Displaying publications 41 - 60 of 63 in total

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  1. Mahzabin T, Pillow JJ, Pinniger GJ, Bakker AJ, Noble PB, White RB, et al.
    Pediatr Res, 2017 Sep;82(3):509-517.
    PMID: 28388600 DOI: 10.1038/pr.2017.99
    BackgroundPregnant women at a high risk of preterm delivery receive glucocorticoids to accelerate fetal lung maturation and surfactant synthesis. However, the effect of antenatal steroids on the developing diaphragm remains unclear. We hypothesized that maternal betamethasone impairs the fetal diaphragm, and the magnitude of the detrimental effect increases with longer duration of exposure. We aimed to determine how different durations of fetal exposure to maternal betamethasone treatment influence the fetal diaphragm at the functional and molecular levels.MethodsDate-mated merino ewes received intramuscular injections of saline (control) or two doses of betamethasone (5.7 mg) at an interval of 24 h commencing either 2 or 14 days before delivery. Preterm lambs were killed after cesarean delivery at 121-day gestational age. In vitro contractile measurements were performed on the right hemidiaphragm, whereas molecular/cellular analyses used the left costal diaphragm.ResultsDifferent durations of fetal exposure to maternal betamethasone had no consistent effect on the protein metabolic pathway, expression of glucocorticoid receptor and its target genes, cellular oxidative status, or contractile properties of the fetal lamb diaphragm.ConclusionThese data suggest that the potential benefits of betamethasone exposure on preterm respiratory function are not compromised by impaired diaphragm function after low-dose maternal intramuscular glucocorticoid exposure.
    Matched MeSH terms: Major Histocompatibility Complex/genetics
  2. Khairuddin N, Blake SJ, Firdaus F, Steptoe RJ, Behlke MA, Hertzog PJ, et al.
    Immunol Cell Biol, 2014 Feb;92(2):156-63.
    PMID: 24217808 DOI: 10.1038/icb.2013.75
    Small interfering RNAs (siRNAs) to inhibit oncogene expression and also to activate innate immune responses via Toll-like receptor (TLR) recognition have been shown to be beneficial as anti-cancer therapy in certain cancer models. In this study, we investigated the effects of local versus systemic delivery of such immune-stimulating Dicer-substrate siRNAs (IS-DsiRNAs) on a human papillomavirus (HPV)-driven tumour model. Localized siRNA delivery using intratumour injection of siRNA was able to increase siRNA delivery to the tumour compared with intravenous (IV) delivery and potently activated innate immune responses. However, IV injection remained the more effective delivery route for reducing tumour growth. Although IS-DsiRNAs activated innate immune cells and required interferon-α (IFNα) for full effect on tumour growth, we found that potent silencing siRNA acting independently of IFNα were overall more effective at inhibiting TC-1 tumour growth. Other published work utilising IS-siRNAs have been carried out on tumour models with low levels of major histocompatibility complex (MHC)-class 1, a target of natural killer cells that are potently activated by IS-siRNA. As TC-1 cells used in our study express high levels of MHC-class I, the addition of the immunostimulatory motifs may not be as beneficial in this particular tumour model. Our data suggest that selection of siRNA profile and delivery method based on tumour environment is crucial to developing siRNA-based therapies.
    Matched MeSH terms: Histocompatibility Antigens Class I/immunology
  3. Othman S, Rahman NA, Yusof R
    Trans R Soc Trop Med Hyg, 2010 Dec;104(12):806-8.
    PMID: 20800252 DOI: 10.1016/j.trstmh.2010.07.004
    In contrast to many viruses that escape the host's immune responses by suppressing the major histocompatibility complex (MHC) class I pathway, flaviviruses have been shown to up-regulate the cell surface expression of MHC class I complex. The mechanism by which dengue virus (DV) achieves this up-regulation remains unclear. Our investigation on the HLA-A2 gene in human liver cells demonstrated that all four serotypes of dengue virus, DV1 to DV4, resulted in variable degrees of promoter induction. This illustrates the importance of MHC class I transcription regulation in primary infections by different DV serotypes that may have even greater impact in secondary infections, associated with increased disease severity.
