Homing of CD8CD57 T lymphocytes into acutely rejected renal allografts

Pre-transplant Th1 and post-transplant Th2 cytokine patterns are associated with early acute rejection in renal transplant recipients

In this retrospective study, we tried to define pre- and post-transplant immunological parameters that identify patients at risk for early acute rejection. Lymphocyte subpopulations and plasma levels of cytokines and neopterin were determined pre- and post-transplant in 32 renal transplant recipients with biopsy-proven early acute graft rejection. Recipients without early acute rejection served as controls. High pre-transplant interferon-gamma (IFN-gamma) plasma levels (p = 0.006), consistently high levels of neopterin early post-transplant (p = 0.008), a post-transplant switch from a Th1 to a Th2 cytokine pattern with decreasing IFN-gamma (p = 0.02), low CD8+ lymphocyte counts (p = 0.006) and consistently high CD19+ B lymphocyte counts were associated with acute rejection. Our data suggest that patients with a pre-transplant Th1 and an early post-transplant Th2 cytokine pattern are pre-disposed for early acute rejection.

The expression of integrins on activated T-cells in multiple sclerosis. Effect of intravenous methylprednisolone treatment

We studied the effect of intravenous methylprednisolone (MP) on the expression of the integrins, LFA-1 and VLA-4, on activated blood T-lymphocytes in 17 patients with relapses of clinically definite relapsing-remitting MS. MP treatment did not induce changes in the expression of CD3, CD4, DR, LFA-1 or VLA-4 markers when measured in the total population of lymphocytes in MS patients in relation to treatment. Treatment influenced neither the LFA-1 nor VLA-4 positive cells within the CD3+ population. MP treatment clearly decreased the DR+ CD3+ cells (P < 0.01) and the percentage of DR+ CD3+ lymphocytes bearing VLA-4 (P < 0.01). However, this was not the case when we studied the percentage of lymphocytes which expressed LFA-1. Glucocorticoids did not influence the mean intensity of the expression of the two integrins quantified in either total or DR+ CD3+ lymphocytes. Although, further research seems warranted to investigate a possible effect of MP on lymphocyte integrin function, this work corroborates the idea that MP treatment may interfere with the mechanisms of T-cell migration into CNS, thus modulating the activity of multiple sclerosis.

Pattern of cytokine expression in circulation CD57+ T cells from long-term renal allograft recipients

We made a quantitative analysis of the lymphokine mRNA and of proteins produced by CD57+ and CD57- circulating T cells isolated from long-term kidney-transplanted patients with expanded CD4+/CD57+ and CD8+/CD57+ T cells, and from normal individuals. We concentrated on IL-2 and IFN-gamma, which define a Th1-like type of lymphokine production, and on IL-4 which defines a Th-2-like type. We also analysed the production of IL-10 which is endowed with inhibitory effects on IL-2 and IFN-gamma synthesis, and of TNF-alpha, a pleiotropic inflammatory cytokine. On ionomycin + PMA stimulation, which reveals the intrinsic potential of lymphokine production by T cells, the CD57+ T cell subsets from all individuals produced high amounts of IFN-gamma and TNF-alpha mRNA and protein. They also produced IL-2, but to a much lesser extend than their CD57- counterparts, and little IL-4 and IL-10. They were no more capable of producing IL-2 when stimulated through the CD3/TCR in the presence of monocytes, yet still synthesized IFN-gamma. Our data suggest that the in vivo expansion of CD57+ T cells in stable allograft renal recipients might correspond to Th1 energized cells which on triggering of cell surface receptors hardly secrete lymphokines involved in cell cycle progression, but can still exert some effector functions, including IFN-gamma secretion.

Current status of immunological monitoring in the renal allograft recipient

With the appropriate combined use of different immune monitoring techniques, it is possible to derive sensitive diagnostic parameters for the transplant surgeon. However, the core biopsy or cytological examination of the graft continues to represent the gold standard for evaluating the specificity and sensitivity of these methods. With the development of newer monoclonal antibodies and a better understanding of the impact of immune processes on the behavior of various activation linked, T cell associated surface antigens, one may be able to secure further valuable information, with enhanced diagnostic and prognostic accuracy.