– OF-Deg-Lin is a biodegradable lipid containing an ester group, developed from the nonbiodegradable, linoleic acid derived OF-02; mRNA-LNPs containing OF-Deg-Lin showed high expression in the spleen. The ionizable lipid Of-Deg-Lin was synthesized,
which possessed the similar chemical structure with OF-02.Both Of-Deg-Lin and OF-02 had diketopiperazine core and
doubly unsaturated tails, and the difference between them
was that Of-02 contained nondegradable 1,2-amino-alcohol linkages,
whereas Of-Deg-Lin contained degradable ester linkages The change of linker altered iLNPs distribution
and mRNA expression in vivo. Although the Of-Deg-Lin iLNPs
could accumulate in the liver and spleen, they induced the
expression of most functional proteins in B lymphocytes of
spleen (over 85% of the total protein), not in the liver.
Of-Deg-Lin iLNPs can deliver mRNA and express functional
proteins in the spleen specifically, but the mechanism
is unclear.