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Liu YC, Li YY, Yao XJ, Qi HL, Wei XX, Liu JN. Binding Performance of Human Intravenous Immunoglobulin and 20( S)-7-Ethylcamptothecin. Molecules 2018; 23:E2389. [PMID: 30231526 PMCID: PMC6225142 DOI: 10.3390/molecules23092389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Revised: 08/20/2018] [Accepted: 09/12/2018] [Indexed: 11/25/2022] Open
Abstract
A previous study showed that intravenous immunoglobulin (IVIG) could preserve higher levels of biologically active lactone moieties of topotecan, 7-ethyl-10-hydroxycamptothecin (SN-38) and 10-hydroxycamptothecin at physiological pH 7.40. As one of camptothecin analogues (CPTs), the interaction of 7-ethylcamptothecin and IVIG was studied in vitro in this study. It was shown that the main binding mode of IVIG to 7-ethylcamptothecin was hydrophobic interaction and hydrogen bonding, which is a non-specific and spontaneous interaction. The hydrophobic antigen-binding cavity of IgG would enwrap the drug into a host-guest inclusion complex and prevent hydrolysis of the encapsulated drug, while the drug is adjacent to the chromophores of IgG and may exchange energy with chromophores and quench the fluorescence of the protein. Also, the typical β-sheet structure of IVIG unfolded partially after binding to 7-ethylcamptothecin. Additionally, the binding properties of IVIG and six CPTs with different substituents at A-ring and/or B-ring including camptothecin, topotecan, irinotecan, 10-hydroxycamptothecin, 7-ethylcamptothecin and SN-38 were collected together and compared each other. Synergizing with anti-cancer drugs, IVIG could be used as a transporter protein for 7-ethylcamptothecin and other CPTs, allowing clinicians to devise new treatment protocols for patients.
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Affiliation(s)
- Yong-Chun Liu
- College of Chemistry and Chemical Engineering, Longdong University, Qingyang 745000, China.
- Longdong University & FLUOBON Collaborative Innovation Center, Longdong University, Qingyang 745000, China.
| | - Ying-Ying Li
- College of Chemistry and Chemical Engineering, Longdong University, Qingyang 745000, China.
- Longdong University & FLUOBON Collaborative Innovation Center, Longdong University, Qingyang 745000, China.
| | - Xiao-Jun Yao
- College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, China.
| | - Hui-Li Qi
- College of Chemistry and Chemical Engineering, Longdong University, Qingyang 745000, China.
- Longdong University & FLUOBON Collaborative Innovation Center, Longdong University, Qingyang 745000, China.
| | - Xiao-Xia Wei
- College of Chemistry and Chemical Engineering, Longdong University, Qingyang 745000, China.
- Longdong University & FLUOBON Collaborative Innovation Center, Longdong University, Qingyang 745000, China.
| | - Jian-Ning Liu
- College of Chemistry and Chemical Engineering, Longdong University, Qingyang 745000, China.
- Longdong University & FLUOBON Collaborative Innovation Center, Longdong University, Qingyang 745000, China.
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Liu Y, Li Y, Yao X, Li Y, Qi H, Zhang K, Lei R, Liu J. Interaction of intravenous immunoglobulin and three 20(S)-camptothecin analogs: maintaining higher circulatory levels of the biologically active species. Med Chem Res 2017. [DOI: 10.1007/s00044-017-2021-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Cérutti M, Golay J. Lepidopteran cells, an alternative for the production of recombinant antibodies? MAbs 2012; 4:294-309. [PMID: 22531440 DOI: 10.4161/mabs.19942] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Monoclonal antibodies are used with great success in many different therapeutic domains. In order to satisfy the growing demand and to lower the production cost of these molecules, many alternative systems have been explored. Among them, the baculovirus/insect cells system is a good candidate. This system is very safe, given that the baculoviruses have a highly restricted host range and they are not pathogenic to vertebrates or plants. But the major asset is the speed with which it is possible to obtain very stable recombinant viruses capable of producing fully active proteins whose glycosylation pattern can be modulated to make it similar to the human one. These features could ultimately make the difference by enabling the production of antibodies with very low costs. However, efforts are still needed, in particular to increase production rates and thus make this system commercially viable for the production of these therapeutic agents.
