Engrafting Costimulator Molecules onto Tumor Cell Surfaces with Chelator Lipids: A Potentially Convenient Approach in Cancer Vaccine Development

Abstract

The genetic modification of cells to develop cell-based vaccines and to modulate immune responses in vivo can be risky and inconvenient to perform in clinical situations. A novel chelator lipid, nitrilotriacetic acid di-tetradecylamine (NTA-DTDA) that, via the NTA group has high affinity for 6His peptide, was used to directly anchor recombinant forms of T cell costimulatory molecules containing a C-terminal 6-His sequence onto tumor cell surfaces. Initial experiments using murine P815 tumor cells established the optimum conditions for incorporating NTA-DTDA onto the membranes of cells. P815 cells with incorporated NTA-DTDAbound hexahistidine-(6His)-tagged forms of the extracellular domains of murine B7.1 and CD40 (B7.1-6H and CD40-6H) at very high levels (fluorescence 200–300-fold above background), and both proteins could be anchored onto the cells simultaneously. Significant loss of the anchored or “engrafted” protein occurred through membrane internalization following culture of the cells under physiological conditions, but P815 cells with engrafted B7.1-6H and/or CD40-6H stimulated the proliferation of allogenic and syngeneic splenic T cells in vitro, and generated cytotoxic T cells when used as vaccines in syngeneic animals. Furthermore, the immunization of syngeneic mice with P815 cells engrafted with B7.1-6H or with B7.1-6H and CD40-6H induced protection against challenge with the native P815 tumor. The results indicate that the use of chelator lipids like NTD-DTDA to engraft costimulatory and/or other molecules onto cell membranes could provide a convenient alternative to transfection in the development of cell-based vaccines and for modulation of immune function.

Targeting Dendritic Cells with Antigen-Containing Liposomes

“…administration (18,20,33). The use of the chelator lipid NTA-DTDA to modify tumor cells and tumor cell-derived PMV for engraftment of T-cell costimulatory molecules has been described (31,34). We have produced recently a novel lipid, NTA 3 -DTDA (Fig.…”

Rapid Protein Anchoring into the Membranes of Mammalian Cells Using Oleyl Chain and Poly(ethylene glycol) Derivatives

“…In this experiment, BAM90-B or BAM90-F aqueous solutions were directly added to the cell suspension without preparation of liposomes for dissolving BAMs in either aqueous solution or culture medium. These experiments were conducted in serum-free medium, because preliminary experiments showed that serum albumin inhibited the anchoring of BAMs to the cell membrane, as reported previously in experiments using lipid anchors (16,18).…”

“…It has also been reported that some lipid anchors allow proteins to modify liposomes (10)(11)(12)(13). Furthermore, modification of the cell membrane has been accomplished by using lipid anchors, such as stearyl (2,14) and cholesterol (15) derivatives, glycosyl phosphatidyl inositol (GPI) anchor (16,17), and chelator lipid anchor, nitrilotriacetic acid ditetradecylamine (NTA-DTDA) (18)(19)(20). However, these lipid anchoring methods have some drawbacks.…”

Casual cell surface remodeling using biocompatible lipid‐poly(ethylene glycol)(n): Development of stealth cells and monitoring of cell membrane behavior in serum‐supplemented conditions

“…2 Similarly, van Broekhoven et al introduced poly(ethylene glycol)ylation [(PEG)ylation] to develop an antitumor cellular vaccine using chelate lipids. 3 Another example is the use of intelligent polymers to change cell surface characteristics in response to an environmental stimulus. 4 In addition to these approaches, studies using polymers have shown that the physical characteristics of the surface, such as the surface topography and chemical composition, can greatly affect how cells respond to another surface.…”