• Molecules and Cells
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• 제44권5호
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• pp.310-317
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• 2021

Cluster of differentiation 1 (CD1) is a family of cell-surface glycoproteins that present lipid antigens to T cells. Humans have five CD1 isoforms. CD1a is distinguished by the small volume of its antigen-binding groove and its stunted A' pocket, its high and exclusive expression on Langerhans cells, and its localization in the early endosomal and recycling intracellular trafficking compartments. Its ligands originate from self or foreign sources. There are three modes by which the T-cell receptors of CD1a-restricted T cells interact with the CD1a:lipid complex: they bind to both the CD1a surface and the antigen or to only CD1a itself, which activates the T cell, or they are unable to bind because of bulky motifs protruding from the antigen-binding groove, which might inhibit autoreactive T-cell activation. Recently, several studies have shown that by producing T_H2 or T_H17 cytokines, CD1a-restricted T cells contribute to inflammatory skin disorders, including atopic dermatitis, psoriasis, allergic contact dermatitis, and wasp/bee venom allergy. They may also participate in other diseases, including pulmonary disorders and cancer, because CD1a-expressing dendritic cells are also located in non-skin tissues. In this mini-review, we discuss the current knowledge regarding the biology of CD1a-reactive T cells and their potential roles in disease.

• BMB Reports
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• 제28권4호
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• pp.353-358
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• 1995

Epitope tagging is the process of fusing a set of amino acid residues that are recognized as an antigenic determinant to a protein of interest. Tagging a protein with an epitope facilitates various immunochemical analyses of the tagged protein with a specific monoclonal antibody. The monoclonal antibody H8 has subtype specificity for an epitope derived from the preS2 region of hepatitis B virus surface antigen. Previous studies on serial deletions of the preS2 region indicated that the preS2 epitope was located in amino acid residues 130~142. To test whether the amino acid sequence in this interval is sufficient to confer on proteins the antigenicity recognizable by the antibody H8, the set of amino acid residues in the interval was tagged to the amino terminal of ${\beta}$-galactosidase and to the carboxyl terminal of the truncated $p56^{lck}$ fragment. The tagged ${\beta}$-galactosidase, expressed in Escherichia coli, maintained the enzymatic activity and was immunoprecipitated efficiently with H8. The tagged $p56^{lck}$ fragment, synthesized in an in vitro translation system, was also immunoprecipitated specifically with H8. These results demonstrate that the amino acid sequence of the preS2 region can be used efficiently for the epitope tagging approach.

• 대한미생물학회지
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• 제17권1호
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• pp.1-6
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• 1982

To investigate the annual distribution of hepatitis B surface antigen(HBs Ag) in healthy adults, this study was performed by means of counter-immunoelectrophoresis with sera obtained from 4,856 healthy adults who reside in Seoul and Gyunggi-Do area from January to December, 1981. The experimental procedures were same with the previous reports. The subjectives were consisted of two groups: one is mass life group(3.853 adults) and the other, home life group(1.003 adults). The results were as follows: 1. Among the 4.856 cases tested, 326 cases(6.71%) showed HBs Ag positive. HBs Ag positive rates in the group of mass life and home life were 6.51% and 7.48%, respectively. 2. It showed slightly high positive rates in the home life and long term duration group, and upper class group showed slightly high positive rate. 3. In seasonal variation, it showed relatively high positive rate(7.38%) in winter, and A blood group showed higher rate(7.60%) than the other blood groups. And then, boundary area of Seoul city showed slightly high positive rate(7.36%) in areal distribution.

• 대한바이러스학회지
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• 제27권2호
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• pp.137-141
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• 1997

We evaluated Immunochromatographic assay kit to screen HBsAg in human serum. When the reference HBsAg was applyed to ICA, HA and EIA kits, the limit of detection for HBsAg were found out to be 4, 2 and 0.25 ng/ml respectively. But ICA kit required 5 minutes to read the result whereas HA and EIA kit more than one hour. The sensitivity was 97% (29 of 30 samples) and the specificity 100% (45 samples) compared with conventional EIA. The ICA kit needs no instrument or machine to perform the test contrary to the conventional methods. Therefore, this rapid and sensitive ICA kit can be used for HBsAg-screening, especially in the emergency room and in the scene of the accident.

