh SK, Gulati M, Shahbaaz M, et al.
    Chem Biol Interact, 2021 Aug 01;344:109497.
    PMID: 33991505 DOI: 10.1016/j.cbi.2021.109497
    Extracellular vesicles like exosomes are important therapeutic tactics for treating COVID -19. By utilizing convalescent plasma derived exosomes (CPExo) from COVID-19 recovered persistence could accelerate the treatment strategies in the current state of affairs. Adequate literature has shown that administering the exosome to the in vivo system could be beneficial and could target the pathogens in an effective and precise manner. In this hypothesis we highlight the CPExo instead of convalescent plasma (CP), perhaps to dispense of exosomes are gratified and it's more effectively acquired immune response conferral through antibodies. COVID-19 convalescent plasma has billions of exosomes and it has aptitudes to carry molecular constituents like proteins, lipids, RNA and DNA, etc. Moreover, exosomes are capable of recognizing antigens with adequate sensitivity and specificity. Many of these derivatives could trigger an immune modulation into the cells and act as an epigenetic inheritor response to target pathogens through RNAs. COIVID-19 resistance activated plasma-derived exosomes are either responsible for the effects of plasma beyond the contained immune antibodies or could be inhibitory. The proposed hypothesis suggests that preselecting the plasma-derived antibodies and RNAs merged exosomes would be an optimized therapeutic tactic for COVID-19 patients. We suggest that, the CPExo has a multi-potential effect for treatment efficacy by acting as immunotherapeutic, drug carrier, and diagnostic target with noncoding genetic materials as a biomarker.
    Matched MeSH terms: DNA/immunology
  2. Sensing Self and Non-Self DNA by Innate Immune Receptors and Their Signaling Pathways
    Sok SPM, Ori D, Nagoor NH, Kawai T
    Crit. Rev. Immunol., 2018;38(4):279-301.
    PMID: 30806244 DOI: 10.1615/CritRevImmunol.2018026540
    The innate immune system serves as the first line of defense to protect the host from pathogen infection. As a first step, the pattern recognition receptors (PRRs) recognize pathogen-associated molecular patterns (PAMPs), such as non-self DNA derived from pathogens, and damage-associated molecular patterns (DAMPs), such as self DNA released from damaged or injured cells. Sensing of such DNAs elicits innate immune responses through the production of type I interferons (IFNs) and proinflammatory cytokines resulting from the activation of interferon regulatory factor 3 (IRF3) and nuclear factor kappa B (NF-κB), respectively. These cytokines are key players in interlinking innate and adaptive immune responses. However, defects in DNA sensors and their signaling cascades lead to dysregulation of immune responses, autoimmune diseases, and cancer progression. Here we provide an update on DNA signaling pathways in response to pathogen infection and cell injury, and on the roles of regulators in governing the immune system and maintaining host homeostasis. We also discuss the evasion of immunosurveillance by pathogens.
    Matched MeSH terms: DNA/immunology*
  3. DNA vaccination with a plasmid encoding LACK-TSA fusion against Leishmania major infection in BALB/c mice
    Maspi N, Ghaffarifar F, Sharifi Z, Dalimi A, Khademi SZ
    Malays J Pathol, 2017 Dec;39(3):267-275.
    PMID: 29279589
    Vaccination would be the most important strategy for the prevention and elimination of leishmaniasis. The aim of the present study was to compare the immune responses induced following DNA vaccination with LACK (Leishmania analogue of the receptor kinase C), TSA (Thiol-specific-antioxidant) genes alone or LACK-TSA fusion against cutaneous leishmaniasis (CL). Cellular and humoral immune responses were evaluated before and after challenge with Leishmania major (L. major). In addition, the mean lesion size was also measured from 3th week post-infection. All immunized mice showed a partial immunity characterized by higher interferon (IFN)-γ and Immunoglobulin G (IgG2a) levels compared to control groups (p<0.05). IFN-γ/ Interleukin (IL)-4 and IgG2a/IgG1 ratios demonstrated the highest IFN-γ and IgG2a levels in the group receiving LACK-TSA fusion. Mean lesion sizes reduced significantly in all immunized mice compared with control groups at 7th week post-infection (p<0.05). In addition, there was a significant reduction in mean lesion size of LACK-TSA and TSA groups than LACK group after challenge (p<0.05). In the present study, DNA immunization promoted Th1 immune response and confirmed the previous observations on immunogenicity of LACK and TSA antigens against CL. Furthermore, this study demonstrated that a bivalent vaccine can induce stronger immune responses and protection against infectious challenge with L. major.