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Affiliation(s)
- Martine Cérutti
- CNRS UPS3044 Baculovirus et Thérapie, CNRS GDR3260, ACCITH Anticorps et Ciblage Thérapeutique and LabEx MabImprove, Saint Christol Lèz Alès, France.
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Liu YC, Yang ZY, Du J, Yao XJ, Lei RX, Zheng XD, Liu JN, Hu HS, Li H. Study on the interactions of kaempferol and quercetin with intravenous immunoglobulin by fluorescence quenching, fourier transformation infrared spectroscopy and circular dichroism spectroscopy. Chem Pharm Bull (Tokyo) 2008; 56:443-451. [PMID: 18379088 DOI: 10.1248/cpb.56.443] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/24/2023]
Abstract
The interactions of kaempferol and quercetin with intravenous immunoglobulin (IVIG) were studied in vitro by spectroscopic methods including fluorescence spectra, Fourier transformation infrared (FT-IR) spectra and circular dichroism (CD) spectra. The binding parameters for the reactions calculated according to the Sips equation suggested that the bindings of IVIG to kaempferol and quercetin were characterized by two binding sites with the average affinity constants K(o) at 1.032 x 10(4) M(-1) and 1.849 x 10(4) M(-1), respectively. The binding of IVIG with quercetin is stronger than that of IVIG with kaempferol. They were of non-specific and weak drug-protein interactions. Docking was used to calculate the interaction modes between kaempferol and quercetin with IVIG. The secondary structural compositions of free IVIG and its kaempferol, quercetin complexes were calculated by the FT-IR difference spectra, self-deconvolution, second derivative resolution enhancement and the curve-fitting procedures of amide I band respectively, which are in good agreement with the analyses of CD spectra. The effect of 3'-OH substituent in quercetin is distinct between the interactions of IVIG with kaempferol and quercetin for the secondary structure of the protein. The observed spectral changes indicate a partial unfolding of the protein structure, but the typical beta structural conformation of IVIG is still retentive in the presence of both drugs in aqueous solution. The average binding distances between the chromophores of IVIG with kaempferol (4.30 nm) and quercetin (4.35 nm) were obtained on the basis of the theory of Förster energy transfer. IVIG can serve as transport protein (carrier) for kaempferol and quercetin.
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Affiliation(s)
- Yong-Chun Liu
- College of Chemistry and Chemical Engineering, State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou, PR China
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Interaction of Taxol with intravenous immunoglobulin: An inhibition of Taxol from crystallizing in aqueous solution. Int Immunopharmacol 2008; 8:390-400. [PMID: 18279793 DOI: 10.1016/j.intimp.2007.10.025] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2007] [Revised: 10/15/2007] [Accepted: 10/30/2007] [Indexed: 11/22/2022]
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6
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Liu Y, Lei R, Hu Z, Chen X, Shen F, Jing J. Studies on the Binding of Barbaloin to Human Gamma Globulin. SPECTROSCOPY LETTERS 2006; 39:265-284. [DOI: 10.1080/00387010600636999] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/24/2023]
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Liu Y, He W, Gao W, Hu Z, Chen X. Binding of wogonin to human gammaglobulin. Int J Biol Macromol 2005; 37:1-11. [PMID: 16242767 DOI: 10.1016/j.ijbiomac.2005.04.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2005] [Revised: 04/13/2005] [Accepted: 04/19/2005] [Indexed: 11/18/2022]
Abstract
The binding of wogonin to HGG was studied by spectroscopic method including circular dichroism (CD), fourier transformation infrared spectra (FT-IR), fluorescence spectra. The binding parameters and the thermodynamic parameters for the reaction have been calculated according to Sips method and Gibbs-Helmholtz equation, respectively, at different temperatures. AutoDock3.05 program was used to calculate the interaction modes between the drug and HGG. The Sips plots indicated that the binding of HGG to wogonin at 297, 304, 310 and 317 K is characterized by two binding sites with the average affinity constant Ko at 2.102x10(4), 2.078x10(4), 1.956x10(4) and 1.931x10(4), respectively. The binding process was exothermic, spontaneous and entropy driven, as indicated by the thermodynamic analyses, and the major part of binding energy is electrostatic interaction accompanied by hydrophobic interaction and hydrogen bond. The secondary structure compositions of free HGG and its wogonin complexes were estimated by the FT-IR spectra and the curve-fitted results of amide I band, which are in good agreement with the analyses of CD spectra. Furthermore, the average binding distance between wogonin and HGG (5.60 nm) was obtained on the basis of the theory of Förster energy transfer.
