Mistletoe lectin

Sweeney, Edel C., Alexander G. Tonevitsky, Rex A. Palmer, Hidie Niwa, Uwe Pfueller, Juergen Eck, Hans Lentzen, Igor I. Agapov, and Mikhail P. Kirpichnikov. "Mistletoe Lectin I Forms a Double Trefoil Structure." FEBS Letters 431 (1998) 367-70. 

B17. Bussing, A., Vervecken, W, Wagner, M., Wagner, B., Pfuller, U., and Schietzel, M., Expression of mitochondrial Apo2.7 molecules and caspase-3 activation in human lymphocytes treated with the ribosome-inhibiting mistletoe lectins and the cell membrane permeabilizing viscotoxins. Cytometry 37, 133-139 (1999). 

Recombinant mistletoe-lectin 1999 C Factor 1000 (rML IPCR 200 fg/ml Niemeyer et al. [26], purified aggregates... 

Pharmacotoxic and pharmacokinetic studies carried out for the new antitumor drug Aviscumine (rViscumin) were supported by a robust quantitative IPCR assay developed by Adler et al. [66, 85], The potency of this protein-based drug, derived from recombinant mistletoe lectine, required initial doses well below the quantification range accessible by conventional ELISA. An IPCR assay was adapted and validated for the quantification of rViscumin in standardized human serum [66, 85, 86] and subsequently... 

A 73-year-old man with a 5-year history of centrocytic non-Hodgkin s lymphoma presented with subcutaneous nodules in the abdominal wall at the sites where he had previously received subcutaneous injections of mistletoe (6). The nodules turned out to be infiltrations by the centrocytic lymphoma. The patient died 6 weeks later of bilateral pneumonia. The authors hypothesized that mistletoe has a growth-promoting action on lymphoma cells, mediated by high local concentrations of mterleukin-6 liberated from the skin by mistletoe lectins. 

Bussing, A., Suzart, K., Bergmann, J., Pfuller, U., Schietzel, M. and Schweizer, K. (1996) Induction of apoptosis in human lymphocytes treated with Viscum album L. is mediated by the mistletoe lectins. Cancer Lett, 99, 59-72. 

Franz, H. (1986) Mistletoe lectins and their A and B chains. Oncology, 43 Suppl 1, 23-34. 

Krauspenhaar, R., Eschenburg, S., Perbandt, M., Kornilov, V., Konareva, N., Mikailova, L, Stoeva, S., Wacker, R., Maier, T., Singh, T., Mikhailov, A., Voelter, W. and Betzel, C. (1999) Crystal structure of mistletoe lectin I from Viscum album. Biochem Biophys Res Commun, 257, 418 24. 

I-anger, M., Mockel, B., Eck, J., Zinke, H. and Lentzen, H. (1999) Site-specific mutagenesis of mistletoe lectin the role of RIP activity in apoptosis. Biochem Biophys Res Commun, 264, 944—948. 

Vervecken, W., Kleff, S., Pfuller, U. and Bussing, A. (2000) Induction of apoptosis by mistletoe lectin I and its subunits. No evidence for cytotoxic effects caused by isolated A- and B-chains. Int J Biochem Cell Biol, 32, 317-326. 

The mistletoe lectins (m.w. 60-120,000) have, in very low doses, an immunostimulating effect. The F-lymphocyte stimulant effect of several plant lectins is known. 

Kunze E, Schulz H, Gabius HJ. Inability of galactoside-specific mistletoe lectin to inhibit N-methyl-N-nitrosurea-induced tumor development in the urinary bladder of rats and to mediate a local cellular immune response after long-term administration. J Cancer Res Clin Oncol 1998 124(2) 73-87. 

S. Stoeva, M. Franz, R. Wacker, R. Krauspenhaar, E. Guthohrlein, A. Mikhailov, C. Betzel, and W. Voelter, Primary structure, isoforms, and molecular modeling of a chitin-binding mistletoe lectin. Arch. Biochem. Biophys., 392 (2001) 23-31. 

The mistletoe lectins inhibited the growth of multidrug-resistant human colon cancer line HT 29 (mdr) in vitro Numerous studies have reported immunostimulatoiy and proapoptotic effects for mistletoe extracts, preparations, and components. The mistletoe extracts and preparations also significantly inhibited carcinogenesis and metastatis. Animal studies have shown that mistletoe preparations suppressed side effects when used as an adjunct to chemotherapy and radiation therapy. ... 

Btissing, A. 1996. Induction of apoptosis by the mistletoe lectins A review on the mechanisms of cytotoxicity mediated by Viscum album L. Apoptosis l(l) 25-32. 

Mistletoe lectins as immunostimulants (chemistry, pharmacology and clinic)... 

Table 1 - Biochemical properties of the different mistletoe lectins ...

Mistletoe lectins have been extensively analyzed for their primary structure. Only the complete amino acid sequence of the A chain of mistletoe lectin 1 (VAA-1) has been determined thus far [25] but the data show a great homology with other ribosome inactivating proteins such as abrin a or ricin D with 111 and 103 amino acid residues conserved, respectively. 

Inflammatory processes after mistletoe lectin or extract application and the cytokine release... 

To circumvent the drawbacks of different preparations from plant material, recombinant mistletoe lectin might be the substance of choice. It can be prepared in large quantities of equal quality.The research of the recombinant form of VAA-1 may also give new clinical perspectives. Recent in vitro investigations with recombinant lectin revealed NK stimulatory effects in synergism with IL-2 and IL-12. Similar to plant lectin in animal models, recombinant VAA-1 was also able to stimulate the NK cell-mediated cytotoxic activity of splenocytes Nat 1mm in press Fig. 4). 

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