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Uthoff S, Böldicke T. In vitro immunization of mouse spleen cells for the production of monoclonal IgG1 antibodies using an antigen-specific T helper cell clone (D.10.G4.1). J Immunol Methods 1993; 166:165-75. [PMID: 7507145 DOI: 10.1016/0022-1759(93)90357-d] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The in vitro immunization of mouse spleen cells for the production of antigen-specific monoclonal antibodies has been investigated in detail. Using various, previous published in vitro immunization protocols with and without antigen, we were able to show that IgM antibody production was not induced by the antigen. Nevertheless we developed a new in vitro immunization protocol for eliciting antigen-specific monoclonal IgG1 antibodies. Specific antibodies were generated by an antigen-driven immune response which included an immunoglobulin class switch. Co-culture of mouse spleen cells with an activated conalbumin specific T helper cell clone (TH2 D.10.G4.1) in the presence of conalbumin elicited three monoclonal IgG1 antibodies that bound specifically to conalbumin. We conclude that for the in vitro generation of monoclonal antibodies against T cell dependent proteins the addition of antigen activated specific TH2 cell clones is essential.
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Affiliation(s)
- S Uthoff
- Gesellschaft für Biotechnologische Forschung, Department of Genetics, Braunschweig, Germany
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2
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Federspiel G, McCullough KC, Kihm U. Production of monoclonal antibodies specific for African swine fever virus following in vitro primary immunization of mouse splenocytes in the presence of stimulated T lymphocyte supernatants. J Immunol Methods 1991; 145:71-81. [PMID: 1765668 DOI: 10.1016/0022-1759(91)90312-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Splenocytes from non-immune mice were stimulated in vitro using a kit of cytokine preparations (obtained from murine MLR and EL-4 cell cultures), and concomitantly immunized with African swine fever (ASF) virus antigen. In addition, fusions were performed at 5 days after primary or secondary stimulation/immunization. The detection of specific antibodies in the culture supernatants was not successful. In contrast, specific antibody-producing hybridomas could be generated, and this was at least comparable to a standard in vivo immunization regime, even though the optimum fusion ratio employed with these in vitro immunized splenocytes was one which is not optimum when in vivo immunized lymphocytes are used. Consequently, it would appear that hybridoma generation is a more sensitive method than the direct measurement of antibody at detecting in vitro primary immune responses. After primary in vitro immunization, the majority of immunoglobulins produced were apparently of the IgG isotype, with only 8-17% clearly IgM. These antibodies were mainly against VP73 (the major viral envelope protein) as expressed on viral antigen extracted from infected cells, although other specificities were also found. This demonstrated, by in vitro means, that the VP73 carried dominant immunogenic epitopes on ASF virus. Such observations show that the in vitro responses were closely related to those which have been detected in vivo.
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Affiliation(s)
- G Federspiel
- Institut für Viruskrankheiten und Immunprophylaxe (IVI), Basel, Switzerland
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3
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Enriquez FJ, Bradley-Dunlop D, Joens L. Increased proportion of antigen-specific antibody-producing hybridomas following an in vitro immunization with in vivo immunized mouse spleen cells. Hybridoma (Larchmt) 1991; 10:745-51. [PMID: 1816073 DOI: 10.1089/hyb.1991.10.745] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Development of murine monoclonal antibodies to weakly immunogenic antigens was accomplished by combining both in vivo and in vitro immunizations. Following immunization of mice with Treponema hyodysenteriae outer membrane antigens, Manduca sexta apolipoproteins, and Drosophila melanogaster DNA polymerase, respectively, a significant increase in percentage of antibody-producing hybrids were identified when immune spleens were subjected to an in vitro immunization prior to fusion with SP2/0 myeloma cells. The hybrids developed, produced Abs to a T. hyodysenteriae 14 Kd carbohydrate, M. sexta apolipoproteins I, II, and III, and D. melanogaster DNA polymerase. The use of both in vivo and in vitro immunizations may increase the likelihood of generating monoclonal antibodies to weakly immunogenic antigens.
