• BMB Reports
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• 제30권3호
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• pp.177-181
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• 1997

We constructed a single-chain immunoglobulin in which the carboxyl end of the heavy chain variable domain is covalently joined to the amino terminus of the light chain variable domain via peptide linker and the carboxyl end of the light chain variable domain is linked to human ${\gamma}1$ Fc region through the hinge region. The molecule was expressed in Chinese hamster ovary cells, assembled into a dimeric molecule and secreted into the culture medium. The dimeric molecule (2E11) was purified from the culture supernatant by affinity chromatography on Protein G-Sepharose column. The size of the unreduced or reduced protein was the expected molecular weight of approximately 120 or 60 kDa, respectively, as assessed by SDS-polyacrylamide gel electrophoresis. The antigen-binding affinity of 2E11 was almost the same as that of a native antibody counterpart (CS131A), suggesting that the single-chain immunoglobulin may function like a native antibody.

• Journal of Animal Science and Technology
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• 제50권1호
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• pp.9-18
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• 2008

본 연구에서는 조류에서 종 특이적인 DNA 염기서열변이를 검증하기 위하여 닭, 꿩, 칠면조, 메추리의 immunoglobulin light chain constant domain 유전자를 클로닝하여 DNA염기서열을 분석하였다. 종간에 구별이 가능한 DNA 염기서열변이가 위의 유전자에서 관찰되었다. PCR을 이용하여 종을 구별하기 위하여 종 사이에 특이적인 DNA 염기서열 부위에 한 쌍의 종 특이적인 프라이머를 제작하였다. 또한 비교실험을 위하여 이미 알려진 cytochrome b와 tapasin 유전자에서도 두 쌍의 종 특이적 프라이머를 제작하였다. PCR결과 세 쌍의 프라이머 모두 종 특이적으로 DNA를 증폭하였다. Immunoglobulin 유전자의 염기서열 변이를 이용한 종 특이적인 PCR 방법은 조류의 유전자원 보존을 위한 이종간 카이메라 연구에 유용하게 이용될 수 있을 것이다.

• IMMUNE NETWORK
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• 제3권3호
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• pp.227-234
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• 2003

Background: Immunoglobulin (Ig) light chain repertoire has been implicated as a critical determinant in regulation of autoreactive B cells and production of pathogenic anti-DNA antibodies in systemic lupus erythematosus (SLE). We analyzed the impact of Ig ${\lambda}$ chain repertoire on development of autoimmunity in patients with SLE. Methods: We obtained genomic DNA from individual peripheral CD19+ B cells of 3 untreated active SLE patients, and amplified $V{\lambda}$ rearrangements from each single cell by polymerase chain reaction. Results: A total number of 208 $V{\lambda}J{\lambda}$ rearrangements were analyzed. Analyzed sequences included 158 productive rearrangements and 50 nonproductive rearrangements. The differences in $V{\lambda}$ gene usage in the productive and nonproductive repertoire of SLE patients were found compared to the non-autoimmune individuals. $V{\lambda}$ gene, 9A was significantly overrepresented in nonproducative repertoire of SLE patients (P=0.016). In the productive repertoire, $V{\lambda}$ genes, 3L and 1E were found more often in the SLE patients (P=0.001, P=0.043). When the productive and the nonproductive repertoires were compared, 9A was found significantly less in the productive repertoire in the SLE patients (P=0.000). There were no significant differences in the $J{\lambda}$ gene usage between SLE patients and non-autoimmune individuals, but $J{\lambda}2/3$ gene was the most frequently used in SLE, whereas $J{\lambda}7$ gene was the most frequently used in the normal subjects. In the productive SLE $V{\lambda}$ repertoire, 9.4% of the total sequences employed identical CDR3. It was particularly striking to find 7 identical versions of the 1G-$J{\lambda}2/3$ $V{\lambda}J{\lambda}$ rearrangements from one patient and 3 of the same sequence from another patient. Notably, identical $V{\lambda}$ junctions in the SLE patients utilized significantly more homologous joining compared to $V{\lambda}$ junctions of the normal adults (P=0.044). Conclusion: These data demonstrate regulation of ${\lambda}$ light chain expression in the SLE patients by selection of unique $V{\lambda}$ genes. Also, biased selection and clonal expansion of particular $V{\lambda}$ rearrangements are apparent in the SLE ${\lambda}$ repertoire.

• 한국어병학회지
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• 제34권1호
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• pp.111-115
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• 2021

Immunoglobulin M (IgM) of sevenband grouper (Epinephelus septemfasciatus) was purified by mannan-binding protein (MBP) affinity column. The purified IgM had an apparent molecular weights of 76 (heavy chain) and 28 (light chain) kDa in sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Eight hybridoma clones secreting monoclonal antibodies (mAbs) against sevenband grouper IgM were established. Antibody detection enzyme-linked immunosorbent assay (ELISA) with bovine serum albumin (BSA, antigen) and the 8 mAbs revealed that optical density (OD) values were clearly different between sera from BSA-immunization and non-immunization of sevenband grouper. These results suggest that the produced mAbs in this study are specifically reacted with IgM of sevenband grouper.

