Pharmacology of immunosuppressive medications in solid organ transplantation

The effect of nurses' attitudes towards evidence-based nursing on the level of compliance with isolation measures in nurses caring for liver transplant patients

OBJECTIVE

Liver transplant recipients are at a high risk of infection during the first month. Therefore, it is crucial to implement isolation measures correctly to prevent the spread of nosocomial infections. Evidence-based practices and proper implementation of isolation measures can significantly reduce morbidity and mortality. The study aimed to investigate the impact of nurses' attitudes towards evidence-based nursing on their compliance with isolation measures.

METHODS

This is a descriptive study conducted between October 2023 and January 2024, with the participation of 137 nurses working in the organ transplant clinics of a university hospital in Turkey. Data was collected using a participant introduction form, the attitudes towards evidence-based nursing scale, and the compliance with isolation measures scale.

RESULTS

The mean total score for the scale of attitudes towards evidence-based nursing among nurses was 55.95 ± 10.43 (15-75). Similarly, the mean total score for the scale of compliance with isolation measures was 71.44 ± 13.53 (18-90). Both scores were above the middle level. The study found a moderately significant positive correlation between attitudes towards evidence-based nursing and compliance with isolation measures (r: 0.670, p: 0.000). The regression model showed that the attitude towards evidence-based nursing explained 44.9% of the positivity towards isolation measures (R2 = 0.449).

CONCLUSIONS

The study found a positive correlation between nurses' positive attitudes towards evidence-based nursing and their compliance with isolation precautions when caring for liver transplant patients. This highlights the significance of evidence-based nursing in patient care and the importance of adhering to isolation measures to prevent nosocomial infections.

Halofuginone Synergistically Enhances Anti-Proliferation of Rapamycin in T Cells and Reduces Cytotoxicity of Cyclosporine in Cultured Renal Tubular Epithelial Cells

Both rapamycin (RAPA) and cyclosporin A (CsA) are commonly used for immunosuppression, however their adverse side effects limit their application. Thus, it is of interest to develop novel means to enhance or preserve the immunosuppressive activity of RAPA or CsA while reducing their toxicity. Halofuginone (HF) has been recently tested as a potential immunosuppressant. This study investigated the interaction of HF with RAPA or with CsA in cell cultures. Cell proliferation in cultures was determined using methylthiazol tetrazolium assay, and cell apoptosis assessed by flow cytometric analysis and Western blot. The drug-drug interaction was determined according to Loewe’s equation or Bliss independence. Here, we showed that addition of HF to anti-CD 3 antibody-stimulated splenocyte cultures induced synergistic suppression of T cell proliferation in the presence of RAPA, indicated by an interaction index (γ) value of < 1.0 between HF and RAPA, but not in those with CsA. The synergistic interaction of RAPA with HF in the suppression of T cell proliferation was also seen in a mixed lymphocyte reaction and Jurkat T cell growth, and was positively correlated with an increase in cell apoptosis, but not with proline depletion. In cultured kidney tubular epithelial cells, HF attenuated the cytotoxicity of CsA. In conclusion, these data indicate that HF synergistically enhances anti-T cell proliferation of RAPA and reduces the nephrotoxicity of CsA in vitro, suggesting the potential use of HF for enhancing anti-T cell proliferation of RAPA and reducing CsA-mediated nephrotoxicity.

Tolerance induction by exosomes from immature dendritic cells and rapamycin in a mouse cardiac allograft model

Background

Dendritic cells (DCs) release bioactive exosomes that play an important role in immune regulation. Because they express low levels of class I major histocompatibility complex (MHC) and co-stimulatory molecules, exosomes derived from donor immature DCs (imDex) prolong allograft survival by inhibiting T-cell activation. However, this effect is limited and does not induce immunological tolerance when imDex are administered alone. Thus, we tested the effect of combined treatment with donor imDex and low-dose rapamycin on inducing tolerance in a mouse cardiac transplantation model.

Methods

ImDex were obtained from the culture supernatant of immature DCs derived from donor mouse (C57BL/6) bone marrow and were injected with suboptimal doses of rapamycin into recipient mouse (BALB/c) before and after transplantation. The capacity of this treatment to induce immune tolerance was analyzed in vitro and in vivo using the mouse cardiac transplantation model.

Results

Donor imDex expressed moderate levels of MHC class II and low levels of MHC class I and co-stimulatory molecules, but neither imDex nor subtherapeutic rapamycin dose alone induced cardiac allograft tolerance. Combined treatment with imDex and rapamycin, however, led to donor specific cardiac allograft tolerance. This effect was accompanied by decreased anti-donor antigen cellular response and an increased percentage of spleen CD4⁺CD25⁺ T cells in recipients. Furthermore, this donor specific tolerance could be further transferred to naïve allograft recipients through injection of splenocytes, but not serum, from tolerant recipients.

Conclusion

Combined with immunosuppressive treatment, donor imDex can prolong cardiac allograft survival and induce donor specific allograft tolerance.