• Molecules and Cells
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• 제22권2호
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• pp.175-181
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• 2006

Delivery of DNA vaccines to airway mucosa would be an ideal method for mucosal immunization. However, there have been few reports of a suitable gene delivery system. In this study we used a cationic emulsion to immunize mice via the intranasal route with pCMV-S coding for Hepatitis B virus surface antigen (HBsAg). Complexing pCMV-S with a cationic emulsion dramatically enhanced HBsAg expression in both nasal tissue and lung, and was associated with increases in the levels of HBs-specific Abs in serum and mucosal fluids, of cytotoxic T lymphocytes (CTL) in the spleen and cervical and iliac lymph nodes, and of delayed-type hypersensitivity (DTH) against HBsAg. In contrast, very weak humoral and cellular immunities were observed following immunization with naked DNA. In support of these observations, a higher proliferative response of spleenocytes was detected in the group immunized with the emulsion/pCMV-S complex than in the group immunized with naked pCMV-S. These findings may facilitate development of an emulsion-mediated gene vaccination technique for use against intracellular pathogens that invade mucosal surfaces.

• 농촌의학ㆍ지역보건
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• 제17권2호
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• pp.129-136
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• 1992

To evaluate the possible route of intrafamilial transmission among carriers of hepatitis B surface antigen ($HB_sAg$), epidemiologic and serologic data were obtained on 107 household contacts of 35 carriers of HBsAg and on 71 household contacts of 25 controls who were negative for serologic markers of hepatitis B virus. The HBsAg prevalence was 26.5% among the contacts of carriers compared to 0.0% among the contacts of controls. And the combined prevalence for all hepatitis markers was 48.5% among the contacts of carriers compared to 26.0% among the contacts of controls(p<0.05). Especially the offspring of carriers showed significantly higher risk in the combined prevalence for all hepatitis markers (p<0.05). There were no significant relationship between HBV infection and past history like acupuncture, transfusion, operation and tattooed. Factors associated with the risk of intrafamilial transmission of HBV were not found in the sharing of household articles such as razor, towel, drinking glass, nail clippers, toothbrush and tableware.

• 생명과학회지
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• 제15권6호
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• pp.1034-1036
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• 2005

배추 종자 및 유묘에 대하여 GUS발현 또는 hepatitis B surface antigen (HBsAg)발현 벡터를 지니는 Agrobacterium tumefaciens LBA4404 세포를 이용하여 진공침윤(agroinfiltration)에 의한 형질전환을 시도하였다. 특히 ELISA를 이용한 HBsAg발현의 정량적 분석에서 agroinfiltration방법은 형질전환효율이 매우 저조하게 나타났다. 그러나 차아염소산나트륨 용액을 발아 전 또는 발아 중인 배추종자에 처리한 후 agroinfiltration을 실시한 경우 형질전환 효율이 $2\~5$배 증가하였다. 따라서 차아염소산나트륨 등의 화학연마제에 의한 종자의 상처발생이 Agrobacterium의 감염을 용이하게 함으로써 배추유묘에서의 일시유전자발현을 증대시키는 것으로 제안되고있다.

