Balance of transforming growth factor-beta1 and platelet-derived growth factor-BB is associated with kidney allograft rejection.

BACKGROUND: About 50% of kidney-transplant patients undergo organ rejection within 10 years. Chronic allograft nephropathy (CAN) represents the dominant cause of kidney transplant failure and accounts for 50-80% of graft loss in long-term surviving patients. CAN pathogenesis is multifactorial and not-completely elucidated; several reports indicate TGF-beta1 and platelet-derived growth factor (PDGF)-BB expression in CAN suggesting a possible role of these factors in the allograft arteriosclerosis and graft failure. METHODS: We investigated the plasma expression concentrations of human growth factors with enzyme-linked immunosorbent assays and appropriate statistical analysis. RESULTS: We present evidences showing statistically significant association of CAN with a specific balance between TGF Beat1 and PDGF-BB plasma concentrations, in 129 kidney-transplant patients and 15 healthy controls. Odds ratios were computed to correlate expression-levels with CAN occurrence. CONCLUSION: We believe these data may suggest a novel non-invasive method to identify early molecular markers of graft deterioration.

[Kidney transplant and cancer risk: an epidemiological study in Northern and Central Italy]. / Trapianto di rene e rischio di cancro: studio epidemiologico in Nord e Centro Italia.

OBJECTIVE: This investigation aimed at highlighting the cancer risk of recipients of kidney transplant in northern and central Italy. METHODS: Data on 2,120 kidney transplant recipients from Niguarda Ca' Granda Hospital Milan, or from Policlinico "A. Gemelli", Rome, were analyzed The period at risk of developing cancer (person-years, PY) was computed from 30 days after transplant to date of cancer diagnosis, or date of death, or date of re-entering dialysis, or date of last follow-up. Observed and expected numbers of cancer were compared through sex- and age-standardized incidence ratios (SIRs) and 95% confidence intervals (CIs). The transplant attributable fraction (AF) of cancer cases and incidence rate ratios (IRR) were also computed. RESULTS: After 16.594 PY of follow-up (median flow-up: 6.8 years), 121 cancer cases were diagnosed (729.2 cases/10(5) PY). The SIR for all cancers was 1.9. Kaposi's sarcoma (KS) (27 cases observed, SIR = 82) and non-Hodgkins lymphoma (NHL) (18 cases observed a SIR = 6.4 were the most common cancers. Significantly increased SIRs were also noted for native kidney (11 cases observed SIR = 4.9), corpus uteri (6 cases observed SIR = 4.6), and liver (6 cases observed, SIR = 3.1). The transplant AF was 46.9%, largely due to KS (98.8%) and NHL (84.3%). Since SIRs decreased with increasing age, the transplant AF ranged from 73.2% below 45 years of age to 30.4% after 54. Among risk factors, area of birth strongly influenced the risk of KS, with a 3-fold higher risk in those born in the South of Italy as compared to those born in the northern part. CONCLUSIONS: Immune depression after kidney transplantation entails a two-fold increased overall risk of cancer, mainly related to cancers associated to a viral aetiology. Furthermore, our findings suggest the need to adopt a specific serological screening for the prevention of post-transplant KS in individuals born in southern Italy.

Risk of cancer following immunosuppression in organ transplant recipients and in HIV-positive individuals in southern Europe.

This investigation highlighted the risk of cancer in 8074 HIV-infected people and in 2875 transplant recipients in Italy and France. Observed and expected numbers of cancer were compared through sex- and age-standardised incidence ratios (SIRs) and 95% confidence intervals (CIs). After 15 years of follow-up, the cumulative probability of cancer was 14.7% in transplant recipients and 13.3% in HIV-positives. The SIRs for all cancers were 9.8 in HIV-positives and 2.2 in transplants. Kaposi's sarcoma (SIR=451 in HIV-positives, 125 in transplants) and non-Hodgkin lymphoma (SIR=62 and 11.1, respectively) were the most common cancers. A significantly increased SIR for liver cancer also emerged in both groups. The risk of lung cancer was significantly elevated in heart transplant recipients (SIR=2.8), and of borderline statistical significance in HIV-positive people (95% CI:0.9-2.8). Immune depression entails a two-fold increased overall risk of cancers, mainly related to cancers associated with a viral aetiology.

Metallic but not ceramic wear particles increase prostaglandin E2 release and interleukin-1beta gene expression in human blood monocytes in vitro.

