JOURNAL ARTICLE

In vitro and in vivo targeting of immunoliposomal doxorubicin to human B-cell lymphoma

D E Lopes de Menezes, L M Pilarski, T M Allen
Cancer Research 1998 August 1, 58 (15): 3320-30
9699662
The ability to selectively target liposomal anticancer drugs via specific ligands against antigens expressed on malignant cells could improve the therapeutic effectiveness of the liposomal preparations as well as reduce adverse side effects associated with chemotherapy. Long-circulating formulations of liposomes containing lipid derivatives of poly(ethyleneglycol) [sterically stabilized liposomes (SLs)] have been described previously, and new techniques have recently been developed for coupling monoclonal antibodies (Abs) at the poly(ethyleneglycol) terminus of these liposomes. Ab-targeted SLs [immunoliposomes (SILs)] containing entrapped anticancer drugs are predicted to be useful in the treatment of hematological malignancies such as B-cell lymphomas or multiple myeloma, in which the target cells are present in the vasculature. The specific binding, in vitro cytotoxicity, and in vivo antineoplastic activity of doxorubicin (DXR) encapsulated in SILs coupled to monoclonal Ab anti-CD19 (SIL[anti-CD19]) were investigated against malignant B cells expressing CD19 surface antigens. Binding experiments with SIL[anti-CD19] resulted in a 3-fold higher association of the SILs with a human CD19+ B lymphoma cell line (Namalwa) in comparison with nontargeted SLs. Using flow cytometry, fluorescently labeled SIL[anti-CD19] bound to B cells with no recognition of T cells in a mixture of B cells and T cells in culture. Nontargeted SLs demonstrated significantly lower recognition of either B cells or T cells. Targeted DXR-SIL[anti-CD19] displayed a higher cytotoxicity to B cells relative to DXR entrapped in nontargeted SLs. Therapeutic experiments in severe combined immunodeficient mice implanted with Namalwa cells by the i.v. or i.p. routes resulted in significantly increased effectiveness of DXR-SIL[anti-CD19] compared to similar amounts of free DXR, DXR-SL (no Ab), or isotype-matched nonspecific Abs attached to DXR-SL. Single doses (3 mg/kg) of DXR-SIL[anti-CD19] administered i.v. resulted in a significantly improved therapeutic benefit, including some long-term survivors. From our results, we infer that targeted anti-CD19 liposomes containing the anticancer drug DXR may be selectively cytotoxic for B cells and may be useful in the selective elimination of circulating malignant B cells in vivo.

Full Text Links

Find Full Text Links for this Article

Discussion

You are not logged in. Sign Up or Log In to join the discussion.

Trending Papers

Remove bar
Read by QxMD icon Read
9699662
×

Save your favorite articles in one place with a free QxMD account.

×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"