    Matched MeSH terms: Vaccines, DNA/immunology*
  4. Fulltext Mucosal genetic immunization through microsphere-based oral carriers
    Rosli R, Nograles N, Hanafi A, Nor Shamsudin M, Abdullah S
    Hum Vaccin Immunother, 2013 Oct;9(10):2222-7.
    PMID: 24051430 DOI: 10.4161/hv.25325
    Polymeric carriers in the form of cellulose acetate phthalate (CAP) and alginate (ALG) microspheres were used for encapsulation of plasmid DNA for oral mucosal immunization. Access into the intestinal mucosa by pVAX1 eukaryotic expression plasmid vectors carrying gene-coding sequences, either for the cholera enterotoxin B subunit (ctxB) immunostimulatory antigen or the green fluorescent protein (GFP), delivered from both types of microsphere carriers were examined in orally immunized BALB/c mice. Demonstration of transgene protein expression and IgA antibody responses at local mucosal sites suggest immunological response to a potential oral DNA vaccine formulated within the microsphere carriers.
    Matched MeSH terms: Vaccines, DNA/immunology
  5. Anti-nucleosome antibodies as a disease activity marker in patients with systemic lupus erythematosus
    Suleiman S, Kamaliah D, Nadeem A, Naing NN, Che Maraina CH
    Int J Rheum Dis, 2009 Jul;12(2):100-6.
    PMID: 20374326 DOI: 10.1111/j.1756-185X.2009.01391.x
    AIM: To measure the level of anti-nucleosome antibodies in systemic lupus erythematosus (SLE) patients, to determine the sensitivity and the specificity of these antibodies in the diagnosis of the disease and to evaluate the relationship between the levels of anti-nucleosome antibodies, anti-dsDNA (double-stranded DNA) and SLE disease activity.
    METHODS: A cross-sectional study was conducted. All patients attended either a medical specialist clinic or were admitted to the medical wards of Hospital Universiti Sains Malaysia with the diagnosis of SLE (n = 90), other connective tissue diseases (n = 45) or were normal controls (n = 90) within the period from July 2004 until September 2005. They were tested for anti-nucleosome antibodies by enzyme-linked immunosorbent assay and anti-DNA antibodies by immunofluorescence. SLE disease activity was evaluated by SLE disease activity index (SLEDAI) score.
    RESULTS: Out of 90 SLE patients, anti-nucleosome antibodies were positive in 47 (52.2%) patients, whereas these antibodies were positive in three (6.7%) patients with other connective tissue diseases. Anti-dsDNA antibodies were positive in 33 (36.7%) SLE patients, whereas these antibodies were positive in four (8.9%) patients with other connective tissue diseases. Anti-nucleosome antibodies were positive in 40 (97.6%) patients with active SLE, whereas these antibodies were positive in seven (14.3%) patients with inactive SLE. Anti-nucleosome antibodies had a stronger correlation than anti-dsDNA antibodies with SLEDAI score. There was a significant association between anti-nucleosome antibodies and disease activity.
    CONCLUSION: Anti-nucleosome antibodies test is highly sensitive and specific for the diagnosis of SLE, especially when the anti-dsDNA antibodies are absent. They are additional disease activity markers in the assessment of SLE disease activity.
    Matched MeSH terms: DNA/immunology
  6. Fulltext Kikuchi's lymphadenitis (necrotizing lymphadenitis) and systemic lupus erythematosus: a case report
    Fernandez SH
    Malays J Pathol, 2000 Jun;22(1):25-9.
