Transport of Surface Engineered Polyamidoamine (PAMAM) Dendrimers Across IPEC-J2 Cell Monolayers

Abstract

The aim of our study was to prepare arginine-and ornithineconjugated Polyamidoamine (PAMAM) dendrimers and study their permeability across IPEC-J2 cell monolayers, a new intestinal cell line model for drug absorption studies. Arginine and ornithine were conjugated to the amine terminals of the PAMAM G4 dendrimers by Fmoc synthesis. The apical-to-basolateral (AB) and basolateral-to-apical (BA) apparent permeability coefficients (P app ) for the PAMAM dendrimers increased by conjugating the dendrimers with both of these polyamines. The enhancement in permeability was dependent on the dendrimer concentration and duration of incubation. Correlation between monolayer permeability and the decrease in transepithelial electrical resistance (TEER) with the PAMAM dendrimers and the polyamine-conjugated dendrimers suggests that paracellular transport is one of the mechanisms of transport across the epithelial cells. Cytotoxicity of these surface-modified dendrimers was evaluated in IPEC-J2 cells by MTT (methylthiazoletetrazolium) assay. Arginine-conjugated dendrimers were insignificantly more toxic than PAMAM dendrimer as well as ornithine-conjugated dendrimers. Though investigations on the possible involvement of other transport mechanisms are in progress, results of the present study suggest the potential of dendrimer-polyamine conjugates as the carriers for antigen/drug delivery through the oral mucosa.

Poly(amido amine) dendrimers in oral delivery

“…54,55 In both cell lines, there was no significant difference in cytotoxicity between polyamine-conjugated dendrimer and native dendrimers. Furthermore, a concentration and timedependent enhancement in permeability was observed from apical to the basolateral side for the polyamine conjugated PAMAM dendrimers.…”

“…Furthermore, a concentration and timedependent enhancement in permeability was observed from apical to the basolateral side for the polyamine conjugated PAMAM dendrimers. 54,55 Another proven strategy to improve biocompatibility and pharmacokinetics of polymeric drug carriers in vivo is PEGylation. PEGylation of anionic dendrimers G3.5-COOH and G4.5-COOH with PEG 750 kDa did not significantly alter cytotoxicity up to a concentration of 0.1 mM.…”

The IPEC-J2 Cell Line

“…A drug transport permeability study showed that IPEC-J2 cells form a tighter monolayer compared to Caco-2 cells (Pisal et al 2008 ). On the other hand, Caco-2 and T84 cells produce a more pronounced mucus layer compared to IPEC-J2 cells (Navabi et al 2013 ).…”

Eleutheroside B increase tight junction proteins and anti‐inflammatory cytokines expression in intestinal porcine jejunum epithelial cells (IPEC‐J2)

“…The intestinal epithelium of pigs performs a critical role in nutrient absorption and serves as a barrier, limiting the permeability of toxic substances (Zhao et al, ). In addition, the epithelial cell barrier protects the mucous membrane of the gastrointestinal tract (Pisal, Yellepeddi, Kumar, & Palakurthi, ). The tight intracellular junction proteins lie between the epithelial cells, which restrict the absorption of drugs and prevent the flow of possible antigens and pathogens from the lumen to the sub‐mucosa (De Magistris, ; Pisal et al, ).…”