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Affiliation(s)
- F J Enriquez
- Hybridoma Technology, Arizona Health Sciences Center, Tucson
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4
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Khachigian LM, Evin G, Morgan FJ, Owensby DA, Chesterman CN. A crossreactive antipeptide monoclonal antibody with specificity for lysyl-lysine. J Immunol Methods 1991; 140:249-58. [PMID: 1712372 DOI: 10.1016/0022-1759(91)90378-s] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Synthetic peptides meeting certain guidelines have been used as immunogens to generate antibodies with predefined specificity. We have raised and characterized using established methods a monoclonal antibody against a synthetic peptide corresponding to the 18-amino acid carboxyterminal sequence (A194-211) of the platelet-derived growth factor (PDGF) A chain expressed by the U343 human glioma cell line. This antibody was generated in order to carry out structure-function studies on this region of PDGF whose biological significance is not yet clear. Anti-PDGF-A194-211 was found to be a low titre, IgM kappa molecule, with a Kd of 2.8 x 10(-7) M. When antibody reactivity was tested with parent PDGF-AAL (A chain homodimer containing a carboxyterminal extension) significant binding was observed. Surprisingly, 125I-PDGF-AAS, consisting of truncated A chains but lacking the extension was also bound. Moreover, poly-L-lysine, beta-thromboglobulin, PDGF-A194-211, and myoglobin competed dose-dependently with 125I-PDGF-AAL for antibody. 125I-bovine serum albumin was also bound. Examination of the primary sequence of proteins and peptides bound by the antibody revealed only one shared structural motif: a lysyl-lysine moiety. Selected small synthetic peptides containing this and other sequences were used as potential competitors of 125I-PDGF-A194-211 in antibody binding. Lysyl-lysyl-glycyl-glutamic acid [corrected] and lysyl-lysine competed, whereas lysyl-leucine did not. These results suggest that as few as two amino acid residues constitute a functional antigenic determinant and contrast with most previous estimates of the minimum number of residues required. Furthermore, we show that guidelines governing the design of synthetic peptides for their use as antigens to produce monoclonal antibodies of predetermined specificity may be unreliable.
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Affiliation(s)
- L M Khachigian
- Department of Hematology, University of New South Wales, Prince of Wales Hospital, Randwick, NSW, Australia
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5
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Shibier O, Hampton SM, Marks V. An immunisation protocol which enhances the frequency of antigen-specific monoclonal antibody production. J Immunol Methods 1988; 114:49-52. [PMID: 2460563 DOI: 10.1016/0022-1759(88)90152-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
An immunisation protocol has been developed for small molecular weight antigens which results in a high percentage of specific hybridomas being produced after cell fusion. An enzyme-linked immunosorbent assay (ELISA) was developed for screening the desired antibodies in the culture supernatants. A conventional immunisation regimen was followed by doses of antigen in sterile water on each of the last 4 days before fusion. A range of antigen doses was used and the specific efficiency of fusion was increased by selection of the optimum amount. The antigen used as a model antigen in these experiments was biosynthetic human insulin.
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Affiliation(s)
- O Shibier
- Department of Biochemistry, University of Surrey, Guildford, U.K
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6
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Critical appraisal of the in vitro immunization technology for the production of mouse and human monoclonal antibodies. Adv Drug Deliv Rev 1988. [DOI: 10.1016/0169-409x(88)90031-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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7
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Böldicke T, Kindt S, Maywald F, Fitzlaff G, Böcher M, Frank R, Collins J. Production of specific monoclonal antibodies against the active sites of human pancreatic secretory trypsin inhibitor variants by in vitro immunization with synthetic peptides. EUROPEAN JOURNAL OF BIOCHEMISTRY 1988; 175:259-64. [PMID: 3402453 DOI: 10.1111/j.1432-1033.1988.tb14191.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Specific monoclonal antibodies against the active sites of two genetically engineered pancreatic secretory trypsin inhibitor (PSTI) variants (PSTI 0 and PSTI 4) were produced. The protease inhibitors PSTI 0 and PSTI 4 differ only by three amino acid substitution at their active sites. PSTI 0 inhibits trypsin, whereas PSTI 4 inhibits human granulocyte elastase and chymotrypsin. Immunization was performed in vitro with a synthetic heptapeptide that covers the mutated region of the protein. For this purpose in vitro culture conditions for the production of specific monoclonal antibodies against synthetic peptides were improved. The monoclonal antibodies obtained react specifically with the corresponding protease inhibitor variant. Competition experiments with trypsin and human elastase demonstrate that the protease displace the monoclonal antibody from the active site of PSTI 0 and PSTI 4 respectively.
