Progress in Immunosuppressive Agents for Solid-Organ Transplantation

Toosendanin inhibits T-cell proliferation through the P38 MAPK signalling pathway

In recent years, immunosuppressants have shown significant success in the treatment of autoimmune diseases. Therefore, there is an urgent need to develop additional immunosuppressants that offer more options for patients. Toosendanin has been shown to have immunosuppressive activity in vitro as well as effects on autoimmune hepatitis (AIH) in vivo. Toosendanin did not induce apoptosis in activated T-cells and affect the survival rate of naive T-cells. Toosendanin did not affect the expression of CD25 or secretion of IL-2 by activated T-cells, and not affect the expression of IL-4 and INF-γ. Toosendanin did not affect the phosphorylation of STAT5, ERK, AKT, P70S6K. However, toosendanin inhibited proliferation of anti-CD3/anti-CD28 mAbs-activated T-cells with IC50 of (10 ± 2.02) nM. Toosendanin arrested the cell cycle in the G0/G1 phase, significantly inhibited IL-6 and IL-17A secretion, promoted IL-10 expression, and inhibited the P38 MAPK pathway. Finally, toosendanin significantly alleviated ConA-induced AIH in mice. In Summary, toosendanin exhibited immunosuppressive activity in vivo and in vitro. Toosendanin inhibits the proliferation of activated T-cells through the P38 MAPK signalling pathway, significantly suppresses the expression of inflammatory factors, enhances the expression of anti-inflammatory factors, and effectively alleviates ConA-induced AIH in mice, suggesting that toosendanin may be a lead compound for the development of novel immunomodulatory agents with improved efficacy and reduced toxicity.

A novel pectin polysaccharide from vinegar-baked Radix Bupleuri absorbed by microfold cells in the form of nanoparticles

Polysaccharides of vinegar-baked Radix Bupleuri (VBCP) have been reported to exhibit liver-targeting and immunomodulatory activities through oral administration, but the absorption behavior and mechanism of VBCPs have not been extensively studied. In this study, a novel HG type pectin polysaccharide, VBCP1-4, with a high molecular weight of 2.94 × 106 Da, was separated from VBCP. VBCP1-4 backbone was contained 1,4-α-D-GalpA, 1,4-α-D-GalpA6OMe, 1,3,4-α-D-GalpA and 1,2,4-α-D-Rhap. The branches were mainly contained 1,5-α-L-Araf, 1,3,5-α-L-Araf, t-α-L-Araf and t-α-D-Galp, which linked to the 3 position of 1,3,4-α-D-GalpA and the 4 position of 1,2,4-α-D-Rhap. VBCP1-4 could self-assemble to nanoparticles in water, with CMC values of 106.41 μg/mL, particle sizes of 178.20 ± 2.82 nm and zeta potentials of -23.19 ± 1.44 mV. The pharmacokinetic study of VBCP1-4, which detected by marking with FITC, revealed that it could be partially absorbed into the body through Peyer's patches of the ileum. In vitro absorption study demonstrated that VBCP1-4 was difficult to be absorbed by Caco-2 cell monolayer, but could be absorbed by M cells in a time and concentration dependent manner. The absorption mechanism was elucidated that VBCP1-4 entered M cells through clathrin-mediated endocytosis in the form of nanoparticles. These findings provide valuable insights into the absorption behavior of VBCP and contribute to its further development.

Immunosenescence as a reason of individualizing immunosuppressive therapy in kidney transplantation

Transplantation in elderly patients is obviously more challenging due to existing underlying diseases, changes in pharmacokinetics of immunosuppressive drugs, polypragmasy, and transformation of immunoreactivity (immunosenescence). Our review presents data on modification of adaptive and innate immunity during aging. It also considers the possibility of both reduced and adapted immunosuppressive therapy in elderly renal transplant recipients in achieving an optimal balance between efficacy and complications.

The effect of subsequent immunosuppressant use in organ-transplanted patients on prostate cancer incidence: a retrospective analysis using the Korean National Health Insurance Database

Backgrounds

Prostate cancer (PC) is the most common solid organ cancer. However, there is still no definite consensus before and after organ transplantation (TPL). We aimed to analyze whether PC incidence increased in TPL patients with subsequent use of immunosuppressants using the Korean National Health Insurance Database.

Methods

TPL patients between 2003 and 2015(N = 12,970) were age- and year-matched to non-TPL patients (N = 38,910) in a 1:3 ratio. Multivariate Cox regression analysis adjusted for significant prognostic clinicopathological parameters, including the duration of immunosuppressant agent use (0–300 or > 300 days), and Kaplan–Meier analysis with log-rank test were used to evaluate the association of TPL with PC incidence between the groups.

Results

Median overall survival was 4.86 years; overall mortality rate was 3.4% (n = 1761). Regardless of differences in baseline characteristics between the groups, multivariate analysis for PC incidence showed that age, immunosuppressant use, and TPL organ subtypes were significant factors for the overall population, whereas only age was significant in the TPL group (p < 0.05). After adjusting for age, underlying disease, and prescribed medication (aspirin, statin), multiple subgroup analysis models for PC incidence were evaluated. PC incidence was increased in the TPL group (hazard ratio [HR] 1.965, p < 0.001); however, PC incidence in the TPL group became insignificant after adjusting for immunosuppressant use (p = 0.194). Kaplan–Meier curves also showed that PC incidence was significantly different according to age and TPL with the use of immunosuppressants between the TPL and non-TPL groups.

Conclusions

PC incidence was higher in the TPL group using immunosuppressants than in the non-TPL group.

Trial registration: The study was retrospectively registered.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12894-021-00883-8.