Association of Serum MiR-142-3p and MiR-101-3p Levels with Acute Cellular Rejection after Heart Transplantation

Abstract

Background: Identifying non-invasive and reliable blood-derived biomarkers for early detection of acute cellular rejection in heart transplant recipients is of great importance in clinical practice. MicroRNAs are small molecules found to be stable in serum and their expression patterns reflect both physiological and underlying pathological conditions in human.

Methods: We compared a group of heart transplant recipients with histologically-verified acute cellular rejection (ACR, n = 26) with a control group of heart transplant recipients without allograft rejection (NR, n = 37) by assessing the levels of a select set of microRNAs in serum specimens.

Results: The levels of seven microRNAs, miR-142-3p, miR-101-3p, miR-424-5p, miR-27a-3p, miR-144-3p, miR-339-3p and miR-326 were significantly higher in ACR group compared to the control group and could discriminate between patients with and without allograft rejection. MiR-142-3p and miR-101-3p had the best diagnostic test performance among the microRNAs tested. Serum levels of miR-142-3p and miR-101-3p were independent of calcineurin inhibitor levels, as measured by tacrolimus and cyclosporin; kidney function, as measured by creatinine level, and general inflammation state, as measured by CRP level.

Conclusion: This study demonstrated two microRNAs, miR-142-3p and miR-101-3p, that could be relevant as non-invasive diagnostic tools for identifying heart transplant patients with acute cellular rejection.

Conflict of interest statement

The authors have declared that no competing interests exist.

Figures

Fig 1. Serum levels of microRNAs in heart transplant patients.

The levels of seven microRNAs were significantly higher in heart transplant patients with allograft rejection (ACR, n = 26) compared to the patients without rejection (NR, n = 37). Data is shown as mean ± SEM. Statistical analysis was performed with Student’s t-test. *P<0.05; **P<0.01.

Fig 2. Receiver Operator Characteristic (ROC) analysis.

Patients with and without acute cellular rejection could be discriminated by miR-142-3p (AUC = 0.78, CI95% = 0.67 to 0.89), miR-101-3p (AUC = 0.75, CI95% = 0.62 to 0.87), miR-424-5p (AUC = 0.73, CI95% = 0.60 to 0.86), miR-27a-3p (AUC = 0.72, CI95% = 0.59 to 0.85), miR-339-3p (AUC = 0.71, CI95% = 0.57 to 0.84), miR-144-3p (AUC = 0.70, CI95% = 0.56 to 0.83) and miR-326 (AUC = 0.69, CI95% = 0.56 to 0.82).

Fig 3. MicroRNA fold change in serum sample of heart transplant patients reported by time post-transplantation.

A) MiR-142-3p fold change and B) MiR-101-3p fold change (≤1 month, n = 14(NR) and n = 13(ACR); >1–3 months, n = 13(NR) and n = 6(ACR); >3–6 months, n = 7(NR) and n = 4(ACR); >6–12 months, n = 3(NR) and n = 3(ACR). All data are mean ±SEM, Student’s t-test, **p<0.01).

Fig 4. CRP level and microRNAs fold change in heart transplant patients.

(A) There is no significant difference between mean CRP level in acute cellular rejection group (n = 4) compared to the non-rejection group (n = 7) of heart transplant patients (NR = 32.2 mg/L vs. ACR = 3.5 mg/L, p = 0.1) and (B) There is no correlation between CRP level in heart transplant patients and miR-142-3p fold change (n = 11; R2 = 0.06 and P = 0.47) or miR-101-3p fold change (n = 11; R2 = 0.01 and P = 0.75).

Fig 5. Calcineurin inhibitor levels and microRNA fold change in heart transplant patients.

(A) There is no significant difference between mean tacrolimus level in acute cellular rejection group (n = 5) compared to the non-rejection group (n = 24) of heart transplant patients (NR = 12.9 ug/L vs. ACR = 10.4 ug/L, p = 0.4) and (B) There are no correlations between miR-142-3p fold change and tacrolimus (n = 29; R2 = 0.05; p = 0.25) or cyclosporin (n = 6; R2 = 0.07; p = 0.61) and there are no correlations between miR-101-3p fold change and tacrolimus (n = 29; R2 = 0.01; p = 0.10) or cyclosporine (n = 6; R2 = 0.05; p = 0.68).

Fig 6. Creatinine level and microRNAs fold change in heart transplant patients.

(A) There is no significant difference between mean creatinine level in ACR group (n = 26) vs. NR group (n = 37) in heart transplant patients (NR = 133.2 umol/L vs. ACR = 105.7 umol/L, p = 0.055). (B) There is no correlation between creatinine levels and miR-142-3p (R2 = 0.02, p = 0.24) or miR-101-3p (R2 = 0.06, p = 0.06) in heart transplant patients.