Association of CD30 transcripts with Th1 responses and proinflammatory cytokines in patients with end-stage renal disease.

High serum sCD30 levels are associated with inflammatory disorders and poor outcome in renal transplantation. The contribution to these phenomena of transcripts and proteins related to CD30-activation and -cleavage is unknown. We assessed in peripheral blood of end-stage renal disease patients (ESRDP) transcripts of CD30-activation proteins CD30 and CD30L, CD30-cleavage proteins ADAM10 and ADAM17, and Th1- and Th2-type immunity-related factors t-bet and GATA3. Additionally, we evaluated the same transcripts and release of sCD30 and 32 cytokines after allogeneic and polyclonal T-cell activation. In peripheral blood, ESRDP showed increased levels of t-bet and GATA3 transcripts compared to healthy controls (HC) (both P<0.01) whereas levels of CD30, CD30L, ADAM10 and ADAM17 transcripts were similar. Polyclonal and allogeneic stimulation induced higher levels of CD30 transcripts in ESRDP than in HC (both P<0.001). Principal component analysis (PCA) in allogeneic cultures of ESRDP identified two correlation clusters, one consisting of sCD30, the Th-1 cytokine IFN-γ, MIP-1α, RANTES, sIL-2Rα, MIP-1ß, TNF-ß, MDC, GM-CSF and IL-5, and another one consisting of CD30 and t-bet transcripts, IL-13 and proinflammatory proteins IP-10, IL-8, IL-1Rα and MCP-1. Reflecting an activated immune state, ESRDP exhibited after allostimulation upregulation of CD30 transcripts in T cells, which was associated with Th1 and proinflammatory responses.

Release of soluble CD30 after allogeneic stimulation is mediated by memory T cells and regulated by IFN-γ and IL-2.

BACKGROUND: Membrane CD30 is an important costimulatory molecule for activated T lymphocytes, and serum level of soluble CD30 (sCD30) is considered a marker for predicting outcome in kidney transplantation. METHODS: We investigated the kinetics of CD30 expression on CD4 and CD8 T-cell populations and the source of sCD30 during alloimmune responses in vitro. The effect of neutralizing antibodies against interferon (IFN)-γ and other cytokines on sCD30 release and the involvement of metalloproteinases ADAM10 and ADAM17/TACE that are responsible for sCD30 shedding were also assessed. Memory phenotypes and CD30 expression on allostimulated CD3 lymphocytes were evaluated in dialysis patients and matched controls. RESULTS: Allogeneic stimulation resulted in conversion of naive responder cells to central memory CD4 cells (P<0.001 at 96 hr) and effector CD8 cells (P<0.01 at 120 hr), which was accompanied by increased CD30 expression. Release of sCD30 was attributed mainly to central memory cells, and neutralization of IFN-γ (P<0.001) and interleukin (IL)-2 (P<0.001) impaired the release of sCD30 during allostimulation but did not alter the levels of ADAM10 and ADAM17/TACE. CD30 expression was modulated in dialysis patients in a similar way as in healthy controls. CONCLUSIONS: Allostimulation results in the up-regulation of the T-cell activation marker CD30 on CD4 as well as CD8 memory T cells and increased release of sCD30 from these cells in an IFN-γ- and IL-2-dependent manner. These results may explain clinical findings on the suitability of sCD30 and IFN-γ- and IL-2-producing T cells for immune monitoring of kidney transplant recipients before and after transplantation.

Alloantigen-stimulated induction and release of CD30 in patients with end-stage renal failure.

High serum levels of soluble CD30 (sCD30) are associated with poor renal allograft survival, and regulatory T cells (Tregs) influence allograft survival depending on CD30 signaling. However, how sCD30 modulates alloimmune responses remains poorly understood. We measured the level of Tregs and sCD30 in patients with end-stage renal failure (ESRF) and analyzed whether allo- or polyclonal stimulation of the patients' T cells results in the expression and release of CD30. ESRF patients showed increased serum sCD30 levels and lower percentages of circulating Tregs as compared to healthy controls (HC) (p<0.001 and 0.024). Polyclonal and allogeneic stimulation resulted in higher expression of CD30, and after polyclonal stimulation, ESRF patients showed higher percentages of CD30-expressing T cells than HC (p<0.001). Compared to autologous stimulation, allogeneic stimulation induced significantly higher expression of CD30 on T cells of ESRF patients only. After polyclonal as well as allogeneic stimulation, an increased sCD30 content was found in culture supernatants of both ESRF patients and HC (p<0.001). Together with decreased Tregs, high serum sCD30 and increased induction of CD30 on T cells after polyclonal stimulation may explain exacerbated alloimmune responses and poor allograft survival in ESRF patients in whom immunosuppression is not able to control the alloimmune response.

Kidney graft recipients with pretransplantation HLA CLASS I antibodies and high soluble CD30 are at high risk for graft loss.

In the present study, we investigated whether pretransplantation HLA class I and class II antibodies and pretransplantation levels of soluble CD30 (sCD30) and IgA anti-Fab autoantibodies are predictive of kidney allograft survival. Pretransplantation sera of 504 deceased-donor kidney recipients were tested for IgG HLA class I and class II antibodies, sCD30, and IgA anti-Fab levels using the CTS 4 ELISA kit. Kidney graft survival was estimated by Kaplan-Meier method and multivariate Cox regression. Regardless of the presence of HLA class II antibodies, recipients with high HLA class I reactivity had lower 1-year graft survival than recipients with low reactivity (p < 0.01). Recipients with high sCD30 had lower 5-year graft survival rate than those with low sCD30 (p < 0.01). The sCD30 effect was observed in presensitized and nonsensitized recipients, demonstrated a synergistic effect with HLA class I antibodies (p < 0.001), and appeared to be neutralized in recipients with no HLA class II mismatches. IgA anti-Fab did not influence kidney graft survival. Our results indicate that high pretransplantation sCD30 levels and HLA class I positivity increase the risk of kidney graft loss regardless of other factors. Consequently, such determinations should be routinely performed to estimate recipients' risks of graft rejection before transplantation.

Evaluation of T-cell receptor repertoires in patients with long-term renal allograft survival.

The mechanisms underlying long-term acceptance of kidney allografts in humans under minimal or no maintenance immunosuppression are poorly understood. We analyzed the T-cell receptor (TCR) repertoires in circulating T cells of patients with long-term (> or = 9 years) renal allograft survival with (LTS-IS) and without immunosuppression (LTS-NoIS). T cells of LTS patients exhibited strongly altered TCR Vss usage, including an increased frequency of oligoclonality and a decreased frequency of polyclonality. All 3 LTS-NoIS and 12 of 16 LTS-IS patients demonstrated oligoclonality in at least three or more TCR V beta families, and the frequency of oligoclonality in these patients was significantly higher as compared to patients with well-functioning grafts at 3 years (p < 0.005 both), an uncomplicated course during the first year (p < 0.0001, both), acute rejection (p < 0.0001, both), chronic allograft nephropathy at 7 (p < 0.0001, both) or 13 years (p < 0.0001, both), dialysis patients (p < 0.0001, both) or healthy controls (p < 0.0001, both). In contrast to LTS patients, all other studied patient groups exhibited a polyclonal TCR repertoire. Our data indicate that TCR alteration is a common feature of long-term allograft outcome, which might be explained by clonal deletion, exhaustion of alloreactive T cells or predominant expression of particular T-cell subpopulations, such as regulatory T cells.