• IMMUNE NETWORK
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• 제2권4호
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• pp.233-241
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• 2002

Background: Monoclonal antibodies (mAb) of rodent origin are produced with ease by hybridoma fusion technique, and have been successfully used as therapeutic reagents for humans after humanization by genetic engineering. However, utilization of these antibodies for therapeutic purpose has been limited by the fact that they act as immunogens in human body causing undesired side effects. So far, there have been several attempts to produce human mAbs for effective in vivo diagnostic or therapeutic reagents including the use of humanized xenomouse that is generated by mating knockout mice which lost Ig heavy and light chain genes by homologous recombination and transgenic mice having both human Ig heavy and light gene loci in their genome. Methods: Genomic DNA fragments of mouse Ig heavy and light chain were obtained from a mouse brain ${\lambda}$ genomic library by PCR screening and cloned into a targeting vector with ultimate goal of generating Ig knockout mouse. Results: Through PCR screening of the genomic library, three heavy chain and three light chain Ig gene fragments were identified, and restriction map of one of the heavy chain gene fragments was determined. Then heavy chain Ig gene fragments were subcloned into a targeting vector. The resulting construct was introduced into embryonic stem cells. Antibiotic selection of transfected cells is under the progress. Conclusion: Generation of xenomouse is particularly important in medical biotechnology. However, this goal is not easily achieved due to the technical difficulties as well as huge financial expenses. Although we are in the early stage of a long-term project, our results, at least, partially contribute the successful generation of humanized xenomouse in Korea.

• 한국어병학회지
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• 제17권1호
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• pp.11-20
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• 2004

Edwardsiella tarda로 면역한 닭의 난황항체 (IgY) 정제 방법을 비교하였다. Anti-E. tarda IgY의 정제는 PEG법, chloroform-PEG법, ammonium sulfate법과 정제 kit를 사용한 4가지 다른 방법으로 실시하였다. 정제된 IgY는 64 kDa의 heavy chain과 27 kDa의 light chain을 나타내었다. E. tarda로 면역된 IgY는 면역되지 않은 대조 IgY 보다 높은 ELISA가와 응집항체가를 나타내었으며, 정제된 IgY는 western blotting에서 anti-E. tarda 토끼혈청과 유사한 E.tarda 단백질을 인식하였다. PEG법과 ammonium sulfate법에 의해 정제된 IgY는 응집항체가가 1:512, chloroform-PEG법과 정제 kit에 의해 정제된 IgY는 1:128을 나타내었으며, PEG법이 IgY를 정제하기 위한 가장 빠른 방법이었다. 이 연구의 결과로 PEG법이 IgY의 생물학적 활성을 유지함과 더불어 신속하고 효과적인 정제방법임을 알 수 있었다.

• BMB Reports
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• 제37권3호
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• pp.314-319
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• 2004

Flounder (Paralichthys olivaceus) Immunoglobulins (Igs) were purified from the serum of mouse IgG-immunized flounder by using affinity chromatography. Under denaturing conditions in SDS-PAGE, the flounder Igs appeared to be composed of 2 heavy (H) chains (72 and 77 kDa) and two light (L) chains (26 and 28 kDa). Monoclonal antibodies (MAbs) were produced by the fusion of myeloma cells (SP2/0) with Balb/c mouse spleen cells that were previously sensitized against affinity-purified flounder Igs. In a Western blot analysis, the produced MAbs, FIM511, FIM519, and FIM562 recognized both the 72 and 77 kDa H chains, 26 kDa, and 28 kDa L chain, respectively. Mouse antiserum against flounder Igs reacted more strongly with the L chain of 28 kDa than with 26 kDa, suggesting that the 28 kDa molecule is more immunogenic than the 26 kDa L chain molecule. In a FACS analysis, the ratios of the Ig+ cell population in the flounder head kidney and spleen cells were 49% and 24%, respectively. Unexpectedly, however, the ratios of the Ig+ B-like cell population in the flounder were not significantly augmented, even after the immunization of an immunogenic antigen. This suggests that the humoral immune response in fish could be considerably different from that in mammals. The produced MAbs in this study would be useful in characterizing flounder Ig+ B-like cells and in developing flounder Ig detecting an immunoassay system.