    Matched MeSH terms: Major Histocompatibility Complex
  4. Dhaliwal JS, Shahnaz M, Too CL, Azrena A, Maiselamah L, Lee YY, et al.
    Asian Pac J Allergy Immunol, 2007 Mar;25(1):47-51.
    PMID: 17891921
    One thousand four hundreds and forty-five Malays registered with the Malaysian Marrow Donor Registry were typed for HLA-A, HLA-B and HLA-DR. Fifteen HLA-A, twenty nine HLA-B and fourteen HLA-DR alleles were detected. The most common HLA-A alleles and their frequencies were HLA-A24 (0.35), HLA-A11 (0.21) and HLA-A2 (0.15). The most common HLA-B alleles were HLA-B15 (0.26), HLA-B35 (0.11) and HLA-B18 (0.10) while the most common HLA-DR alleles were HLA-DR15 (0.28), HLA-DR12 (0.27) and HLA-DR7 (0.10). A24-B15-DR12 (0.047), A24-B15-DR15 (0.03) and the A24-B35-DR12 (0.03) were the most frequent haplotypes. This data may be useful in determining the probability of finding a matched donor and for estimating the incidence of HLA associated diseases.
    Matched MeSH terms: Histocompatibility Testing
  5. Tasnim AR, Allia S, Edinur HA, Panneerchelvam S, Zafarina Z, Norazmi MN
    Hum Immunol, 2016 Aug;77(8):618-619.
    PMID: 27296326 DOI: 10.1016/j.humimm.2016.06.009
    The earliest settlers in Peninsular Malaysia are the Orang Asli population, namely Semang, Senoi and Proto Malays. In the present study, we typed the HLA-A, -B and -DRB1 loci of the Kensiu and Semai Orang Asli sub-groups. Sequence-based HLA typing was performed on 59 individuals from two Orang Asli sub-groups. A total of 11, 18 and 14 HLA-A, -B and -DRB1 alleles were identified, respectively. These data are available in the Allele Frequencies Net Database under the population name "Malaysia Kedah Kensiu" and "Malaysia Pahang Semai".
    Matched MeSH terms: Histocompatibility Testing
  6. Koay BT, Norfarhana KF, Norhafizi MY, Lee YY, Dhaliwal JS
    Tissue Antigens, 2015 Aug;86(2):143-4.
    PMID: 26105122 DOI: 10.1111/tan.12599
    Ankylosing spondylitis (AS) is a chronic inflammatory disorder with predilection for the axial skeleton, leading to progressive restricted mobility and deformity of the spine. The fundamental mechanism involves autoimmunity orchestrated by T cells. Similar to other rheumatic diseases, the complex interplay of cytokines such as tumour necrosis factor alpha, interleukin-6 (IL 6) and interleukin-10 (IL 10) has been implicated in the pathogenesis of the disease. Despite extensive research over the past decades, the treatment options for AS, are limited. Non steroidal antiinflammatory drugs are the first line of therapy, whereas anti TNF drugs are administered for refractory cases which fail to respond to the treatment. There have been conflicting views on the correlation of IL 6 with disease activity in AS. As such, the debate on the role of anti IL6 in AS is still ongoing. Anti IL 6 such as tocilizumab and siltuximab have proven efficacy based on the large randomized controlled trials. The Food and Drug Administration (FDA) has approved these drugs for treating rheumatoid arthritis and systemic juvenile idiopathic arthritis. Researchers have adventurously experimented anti IL 6 therapy in AS but the conclusions made were not consolidated into international guidelines or consensus statement for clinical practice. In the present review, we explore the role of anti IL6 in the treatment of AS based on the cumulative evidence over recent years.
    Matched MeSH terms: Histocompatibility Testing
  7. Chan LL, Lin HP
    J Trop Pediatr, 1999 Aug;45(4):243-5.