In this study the potential of clinically relevant alumina ceramic and metal wear particles to induce an in vitro inflammatory response was assessed in human monocytes and lymphocytes isolated from healthy donors by measuring prostaglandin E2 (PGE2) levels and mRNA expression of various pro-inflammatory cytokines. Bacterial lipopolysaccharide (LPS) was used as positive control. LPS significantly increased PGE2 levels in the incubation medium of monocyte cultures after 24 h. Alumina had no effect on PGE2 production, whereas metals induced a concentration-dependent increase in PGE2 release, that was statistically significant at the dose of 0.1 mg/ml. In lymphocytes, LPS elicited a weak but significant increase in PGE2 release, whereas both alumina and metals did not modify PGE2 amounts at any of the concentrations tested. The gene expression of a number of pro- and anti-inflammatory cytokines was assessed in monocytes and lymphocytes exposed to LPS, 0.1 mg/ml alumina or 0.1 mg/ml metals for 24 h. In monocytes, LPS caused a 2-fold increase in interleukin-1beta (IL-1beta) mRNA levels. The exposure of monocytes to metals resulted in a selective increase in IL-1beta mRNA accumulation (+48% compared to control). By contrast, alumina did not modify IL-1beta mRNA levels. None of the test substances elicited any response on purified lymphocyte population. These findings suggest that PGE2 production and IL-1 mRNA expression are a reliable marker to study the pro-inflammatory effects of wear debris in vitro. The lower activity of alumina compared to metals suggests that the former should be preferred in implants for its favorable biological and mechanical behavior.

Kaposi's sarcoma in transplant and HIV-infected patients: an epidemiologic study in Italy and France.

BACKGROUND: A follow-up study was conducted in Italy and in France to compare the epidemiology of Kaposi's sarcoma (KS) between human immunodeficiency virus (HIV)-infected people and transplant recipients. METHODS: In all, 8,074 HIV-positive individuals (6,072 from France and 2,002 HIV-seroconverters from Italy) and 2,705 Italian transplant recipients (1,844 kidney transplants, 702 heart transplants, and 159 liver transplants) were followed-up between 1970 and 2004. Standardized incidence ratios (SIRs) and 95% confidence intervals (CIs) were computed to estimate the risk of KS, as compared to sex- and age-matched Italian and French populations. Incidence rate ratios (IRRs) were used to identify risk factors for KS. RESULTS: A 451-fold higher SIR for KS was recorded in HIV-infected subjects and a 128-fold higher SIR was seen in transplant recipients. Significantly increased KS risks were observed in HIV-infected homosexual men (IRR=9.7 in France and IRR=6.7 in Italy vs. intravenous drug users), and in transplant recipients born in southern Italy (IRR=5.2 vs. those born in northern Italy). HIV-infected patients with high CD4+ cell counts and those treated with antiretroviral therapies had reduced KS risks. In relation to duration of immunosuppression, KS occurred earlier in transplant patients than in HIV-seroconverters. CONCLUSIONS: This comparison highlighted that the risk of KS was higher among HIV-infected individuals than in transplant recipients, and that different co-factors are likely to influence the risk of KS. Moreover, the early KS occurrence in transplant recipients could be associated with different patterns of progressive impairment of the immune function.

RGDS peptide inhibits activation of lymphocytes and adhesion of activated lymphocytes to human umbilical vein endothelial cells in vitro.

The Arg-Gly-Asp (RGD) motif is known to mediate cell adhesion to several extracellular matrix components as well as cell-cell interactions. In the present study, we investigated whether the RGDS peptide interferes with cell-cell recognition-based events such as allogeneic activation of PBMC and PBMC adhesion to human umbilical vein endothelial cells (HUVEC). We show here for the first time, to our knowledge, that RGDS significantly inhibits adhesion of activated PBMC to HUVEC; in addition, RGDS inhibits PBMC allogenenic activation in human mixed lymphocyte reaction assays. Caspases played a pivotal role in both events, because preventing their activation abolished or strongly reduced the observed inhibitory effect. The RGDS antirecognition effect was strongly increased by pretreatment of HUVEC with RGDS, which affected mostly T lymphocyte adhesion to HUVEC. These results indicate that PBMC allogeneic activation, as well as reciprocal recognition between activated PBMC and endothelial cells, are RGDS-dependent events that occur through a dual effect involving anti-adhesive and caspase-dependent mechanisms. These data suggest a potential role of RGDS in cell-mediated immunity, inflammation and organ transplantation.