    PMID: 16329534
    A 26-year-old Indian lady was admitted for lower abdominal pain, diarrhoea, vomiting, fever and cough. The initial diagnosis was that of peritonitis secondary to ruptured or perforated viscus with lobar pneumonia. On laparotomy, she was found to have necrotizing or Kikuchi's lymphadenitis of the abdominal lymph nodes. The initial two antinuclear antibody (ANA) results came back negative. She was diagnosed to have systemic lupus erythematosus (SLE) when the third sample for ANA came back positive and the double-stranded DNA (dsDNA) antibody test was homogenously positive. This case illustrates a need to be aware that necrotizing lymphadenitis can precede the onset of systemic lupus erythematosus.
    Matched MeSH terms: DNA/immunology
  7. Fulltext DNA Vaccines Targeting Novel Cancer-Associated Antigens Frequently Expressed in Head and Neck Cancer Enhance the Efficacy of Checkpoint Inhibitor
    Wang C, Zainal NS, Chai SJ, Dickie J, Gan CP, Zulaziz N, et al.
    Front Immunol, 2021;12:763086.
    PMID: 34733290 DOI: 10.3389/fimmu.2021.763086
    HPV-independent head and neck squamous cell carcinoma (HNSCC) is a common cancer globally. The overall response rate to anti-PD1 checkpoint inhibitors (CPIs) in HNSCC is ~16%. One major factor influencing the effectiveness of CPI is the level of tumor infiltrating T cells (TILs). Converting TILlow tumors to TILhigh tumors is thus critical to improve clinical outcome. Here we describe a novel DNA vaccines to facilitate the T-cell infiltration and control tumor growth. We evaluated the expression of target antigens and their respective immunogenicity in HNSCC patients. The efficacy of DNA vaccines targeting two novel antigens were evaluated with or without CPI using a syngeneic model. Most HNSCC patients (43/44) co-expressed MAGED4B and FJX1 and their respective tetramer-specific T cells were in the range of 0.06-0.12%. In a preclinical model, antigen-specific T cells were induced by DNA vaccines and increased T cell infiltration into the tumor, but not MDSC or regulatory T cells. The vaccines inhibited tumor growth and improved the outcome alone and upon combination with anti-PD1 and resulted in tumor clearance in approximately 75% of mice. Pre-existence of MAGED4B and FJX1-reactive T cells in HNSCC patients suggests that these widely expressed antigens are highly immunogenic and could be further expanded by vaccination. The DNA vaccines targeting these antigens induced robust T cell responses and with the anti-PD1 antibody conferring excellent tumor control. This opens up an opportunity for combination immunotherapy that might benefit a wider population of HNSCC patients in an antigen-specific manner.
    Matched MeSH terms: Vaccines, DNA/immunology*
  8. Fulltext Co-administration of avian influenza virus H5 plasmid DNA with chicken IL-15 and IL-18 enhanced chickens immune responses
    Lim KL, Jazayeri SD, Yeap SK, Alitheen NB, Bejo MH, Ideris A, et al.
    BMC Vet Res, 2012;8:132.
    PMID: 22866758 DOI: 10.1186/1746-6148-8-132
    DNA vaccines offer several advantages over conventional vaccines in the development of effective vaccines against avian influenza virus (AIV). However, one of the limitations of the DNA vaccine in poultry is that it induces poor immune responses. In this study, chicken interleukin (IL) -15 and IL-18 were used as genetic adjuvants to improve the immune responses induced from the H5 DNA vaccination in chickens. The immunogenicity of the recombinant plasmid DNA was analyzed based on the antibody production, T cell responses and cytokine production, following inoculation in 1-day-old (Trial 1) and 14-day-old (Trial 2) specific-pathogen-free chickens. Hence, the purpose of the present study was to explore the role of chicken IL-15 and IL-18 as adjuvants following the vaccination of chickens with the H5 DNA vaccine.
    Matched MeSH terms: Vaccines, DNA/immunology
  9. Development of a DNA vaccine against chicken anemia virus by using a bicistronic vector expressing VP1 and VP2 proteins of CAV
    Moeini H, Omar AR, Rahim RA, Yusoff K
    Comp Immunol Microbiol Infect Dis, 2011 May;34(3):227-36.