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Affiliation(s)
- Yongchun Liu
- College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, PR China
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8
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Kolar GR, Capra JD. Ig V region restrictions in human chronic lymphocytic leukemia suggest some cases have a common origin. J Clin Invest 2004; 113:952-4. [PMID: 15057298 PMCID: PMC379330 DOI: 10.1172/jci21412] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
The factors that contribute to the development of B cell chronic lymphocytic leukemia (B-CLL) are unknown, and the groups of individuals at the greatest risk for developing this common leukemia are not well defined. Molecular features are important for classifying cases of B-CLL, and it is now apparent that similarities among Ig rearrangements between patients may give important clues to the origin of this disease.
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Affiliation(s)
- Grant R Kolar
- Program in Molecular Immunogenetics, Oklahoma Medical Research Foundation, Oklahoma City 73104, USA
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Andris-Widhopf J, Rader C, Steinberger P, Fuller R, Barbas CF. Methods for the generation of chicken monoclonal antibody fragments by phage display. J Immunol Methods 2000; 242:159-81. [PMID: 10986398 DOI: 10.1016/s0022-1759(00)00221-0] [Citation(s) in RCA: 163] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Phage display has become an important approach for the preparation of monoclonal antibodies from both immune and nonimmune sources. This approach allows for the rapid selection of monoclonal antibodies without the restraints of the conventional hybridoma approach. Although antibodies to a wide variety of antigens have been selected using phage display, some highly conserved mammalian antigens have proven to be less immunogenic in mammalian animals commonly used for immunization. In order to optimize methods for constructing chicken immunoglobulin phage display libraries in the pComb3 system, we have immunized chickens with the hapten fluorescein, and generated combinatorial antibody libraries from spleen and bone marrow RNA. Herein we present methods for the isolation of scFv, diabody and Fab fragment libraries from chickens. Chicken Fab fragment libraries are constructed using human constant regions, facilitating detection with readily available reagents as well as humanization. Analysis of the selected V-genes revealed that gene conversion events were more extensive in light-chain variable region genes as compared to heavy-chain variable region genes. In addition, we present a new variant of the pComb3 phage display vector system.
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Affiliation(s)
- J Andris-Widhopf
- The Scripps Research Institute, Department of Molecular Biology, 10550 North Torrey Pines Road, La Jolla, CA 92307, USA
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Tsantili P, Tzartos SJ, Mamalaki A. High affinity single-chain Fv antibody fragments protecting the human nicotinic acetylcholine receptor. J Neuroimmunol 1999; 94:15-27. [PMID: 10376932 DOI: 10.1016/s0165-5728(98)00195-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Univalent antibody fragments directed against the main immunogenic region (MIR) of the human acetylcholine receptor (AChR) are capable of protecting the AChR against loss induced by antibodies from myasthenia gravis (MG) patients. Our aim was to construct single-chain Fv (scFv) antibody fragments as a first step towards the production of therapeutic protecting molecules, from two high-affinity anti-MIR monoclonal antibodies (mAb 192 and mAb 195). During the construction of scFv192 fragment, two light chains co-secreted from the hybridoma mAb192 were identified. N-terminal amino acid and cDNA sequence analysis showed that one of the two light chains corresponded to the antigen binding molecule while the other originated from the non-secreting myeloma S194/5.XXO.BU.1 which was used in the production of the hybridoma. Functional scFv 192 and 195 fragments were constructed, expressed in Escherichia coli and affinity purified. The binding affinities of scFv192 and scFv195 (K(D) = 0.6 and 0.8 nM for human AChR) were two orders of magnitude higher than that of the earlier constructed scFv198. The scFv192 almost completely protected human AChR against binding of intact anti-MIR mAbs. Human AChR was also very efficiently protected (74-85%) by the scFv192 against binding of autoantibodies from MG sera with high anti-alpha subunit antibody fractions. These scFvs are good candidates for protection of MG patients after appropriate genetic modifications.