    PMID: 10467839
    A 25-month-old boy with beta-thalassaemia major was presented with an opportunity for umbilical cord blood transplantation when his unborn sibling was diagnosed in utero to be a beta-thalassaemia carrier and also human leucocyte antigen compatible. A barely adequate amount of cord blood was collected at the birth of his sibling and infused into the patient after appropriate chemo-conditioning. Engraftment occurred without major complications. The subject is now alive and well 9 months post-transplant, thus marking our first success in umbilical cord blood transplantation.
    Matched MeSH terms: Histocompatibility Testing
  8. Dafalla AM, Edinur HA, Abdelwahed M, Elemam AA, Ibrahim AA, Mohamadani A, et al.
    Data Brief, 2019 Jun;24:104027.
    PMID: 31193964 DOI: 10.1016/j.dib.2019.104027
    Sudan is located in the heart of Africa and surrounded by eight countries with people of different ethnic origins. Historical records show that the population of the Sudan is a mixture of Arabic, West Asian Arabic and sub-Saharan African elements. The present survey provides data on allele lineages, and haplotype frequencies of Human Leukocyte Antigen (HLA) class I (HLA-A and HLA-B) and class II (HLA-DR and -HLA-DQ) loci in 11 Sudanese populations. The sampled individuals are all local transplant donors who provided informed consent for HLA analyses on their blood samples and were registered at National Cancer Institute, University of Gezira, Wad Medani. The HLA class I and II data reported here can be subjected for future analyses of genetic structure and health in Sudan. These include as reference datasets for identifying the association between HLA and diseases and for designing donor recruitment strategies.
    Matched MeSH terms: Histocompatibility Antigens Class I
  9. Kaur A, Cho L, Cereb N, Lin PY, Yang KL
    HLA, 2020 09;96(3):329-330.
    PMID: 32227684 DOI: 10.1111/tan.13884
    One nucleotide substitution in codon 73 of HLA-A*01:01:01:01 results in a novel allele, HLA-A*01:211.
    Matched MeSH terms: Histocompatibility Testing
  10. Munisvaradass R, Ding SSL, Ee AHK, Syahril Abdullah, Mok PL, Kumar S, et al.
    Sains Malaysiana, 2017;46:1831-1838.
    Breast cancer is one of the most common malignancies among woman. Decades of scientific study have linked the
    overexpression of ERBB2 antigen to aggressive tumors. To target aggressive breast cancer, chimeric antigen receptor
    (CAR) technology can be utilized. For this, human T-cells are transduced with a gene sequence encoding a CAR that is
    specific for tumor-associated antigens (TAAs). These genetically-engineered CAR transduced T-cells (CAR-T cells) are
    able to target the tumor antigen without the need for major histocompatibility complex (MHC) recognition, rendering
    it a potentially universal immunotherapeutic option. However, efficient transduction of therapeutic gene into human
    T-cells and further cell expansion are challenging. In this study, we reported a successful optimization of a transduction
    protocol using spinoculation on CD3+ T-cells with different concentrations of lentiviral plasmid encoding the CAR gene.
    CD3+T-cells were isolated from the peripheral blood mononuclear cells (PBMCs). The constructed CAR gene was inserted
    into a lentiviral plasmid containing the green fluorescent protein (GFP) tag and lentiviral particles were produced. These
    lentiviral particles were used to transduce activated T-cells by spinoculation. T-cells were activated using Dynabeadconjugated
    CD3/CD28 human T-cell activator and interleukin-2 (IL-2) before transduction. CD3+ T-cells were selected
    and GFP expression, which indicated transduction, was observed. Future studies will focus on in vitro and in vivo models
    to determine the efficiency of CAR-T cells in specifically targeting ERBB2-expressing cells.
    Matched MeSH terms: Major Histocompatibility Complex
  11. Tan HL, Zain SM, Eng HS, Mohamed Z, Mahadeva S, Chan WK, et al.
    PMID: 32410320 DOI: 10.1111/hepr.13525
    AIM: Human leukocyte antigen (HLA) regions were highlighted as important genetic markers for various liver diseases by hepatology-related genome-wide association studies. Replication studies in non-alcoholic fatty liver disease (NAFLD) are limited and none has investigated the association of HLA alleles with non-alcoholic steatohepatitis (NASH) and other histological characteristics. In the current study, we examined the association of HLA-DQA1 and HLA-DQB1 alleles with NAFLD spectrum and its histological characteristics.