    PMID: 21146874 DOI: 10.1016/j.cimid.2010.11.006
    In the present study, we describe the development of a DNA vaccine against chicken anemia virus. The VP1 and VP2 genes of CAV were amplified and cloned into pBudCE4.1 to construct two DNA vaccines, namely, pBudVP1 and pBudVP2-VP1. In vitro and in vivo studies showed that co-expression of VP1 with VP2 are required to induce significant levels of antibody against CAV. Subsequently, the vaccines were tested in 2-week-old SPF chickens. Chickens immunized with the DNA-plasmid pBudVP2-VP1 showed positive neutralizing antibody titer against CAV. Furthermore, VP1-specific proliferation induction of splenocytes and also high serum levels of Th1 cytokines, IL-2 and IFN-γ were detected in the pBudVP2-VP1-vaccinated chickens. These results suggest that the recombinant DNA plasmid co-expressing VP1 and VP2 can be used as a potential DNA vaccine against CAV.
    Matched MeSH terms: Vaccines, DNA/immunology*
  10. Cardamonin from Alpinia rafflesiana inhibits inflammatory responses in IFN-γ/LPS-stimulated BV2 microglia via NF-κB signalling pathway
    Chow YL, Lee KH, Vidyadaran S, Lajis NH, Akhtar MN, Israf DA, et al.
    Int Immunopharmacol, 2012 Apr;12(4):657-65.
    PMID: 22306767 DOI: 10.1016/j.intimp.2012.01.009
    The increasing prevalence of neurodegenerative diseases has prompted investigation into innovative therapeutics over the last two decades. Non-steroidal anti-inflammatory drugs (NSAIDs) are among the therapeutic choices to control and suppress the symptoms of neurodegenerative diseases. However, NSAIDs-associated gastropathy has hampered their long term usage despite their clinical advancement. On the natural end of the treatment spectrum, our group has shown that cardamonin (2',4'-dihydroxy-6'-methoxychalcone) isolated from Alpinia rafflesiana exerts potential anti-inflammatory activity in activated macrophages. Therefore, we further explored the anti-inflammatory property of cardamonin as well as its underlying mechanism of action in IFN-γ/LPS-stimulated microglial cells. In this investigation, cardamonin shows promising anti-inflammatory activity in microglial cell line BV2 by inhibiting the secretion of pro-inflammatory mediators including nitric oxide (NO), prostaglandin E(2) (PGE(2)), tumour necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6). The inhibition of NO and PGE(2) by cardamonin are resulted from the reduced expression of inducible nitric oxide synthase (iNOS) and cycloxygenase-2 (COX-2), respectively. Meanwhile the suppressive effects of cardamonin on TNF-α, IL-1β and IL-6 were demonstrated at both protein and mRNA levels, thus indicating the interference of upstream signal transduction pathway. Our results also validate that cardamonin interrupts nuclear factor-kappa B (NF-κB) signalling pathway via attenuation of NF-κB DNA binding activity. Interestingly, cardamonin also showed a consistent suppressive effect on the cell surface expression of CD14. Taken together, our experimental data provide mechanistic insights for the anti-inflammatory actions of cardamonin in BV2 and thus suggest a possible therapeutic application of cardamonin for targeting neuroinflammatory disorders.
    Matched MeSH terms: DNA/immunology
  11. Antigenic potential of a recombinant polyvalent DNA vaccine against pathogenic leptospiral infection
    Garba B, Bahaman AR, Zakaria Z, Bejo SK, Mutalib AR, Bande F, et al.
    Microb Pathog, 2018 Nov;124:136-144.
    PMID: 30138761 DOI: 10.1016/j.micpath.2018.08.028
    Leptospirosis is a serious epidemic disease caused by pathogenic Leptospira species. The disease is endemic in most tropical and sub-tropical regions of the world. Currently, there is no effective polyvalent vaccine for prevention against most of the circulating serovars. Moreover, development of an efficient leptospiral vaccine capable of stimulating cross-protective immune responses against a wide range of serovars remains a daunting challenge. This, in part, is associated with the extensive diversity and variation of leptospiral serovars from region to region. In this study, a multi-epitope DNA vaccine encoding highly immunogenic epitopes from LipL32 and LipL41 was designed using in-silico approach. The DNA encoding antigenic epitopes was constructed from conserved pathogenic Leptospira genes (LipL32 and LipL41). Immunization of golden Syrian hamsters with the multi-epitope chimeric DNA vaccine resulted in the production of both agglutinating and neutralizing antibodies as evidence by MAT and in-vitro growth inhibition tests respectively. The antibodies produced reacted against eight different serovars and significantly reduced renal colonization following in vivo challenge. The vaccine was also able to significantly reduce renal colonization which is a very important factor responsible for persistence of leptospires among susceptible and reservoir animal hosts. In conclusion, the leptospiral multi-epitope chimeric DNA vaccine can serve as a potentially effective and safe vaccine against infection with different pathogenic leptospiral serovars.