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Affiliation(s)
- T Böldicke
- Department of Genetics, Gesellschaft für Biotechnologische Forschung mbH, Braunschweig, Federal Republic of Germany
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8
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Echtenacher B, Hederer R, Krammer PH. Biological effects of a rat monoclonal anti-mouse IFN-gamma antibody produced by in vitro immunization. Immunobiology 1987; 176:96-107. [PMID: 3129363 DOI: 10.1016/s0171-2985(87)80103-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
This paper describes the biological effect of monoclonal antibodies to murine IFN-gamma produced by in vitro immunization with only several nanograms of rIFN-gamma. Four mAbs binding to rIFN-gamma were selected. mAb U7 was characterized in detail and shown to bind specifically to rIFN-gamma in a Western blot and to specifically inhibit the antiviral effect of rIFN-gamma and natural IFN-gamma. The activities of IFN-alpha, beta and IL2 were not affected. The M phi activating effect of both rIFN-gamma and natural IFN-gamma was also inhibited by mAb U7. Thus, we showed that it is possible to produce specific mAbs with very small amounts of cytokines by in vitro immunization.
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Affiliation(s)
- B Echtenacher
- Institute of Immunology and Genetics, German Cancer Research Center, Heidelberg
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9
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Sheng HZ, Hoogenraad J, Carnegie PR, Bernard CC. Use of protein-bearing nitrocellulose as immunogen for in vitro production of monoclonal antibodies: application to myelin basic protein electrophoretically separated from a complex brain protein mixture. Immunol Lett 1987; 16:75-81. [PMID: 2448235 DOI: 10.1016/0165-2478(87)90065-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
A procedure for producing monoclonal antibody to myelin basic protein (MBP) using in vitro immunization with MBP transferred to nitrocellulose is described. Following the separation of brain proteins by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) and electrophoretic transfer of the electrophoretogram onto nitrocellulose, the MBP band located by immunodetection was excised from the nitrocellulose, ground, and used as immunogen for in vitro stimulation of unprimed mouse spleen cells. While in vitro immunization with soluble MBP was able to generate many hybrids, all the wells in the fusions carried out with the immobilized MBP contained hybrids, 33 to 42% of which were positive to MBP. Among these, six were further characterized; all were IgM and all bound to epitopes common to the 18.5K and 21.5K MBP forms of several species. In view of its simplicity, this technique should have a wide application for the rapid production of monoclonal antibodies to selected proteins or their fragments present in small quantity or difficult to purify on a large scale.
