• IMMUNE NETWORK
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• v.5 no.3
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• pp.150-156
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• 2005

Background: Dendritic cells (DCs) playa critical role not only in the initiation of immune responses, but also in the induction of immune tolerance. In an effort to regulate immune responses through the modulation of antigen presenting cell (APC) function of DCs, we searched for and characterized APC function modulators from natural products. Methods: DCs were cultured in the presence of propolis components, WP and CP, and then examined for their ability to present exogenous antigen in association with major histocompatibility complexes (MHC). Results: WP and CP inhibited class I MHC-restricted presentation of exogenous antigen (cross-presentation) in a DC cell line, DC2.4 cells, and DCs generated from bone marrow cells with GM-CSF and IL-4. The inhibitory activity of WP and CP appeared to be due not only to inhibition of phagocytic activity of DCs, but also to suppression of expression of MHC molecules on DCs. We also examined the effects of WP and CP on T cells. Interestingly, WP and CP increased IL-2 production from T cells. Conclusion: These results demonstrate that WP and CP inhibit MHC-restricted presentation of exogenous antigen through down-regulation of phagocytic activity and suppression of expression of MHC molecules on DCs.

• IMMUNE NETWORK
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• v.4 no.4
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• pp.205-215
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• 2004

In the early host defense system, effector function of natural killer (NK) cells results in natural killing against target cells such as microbe-infected, malignant, and certain allogenic cells without prior stimulation. NK cell cytotoxicity is selectively regulated by homeostatic prevalence between a repertoire of both activating and inhibitory receptors, and the discrimination of untransformed cells is achieved by recognition of major histocompatibility complex (MHC) class I alleles through inhibitory signals. Although it is well known that the bipotential T/NK progenitors are derived from the common precusor, functional mechanisms in terms of the development of NK cells remain to be further investigated. NK cells are mainly involved in innate immunity, but recent studies have been reported that they also play a critical role in adaptive immune responses through interaction with dendritic cells (DC). This interaction will provide effector functions and development of NK cells, and elucidation of its precise mechanism may lead to therapeutic strategies for effective treatment of several immune diseases.

• Fisheries and Aquatic Sciences
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• v.27 no.3
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• pp.159-170
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• 2024

Research to obtain molecular markers related to the major histocompatibility complex (MHC) gene in both strains of gourami is essential to increase the success of the selection program of disease resistance traits. Using a completely randomized design (CRD), the challenge test consists of four treatments and seven replications. The treatment was Jambi gourami injected with PBS (KJ), Kalimantan gourami injected with PBS (KK), Jambi strain injected with Aeromonas hydrophila (GJ), and Kalimantan strain injected with A. hydrophila (GK). The GJ population was more resistant to A. hydrophila than the GK population. The MHC II gene was detected in both test strains (GJ and GK), both resistant and susceptible fish. However, there were differences in the results of amplifying the MHC II gene in susceptible and resistant fish. Two DNA fragments approximately 400 and 585 bp were detected in the genome of susceptible fish, while in the genome of susceptible fish, only one DNA fragment was detected (400 bp). Therefore, the MHC II gene fragment with a size of about 585 bp can be used as a potential candidate for specific molecular markers to obtain resistance to A. hydrophila bacteria in the giant gourami.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.11
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• pp.1487-1494
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• 2009