    METHODS: Consecutive biopsy-proven NAFLD patients (n = 191) and healthy controls (n = 188) were enrolled and genotyped for HLA-DQA1 and HLA-DQB1 alleles using the sequence-specific oligonucleotide-polymerase chain reaction method.

    RESULTS: No association was found between the HLA alleles and NAFLD or NASH in a case-control setting. Nevertheless, among NAFLD patients, the frequency of HLA-DQB1*06 allele was significantly the lowest in NASH with significant fibrosis (10.4%) and approximately similar for NASH without significant fibrosis (22.9%) and NAFL (22.5%) (P = 0.004). It is noteworthy that the association remains significant after correction for multiple comparisons (Pc  = 0.04). Multivariate analysis revealed that HLA-DQB1*06 allele is also associated with fibrosis score (P = 0.001); the result remains significant after correction for multiple comparisons.

    CONCLUSION: These findings suggest that HLA-DQB1*06 is associated with lower fibrosis score in NAFLD patients.

    Matched MeSH terms: Histocompatibility Antigens Class I
  12. Jaganathan SK, Prasath MM
    An Acad Bras Cienc, 2018 4 12;90(1):195-204.
    PMID: 29641759 DOI: 10.1590/0001-3765201820170736
    Demand for medical implants is rising day by day as the world becomes the place for more diseased and older people. Accordingly, in this research, metallocene polyethylene (mPE), a commonly used polymer was treated with UV rays for improving its biocompatibility. Scanning electron microscopy (SEM) images confirmed the formation of crests and troughs, which depicts the improvement of surface roughness of mPE substrates caused by UV etching. Accordingly, the contact angle measurements revealed that the wettability of mPE-2.5 J/cm2 (68.09º) and mPE-5 J/cm2 (57.93º) samples were found to be increased compared to untreated mPE (86.84º) indicating better hydrophilicity. Further, the UV treated surface exhibited enhanced blood compatibility as determined in APTT (untreated mPE- 55.3 ± 2.5 s, mPE-2.5 J/cm2 - 76.7 ± 4.1 s and mPE-5 J/cm2 - 112.3 ± 2 s) and PT (untreated mPE - 24.7 ± 1.5 s, mPE- 2.5 J/cm2 - 34.3 ± 1.1 s and mPE-5 J/cm2 - 43 ± 2 s) assay. Moreover, the treated mPE-2.5 J/cm2 (4.88%) and mPE-5 J/cm2 (1.79%) showed decreased hemolytic percentage compared to untreated mPE (15.40%) indicating better safety to red blood cells. Interestingly, the changes in physicochemical properties of mPE are directly proportional to the dosage of the UV rays. UV modified mPE surfaces were found to be more compatible as identified through MTT assay, photomicrograph and SEM images of the seeded 3T3 cell population. Hence UV-modified surface of mPE may be successfully exploited for medical implants.
    Matched MeSH terms: Histocompatibility
  13. Loh SW, Ng WL, Yeo KS, Lim YY, Ea CK
    PLoS One, 2014;9(7):e103915.
    PMID: 25079219 DOI: 10.1371/journal.pone.0103915
    H3K9 methylation is one of the essential histone post-translational modifications for heterochromatin formation and transcriptional repression. Recently, several studies have demonstrated that H3K9 methylation negatively regulates the type I interferon response.
    Matched MeSH terms: Histocompatibility Antigens/metabolism*
  14. Dhaliwal JS, Wong L, Kamaluddin MA, Yin LY, Murad S
    Hum Immunol, 2011 Oct;72(10):889-92.