• 농업과학연구
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• 제22권1호
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• pp.82-95
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• 1995

본(本) 연구(硏究)는 한국인(韓國人) 산모(産母)로 부터 수집한 초유(初乳) 및 Holstein종(種)으로 부터 수집한 초유(初乳) 중에 존재하는 Secretory immunoglobulin A의 분리방법(分離方法)을 검토하고 분리(分離)된 분획들의 면역화학적(免疫化學的) 특성을 비교 검토하여 향후 인공영양(人工營養)에 대한 시험(試驗) 자료를 얻고자 하였으며 그 결과(結果)는 다음과 같다. 1. 인유(人乳) 초유(初乳) 중의 SIgA는 Sephadex G-200과 Sepharose 6B를 통한 gel-filtration 만으로도 순수한 상태로 분리(分離) 정제할 수 있었으나, 우유(牛乳) 초유(初乳) 중의 SIgA는 gel-filtration을 반복하는 방법(方法)으로는 순수한 상태로 분리(分離) 및 정제할 수 없었으며, gel-filtration으로 얻어진 SIgA rich fraction을 모아서 DEAE를 실시한 결과(結果) 또한 마찬가지로 SIgA를 순수한 상태로 분리(分離)할 수는 없었다. 2. 인유(人乳) 초유(初乳)로 부터 gel-filtration을 통하여 분리(分離)한 분획들을 Immunoelectrophoresis 및 Double immunodiffusion 방법(方法)으로 면역화학적(免疫化學的) 특성을 살펴본 결과(結果), 첫번째 peak의 분획에서 IgM이 존재하고 있음을 확인할수 있었으며 두번째 peak의 분획에서 SIgA가 순수한 상태로 존재하고 있음을 확인할수 있었다. 반면에 우유(牛乳) 초유(初乳)로 부터 gel filtration 및 DEAE를 통하여 분리(分離)한 분획들을 같은 방법(方法)으로 면역화학적(免疫化學的) 특성을 살펴본 결과(結果), SIgA rich fraction 중에는 IgG가 다량(多量)으로 혼재(混在)되어 있음을 확인할 수 있었다. 3. 우유(牛乳) 초유(初乳)에서 분리(分離)한 SIgA rich fraction의 Fragment를 SDS-PAGE로 분자량을 측정해 본 결과(結果), Secretory component가 77,000-80,000, Heavy chain이 50,000-60,000, Light chain이 25,000-27,000 dalton으로 나타났으며 J-chain은 Light chain과 중복되어 분자량 측정이 어려웠다. 이와같은 결과(結果)는 인유(人乳) 초유(初乳) 중에 존재하는 SIgA Fragment 분자량과 유사한 결과(結果)를 보여주었다.

• 한국해양바이오학회지
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• 제1권3호
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• pp.218-223
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• 2006

어류의 세균성질병 원인체인 Edwardsiella tarda 감염의 예방과 치료에 E. tarda로 면역한 계란으로부터 얻어진 난황항체 (IgY)의 잠정적인 사용을 평가하였다. PEG법으로 정제된 IgY는 64 kDa의 heavy chain과 27 kDa의 light chain을 가지고 있었다. IgY는 사료 공급 후 위의 pH가 3.4로 낮아지는 2시간째에는 대부분의 활성을 상실하였으나, 장내에서는 IgY의 활성이 나타났다. IgY의 효능 실험 결과 감염 초기에 IgY를 20 mg/fish로 공급한 그룹은 모든 실험에서 대조 그룹에 비해 높은 생존율을 나타내었으며, 장기 내에서 균의 감염 정도 역시 낮았다. 그러나 감염 후기에서는 생존율에 있어서의 유의적인 차이를 확인하기 힘들었다. 이는 넙치의 위에서 대부분의 IgY가 활성을 잃어 낮은 농도만이 장으로 이동하기 때문일 것으로 사료되며, 이 농도에서 IgY는 E. tarda에 대한 뚜렷한 예방이나 치료의 효과 보다는 감염시기를 어느 정도 연장시키는 역할을 하는 것으로 추정된다.

• BMB Reports
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• 제52권12호
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• pp.671-678
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• 2019

The random V(D)J recombination process ensures the diversity of the primary immunoglobulin (Ig) repertoire. In two thirds of cases, imprecise recombination between variable (V), diversity (D), and joining (J) segments induces a frameshift in the open reading frame that leads to the appearance of premature termination codons (PTCs). Thus, many B lineage cells harbour biallelic V(D)J-rearrangements of Ig heavy or light chain genes, with a productively-recombined allele encoding the functional Ig chain and a nonproductive allele potentially encoding truncated Ig polypeptides. Since the pattern of Ig gene expression is mostly biallelic, transcription initiated from nonproductive Ig alleles generates considerable amounts of primary transcripts with out-of-frame V(D)J junctions. How RNA surveillance pathways cooperate to control the noise from nonproductive Ig genes will be discussed in this review, focusing on the benefits of nonsense- mediated mRNA decay (NMD) activation during B-cell development and detrimental effects of nonsense-associated altered splicing (NAS) in terminally differentiated plasma cells.