• Asian-Australasian Journal of Animal Sciences
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• 제18권12호
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• pp.1691-1695
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• 2005

The bovine lymphocyte antigen (BoLA)-DRB3 gene encodes cell surface glycoproteins that initiate immune responses by presenting processed antigenic peptides to CD4 T helper cells. DRB3 is the most polymorphic bovine MHC class II gene which encodes the peptide-binding groove. Since different alleles favour the binding of different peptides, DRB3 has been extensively evaluated as a candidate marker for associations with various bovine diseases and immunological traits. For that reason, the genetic diversity of the bovine class II DRB3 locus was investigated by polymerase chain reaction-restriction fragment length polymorphism method (PCR-RFLP). This study describes genetic variability in the BoLA-DRB3 in Iranian Golpayegani Cattle. Iranian Golpayegani Cows (n = 50) were genotyped for bovine lymphocyte antigen (BoLA)-DRB3.2 allele by polymerase chain reaction and restriction fragment length polymorphism method. Bovine DNA was isolated from aliquots of whole blood. A two-step polymerase chain reaction followed by digestion with restriction endonucleases RsaI, HaeIII and BstYI was conducted on the DNA from Iranian Golpayegani Cattle. In the Iranian Golpayegani herd studied, we identified 19 alleles.DRB3.2${\times}$16 had the highest allelic frequency (14%), followed by DRB3.2${\times}$7 (11%). Six alleles (DRB3.2${\times}$25, ${\times}$24, ${\times}$22, ${\times}$20, ${\times}$15, ${\times}$3) had frequencies = 2%. Although additional studies are required to confirm the present findings, our results indicate that exon 2 of the BoLA-DRB3 gene is highly polymorphic in Iranian Golpayegani Cattle.

• Journal of Microbiology and Biotechnology
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• 제28권1호
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• pp.122-135
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• 2018

Listeriolysin O (LLO), one of the most immunogenic proteins of Listeria monocytogenes and its main virulence factor, mediates bacterial escape from the phagosome of the infected cell. Thus, its expression in a nonpathogenic bacterial host may enable effective delivery of heterologous antigens to the host cell cytosol and lead to their processing predominantly through the cytosolic MHC class I presentation pathway. The aim of this project was to characterize the delivery of a model antigen, chicken egg ovalbumin (OVA), to the cytosol of dendritic cells by recombinant Bacillus subtilis vegetative cells expressing LLO. Our work indicated that LLO produced by non-sporulating vegetative bacteria was able to support OVA epitope presentation by MHC I molecules on the surface of antigen presenting cells and consequently influence OVA-specific cytotoxic T cell activation. Additionally, it was proven that the genetic context of the epitope sequence is of great importance, as only the native full-sequence OVA fused to the N-terminal fragment of LLO was sufficient for effective epitope delivery and activation of $CD8^+$ lymphocytes. These results demonstrate the necessity for further verification of the fusion antigen potency of enhancing the MHC I presentation, and they prove that LLO-producing B. subtilis may represent a novel and attractive candidate for a vaccine vector.

• International Journal of Oral Biology
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• 제42권2호
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• pp.63-70
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• 2017

Selecting an appropriate antigen with optimal immunogenicity and physicochemical properties is a pivotal factor to develop a protein based subunit vaccine. Despite rapid progress in modern molecular cloning and recombinant protein technology, there remains a huge challenge for purifying and using protein antigens rich in hydrophobic domains, such as membrane associated proteins. To overcome current limitations using hydrophobic proteins as vaccine antigens, we adopted in silico analyses which included bioinformatic prediction and sequence-based protein 3D structure modeling, to develop a novel periodontitis subunit vaccine against the outer membrane protein FomA of Fusobacterium nucleatum. To generate an optimal antigen candidate, we predicted hydrophilicity and B cell epitope parameter by querying to web-based databases, and designed a truncated FomA (tFomA) candidate with better solubility and preserved B cell epitopes. The truncated recombinant protein was engineered to expose epitopes on the surface through simulating amino acid sequence-based 3D folding in aqueous environment. The recombinant tFomA was further expressed and purified, and its immunological properties were evaluated. In the mice intranasal vaccination study, tFomA significantly induced antigen-specific IgG and sIgA responses in both systemic and oral-mucosal compartments, respectively. Our results testify that intelligent in silico designing of antigens provide amenable vaccine epitopes from hard-to-manufacture hydrophobic domain rich microbial antigens.