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Affiliation(s)
- P Tsantili
- Department of Biochemistry, Hellenic Pasteur Institute, Athens, Greece
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Lucas AH, Moulton KD, Reason DC. Role of κII-A2 Light Chain CDR-3 Junctional Residues in Human Antibody Binding to the Haemophilus influenzae Type b Polysaccharide. THE JOURNAL OF IMMUNOLOGY 1998. [DOI: 10.4049/jimmunol.161.7.3776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Abstract
Abs using the κII-A2 V gene segment predominate the human Ab repertoire to the Haemophilus influenzae b (Hib) polysaccharide (PS). All A2 anti-Hib PS Abs sequenced to date possess a 10-amino acid L chain complementarity-determining region-3 (CDR-3) having an insertional arginine (Arg) at position 95a, the V-J junction. These findings suggest an essential requirement for this conserved Arg residue in determining Hib PS-binding affinity. We examined this requirement by performing chain recombination experiments in which a series of A2 L chains, differing at position 95a, were combined individually with an Fd region known to generate a Hib PS-combining site when paired with an A2-Arg(95a)-Jκ1 V region. Hib PS binding of the recombinant Fabs was evaluated quantitatively using a radioantigen-binding assay. Fabs having A2 L chains with either Arg or lysine in position 95a in combination with Jκ1 gave equivalent and strongest binding to Hib PS. Fabs having A2-Jκ1 L chains with either tyrosine, glycine, alanine, leucine, serine, or threonine in position 95a, or having an A2-Arg(95a)-Jκ3 L chain, gave intermediate binding. Fabs having A2-Jκ1 L chains with glutamate or aspartate at 95a or with no junctional residue showed little or no Hib PS binding. These results demonstrate the importance of L chain junctional residue, as well as Jκ usage and CDR-3 length, in determining Hib PS-binding affinity. Contrary to expectation, an Arg junctional residue is not essential for generating either high or intermediate affinity-binding sites.
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Affiliation(s)
| | - Karen D. Moulton
- Children’s Hospital Oakland Research Institute, Oakland, CA 94609
| | - Donald C. Reason
- Children’s Hospital Oakland Research Institute, Oakland, CA 94609
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Jang YJ, Lecerf JM, Stollar BD. Heavy chain dominance in the binding of DNA by a lupus mouse monoclonal autoantibody. Mol Immunol 1996; 33:197-210. [PMID: 8649441 DOI: 10.1016/0161-5890(95)00094-1] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Antibodies H241 and 2C10 are lupus mouse IgG autoantibodies that bind native DNA. In previous experiments, oligonucleotide antigens affinity-labeled both H and L chains of H241 but only the H chain of antibody 2C10. Primary structures of the V regions of the 2C10 H and L chains and the H241 L chain, determined from cDNA, help to explain the previous affinity-labeling experiments. The 2C10 L chain CDRs had several Asp residues and a net negative charge of five, whereas the 2C10 H chain CDRs had four Arg residues and a net positive charge of five. The L chain CDRs of H241 had a net positive charge of one. [The H241 H chain cDNA sequence was published previously by Gangemi et al. (1993) J. Immun. 151, 4660-4671]. Plasmid vectors were used for bacterial expression of H and L chains of 2C10 alone and in combinations in single chain Fv (scFv) molecules. The H chain alone bound native DNA as well as or better than the H-plus-L chain scFv. The H chain alone also bound Z-DNA. Combination of the 2C10 H chain with the L chain of an anti-Z-DNA antibody maintained the selectivity for Z-DNA, whereas its combination with the 2C10 L chain (in the 2C10 Fab) yielded selective B-DNA binding. The results with 2C10 match other examples in which the H chain is sufficient for DNA binding but selectivity is modulated by the L chain. The H chain binding to autoantigen may reflect selective events in early stages of B cell development.
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Affiliation(s)
- Y J Jang
- Department of Biochemistry, Tufts University School of Medicine, Boston, MA 02111, USA
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Lake DF, Lam KS, Peng L, Hersh EM. Molecular cloning, expression and mutagenesis of an anti-insulin single chain Fv (scFv). Mol Immunol 1994; 31:845-56. [PMID: 8047074 DOI: 10.1016/0161-5890(94)90022-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The immunoglobulin variable region genes of a murine anti-insulin IgG-producing hybridoma were rescued and cloned into a bacterial expression vector. The variable regions of the gamma heavy chain and the kappa light chain were expressed independently and together as a single chain antibody (scFv). The variable heavy chain alone demonstrated the ability to bind to insulin. The kappa light chain did not show any binding activity towards insulin. The scFv was constructed by PCR assembly using a (Gly4Ser)3 linker between the carboxyl end of the variable heavy chain and the amino terminus of the kappa light chain. The scFv bound insulin at an IC50 of 3.5 x 10(-8) M whereas the parent antibody bound insulin at 1.0 x 10(-8) M. Mutagenesis of the variable heavy chain complementarity determining regions (CDR) indicated that CDR1 and CDR3 were important for binding to insulin. Position 99 in CDR3 of the heavy chain was found to be a critical position for the ability of the scFv to bind to insulin.