    PMID: 21762745 DOI: 10.1016/j.humimm.2011.06.013
    The incidence of aplastic anemia is reported to be higher in Asia than elsewhere. We studied the frequency of human leukocyte antigen (HLA) DRB1 alleles in aplastic anemia patients from 2 genetically similar aboriginal groups, the Kadazan and the Dusun, and compared them with genetically matched community and hospital controls. HLA-DRB1*15 was significantly higher in the patients compared with controls (p = 0.005), confirming similar findings in Japanese and Caucasian studies. Further testing indicated a significantly higher frequency of HLA-DRB1*1501 in patients compared with controls (p = 0.0004) but no significant difference in the frequency of HLA-DRB1*1502. The high frequency of HLA-DRB1*15 in the Kadazan and Dusun population combined with the wide variety of environmental factors associated with aplastic anemia could be the reason for the elevated incidence of aplastic anemia in the Kadazan and Dusun in Sabah.
    Matched MeSH terms: Histocompatibility Testing/methods
  15. Wen WX, Soo JS, Kwan PY, Hong E, Khang TF, Mariapun S, et al.
    Breast Cancer Res, 2016 05 27;18(1):56.
    PMID: 27233495 DOI: 10.1186/s13058-016-0717-1
    BACKGROUND: APOBEC3B is a cytosine deaminase implicated in immune response to viral infection, cancer predisposition and carcinogenesis. Germline APOBEC3B deletion is more common in East Asian women and confers a modest risk to breast cancer in both East Asian and Caucasian women. Analysis of tumour samples from women of European descent has shown that germline APOBEC3B deletion is associated with an increased propensity to develop somatic mutations and with an enrichment for immune response-related gene sets. However, this has not been examined in Asian tumour samples, where population differences in genetic and dietary factors may have an impact on the immune system.

    METHODS: In this study, we determined the prevalence of germline APOBEC3B deletion and its association with breast cancer risk in a cross-sectional hospital-based Asian multi-ethnic cohort of 1451 cases and 1442 controls from Malaysia. We compared gene expression profiles of breast cancers arising from APOBEC3B deletion carriers and non-carriers using microarray analyses. Finally, we characterised the overall abundance of tumour-infiltrating immune cells in breast cancers from TCGA and METABRIC using ESTIMATE and relative frequency of 22 immune cell subsets in breast cancers from METABRIC using CIBERSORT.

    RESULTS: The minor allelic frequency of APOBEC3B deletion was estimated to be 0.35, 0.42 and 0.16 in female populations of Chinese, Malay and Indian descent, respectively, and that germline APOBEC3B deletion was associated with breast cancer risk with odds ratios of 1.23 (95 % CI: [1.05, 1.44]) for one-copy deletion and 1.38 (95 % CI: [1.10, 1.74]) for two-copy deletion compared to women with no deletion. Germline APOBEC3B deletion was not associated with any clinicopathologic features or the expression of any APOBEC family members but was associated with immune response-related gene sets (FDR q values 

    Matched MeSH terms: Minor Histocompatibility Antigens/genetics*
  16. Stear A, Ali AOA, Brujeni GN, Buitkamp J, Donskow-Łysoniewska K, Fairlie-Clarke K, et al.
    Int J Parasitol, 2019 09;49(10):797-804.
    PMID: 31306661 DOI: 10.1016/j.ijpara.2019.05.003
    Lambs with the Major Histocompatibility Complex DRB1*1101 allele have been shown to produce fewer nematode eggs following natural and deliberate infection. These sheep also possess fewer adult Teladorsagia circumcincta than sheep with alternative alleles at the DRB1 locus. However, it is unclear if this allele is responsible for the reduced egg counts or merely acts as a marker for a linked gene. This study defined the MHC haplotypes in a population of naturally infected Scottish Blackface sheep by PCR amplification and sequencing, and examined the associations between MHC haplotypes and faecal egg counts by generalised linear mixed modelling. The DRB1*1101 allele occurred predominately on one haplotype and a comparison of haplotypes indicated that the causal mutation or mutations occurred in or around this locus. Additional comparisons with another resistant haplotype indicated that mutations in or around the DQB2*GU191460 allele were also responsible for resistance to nematode infections. Further analyses identified six amino acid substitutions in the antigen binding site of DRB1*1101 that were significantly associated with reductions in the numbers of adult T. circumcincta.
