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. 1997;75(7):1035–1043. doi: 10.1038/bjc.1997.177

Comparison of the potency and therapeutic efficacy of the anti-CD7 immunotoxin HB2-saporin constructed with one or two saporin moieties per immunotoxin molecule.

D J Flavell 1, D A Boehm 1, A Noss 1, S U Flavell 1
PMCID: PMC2222741  PMID: 9083340

Abstract

Immunotoxins that carry two toxin molecules to the target cell should in theory have a greater anti-tumour effect than those that carry just one. We have investigated the therapeutic efficacy of two anti-CD7-saporin immunotoxins constructed with one saporin (HB2-Sap 1-mer) or two saporin molecules (HB2-Sap 2-mer) per immunotoxin molecule. In vitro, the 2-mer immunotoxin was 5.6 times more effective than the 1-mer immunotoxin at inhibiting protein synthesis in the CD7+ human T-cell acute lymphoblastic leukaemia (T-ALL) cell line HSB-2 and was also more effective at inhibiting HSB-2 cell proliferation. Flow cytometry revealed that the 2-mer immunotoxin had a reduced binding capacity to HSB-2 cells compared with the 1-mer immunotoxin or native HB2 antibody. In therapy studies in SCID mice with disseminated HSB-2 human leukaemia, the 2-mer immunotoxin performed marginally better than the 1-mer immunotoxin, but log-rank analysis did not reveal any significant differences between the two therapy groups. We therefore conclude that, although the 2-mer immunotoxin performed better than the 1-mer immunotoxin against target HSB-2 cells in vitro, this improved performance was not reflected as an improved in vivo therapeutic outcome in the SCID mouse model.