The major histocompatibility complex (MHC) plays well-defined roles in eliciting immune responses and combating infectious diseases. The major histocompatibility complex of cattle is referred to as BoLA (Bovine Lymphocyte Antigen). This genetic system is among the most polymorphic. In the present study, polymorphism of the BoLA- DRB3.2 locus in three Bos indicus breeds viz., Sahiwal, Rathi and Hariana was studied by polymerase chain reaction restriction fragment length polymorphism technique using the enzymes RsaI, Bst Y1 and Hae III. Both Sahiwal and Rathi are good Indian dairy breeds and survive under tough tropical conditions, while Hariana is a prominent dual-purpose breed reared both as a dairy animal and for bullock production. A total of 30 different BoLADRB3.2 alleles were observed to be present in the 3 Bos indicus breeds. Certain alleles were common amongst the three breeds while there were others that were unique to each breed. Allelic distribution amongst the three breeds showed that each breed had a unique allelic distribution pattern that was different from each other and also different from the earlier breeds studied so far for the existence of allelic variation at this locus. A dendogram was constructed based on the frequencies of the BoLA-DRB3 alleles using the UPGMA method. The Rathi and Hariana animals were genetically the most apart. The Hariana animals clustered on a different branch from the other two breeds viz. the Rathi and the Sahiwal. The smallest genetic distances for the DRB3 alleles were those between Sahiwal and Rathi (0.5461) while genetic distance between Hariana and Sahiwal was 0.6123. A comparison of the allelic frequencies of the BoLADRB3.2 locus in these 3 breeds viz. Sahiwal, Hariana and Rathi with the allelic frequencies present in the previously characterized Bos indicus Kankrej breed, which is a dual purpose breed reared both as a draught and a dairy animal, showed that the Bos indicus Sahiwal and Rathi breeds clustered into one group while the Hariana and Kankrej breeds formed another group. The Rathi and Sahiwal showed the least genetic distance of 0.5461 amongst the breeds whereas the Rathi and Kankrej, with a Nei''s genetic distance of 1.1622, were genetically the most distant apart.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.5
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• pp.614-628
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• 2019

Objective: The inhibitory leukocyte immunoglobulin-like receptors (LILRBs) play an important role in innate immunity. The present study represents the first description of the cloning and structural and functional analysis of LILRB1 and LILRB3 isolated from two genetically disparate chicken lines. Methods: Chicken LILRB1-3 genes were identified by bioinformatics approach. Expression studies were performed by transfection, quantitative polymerase chain reaction. Signal transduction was analyzed by western blots, immunoprecipitation and flow cytometric. Cytokine levels were determined by enzyme-linked immunosorbent assay. Results: Amino acid homology and phylogenetic analyses showed that the homologies of LILRB1 and LILRB3 in the chicken line 6.3 to those proteins in the chicken line 7.2 ranged between 97%-99%, while homologies between chicken and mammal proteins ranged between 13%-19%, and 13%-69%, respectively. Our findings indicate that LILRB1 and LILRB3 subdivided into two groups based on the immunoreceptor tyrosine-based inhibitory motifs (ITIM) present in the transmembrane domain. Chicken line 6.3 has two ITIM motifs of the sequence LxYxxL and SxYxxV while line 7.2 has two ITIM motifs of the sequences LxYxxL and LxYxxV. These motifs bind to SHP-2 (protein tyrosine phosphatase, non-receptor type 11) that plays a regulatory role in immune functions. Moreover, our data indicate that LILRB1 and LILRB3 associated with and activated major histocompatibility complex (MHC) class I and ${\beta}2-microglobulin$ and induced the expression of transporters associated with antigen processing, which are essential for MHC class I antigen presentation. This suggests that LILRB1 and LILRB3 are transcriptional regulators, modulating the expression of components in the MHC class I pathway and thereby regulating immune responses. Furthermore, LILRB1 and LILRB3 activated Janus kinase2/tyrosine kinase 2 (JAK2/TYK2); signal transducer and activator of transcription1/3 (STAT1/3), and suppressor of cytokine signaling 1 genes expressed in Macrophage (HD11) cells, which induced Th1, Th2, and Th17 cytokines. Conclusion: These data indicate that LILRB1 and LILRB3 are innate immune receptors associated with SHP-2, MHC class I, ${\beta}2-microglobulin$, and they activate the Janus kinase/signal transducer and activator of transcription signaling pathway. Thus, our study provides novel insights into the regulation of immunity and immunopathology.

