Bifunctional NHS-BAT ester for antibody conjugation and stable technetium-99m labeling: conjugation chemistry, immunoreactivity and kit formulation
<p>Conjugation chemistry and kit formulated binding of the NHS ester of 6-(4′-(4″-carboxyphenoxy)buty9-2, 10-dimercapto-2,10-dimethyl-4,8-diazaundecane (NHS-BAT ester) to monoclonal antibodies (MAbs) was investigated. The functionalities of the resulting BAT conjugated and <sup>99m</s...
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| Hauptverfasser: | , , , , , , , , , , |
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| Dokumenttyp: | Article (Journal) |
| Sprache: | Englisch |
| Veröffentlicht: |
February 1, 1996
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| In: |
Journal of nuclear medicine
Year: 1996, Jahrgang: 37, Heft: 2, Pages: 362-370 |
| ISSN: | 2159-662X |
| Online-Zugang: | Verlag, lizenzpflichtig, Volltext: https://jnm.snmjournals.org/content/37/2/362
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| Verfasserangaben: | M. Eisenhut, W.D. Lehmann, W. Becker, T. Behr, H. Elser, W. Strittmatter, A. Steinsträsser, R.P. Baum, T. Valerius, R. Repp, Y. Deo |
| Zusammenfassung: | <p>Conjugation chemistry and kit formulated binding of the NHS ester of 6-(4′-(4″-carboxyphenoxy)buty9-2, 10-dimercapto-2,10-dimethyl-4,8-diazaundecane (NHS-BAT ester) to monoclonal antibodies (MAbs) was investigated. The functionalities of the resulting BAT conjugated and <sup>99m</sup>Tc-labeled MAbs BW 431/26, MAb 425 and bispecific MDX210 (fragment construct) were tested by immunoreactivity and immunoscintigraphy. <b>Methods:</b> The kinetics and chemistry of the conjugation reaction were monitored by high-performance liquid chromatography, size-exclusion chromatography and positive fast-atom-bombardment mass spectra (FAB-MS). The <sup>99m</sup>Tc BAT-MAbs were tested with various immunoreactivity as says. The biodistribution of <sup>99m</sup>Tc-BAT-BW 431/26 in rats was compared with directly labeled BW 431/26. <b>Results:</b> At pH 8.5 and 25°C,the reactivity of the NHS-BAT ester was high with 90% completion after 30 min. The conjugation yield of 19 μM MAb and 228 μM NHS-BAT ester amounted to 30%. Higher NHS-BAT ester concentrations afforded higher BAT-to-MAb ratios. According to FAB-MS, the conjugation competing hydrolysis surprisingly occurred at the NHS ring. Almost quantitative <sup>99m</sup>Tc labeling was achieved after 5 min at 25°C. Immunoreactivity of the <sup>99m</sup>Tc-BAT antibodies showed >90% recovery and proved to be insensitive to BAT-to-MAb ratios of up to 10. The <sup>99m</sup>Tc-BAT-BW 431/26 showed similar organ distribution but revealed less urinary excretion compared with the directly labeled BW 431/26. Immunoscintigraphy with <sup>99m</sup>Tc-labeled and BAT-BW 431/26 and BAT-MAb 425 showed the respective biological function in vivo. <b>Conclusion:</b> According to straightforward conjugation chemistry, the ease of <sup>99m</sup>Tc labeling and the application of a simple ultrafiltration technique, the NHS BAT ester represents a nondestructive, universally applicable bifunctional ligand to introduce stable <sup>99m</sup>Tc protein binding sites. Kit formulated conjugation/labeling can be performed with little time requirements and laboratory experience.</p> |
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| Beschreibung: | Gesehen am 05.12.2024 |
| Beschreibung: | Online Resource |
| ISSN: | 2159-662X |