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Affiliation(s)
- H Z Sheng
- Department of Psychology, La Trobe University, Bundoora, Victoria, Australia
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10
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Samoilovich SR, Dugan CB, Macario AJ. Hybridoma technology: new developments of practical interest. J Immunol Methods 1987; 101:153-70. [PMID: 3302047 PMCID: PMC7130749 DOI: 10.1016/0022-1759(87)90147-5] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/1987] [Revised: 03/16/1987] [Accepted: 03/16/1987] [Indexed: 01/05/2023]
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11
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Comitti R, Racchetti G, Gnocchi P, Morandi E, Galante YM. A monoclonal-based, two-site enzyme immunoassay of human insulin. J Immunol Methods 1987; 99:25-37. [PMID: 3553334 DOI: 10.1016/0022-1759(87)90028-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
A procedure is described for the efficient production of insulin-specific monoclonal antibodies, which involves primary and secondary immunization of BALB/c mice in the hind footpads with bovine or porcine insulin and fusion of lymphocytes from popliteal lymph nodes with a P3x63 murine myeloma line. With this protocol, over 200 positive hybrids were obtained from four separate fusions. Dissociation constants of 31 purified monoclonals, cross-reacting with human insulin, were determined by two different methods and ranged between 4 X 10(-10) and 2 X 10(-6) mol/l. 24 monoclonals were biotinylated, paired in all possible combinations and tested by ELISA for their capacity to simultaneously bind to human insulin in a two-site assay. More than 40 monoclonal pairs were found which formed a sandwich with the hormone. The development of a simple and rapid one-step enzyme immunoassay is described, which involves a first monoclonal bound to the wells of a microtiter plate and a second monoclonal conjugated to alkaline phosphatase. With this assay, insulin can be determined in a range between 0.08 and 7.5 ng/ml in 3-4 h.
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12
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Erkman L, Soldati G, James RW, Kato AC. Partial purification of lymphoblasts after in vitro immunization increases the yield in Ig-producing hybridomas. J Immunol Methods 1987; 98:43-52. [PMID: 3031165 DOI: 10.1016/0022-1759(87)90433-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Using in vitro immunization with a human plasma protein (apolipoprotein-A1) as antigen, we have shown that it is possible to prepare more monoclonal antibodies using a ten-fold lower concentration of antigen compared to in vivo immunization procedures (Weech et al., 1985). In addition, we can increase the number of Ig-producing hybridomas after in vitro immunization by a simple one-step separation of the lymphoblasts on a Percoll gradient before the fusion procedure. In order to apply this procedure to in vivo immunization techniques, it is necessary to expand the B-blast/plasma cell population by culturing the spleen cells for 4-6 days before fusion. Only antibodies of the IgM class were produced with the in vitro technique. However, by combining in vivo priming with in vitro immunization, it is possible to produce specific antibodies to both IgG and IgM classes.
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Brams P, Pettijohn DE, Brown M, Olsson L. In vitro B-lymphocyte antigen priming against both non-immunogenic and immunogenic molecules requiring low amounts of antigen and applicable in hybridoma technology. J Immunol Methods 1987; 98:11-22. [PMID: 2435806 DOI: 10.1016/0022-1759(87)90430-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
A method to efficiently antigen-prime B-lymphocytes with low amounts (less than 1 microgram/10(8) cells) of either immunogenic or non-immunogenic molecules is described. Keyhole limpet hemocyanin (KLH) and histone were used as prototypes for strongly immunogenic and for phylogenetically conserved non-immunogenic epitopes, respectively. Several modifications of previously reported methods were applied to the system and resulted in the requirement of antigen amounts sufficiently low to be obtainable by elution of proteins from electrophoretic gels. Antigen priming against highly purified antigen preparations is thereby feasible even when purified material cannot be obtained by conventional biochemical procedures. The amount of T- and B-lymphocytes and interleukin-2 production was estimated under various conditions during the priming procedure, and those optimal for generation of a high number of antigen-specific B-lymphocytes determined. In vitro antigen-primed B-lymphocytes were immortalized by conventional hybridoma technology. By fusion of lymphoid cells with myeloma cells at each day during the antigen-priming period, the optimal day of fusion to generate antigen-specific hybridomas was determined. Further, in 12 experiments with different antigens, 11 monoclonal antibodies to histones H3 and H4, two to the murine glucose transporter, 17 to trinitrophenyl-sheep red blood cells, and 20 to KLH were obtained. All specific hybridomas produced IgMs, as the antigen-priming period could not be extended for more than 9-10 days, whereafter a rapid decay in B-lymphocytes occurred.