• Clinical and Experimental Vaccine Research
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• v.11 no.3
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• pp.249-263
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• 2022

Purpose: Lassa fever is a zoonotic acute viral hemorrhagic disease caused by Lassa virus (LASV). There is currently no licensed vaccine for the prevention of the disease. This study is aimed at discovering immunodominant epitopes from the envelope glycoprotein of the Lassa mammarenavirus and designing of a multi-epitope vaccine candidate (VC). Materials and Methods: The amino acid sequences of the envelope glycoprotein of 26 strains of LASV from five countries were selected. After evaluation for antigenicity, immunogenicity, allergenicity, and toxicity, immunodominant CD8, CD4, and linear B lymphocytes were also selected. The selected epitopes were modelled and a molecular docking with the appropriate major histocompatibility complex (MHC) proteins was performed. Using an adjuvant and linkers, a multi-epitope VC was designed. The VC was evaluated for its physicochemical and immunological properties and structurally refined, validated, and mutated (disulphide engineering). The complex formed by the VC and the toll-like receptor-4 receptor was subjected to molecular dynamic simulation (MDS) followed by in silico cloning in a plasmid vector. Results: A VC with 203 sequences, 22.13 kDa weight, isoelectric point of 9.85 (basic), instability index value of 27.62, aliphatic index of 68.87, and GRAVY value of -0.455 (hydrophilic) emerged. The VC is predicted to be non-allergenic with antigenicity, MHC I immunogenicity, and solubility upon overexpression values of 0.81, 2.04, and 0.86 respectively. The VC also has an estimated half-life greater than 10 hours in Escherichia coli and showed stability in all the parameters of MDS. Conclusion: The VC shows good promise in the prevention of Lassa fever but further tests are required to validate its safety and efficacy.

• IMMUNE NETWORK
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• v.9 no.6
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• pp.285-288
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• 2009

The expression pattern of immunoproteasomes in human thymus has not been analyzed but may have important consequences during thymic selection. Here we examined the expression patterns of immunoproteasome subunits in fetal and adult thymic tissues by immunohistochemistry and found that all three subunits are expressed in both cortical and medullary stromal cells. These data suggest that thymic selection in human can be affected by peptide repertoires generated by immunoproteasomes.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.215-216
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• 2001

Mouse monoclonal antibody(mAb) with an antigen specificity for major histocompatibility complex class Il(MHC class II) was produced and secreted from tobacco cell suspension culture by successive sexual crossesu. Expression and secretion of assembled antibody was observed in transgenic tobacco cell suspension culture by wetern blot analysis.

• Genomics & Informatics
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• v.15 no.3
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• pp.108-111
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• 2017

Recently developed computational methods allow the imputation of human leukocyte antigen (HLA) genes using intergenic single nucleotide polymorphism markers. To improve the imputation accuracy in HLA imputation, it is essential to increase the sample size and the diversity of alleles in the reference panel. Our software, MergeReference, helps achieve this goal by providing a streamlined pipeline for combining multiple reference panels into one.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.3
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• pp.321-326
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• 2016

The porcine major histocompatibility complex (MHC) is called swine leukocyte antigen (SLA), which controls immune responses and transplantation reactions. The SLA is mapped on pig chromosome 7 (SSC7) near the centromere. In this study, 3 class I (SLA-1, SLA-3, and SLA-2) and 3 class II (DRB1, DQB1, and DQA) genes were used for investigation of SLA haplotypes in Yucatan miniature pigs in Korea. This pig breed is a well-known model organism for biomedical research worldwide. The current study indicated that Korean Yucatan pig population had 3 Class I haplotypes (Lr-4.0, Lr-6.0, and Lr-25.0) and 3 class II haplotypes (Lr-0.5, Lr-0.7, and Lr-0.25). The combinations of SLA class I and II haplotype together, 2 homozygous (Lr-4.5/4.5 and Lr-6.7/6.7) and 3 heterozygous (Lr-4.5/6.7, Lr-4.5/25.25, and Lr-6.7/25.25) haplotypes were identified, including previously unidentified new heterozygous haplotypes (Lr-4.5/4.7). In addition, a new SLA allele typing method using Agilent 2100 bioanalyzer was developed that permitted more rapid identification of SLA haplotypes. These results will facilitate the breeding of SLA homozygous Yucatan pigs and will expedite the possible use of these pigs for the biomedical research, especially xenotransplantation research.