Sirolimus‐ and cyclosporine‐loaded nanostructured lipid carriers: Development, characterization, and in vitro evaluation in T‐cell profiles of patients with a history of recurrent pregnancy loss

Purpose The authors developed nanostructured lipid carriers (NLCs) loaded with sirolimus (SRL) and cyclosporine (CsA) to improve their therapeutic efficacy in recurrent pregnancy loss (RPL) patients. Methods Mono‐delivery and co‐delivery of SRL and CsA by NLCs (S‐NLCs, C‐NLCs, and S‐C‐NLCs) were developed. The MTT assay was used to study the optimum dose of formulations. PCR, Western blotting, and ELISA were also conducted. Results Well‐designed nanodrugs with a suitable size, zeta potential, desirable encapsulation efficiency drug loading, and cellular uptake confirmed optimum formulations. Based on cell viability, the amounts of SRL and CsA could be reduced greatly due to the co‐delivery by NLCs. Following S‐NLCs and C‐NLCs interventions in T cells of patients with RPL and immune abnormality, a significant difference was observed in transcription factors and cytokine levels of Th1, Th17, and Tregs compared with healthy samples. Thus, a higher level of pro‐inflammatory cytokines (IFN‐γ, TNF‐α, IL‐17, and IL‐21) and their regulators (T‐bet and RORγt), as well as a lower level of an anti‐inflammatory cytokine (IL‐10) and its regulatory (Foxp3), were observed. However, no significant difference was found following the S‐C‐NLCs intervention. Conclusions S‐C‐NLCs effectively balance the immune responses in peripheral T cells in RPL patients to induce maternal immune tolerance. Immune abnormalities play a major role in the pathogenesis of RPL by impairing maternal‐fetal immune tolerance. The use of nanolipid carriers (NLCs) can improve the therapeutic efficacy of immunosuppressive drugs, meanwhile decreasing side effects. Co‐delivery of SRL and CsA by NLCs can be effectively modified maternal immune responses in RPL patients.