    Matched MeSH terms: Vaccines, DNA/immunology*
  12. Potential DNA Vaccine for Haemorrhagic Septiceamia Disease
    Chelliah S, Velappan RD, Lim KT, Swee CWK, Nor Rashid N, Rothan HA, et al.
    Mol Biotechnol, 2020 May;62(5):289-296.
    PMID: 32185600 DOI: 10.1007/s12033-020-00244-0
    Pasteurella multocida is the main cause of haemorrhagic septicaemia (HS) outbreak in livestock, such as cattle and buffaloes. Conventional vaccines such as alum-precipitated or oil-adjuvant broth bacterins were injected subcutaneously to provide protection against HS. However, the immunity developed is only for short term and needed to be administered frequently. In our previous study, a short gene fragment from Pasteurella multocida serotype B was obtained via shotgun cloning technique and later was cloned into bacterial expression system. pQE32-ABA392 was found to possess immunogenic activity towards HS when tested in vivo in rat model. In this study, the targeted gene fragment of ABA392 was sub-cloned into a DNA expression vector pVAX1 and named as pVAX1-ABA392. The new recombinant vaccine was stable and expressed on mammalian cell lines. Serum sample collected from a group of vaccinated rats for ELISA test shows that the antibody in immunized rats was present at high titer and can be tested as a vaccine candidate with challenge in further studies. This successful recombinant vaccine is immunogenic and potentially could be used as vaccine in future against HS.
    Matched MeSH terms: Vaccines, DNA/immunology
  13. Fulltext Association of anti-CLIC2 and anti-HMGB1 autoantibodies with higher disease activity in systemic lupus erythematosus patients
    Syahidatulamali CS, Wan Syamimee WG, Azwany YN, Wong KK, Che Maraina CH
    J Postgrad Med, 2017 9 2;63(4):257-261.
    PMID: 28862243 DOI: 10.4103/jpgm.JPGM_499_16
    BACKGROUND: Systemic lupus erythematosus (SLE) is a systemic autoimmune disease characterized by numerous autoantibodies. In this study, we investigated the presence of anti-chloride intracellular channel 2 (anti-CLIC2) and anti-high mobility group box 1 (anti-HMGB1) autoantibodies in SLE patients (n = 43) versus healthy controls ([HCs] n = 43), and their association with serological parameters (antinuclear antibody [ANA], anti-double-stranded DNA [anti-dsDNA], and C-reactive protein [CRP]) and disease activity using Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) score (active or inactive).

    SETTINGS AND DESIGN: Case-control study at Rheumatology Clinic of Universiti Sains Malaysia Hospital.

    SUBJECTS AND METHODS: The sera of SLE patients and HCs were tested for the presence of anti-CLIC2 and anti-HMGB1 autoantibodies using human recombinant proteins and ELISA methodologies. Other serological parameters were evaluated according to routine procedures, and patients' demographic and clinical data were obtained.

    STATISTICAL ANALYSIS: Mann-Whitney U-test, Chi-square test, Fisher's exact test, and receiver operating characteristic analysis.

    RESULTS: Anti-CLIC2 autoantibody levels were significantly higher in SLE patients compared to HCs (P = 0.0035), whereas anti-HMGB1 autoantibody levels were not significantly elevated (P = 0.7702). Anti-CLIC2 and anti-HMGB1 autoantibody levels were not associated with ANA pattern, anti-dsDNA, and CRP. Interestingly, SLEDAI score (≥6) was associated with anti-CLIC2 (P = 0.0046) and with anti-HMGB1 (P = 0.0091) autoantibody levels.