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14
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Takahashi M, Fuller SA, Hurrell JG. Production of IgG-producing hybridomas by in vitro stimulation of murine spleen cells. J Immunol Methods 1987; 96:247-53. [PMID: 3492563 DOI: 10.1016/0022-1759(87)90321-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
An in vitro stimulation protocol has been established which allows production of IgG-secreting murine hybridomas. This procedure has been examined using jack bean urease and human luteinizing hormone as antigens. Parameters which have been optimized include selection of media and serum supplements, thymocyte-conditioned media, antigen dosage, length of stimulation and the effect of medium changes during stimulation and additions of polyclonal mitogen. Murine spleen cells (1 X 10(8) in 10 ml) were incubated with varying doses of jack bean urease and human luteinizing hormone in a six-well plate in supplemented DMEM with 5% normal rabbit serum and 10% thymocyte-conditioned media. Following 5 and/or 8 days stimulation, the spleen cells were fused with SP2/0 cells and plated in 96-well plates. Stable hybridomas were obtained for both antigens from over 25% of the wells identified in initial screening for specific antibody production. All monoclonal antibodies obtained in the LH stimulation experiments, with one exception, were of the IgM isotype. A large number of IgG-producing hybridomas were isolated following prolonged (8 day) stimulation with high concentrations of urease, during which time the medium remained unchanged. Addition of polyclonal mitogen (E. coli lipopolysaccharide) at 10 micrograms/ml markedly increased the production of hybridomas secreting anti-urease, but most were of IgM class.
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15
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Borrebaeck CA. Development of in vitro immunization in murine and human hybridoma technology. J Pharm Biomed Anal 1987; 5:783-92. [PMID: 16867454 DOI: 10.1016/0731-7085(87)80096-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/1987] [Indexed: 11/23/2022]
Abstract
The development of in vitro immunization in murine and human hybridoma technology is reviewed. Special consideration is given to: technical aspects of in vitro immunization of mouse B cells; quality of antibodies produced by in vitro immunization; advantages of murine in vitro immunization; technical aspects of in vitro immunization of human B cells; and the advantages of human in vitro immunization and human monoclonal antibodies. Future developments likely to be made in this area of immunotechnology are outlined.
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Affiliation(s)
- C A Borrebaeck
- Department of Biotechnology, University of Lund, P.O. Box 124, S-221 00 Lund, Sweden
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16
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French D, Fischberg E, Buhl S, Scharff MD. The production of more useful monoclonal antibodies I. Modifications of the basic technology. ACTA ACUST UNITED AC 1986; 7:344-6. [DOI: 10.1016/0167-5699(86)90142-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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17
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Khalil A, Bramson N, Kezdy FJ, Kaiser ET, Scanu AM. Affinity of nonhomologous amphiphilic peptides toward a monoclonal antibody raised against apolipoprotein A-I. Proteins 1986; 1:280-6. [PMID: 3130624 DOI: 10.1002/prot.340010311] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Monoclonal antibodies against human apolipoprotein A-I (apoA-I) were generated by the hybridoma technique. Clone G-10 was selected on the basis of its highest titer. The affinity of this antibody toward a series of synthetic peptides differing in length, amino acid composition, and amphiphilicity was tested by using both the indirect and the competitive enzyme-linked immunosorbent techniques (ELISA). From these measurements we calculated dissociation constants of the complexes of the antibody with apoA-I bound to the surface of the microtiter plate, apoA-I in solution, and any of the several peptides in solution. The dissociation constant (Kd) of the immobilized apoA-I/anti-apoA-I-complex, Kd = 2 x 10(-9) M, was significantly lower than that of the complex resulting from the interaction between anti-apoA-I and either apoA-I in solution or any of the several amphiphilic helical peptides in solution. Peptides devoid of amphiphilic secondary structure were inert. These data are consistent with the proposal that monoclonal G-10 recognizes in antigenic peptides an alpha-helical secondary structure of defined hydrophilic-lipophilic balance and comparatively less the specific amino acid side chains. We propose that the highest contribution to the free energy of binding (8 Kcal/mole) is derived from the docking of the helix to the antibody. It follows that in probing the specificity of a monoclonal antibody the conformation and the physical environment of the interacting antigen must be taken into account.