    Matched MeSH terms: Histocompatibility Antigens Class II/chemistry*
  17. Jalalonmuhali M, Ng KP, Mohd Shariff NH, Lee YW, Wong AH, Gan CC, et al.
    Transplant Proc, 2020 05 21;52(6):1718-1722.
    PMID: 32448671 DOI: 10.1016/j.transproceed.2020.02.140
    The shortage of deceased donors led to an increase of living related renal transplant performed in the presence of donor-specific antibodies (DSAs) or ABO incompatibilities. There are various desensitization protocols that have been proposed. Here, we describe the outcome of these sensitized patients. This is a prospective cohort study recruiting all kidney transplant recipients from August 2016 until June 2018. Deceased donations, ABO incompatible patients, and sensitized patients who were not prescribed on our desensitization protocol were excluded. Recipients were screened for the presence of HLA-antibodies 1 month before transplant. Those with positive DSA will undergo flow cytometry (risk stratification). We are using a protocol that consisted of intravenous rituximab 200 mg (day -14), intravenous antithymocyte globulin 5mg/kg (day 0-4), plasma exchange post transplant for patients with mean fluorescent intensity (MFI) < 3000, and negative flow cytometry. Those patients with MFI ≥ 3000 or positive flow cytometry need extra cycles pretransplant. A total of 40 patients were recruited, and 20 were sensitized patients. Among the sensitized group 4 of 20 had flow cytometry crossmatch positive, while all had preformed HLA-DSA. A total of 8 of 20 had class I HLA-DSA, 11 of 20 had class II HLA-DSA, and 1of 20 was positive for both class I and II HLA-DSA. Mean immunodominant MFI was 2133.4 (standard deviation [SD], 4451.24) and 1383.7 (SD, 2979.02) for class I and class II, respectively. At 1 year, mean serum creatinine was 108.90 (SD, 25.95) and 118.42 (SD, 31.68) in sensitized and unsensitized patients, respectively. One of 20 unsensitized patients had Banff 1B rejection at 3 months, and there was no significant rejection in sensitized patients at 6 months and 1 year. There was no difference in the occurrence of de novo HLA-DSA between the groups. Desensitization protocols may help to overcome incompatibility barriers in living donor renal transplant. The combination of low-dose rituximab, antithymocyte globulin, and judicious use of plasma exchange has worked well for our cohort.
    Matched MeSH terms: Histocompatibility Testing/methods
  18. Guerra GR, Kong JC, Millen RM, Read M, Liu DS, Roth S, et al.
    Cell Death Dis, 2021 Oct 18;12(11):959.
    PMID: 34663790 DOI: 10.1038/s41419-021-04141-5
    Anal cancer is a rare disease that has doubled in incidence over the last four decades. Current treatment and survival of patients with this disease has not changed substantially over this period of time, due, in part, to a paucity of preclinical models to assess new therapeutic options. To address this hiatus, we set-out to establish, validate and characterise a panel of human anal squamous cell carcinoma (ASCC) cell lines by employing an explant technique using fresh human ASCC tumour tissue. The panel of five human ASCC cell lines were validated to confirm their origin, squamous features and tumourigenicity, followed by molecular and genomic (whole-exome sequencing) characterisation. This panel recapitulates the genetic and molecular characteristics previously described in ASCC including phosphoinositide-3-kinase (PI3K) mutations in three of the human papillomavirus (HPV) positive lines and TP53 mutations in the HPV negative line. The cell lines demonstrate the ability to form tumouroids and retain their tumourigenic potential upon xenotransplantation, with varied inducible expression of major histocompatibility complex class I (MHC class I) and Programmed cell death ligand 1 (PD-L1). We observed differential responses to standard chemotherapy, radiotherapy and a PI3K specific molecular targeted agent in vitro, which correlated with the clinical response of the patient tumours from which they were derived. We anticipate this novel panel of human ASCC cell lines will form a valuable resource for future studies into the biology and therapeutics of this rare disease.