    CONCLUSION: Our findings support the potential of using anti-CLIC2 autoantibodies as a novel biomarker for SLE patients. Both anti-CLIC2 and anti-HMGB1 autoantibody levels demonstrated potential in monitoring SLE disease activity.

    Matched MeSH terms: DNA/immunology
  14. Fulltext Preparation, characterization, and in ovo vaccination of dextran-spermine nanoparticle DNA vaccine coexpressing the fusion and hemagglutinin genes against Newcastle disease
    Firouzamandi M, Moeini H, Hosseini SD, Bejo MH, Omar AR, Mehrbod P, et al.
    Int J Nanomedicine, 2016;11:259-67.
    PMID: 26834470 DOI: 10.2147/IJN.S92225
    Plasmid DNA (pDNA)-based vaccines have emerged as effective subunit vaccines against viral and bacterial pathogens. In this study, a DNA vaccine, namely plasmid internal ribosome entry site-HN/F, was applied in ovo against Newcastle disease (ND). Vaccination was carried out using the DNA vaccine alone or as a mixture of the pDNA and dextran-spermine (D-SPM), a nanoparticle used for pDNA delivery. The results showed that in ovo vaccination with 40 μg pDNA/egg alone induced high levels of antibody titer (P<0.05) in specific pathogen-free (SPF) chickens at 3 and 4 weeks postvaccination compared to 2 weeks postvaccination. Hemagglutination inhibition (HI) titer was not significantly different between groups injected with 40 μg pDNA + 64 μg D-SPM and 40 μg pDNA at 4 weeks postvaccination (P>0.05). Higher antibody titer was observed in the group immunized with 40 μg pDNA/egg at 4 weeks postvaccination. The findings also showed that vaccination with 40 μg pDNA/egg alone was able to confer protection against Newcastle disease virus strain NDIBS002 in two out of seven SPF chickens. Although the chickens produced antibody titers 3 weeks after in ovo vaccination, it was not sufficient to provide complete protection to the chickens from lethal viral challenge. In addition, vaccination with pDNA/D-SPM complex did not induce high antibody titer when compared with naked pDNA. Therefore, it was concluded that DNA vaccination with plasmid internal ribosome entry site-HN/F can be suitable for in ovo application against ND, whereas D-SPM is not recommended for in ovo gene delivery.
    Matched MeSH terms: Vaccines, DNA/immunology
  15. Fulltext Pediatric systemic lupus erythematosus. Retrospective analysis of clinico-laboratory parameters and their association with Systemic Lupus Erythematosus Disease Activity Index score
    Nazri SKSM, Wong KK, Hamid WZWA
    Saudi Med J, 2018 Jun;39(6):627-631.
    PMID: 29915860 DOI: 10.15537/smj.2018.6.22112
    OBJECTIVES: To elucidate the clinico-laboratory characteristics associated with pediatric systemic lupus erythematosus (pSLE) patients with higher Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) score in a retrospective cohort of pSLE patients.

    METHODS: A retrospective study involving 32 pSLE patients was conducted at Hospital Universiti Sains Malaysia, Kelantan, Malaysia between 2006 and 2017.

    RESULTS: Within the group of 32 pSLE patients, 23 were girls and 9 were boys (3:1 ratio). The most common symptom was renal disorder (n=21; 65.6%) followed by malar rash (n=9; 28.1%), oral ulcers (n=7; 21.9%), prolonged fever (n=5; 15.6%) and arthritis (n=4; 12.5%). Antinuclear antibodies (ANA) were detected in all patients and 25 patients (78.1%) were positive for anti-double stranded DNA (anti-dsDNA) antibodies. Eighteen (56.3%) patients had active SLE (SLEDAI ≥6), and these patients were significantly associated with heavy pyuria (p=0.004), a high ANA concentration (1:160; p=0.040, 1:320; p=0.006), elevated ESR (p=0.006), low C3 levels (p=0.008), oral ulcers (p=0.010), heavy hematuria (p=0.017) and heavy proteinuria (p=0.017), lupus erythematosus (LE)-nonspecific lesion manifestations (p=0.019) and malar rash (p=0.044).

