ImmunoCellin : Antibody Intracellular Delivery Technology

Delivery of 1μg of IgG-DyLight in A549 cells

IgG-DyLight in A549 cells

“Antibodies are proteins that circulate in the blood, remaining outside the cells. In the case of cancers, though, over 90% of the deregulated targets that lead to the disease are inside the cells, Therapeutic antibody internalization offers huge potential by allowing to reach many new targets.”
Dr. Laurent Meunier, founder of BioCellChallenge

Without an appropriate transport mechanism, the antibodies are unable to cross the plasma membrane of living cells and reach their intracellular targets.

Features

ImmunoCellin is a lipid based technology that allow antibodies to be delivered directly in the cytosol of a living cell. Antibodies are integrated within lipidic structures through hydrophobic and electrostatic interactions. No chemical coupling occurs guaranteeing that the antibody is not denatured. It is delivered directly in the cytosol with no endosome trapping. The antibody keeps its full activity and can reach the intracellular target.

Reproducible and universal

The delivery has shown efficiency with a number of adherent cell lines.

Cos-7
Cos-7
NIH3T3
NIH3T3
3T6
3T6

The antibody keeps its full activity

A fluorescent antibody recognizing the NFkb protein, factor of transcription localized in the cytosol, has been internalized with the technology ImmunoCellin.

Anti-NFkB antibody
Anti-NFkB antibody

A signal was inducted (with PMA) at the level of the plasmic membrane in order to relocate the protein from the cytosol towards the nucleus. The protein was well located in the nucleus showing that the antibody was not denatured by IC and keeps it full activity.

Induction with PMA
Induction with PMA
anti-NFkB-3

The antibody can fix its target

A fluorescent antibody directed against a nucleoporin (protein located on the nuclear envelope) was internalized with ImmunoCellin. An intracellular marking has been clearly observed on the nuclear envelope. The antibody is not hindered inside the cell, it remains functional and keeps its ability to fix its target

The antibody is not hindered
inside the cell and can fix its target.
The antibody is not hindered inside the cell and can fix its target.
A fluorescent antibody directed against a nucleoprin was internalized with ImmunoCellin.
A fluorescent antibody directed against a nucleoprin was internalized with ImmunoCellin.

Internalization pathway : A direct delivery in the cytosol

In order to study the internalization,the complexe ImmunoCellin / Antiboby was compared with the transferrin, known for its endocytosis pathway.

An IgG , marked with green fluorescent labeling has been internalized with ImmunoCellin together with transferrin, labeling with red marker.

After 16 hours of incubation, we did not observe (colocalization) of the transferrin and the antibody internalized with IC . Both ways of internalization are different, what indicates that the endocytosis pathway of the antibody is not the one of the transferrin.

Biological activity of the internalized antibody in oncology

RAS, is an intracellular protein involved in the transduction of the signal. It comes to mute in numerous cancers occurring a constant and continuous cellular division.

An anti-RAS able to block this activity has been used and compared with an antibody control, able to recognize and fix the protein but devoided of RAS inhibitive activity.

The AC control had no effect and did not allow to inhibit the cellular proliferation. On the other hand, we clearly observed a reduction of the cellular proliferation on the tumoral cell lines 3T6 treated with the anti RAS IgG and internalized with ImmunoCellin.

The non proliferation effect is linked to the inhibition
of the activity of the protein RAS.
The non proliferation effect is linked to the inhibition of the activity of the protein RAS.