    Matched MeSH terms: Histocompatibility Antigens Class I/metabolism
  19. Too CL, Tan LK, Heselynn H, Nor-Shuhaila S, Eashwary M, Wahinuddin S, et al.
    Hum Immunol, 2019 Nov;80(11):906-907.
    PMID: 31558331 DOI: 10.1016/j.humimm.2019.09.005
    A total of 194 Southeast Asia Chinese from Peninsular Malaysia were genotyped for HLA-A, -B, -C -DRB1, and -DQB1 loci using polymerase chain reaction sequence-specific oligonucleotide probe hybridization methods. In this report, the HLA-B, HLA-DRB1 and HLA-DQB1 were in Hardy-Weinberg proportions (HWEP) (p > 0.05). We observed significant deviation from HWEP in HLA-A (p 
    Matched MeSH terms: Histocompatibility Testing
  20. Mohamad A, Zamri-Saad M, Amal MNA, Al-Saari N, Monir MS, Chin YK, et al.
    Vaccines (Basel), 2021 Apr 10;9(4).
    PMID: 33920311 DOI: 10.3390/vaccines9040368
    Multiple infections of several bacterial species are often observed under natural farm conditions. The infections would cause a much more significant loss compared to a single infectious agent. Vaccination is an essential strategy to prevent diseases in aquaculture, and oral vaccination has been proposed as a promising technique since it requires no handling of the fish and is easy to perform. This research attempts to develop and evaluate a potential feed-based polyvalent vaccine that can be used to treat multiple infections by Vibrios spp., Streptococcus agalactiae, and Aeromonas hydrophila, simultaneously. The oral polyvalent vaccine was prepared by mixing formalin-killed vaccine of V. harveyi, S. agalactiae, and A. hydrophila strains with commercial feed pellet, and palm oil as an adjuvant was added to improve their antigenicity. Thereafter, a vaccinated feed pellet was tested for feed quality analysis in terms of feed stability in water, proximate nutrient analysis, and palatability, safety, and growth performance using Asian seabass, Lates calcarifer as a fish host model. For immune response analysis, a total of 300 Asian seabass juveniles (15.8 ± 2.6 g) were divided into two groups in triplicate. Fish of group 1 were not vaccinated, while group 2 was vaccinated with the feed-based polyvalent vaccine. Vaccinations were carried out on days 0 and 14 with oral administration of the feed containing the bacterin at 5% body weight. Samples of serum for antibody and lysozyme study and the spleen and gut for gene expression analysis were collected at 7-day intervals for 6 weeks. Its efficacy in protecting fish was evaluated in aquarium challenge. Following vaccination by the polyvalent feed-based vaccine, IgM antibody levels showed a significant (p < 0.05) increase in serum against Vibrio harveyi, Aeromonas hydrophila, and Streptococcus agalactiae and reached the peak at week 3, 5, and 6, respectively. The high-stimulated antibody in the serum remained significantly higher than the control (p < 0.05) at the end of the 6 weeks vaccination trial. Not only that, but the serum lysozyme level was also increased significantly at week 4 (p < 0.05) as compared to the control treatment. The immune-related gene, dendritic cells, C3, Chemokine ligand 4 (CCL4), and major histocompatibility complex class I (MHC I) showed significantly higher expression (p < 0.05) after the fish were vaccinated with the oral vaccine. In the aquarium challenge, the vaccine provided a relative percentage survival of 75 ± 7.1%, 80 ± 0.0%, and 80 ± 0.0% after challenge with V. harveyi, A. hydrophila, and S. agalactiae, respectively. Combining our results demonstrate that the feed-based polyvalent vaccine could elicit significant innate and adaptive immunological responses, and this offers an opportunity for a comprehensive immunization against vibriosis, streptococcosis, and motile aeromonad septicemia in Asian seabass, Lates calcarifer. Nevertheless, this newly developed feed-based polyvalent vaccination can be a promising technique for effective and large-scale fish immunization in the aquaculture industry shortly.
    Matched MeSH terms: Major Histocompatibility Complex
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