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Selected References

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  1. Adams R. A., Pothier L., Flowers A., Lazarus H., Farber S., Foley G. E. The question of stemlines in human acute leukemia. Comparison of cells isolated in vitro and in vivo from a patient with acute lymphoblastic leukemia. Exp Cell Res. 1970 Sep;62(1):5–10. doi: 10.1016/0014-4827(79)90504-4. [DOI] [PubMed] [Google Scholar]
  2. Amlot P. L., Stone M. J., Cunningham D., Fay J., Newman J., Collins R., May R., McCarthy M., Richardson J., Ghetie V. A phase I study of an anti-CD22-deglycosylated ricin A chain immunotoxin in the treatment of B-cell lymphomas resistant to conventional therapy. Blood. 1993 Nov 1;82(9):2624–2633. [PubMed] [Google Scholar]
  3. Dorshkind K., Pollack S. B., Bosma M. J., Phillips R. A. Natural killer (NK) cells are present in mice with severe combined immunodeficiency (scid). J Immunol. 1985 Jun;134(6):3798–3801. [PubMed] [Google Scholar]
  4. Falini B., Bolognesi A., Flenghi L., Tazzari P. L., Broe M. K., Stein H., Dürkop H., Aversa F., Corneli P., Pizzolo G. Response of refractory Hodgkin's disease to monoclonal anti-CD30 immunotoxin. Lancet. 1992 May 16;339(8803):1195–1196. doi: 10.1016/0140-6736(92)91135-u. [DOI] [PubMed] [Google Scholar]
  5. Fishwild D. M., Aberle S., Bernhard S. L., Kung A. H. Efficacy of an anti-CD7-ricin A chain immunoconjugate in a novel murine model of human T-cell leukemia. Cancer Res. 1992 Jun 1;52(11):3056–3062. [PubMed] [Google Scholar]
  6. Flavell D. J., Boehm D. A., Emery L., Noss A., Ramsay A., Flavell S. U. Therapy of human B-cell lymphoma bearing SCID mice is more effective with anti-CD19- and anti-CD38-saporin immunotoxins used in combination than with either immunotoxin used alone. Int J Cancer. 1995 Jul 28;62(3):337–344. doi: 10.1002/ijc.2910620318. [DOI] [PubMed] [Google Scholar]
  7. Flavell D. J., Boehm D. A., Okayama K., Kohler J. A., Flavell S. U. Therapy of human T-cell acute lymphoblastic leukaemia in severe combined immunodeficient mice with two different anti-CD7-saporin immunotoxins containing hindered or non-hindered disulphide cross-linkers. Int J Cancer. 1994 Aug 1;58(3):407–414. doi: 10.1002/ijc.2910580317. [DOI] [PubMed] [Google Scholar]
  8. Flavell D. J., Cooper S., Morland B., Flavell S. U. Characteristics and performance of a bispecific F (ab'gamma)2 antibody for delivering saporin to a CD7+ human acute T-cell leukaemia cell line. Br J Cancer. 1991 Aug;64(2):274–280. doi: 10.1038/bjc.1991.291. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Flavell D. J., Cooper S., Morland B., French R., Flavell S. U. Effectiveness of combinations of bispecific antibodies for delivering saporin to human acute T-cell lymphoblastic leukaemia cell lines via CD7 and CD38 as cellular target molecules. Br J Cancer. 1992 Apr;65(4):545–551. doi: 10.1038/bjc.1992.112. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Ghetie V., Engert A., Schnell R., Vitetta E. S. The in vivo anti-tumor activity of immunotoxins containing two versus one deglycosylated ricin A chains. Cancer Lett. 1995 Nov 27;98(1):97–101. [PubMed] [Google Scholar]
  11. Ghetie V., Swindell E., Uhr J. W., Vitetta E. S. Purification and properties of immunotoxins containing one vs. two deglycosylated ricin A chains. J Immunol Methods. 1993 Nov 5;166(1):117–122. doi: 10.1016/0022-1759(93)90335-5. [DOI] [PubMed] [Google Scholar]
  12. Jansen B., Vallera D. A., Jaszcz W. B., Nguyen D., Kersey J. H. Successful treatment of human acute T-cell leukemia in SCID mice using the anti-CD7-deglycosylated ricin A-chain immunotoxin DA7. Cancer Res. 1992 Mar 1;52(5):1314–1321. [PubMed] [Google Scholar]
  13. Laemmli U. K. Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature. 1970 Aug 15;227(5259):680–685. doi: 10.1038/227680a0. [DOI] [PubMed] [Google Scholar]
  14. Lambert J. M., Senter P. D., Yau-Young A., Blättler W. A., Goldmacher V. S. Purified immunotoxins that are reactive with human lymphoid cells. Monoclonal antibodies conjugated to the ribosome-inactivating proteins gelonin and the pokeweed antiviral proteins. J Biol Chem. 1985 Oct 5;260(22):12035–12041. [PubMed] [Google Scholar]
  15. Marsh J. W., Neville D. M., Jr Kinetic comparison of ricin immunotoxins: biricin conjugate has potentiated cytotoxicity. Biochemistry. 1986 Jul 29;25(15):4461–4467. doi: 10.1021/bi00363a044. [DOI] [PubMed] [Google Scholar]
  16. May R. D., Wheeler H. T., Finkelman F. D., Uhr J. W., Vitetta E. S. Intracellular routing rather than cross-linking or rate of internalization determines the potency of immunotoxins directed against different epitopes of sIgD on murine B cells. Cell Immunol. 1991 Jul;135(2):490–500. doi: 10.1016/0008-8749(91)90292-j. [DOI] [PubMed] [Google Scholar]
  17. Morland B. J., Barley J., Boehm D., Flavell S. U., Ghaleb N., Kohler J. A., Okayama K., Wilkins B., Flavell D. J. Effectiveness of HB2 (anti-CD7)--saporin immunotoxin in an in vivo model of human T-cell leukaemia developed in severe combined immunodeficient mice. Br J Cancer. 1994 Feb;69(2):279–285. doi: 10.1038/bjc.1994.52. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Myers D. E., Yanishevski Y., Masson E., Irvin J. D., Evans W. E., Uckun F. M. Favorable pharmacodynamic features and superior anti-leukemic activity of B43 (anti-CD19) immunotoxins containing two pokeweed antiviral protein molecules covalently linked to each monoclonal antibody molecule. Leuk Lymphoma. 1995 Jun;18(1-2):93–102. doi: 10.3109/10428199509064928. [DOI] [PubMed] [Google Scholar]
  19. Preijers F. W., Tax W. J., De Witte T., Janssen A., vd Heijden H., Vidal H., Wessels J. M., Capel P. J. Relationship between internalization and cytotoxicity of ricin A-chain immunotoxins. Br J Haematol. 1988 Nov;70(3):289–294. doi: 10.1111/j.1365-2141.1988.tb02484.x. [DOI] [PubMed] [Google Scholar]
  20. Press O. W., Martin P. J., Thorpe P. E., Vitetta E. S. Ricin A-chain containing immunotoxins directed against different epitopes on the CD2 molecule differ in their ability to kill normal and malignant T cells. J Immunol. 1988 Dec 15;141(12):4410–4417. [PubMed] [Google Scholar]
  21. Stirpe F., Gasperi-Campani A., Barbieri L., Falasca A., Abbondanza A., Stevens W. A. Ribosome-inactivating proteins from the seeds of Saponaria officinalis L. (soapwort), of Agrostemma githago L. (corn cockle) and of Asparagus officinalis L. (asparagus), and from the latex of Hura crepitans L. (sandbox tree). Biochem J. 1983 Dec 15;216(3):617–625. doi: 10.1042/bj2160617. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Thorpe P. E., Brown A. N., Bremner J. A., Jr, Foxwell B. M., Stirpe F. An immunotoxin composed of monoclonal anti-Thy 1.1 antibody and a ribosome-inactivating protein from Saponaria officinalis: potent antitumor effects in vitro and in vivo. J Natl Cancer Inst. 1985 Jul;75(1):151–159. [PubMed] [Google Scholar]
  23. Vitetta E. S., Stone M., Amlot P., Fay J., May R., Till M., Newman J., Clark P., Collins R., Cunningham D. Phase I immunotoxin trial in patients with B-cell lymphoma. Cancer Res. 1991 Aug 1;51(15):4052–4058. [PubMed] [Google Scholar]
  24. Wargalla U. C., Reisfeld R. A. Rate of internalization of an immunotoxin correlates with cytotoxic activity against human tumor cells. Proc Natl Acad Sci U S A. 1989 Jul;86(13):5146–5150. doi: 10.1073/pnas.86.13.5146. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. van Oosterhout Y. V., van den Herik-Oudijk I. E., Wessels H. M., de Witte T., van de Winkel J. G., Preijers F. W. Effect of isotype on internalization and cytotoxicity of CD19-ricin A immunotoxins. Cancer Res. 1994 Jul 1;54(13):3527–3532. [PubMed] [Google Scholar]

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