Tapering immunosuppressive therapy significantly improves in vivo cutaneous delayed type hypersensitivity responses.

Immunosuppressive therapy affects cell-mediated immunity and thereby increases the frequency of infections and malignancies in transplanted patients. We questioned whether reducing the immunosuppressive dose in stable kidney transplant patients has an in vivo effect on cutaneous delayed type hypersensitivity responses (DTH) reflecting cell-mediated immunity. We measured DTH responses to recall antigens (Tetanus, Diphteria, Streptococcus, Tuberculin, Candida, Trychophyton, Proteus, glycerin control) on the volar surface of the forearm in patients before and after successful reduction (50%) of the dose of mycophenolate mofetil (MMF) or azathioprine (AZA).

Calcineurin inhibitor withdrawal in stable kidney transplant patients decreases the donor-specific cytotoxic T lymphocyte precursor frequency.

Background: In a prospective study, calcineurin inhibitors (CNI) were withdrawn in patients two years after kidney transplantation. We questioned whether stopping CNI had an effect on the donor-specific reactivity, as CNI might hinder immune responses leading to graft acceptance.

Methods: We measured the donor-specific cytotoxic T lymphocyte (CTL) precursor frequency (CTLpf) in 54 patients before and after withdrawal of CNI.

Reduction of immunosuppressive load in renal transplant recipients with a low donor-specific cytotoxic T-lymphocyte precursor frequency is safe.

Background: Tapering of immunosuppressive medication is indicated to prevent long-term side effects. Recently, we have shown that renal transplant recipients can safely be converted from calcineurin inhibitors to MMF or AZA when their donor-specific cytotoxic T-lymphocyte precursor frequencies (CTLpf) are below 10/10(6) PBMC. We wondered whether a low CTLpf also had predictive value when immunosuppressive medication was reduced in patients only on MMF or AZA and steroid medication.

Tapering immunosuppression in recipients of living donor kidney transplants.

We have previously suggested that the in vitro donor-specific cytotoxic T-lymphocyte precursor (CTLp) assay can guide us to identify patients in which the immunosuppressive load can be tapered. In a clinical trial we had observed that a low (<10/10(6) PBMC) frequency of these CTLp was predictive for an uneventful rejection-free clinical course in patients that were converted from calcineurin inhibitors to mycophenolate mofetil or azathiopine. In the present prospective study in 81 stable kidney transplant recipients, already converted from calcineurin inhibitors, we measured CTLp frequencies and reduced the immunosuppressive load on a routine basis when CTLp were <10/10(6) PBMC.

Proteinuria after renal transplantation affects not only graft survival but also patient survival.

Background: Proteinuria is associated with an increased risk of renal failure. Moreover, proteinuria is associated with an increased death risk in patients with diabetes mellitus or hypertension and even in the general population.

Methods: One year after renal transplantation, we studied the influence of the presence of proteinuria on the risk of either graft failure or death in all 722 recipients of a kidney graft in our center who survived at least 1 year with a functioning graft.