    CONCLUSION: Pediatric systemic lupus erythematosus patients with higher SLEDAI score were most significantly associated with pyuria, high ANA titers, and elevated ESR.
    Matched MeSH terms: DNA/immunology
  16. Fulltext Cytosolic DNA sensing through cGAS and STING is inactivated by gene mutations in pangolins
    Fischer H, Tschachler E, Eckhart L
    Apoptosis, 2020 Aug;25(7-8):474-480.
    PMID: 32533513 DOI: 10.1007/s10495-020-01614-4
    The release of DNA into the cytoplasm upon damage to the nucleus or during viral infection triggers an interferon-mediated defense response, inflammation and cell death. In human cells cytoplasmic DNA is sensed by cyclic GMP-AMP Synthase (cGAS) and Absent In Melanoma 2 (AIM2). Here, we report the identification of a "natural knockout" model of cGAS. Comparative genomics of phylogenetically diverse mammalian species showed that cGAS and its interaction partner Stimulator of Interferon Genes (STING) have been inactivated by mutations in the Malayan pangolin whereas other mammals retained intact copies of these genes. The coding sequences of CGAS and STING1 are also disrupted by premature stop codons and frame-shift mutations in Chinese and tree pangolins, suggesting that expression of these genes was lost in a common ancestor of all pangolins that lived more than 20 million years ago. AIM2 is retained in a functional form in pangolins whereas it is inactivated by mutations in carnivorans, the phylogenetic sister group of pangolins. The deficiency of cGAS and STING points to the existence of alternative mechanisms of controlling cytoplasmic DNA-associated cell damage and viral infections in pangolins.
    Matched MeSH terms: DNA/immunology
  17. Cytotoxicity and immunological responses following oral vaccination of nanoencapsulated avian influenza virus H5 DNA vaccine with green synthesis silver nanoparticles
    Jazayeri SD, Ideris A, Zakaria Z, Shameli K, Moeini H, Omar AR
    J Control Release, 2012 Jul 10;161(1):116-23.
    PMID: 22549012 DOI: 10.1016/j.jconrel.2012.04.015
    DNA formulations provide the basis for safe and cost effective vaccine. Low efficiency is often observed in the delivery of DNA vaccines. In order to assess a new strategy for oral DNA vaccine formulation and delivery, plasmid encoding hemagglutinin (HA) gene of avian influenza virus, A/Ck/Malaysia/5858/04 (H5N1) (pcDNA3.1/H5) was formulated using green synthesis of sliver nanoparticles (AgNP) with polyethylene glycol (PEG). AgNP were successfully synthesized uniformly dispersed with size in the range of 4 to 18 nm with an average size of 11 nm. Cytotoxicity of the prepared AgNP was investigated in vitro and in vivo using MCF-7 cells and cytokine expression, respectively. At the concentration of -5 log₁₀AgNP, no cytotoxic effects were detected in MCF-7 cells with 9.5% cell death compared to the control. One-day-old specific pathogen-free (SPF) chicks immunized once by oral gavage with 10 μl of pcDNA3.1/H5 (200 ng/ml) nanoencapsulated with 40 μl AgNP (3.7×10⁻² μg of Ag) showed no clinical manifestations. PCR successfully detect the AgNP/H5 plasmid from the duodenum of the inoculated chicken as early as 1h post-immunization. Immunization of chickens with AgNP/H5 enhanced both pro inflammatory and Th1-like expressions, although no significant differences were recorded in the chickens inoculated with AgNP, AgNP/pcDNA3.1 and the control. In addition, serum samples collected from immunized chickens with AgNP/H5 showed rapidly increasing antibody against H5 on day 14 after immunization. The highest average antibody titres were detected on day 35 post-immunization at 51.2±7.5. AgNP/H5 also elicited both CD4+ and CD8+ T cells in the immunized chickens as early as day 14 after immunization, at 7.5±2.0 and 20±1.9 percentage, respectively. Hence, single oral administrations of AgNP/H5 led to induce both the antibody and cell-mediated immune responses as well as enhanced cytokine production.
    Matched MeSH terms: Vaccines, DNA/immunology
  18. Fulltext Improving the potency of DNA vaccine against chicken anemia virus (CAV) by fusing VP1 protein of CAV to Marek's Disease Virus (MDV) type-1 VP22 protein
    Moeini H, Omar AR, Rahim RA, Yusoff K
    Virol J, 2011;8:119.
