# Screening Oil Components for Interleukin-2-Loaded Lipid-Based Formulations with Molecular Dynamics, In Vitro Characterization, and Cell Culture Evaluation

## TL;DR

This study uses simulations and experiments to design a lipid-based formulation of IL-2 that enhances its cancer-fighting effects while reducing immune overactivation.

## Contribution

A novel lipid-based IL-2 formulation is proposed to modulate receptor interactions for improved antitumor efficacy.

## Key findings

- Molecular dynamics simulations identified excipients that protect IL-2 and reduce α-receptor interactions.
- In vitro tests showed the formulation preserves IL-2 activity and enhances anticancer effects on renal carcinoma cells.
- The formulation stabilizes IL-2 and supports its βγ-mediated antitumor mechanism.

## Abstract

Interleukin-2 (IL-2) is an immunostimulatory cytokine
that stimulates
T cells, natural killer cells, and other leukocytes, functioning as
a growth factor. IL-2 interacts with IL-2Rα, IL-2Rβ, and
γc receptors. IL-2 mediates its therapeutic effects
by interacting with the β and γ receptor subunits against
cancer, whereas interaction with the α, β, and γ
receptor complexes is critical for treating autoimmune disorders.
Current efforts aim to develop improved IL-2 biobetters that reduce
toxicity through lower dosing strategies, particularly by blocking
or slowing the interaction with IL-2Rα. According to these strategies,
this study aimed to design a lipid-based IL-2 formulation that could
modulate or partially prevent IL-2Rα binding, thereby enhancing
the βγ-mediated antitumor efficacy while minimizing α-associated
immune activation. Molecular dynamics (MD) simulates the physical
motions of atoms and molecules in large systems containing thousands
of atoms and is widely used in biotechnological drug formulations.
In this study, MD was used to simulate time-dependent interactions
between IL-2 and excipients of the lipid-based formulations to determine
suitable excipients. Desmond was used to simulate and observe the
temporal interactions between the formulation contents and IL-2. Interactions
with Arg38, Phe42, and Leu72key residues of the α-subunit
interfacewere specifically examined. According to the simulation
analyses, polar side chains were protected by lipids, while no incompatibility
was expected for the selected excipients. Interactions were observed
with Arg38, which interacts with IL-2Rα; thus, an enhanced antitumor
effect might be achieved. In addition to the in silico studies, in
vitro cell culture experiments were conducted to examine the biological
activity and anticancer efficacy of IL-2-loaded nanoemulsions. These
studies demonstrated that IL-2’s biological activity was preserved,
and its anticancer effect was enhanced against renal carcinoma cells.
Overall, the results suggest that the formulation stabilizes IL-2
and enhances its α-targeted antitumor mechanism through rational
excipient–protein interactions.