This is a non-interventional cohort study to assess a novel assay to detect excessive or insufficient immunosuppression from the drug tacrolimus in lung transplant recipients. The assay measures mean residual expression (MRE) of genes downstream of nuclear factor of activated T cells (NFAT), a transcription factor regulated by tacrolimus. The investigators will assess whether MRE levels identify subjects at risk for rejection (insufficient immunosuppression) or infection (excessive immunosuppression).
Study Type
OBSERVATIONAL
Enrollment
50
University of California
San Francisco, California, United States
Association of Percentage of Mean Residual Expression (MRE%) of NFAT-related Cytokine Expression and Acute Cellular Rejection
The prescribed tacrolimus dosage was determined by the treating physician who was not aware of the study-assay values. For the study assay, two blood draws were collected at a study visit during the assessment period (from 1 month up to 18 months post-transplant). The first draw occurred before tacrolimus dosage (trough) and the second occurred 90 to 120 minutes after tacrolimus dosage (peak). To determine MRE, whole blood was stimulated, RNA was extracted, and residual expression of NFAT-related cytokines (NFAT: nuclear factor of activated T-cells) was determined by quantitative polymerase chain reaction (qPCR). Researchers stratified blood draws based on subject's rejection pathology at time of blood draw and observed percentage distribution of MRE values within each rejection pathology group. Observed differences between MRE distributions within non-rejection group and rejection groups.
Time frame: from 1 month up to 18 months post-transplant
Association of Percentage of Mean Residual Expression (MRE%) of NFAT-related Cytokine Expression and Infection
Researchers stratified blood draws based on subject's airway infection status at time of blood draw (based on biopsy results) and observed percentage distribution of MRE values within each infection status group. Researchers observed differences between MRE distributions within subjects with airway infection at time of blood draw and subjects with no infection diagnosis.
Time frame: from 1 month up to 18 months post-transplant
Association of Percentage of Mean Residual Expression (MRE%) of NFAT-related Cytokine Expression and Weeks Post-Transplant
Researchers observed percentage distribution of MRE values at time of blood draw from study visits at 4 weeks post-transplant up to 82 weeks post-transplant. Researchers observed association between percentage of MRE at time of blood draw and the number of weeks post-transplant.
Time frame: from 1 month (4 weeks) up to 18 months (82 weeks) post-transplant
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.
Association of Percentage of Mean Residual Expression (MRE%) of NFAT-related Cytokine Expression and Tacrolimus Trough Level
Researchers observed percentage distribution of MRE values on the day of blood draws. Researchers measured tacrolimus concentration in blood drawn before tacrolimus dosage (trough) and observed the association between percentage of MRE on the day of blood draw and tacrolimus trough level.
Time frame: from 1 month up to 18 months post-transplant
Association of Percentage of Mean Residual Expression (MRE%) of NFAT-related Cytokine Expression and Medication Dosages
Researchers observed percentage distribution of MRE values on the day of blood draws and measured tacrolimus, prednisone, and mycophenolate dose at the time of blood draw. Researchers observed the association between percentage of MRE on the day of blood draw and tacrolimus, prednisone, and mycophenolate dose, respectively, at the time of blood draw.
Time frame: from 1 month up to 18 months post-transplant