Delivery of Drugs in Temperature-Sensitive Liposomes

  • R. L. Magin
  • J. N. Weinstein
Part of the NATO Advanced Study Institutes Series book series (NSSA, volume 47)


In the presence of certain serum components, principally the lipoproteins, small unilamellar vesicles (SUV) can be made to release their contents rapidly and completely at the liquid crystalline phase transition temperature. By using a mixture of lipids with phase transition at about 42°C the SUV can be designed to release a drug preferentially in a capillary bed (for example, in a tumor) subjected to moderate local hyperthermia. We have made such “temperature-sensitive” liposomes from 7:1 to 7:3 (molar) mixtures of dipalmitoyl and distearoyl phosphatidylcholines and have characterized their interactions with serum components. All of the standard lipoprotein fractions promote release of contents at the transition, as does at least one non-lipoprotein component.

The SUV released essentially all of their contents of carboxyfluorescein dye during a single pass through a heated capillary bed in rat intestine. When injected i.v. in mice with subcutaneous L1210 tumors, they delivered 14 times as much 3H-methotrexate (MTX) to tumors heated to 42°C by water bath as compared to unheated tumors in the same animals. Inhibition studies with unlabelled MTX and with folinic acid indicated that the 3H-MTX had reached its site of action in the cell cytoplasm and that it had entered the cells by its normal transport mechanisms. Local heating did not increase accumulation of MTX in other parts of the body, suggesting that an increase in therapeutic index can be achieved with temperature-sensitive liposomes. Qualitatively similar results were obtained when subcutaneous Lewis lung tumors in the flanks of mice were heated with microwaves. Using therapeutic levels of liposomal MTX we obtained a 4- to 16-fold greater cell kill for the L1210 tumor than could be explained by the separate effects of heat and liposome-entrapped MTX.

Large multilamellar vesicles do not have characteristics appropriate for use as temperature-sensitive liposomes, but large uni-lamellar liposomes appear more favourable in that they can be made to release their contents (carboxyfluorescein, MTX, cytosine arabinoside) rapidly in the presence of serum. Because of their much larger ratio of internal volume to lipid, large unilamellar temperature-sensitive liposomes may prove especially useful in vivo.