    PMID: 21401953 DOI: 10.1186/1743-422X-8-119
    Studies have shown that the VP22 gene of Marek's Disease Virus type-1 (MDV-1) has the property of movement between cells from the original cell of expression into the neighboring cells. The ability to facilitate the spreading of the linked proteins was used to improve the potency of the constructed DNA vaccines against chicken anemia virus (CAV).
    Matched MeSH terms: Vaccines, DNA/immunology*
  19. DNA vaccine encoding avian influenza virus H5 and Esat-6 of Mycobacterium tuberculosis improved antibody responses against AIV in chickens
    Oveissi S, Omar AR, Yusoff K, Jahanshiri F, Hassan SS
    Comp Immunol Microbiol Infect Dis, 2010 Dec;33(6):491-503.
    PMID: 19781778 DOI: 10.1016/j.cimid.2009.08.004
    The H5 gene of avian influenza virus (AIV) strain A/chicken/Malaysia/5744/2004(H5N1) was cloned into pcDNA3.1 vector, and Esat-6 gene of Mycobacterium tuberculosis was fused into downstream of the H5 gene as a genetic adjuvant for DNA vaccine candidates. The antibody level against AIV was measured using enzyme-linked immunosorbent assay (ELISA) and haemagglutination inhibition (HI) test. Sera obtained from specific-pathogen-free chickens immunized with pcDNA3.1/H5 and pcDNA3.1/H5/Esat-6 demonstrated antibody responses as early as 2 weeks after the first immunization. Furthermore, the overall HI antibody titer in chickens immunized with pcDNA3.1/H5/Esat-6 was higher compared to the chickens immunized with pcDNA3.1/H5 (p<0.05). The results suggested that Esat-6 gene of M. tuberculosis is a potential genetic adjuvant for the development of effective H5 DNA vaccine in chickens.
    Matched MeSH terms: Vaccines, DNA/immunology*
  20. Intranasal inoculation of recombinant DNA vaccine ABA392 against haemorrhagic septicaemia disease
    Kang TL, Chelliah S, Velappan RD, Kabir N, Mohamad J, Nor Rashid N, et al.
    Lett Appl Microbiol, 2019 Nov;69(5):366-372.
    PMID: 31508837 DOI: 10.1111/lam.13215
    We evaluate the efficacy of recombinant DNA vaccine ABA392 against haemorrhagic septicaemia infection through intranasal administration route by targeting the mucosal immunity. The DNA vaccine was constructed and subjected to animal study using the Sprague Dawley (SD) rat. The study was divided into two major parts: (i) active and (ii) passive immunization studies, involving 30 animals for each part. Each group was then divided into five test groups: two test samples G1 and G2 with 50 and 100 µg ml-1 purified DNA vaccine; one positive control G5 with 106  CFU per ml formalin-killed PMB2; and two negative controls, G3 and G4 with normal saline and pVAX1 vector. Both studies were conducted for the determination of immunogenicity by total white blood cell count (TWBC), indirect ELISA and histopathological changes for the presence of the bronchus-associated lymphoid tissue (BALT). Our findings demonstrate that TWBC, IgA and IgG increased after each of the three vaccination regimes: groups G1, G2 and G5. Test samples G1 and G2 showed significant differences (P DNA vaccine ABA392 can provoke mucosal immunity which makes it a potential prophylactic against HS. SIGNIFICANCE AND IMPACT OF THE STUDY: New approach of combating haemorrhagic septicaemia disease among bovines by recombinant DNA vaccine is crucial to overcome the loss of edible products from the infected bovines. DNA vaccine can potentially serve as a better immunogen which would elicit both cellular and humoral immunity, and it is also stable for its molecular reproduction. This research report demonstrates an effective yet simple way of administering the DNA vaccine via the intranasal route in rats, to provoke the mucosal immunity through the development of immunoglobulins IgA, IgG and bronchus-associated lymphoid tissue which guard as the first-line defence at the host's mucosal lining.
    Matched MeSH terms: Vaccines, DNA/immunology
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