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Affiliation(s)
- A Khalil
- Department of Medicine, University of Chicago, Illinois 60637
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18
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Ossendorp FA, De Boer M, Al BJ, Hilgers J, Bruning PF, Tager JM. Production of murine monoclonal antibodies against human thyroglobulin using an in vitro immunization procedure in serum-free medium. J Immunol Methods 1986; 91:257-64. [PMID: 3488350 DOI: 10.1016/0022-1759(86)90487-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
A serum-free in vitro immunization method for the generation of hybridomas producing specific antibodies to an antigen is described. The method was tested with human thyroglobulin as antigen. The serum-free medium used (Yssel et al., 1984) consisted of Iscove's modification of Dulbecco's modified Eagle's medium, supplemented with albumin, transferrin, insulin, ethanolamine and linoleic, oleic and palmitic acids. An optimal response was obtained when splenocytes from BALB/c mice were cultured for 3 days in the presence of 1.5 nM thyroglobulin and thymocyte-conditioned medium prior to fusion with SP2/0 myeloma cells and seeding of the fused cells in microtitre plates. The frequency of positive wells, defined as the number of wells secreting anti-(thyroglobulin) antibodies/number of viable cells used for the fusion, was 1.6 X 10(-6) +/- 0.25 X 10(-6) (mean +/- SD; n = 4). Eight stable clones producing anti-(thyroglobulin) antibodies were isolated. One clone (3D12) produced antibodies reacting only with human thyroglobulin. The antibodies produced by the other clones reacted with human, murine and porcine thyroglobulins. Seven of the clones produced antibodies of the IgM class and one clone produced IgG. The specificity of 3D12 (IgM) for human thyroglobulin and the absence of any reactivity with murine thyroglobulin provides evidence for a primary response of splenocytes in culture to the presence of an antigen.
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19
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Rathjen DA, Underwood PA. Identification of antigenic determinants on insulin recognized by monoclonal antibodies. Mol Immunol 1986; 23:441-50. [PMID: 2425251 DOI: 10.1016/0161-5890(86)90142-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The specificities of nine monoclonal antibodies raised to bovine insulin were investigated. The probable binding sites of the antibodies were determined by correlation of cross-reactivity with heterologous insulins and amino acid differences in the primary structures. Most antibodies recognized topographic determinants composed of both A- and B-chain residues but were capable of binding either one or both free chains independently. Only one antibody was completely conformation-dependent. A number of antibodies showed heteroclitic binding to particular insulin variants. All the antibodies were autoreactive in that they recognized rat insulin which has the same primary sequence as the mouse molecule.
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20
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Rathjen DA, Geczy CL. Conditioned medium from macrophage cell lines supports the single-cell growth of hybridomas. Hybridoma (Larchmt) 1986; 5:255-61. [PMID: 3770777 DOI: 10.1089/hyb.1986.5.255] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The aim of this study was to establish whether conditioned medium (CM) from macrophage cell lines would support the growth of hybridomas under conditions commonly used in hybridization experiments and in cloning of antigen-specific hybridomas. The ability of CM from macrophage cell lines J774, WEHI 274, WEHI 265, and PU 5 to support single-cell growth during cloning was compared with CM from cultures of resident mouse peritoneal cells, EL 4 mouse thymoma cells, L929 mouse fibrosarcoma, and feeder layers of resident peritoneal cells. CM from J774, L929, and resident peritoneal cells supported single-cell growth at the same level as the macrophage feeder layer. J774 and L929 CM were most effective at a final concentration of 25% with fresh medium supplemented with 20% fetal calf serum (FCS). The ability of J774 CM to support hybridoma growth was increased by prior stimulation with LPS but not PMA. CM from LPS-stimulated J774 cells used in fusion experiments resulted in increased numbers of hybridomas compared with those obtained with macrophage feeder layers.
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