High Density Lipoprotein Serum Component Small Unilamellar Vesicle Large Unilamellar Vesicle Local Hyperthermia 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Chabner, B.A. and Young, R.C., 1973, Threshold methotrexate concentration for in vivo inhibition of DNA synthesis in normal and tumorous target tissues, J. Clin. Invest. 52: 1804.PubMedCrossRefGoogle Scholar
  2. Cohen, C.M., Weissmann, G., Hoffstein, S., Awasthi, Y.C., Srivastava, S.K., 1976, Introduction to purified hexosaminidase A into TaySachs leucocytes by means of immunoglobulin-coated liposomes, Biochemistry 15: 452.PubMedCrossRefGoogle Scholar
  3. Gregoriadis, G. and Hunt, R., 1977, Fate of a liposome-associated agent injected into normal and tumour-bearing rodents, Attempts to improve localization in tumor tissues, Life Sci. 21: 357.PubMedCrossRefGoogle Scholar
  4. Gregoriadis, G. and Neerunjun, D.E., 1975, Homing of liposomes to target cells, Biochem. Biophys. Res. Commun. 65: 537.PubMedCrossRefGoogle Scholar
  5. Haest, C.M.W., de Gier, J.A., van Es, G.A., Verkleij, A.J. and van Deenan, L.L.M., 1972, Fragility of the permeability barrier of Escherichia coli, Biochim. Biophys. Acta 288: 43Google Scholar
  6. Hagins, W.A. and Yoshikami, S., 1977, Intracellular transmission of visual excitation in photoreceptors: Electrical effects of chelating agents introduced into rods by vesicle fusion, in: Vertebrate Photoreception, P. Fatt, H.B. Barlow, eds. Academic Press, New York.Google Scholar
  7. Hahn, G.M., 1978, Interactions of drugs and hyperthermia in vitro and in vivo., in: Cancer Treatment by Hypertheria and Radiation, C. Streffer, ed., Urban and Schwarzenberg, Baltimore.Google Scholar
  8. Har-Kedar, I. and Bleehen, N.M., 1976, Expereimental and clinical aspects of hyperthermia applied to the treatment of cancer with special reference to the role of ultrasonic and microwave heating, Adv. Radiat. Biol. 6: 229Google Scholar
  9. Juliano, R.L. and Stamp, D., 1976, Lectin-mediated attachment of glycoprotein-bearing liposomes to cells, Nature 261: 235PubMedCrossRefGoogle Scholar
  10. Klausner, R.D., Kumar, N., Weinstein, J.N., Blumenthal, R., and Flavin, M., 1981, Interaction of tubulin with phospholipid vesicles I: Association with vesicles at the phase transition, J. Biol. Chem., 256: 5879.PubMedGoogle Scholar
  11. Leserman, L.D., Weinstein, J.N., Blumenthal, R., Sharrow, S.O., and Terry, W.D., 1979, Binding of antigen-bearing fluorescent liposomes to the murine myeloma tumor MOPC 315, J. Immunol. 122: 585.PubMedGoogle Scholar
  12. Leserman, L.D., Barbet, J., Kourilsky, F.M., and Weinstein, J.N., 1980a, Liposomes directed to specific cellular targets by vocalently-coupled monoclonal antibody, protein A, and avidin, Nature 288: 602.PubMedCrossRefGoogle Scholar
  13. Leserman, L.D., Weinstein, J.M., Blumenthal, R., and Terry, W.D., 1980b, Receptor-mediated endocytosis of antibody-opsonized liposomes by tumor cells, Proc. Natl. Acad. Sci. 77: 4089.PubMedCrossRefGoogle Scholar
  14. Magee, W.E., Cronenberger, J.H. and Thor, D.E., 1978, Marked stimulation of lymphocyte-mediated attach on tumor cells by target-directed liposomes containing immune RNA, Cancer Res. 38: 1173.PubMedGoogle Scholar
  15. Magin, R.L., 1979, A microwave system for the controlled production of local tumor hyperthermia in animals, IEEE Trans. Microwave Theory Tech. 27: 78.CrossRefGoogle Scholar
  16. Magin, R.L. and Johnson, R.K., 1979, Effects of local tumor hyperthermia on the growth of solid mouse tumors, Cancer Res. 39: 4534.PubMedGoogle Scholar
  17. Schabel, F.M., 1977, Quantitative evaluation of anticancer agent activity in experimental animals, Pharmacology and Therapeutics (Part A) 1: 411.Google Scholar
  18. Scherphof, G., Morselt, H., Regts, J. and Wilschut, J.C., 1979, The involvement of the lipid phase transition in the plasma-induced dissolution of multilamellar phosphatidylcholine vesicles, Biochim. Biophys. Acta 56: 196.Google Scholar
  19. Streffer, C., 1978, “Cancer Therapy by Hyperthermia and Radiation”, Urban and Schwarzenberg, Baltimore.Google Scholar
  20. Suurkuusk, J., Lentz, B.R., Barenholz, Y., Biltonen, R.L., and Thompson, T.E., 1976, A calorimetric and fluorescent probe study of the gel-liquid crystalline phase transition in small single-lamellar dipalmitoylphosphatidylcholine vesicles, Biochemistry, 15: 1393.PubMedCrossRefGoogle Scholar
  21. Szoka, F., Jr., and Papahadjopoulos, D., 1978, Procedure for preparation of liposomes with large internal aqueous space and high capture by reverse-phase evaporation, Proc. Natl. Acad. Sci. USA. 75: 4194.PubMedCrossRefGoogle Scholar
  22. Weinstein, J.N. Blumenthal, R., Sharrow, S.O. and Henkart, P.A., 1978, Antibody-mediated targeting of liposomes: Binding to lymphocytes does not ensure incorporation of vesicle contents into the cells, Biochim. Biophys. Acta 509: 272.PubMedCrossRefGoogle Scholar
  23. Weinstein, J.N., Magin, R.L., Cysyk, R.L. and Zaharko, D.S., 1980, Treatment of solid L1210 murine tumors with local hyperthermia and temperature-sensitive liposomes containing methotrexate. Cancer Res. 40: 1388PubMedGoogle Scholar
  24. Weinstein, J.N., Magin, R.L., Yatvin, M.B., and Zaharko, D.S., 1979, Liposomes and local hyperthermia: Selective delivery of methotrexate to heated tumors, Science 204: 188.PubMedCrossRefGoogle Scholar
  25. Weinstein, J.N., Yoshikami, S., Henkart, P.A., Blumenthal, R. and Hagins, W.A., 1977, Liposome-cell interaction: Transfer and intracellular release of a trapped fluorescent marker, Science 195: 489.PubMedCrossRefGoogle Scholar
  26. Weinstein, J.N., Klausner, R.D., Innerarity, T.L., Ralston, E., and Blumenthal, R., 1981, “Phase transition release” (PTR), a new approach to the interaction of proteins with lipid vesicles: Application to lipoproteins, Biochim. Biophys. Acta, in press.Google Scholar
  27. Weissmann, G., Bloomgarden, D., Kaplan, R., Cohen, C., Hoffstein, S., Collins, T., Gotlieb, A. and Nagle, D., 1975, A general method for the introduction of enzymes, by means of immunoglobulincoated liposomes, into lysosomes of deficient cells, Proc. Natl. Acad. Sci. USA. 72: 88.PubMedCrossRefGoogle Scholar
  28. Yatvin, M.B., Weinstein, J.N., Dennis, W.H., and Blumenthal, R., 1978, Design of liposomes for enhanced local release of drags by hyperthermia, Science 202: 1290.PubMedCrossRefGoogle Scholar
  29. Yatvin, M.B., Kreutz, W., Florwitz, B.A. and Shinitzky, B., 1980, Ph-Sensitive liposomes: Possible clinical implications, Science 210: 1253.PubMedCrossRefGoogle Scholar
  30. Yatvin, M.B., Muhlensiepen, H., Porschen, W., Weinstein, J.N., and Feinendegen, L.E., 1981, Selective delivery of liposome encapsulated cis-dichlorodiammineplatinum (II) by heat: Influence on tumor drug uptake and growth, Cancer Res. 41: 1602PubMedGoogle Scholar
  31. Zaharko, D.S., Dedrick, R.L., Peale, A.L., Drake, J.C. and Lutz, R.J., 1974, Relative toxicity of methotrexate in several tissues of mice bearing Lewis lung carcinoma, JPET 189: 585.Google Scholar

Copyright information

© Plenum Press, New York 1982

Authors and Affiliations

  • R. L. Magin
    • 1
  • J. N. Weinstein
    • 2
  1. 1.Department of Electrical EngineeringUniversity of Illinois at Urbana-ChampaignUrbanaUSA
  2. 2.Section of Membrane Structure and Function Laboratory of Mathematical BiologyNational Cancer Institute, NIHBethesdaUSA

Personalised recommendations