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Affiliation(s)
- D F Lake
- Department of Microbiology, University of Arizona, Tucson 85724
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Azmi FH, Lucas AH, Raff HV, Granoff DM. Variable region sequences and idiotypic expression of a protective human immunoglobulin M antibody to capsular polysaccharides of Neisseria meningitidis group B and Escherichia coli K1. Infect Immun 1994; 62:1776-86. [PMID: 8168940 PMCID: PMC186406 DOI: 10.1128/iai.62.5.1776-1786.1994] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
We determined the heavy (H)- and light (L)-chain variable (V) region nucleotide and translated amino acid sequences of the human immunoglobulin M(kappa) monoclonal antibody (MAb) 5E1, which is specific for the polysaccharide capsule of Escherichia coli K1 and Neisseria meningitidis group B (poly[alpha(2-->8)-N-acetylneuraminic acid]) and which is protective in animal models of infection. The 5E1 VH gene is a member of the VHIIIb family and is 97% homologous to the 9.1 germ line gene. The 5E1 VL gene is a member of the kappa I subgroup and is 98% homologous to the germ line gene, 15A, also known as KLO12. The VL and/or VH genes used by 5E1 are highly homologous to the V genes encoding antibodies to the Haemophilus influenzae type b polysaccharide and to antibodies reactive with self-antigens such as erythrocyte "i," DNA, and thyroid peroxidase. We also produced three murine anti-idiotype (Id) MAbs against 5E1. All three anti-Ids recognize a minor subset of antimeningococcal B polysaccharide antibodies present in serum from normal adults. Two of the anti-Ids define distinct Ids associated with antibodies having kappa I-15A V regions. These 15A-associated Ids are expressed by some heterologous human antimeningococcal B polysaccharide MAbs, and they also are independently expressed by two human MAbs that are specific for either the H. influenzae b polysaccharide or the i erythrocyte antigen and that utilize the kappa I-15A V region. Taken together, these data indicate that the 5E1 antibody uses V regions that recur in the human antibody repertoires to this polysaccharide and to structurally dissimilar polysaccharides and autoantigens. Thus, the poor immunogenicity of poly[alpha(2-->8)-N-acetylneuraminic acid] cannot be explained by the unavailability of certain critical VH and VL genes required for generation of antibody response.
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Affiliation(s)
- F H Azmi
- Edward Mallinckrodt Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri
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Panka DJ, Very DL, Jacobson BA, Kussie PH, Parhami-Seren B, Margolies MN, Marshak-Rothstein A. Defining the structural correlates responsible for loss of arsonate affinity in an IDCR antibody isolated from an autoimmune mouse. Mol Immunol 1993; 30:1013-20. [PMID: 8350871 DOI: 10.1016/0161-5890(93)90126-v] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Immunization of the autoimmune mouse strain (M x A) Id/lpr with Ars-KLH, has been shown to elicit a prolonged anti-Ars IdCR response similar to that found in A/J mice. Cell fusion of splenocytes from a diseased mouse previously immunized with Ars-KLH resulted in a monoclonal antibody, 1-52.30, that was found to express the strain A major cross-reactive idiotype, but failed to bind Ars. Nucleotide sequence analysis demonstrated that 1-52.30: (a) used the "canonical" combination of gene segments associated with this idiotype, and (b) exhibited a pattern of somatic mutation consistent with selection for high affinity Ars binding. Two amino acids, VL 91 and 93, were mutated in 36-65, the germline equivalent of the IdCR antibodies, to 1-52.30-like residues (91G-->D, 93T-->M). The results of the mutagenesis showed that changing a single light chain residue, VL 91, from glycine to aspartic acid, resulted in a dramatic loss of Ars binding activity.
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Affiliation(s)
- D J Panka
- Department of Microbiology, Boston University Medical School, MA 02118
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