A Single-center Experience on the Value of Pancreas Graft Biopsies and HLA Antibody Monitoring After Simultaneous Pancreas-Kidney Transplantation.

BACKGROUND: In simultaneous pancreas-kidney transplantation (SPKT), monitoring of the pancreas allograft is more complex than the kidney allograft due to difficulties in obtaining pancreas histology and weak clinical evidence supporting the role of donor-specific antibodies (DSA). METHODS: We performed a single-center retrospective analysis of all 17 SPKT recipients who underwent a total of 22 pancreas allograft indication biopsies from October 2009 to September 2012. Fifteen patients had at least 2 DSA measurements: pretransplantation and at the time of biopsy. RESULTS: All 7 patients (100%) with post-transplantation DSA-positivity (de novo: n = 6; persistent: n = 1) at biopsy had at least 1 rejection episode either of the pancreas (n = 4) or the kidney (n = 3), with 3 antibody-mediated rejections (AMR). In contrast, only 4 of 8 patients (50%) without post-transplantation DSA had evidence of rejection, with 1 AMR. Findings during pancreas allograft biopsy procedures led to a change of immunosuppressive therapy in 11 of 15 (73%) patients. Patient survival, graft survival, and function were not adversely affected by the presence of post-transplantation DSA. One major and 2 minor procedure-related complications occurred during the pancreas biopsies. CONCLUSIONS: In this small retrospective analysis, pancreas allograft histology provided the most therapeutically relevant information, rather than the kidney histology or DSA monitoring.

Immunoglobulin induction therapy in renal transplant recipients: Effects on immunoglobulin and regulatory antibody levels.

We have previously shown that high pretransplant regulatory autoantibodies are associated with better kidney graft outcome. To analyze the effect of intravenous immunoglobulin (IVIG) induction therapy on these regulatory antibodies, we performed a prospective randomized study in 50 renal transplant recipients who were randomly assigned to receive 7 x 10 g IVIG or 7 x 10 g IV albumin infusions. Basic immunosuppressive therapy consisted of tacrolimus/azathioprine (n = 24) and tacrolimus/mycophenolate mofetil (n = 26), respectively. ELISA was used to assess IgG-/IgA-anti-Fab, -anti-F(ab)2 and -anti-hinge regulatory antibodies. IVIG induction therapy resulted in upregulation of serum IgG and IgA levels within the first 20 days posttransplant (P = .001, IgG; P = .04, IgA), so that a significant IgG deficiency was found only in non-IVIG patients (day 10: IgG <6 g/L: 7/25 (28%) non-IVIG versus 0/25 IVIG patients; P = .005). As the IVIG charges contained all of the regulatory antibodies tested, intravenous administration of these antibodies explain the elevated IgG- and IgA-anti-F(ab)2 antibody levels found in IVIG compared to non-IVIG patients on day 10 (P = .005 and P = .04, respectively). Our data indicated that IVIG induction prevented severe IgG deficiency in the early posttransplant period but had no impact on severe infectious complications. IVIG induction enhanced immunoregulatory antibody levels early posttransplant, which might provide graft protective effects.

Associations of blood levels of PCB, HCHS, and HCB with numbers of lymphocyte subpopulations, in vitro lymphocyte response, plasma cytokine levels, and immunoglobulin autoantibodies.

Pentachlorophenol (PCP), hexachlorocyclohexane-[alpha], -beta, and -[gamma] (HCH-[alpha], -beta, and -[gamma]), polychlorinated biphenyls (PCBs), and hexachlorobenzene (HCB) are widely distributed industrial chemicals. They are suspected to induce immunologic impairments in exposed individuals. We examined dose-response relationships of blood levels of these chemicals with cellular (numbers of lymphocyte subpopulations, in vitro lymphocyte response) or humoral (plasma cytokine levels, immunoglobulin autoantibodies) immunologic dysfunctions. We studied 146 patients who had been occupationally exposed primarily to PCBs for more than 6 months. Lymphocyte subpopulations, in vitro responses to mitogens and allogeneic stimulator cells, plasma neopterin, cytokines, soluble cytokine receptors, soluble adhesion molecules, anti-Ig autoantibodies, and liver transaminases were determined. Blood levels of the different compounds were strongly correlated with one another. There were only weak dose-response relationships between blood levels of PCBs with cellular immune parameters, and of HCHs and HCB with humoral immune parameters. An exception was the statistically significant negative association of HCB with interferon-[gamma] (IFN-[gamma]), indicating that HCB has a significant impact on Th1 lymphocytes. Patients with HCB blood levels above the mean of 1,109 ng/L more often had undetectable IFN-[gamma] blood levels than patients below the mean. Patients with increased PCB 138 (> 710 ng/L) had more frequently undetectable interleukin-4 blood levels than patients with PCB 138 below the mean, and patients with increased PCB 101 (> 31 ng/L) more often had low DR+ cell counts in the blood (< 190/microL) than patients with PCB 101 below the mean. To assess possible cumulative effects, we compared patients who had blood levels of all compounds below background with patients who had blood levels of all compounds above background. Patients with low or absent blood levels of the compounds studied had higher IFN-[gamma] plasma levels, providing some evidence for a cumulative effect of several weakly active compounds. In conclusion, exposure to PCBs, HCB, or HCHs is associated with weak immunologic abnormalities. These results contrast with those obtained in earlier studies of blood levels of PCP, which showed a strong dose-dependent relationship with immunologic impairments. Our data suggest that long-term exposure of patients to HCB suppresses IFN-[gamma] production.

Association of elevated blood levels of pentachlorophenol (PCP) with cellular and humoral immunodeficiencies.

It has long been suspected that pentachlorophenol (PCP) exerts a damaging influence on the immune system. In this study, the possible relationship between blood levels of PCP and immune function was studied in 190 patients who had been exposed for more than 6 mo to PCP-containing pesticides. The patients suffered from frequent respiratory infections and general fatigue. Lymphocyte subpopulations, in-vitro responses to mitogens, allogeneic stimulator cells, plasma neopterin, cytokines, soluble cytokine receptors, soluble adhesion molecules, and immunoglobulin autoantibodies were determined. A dose-response relationship between blood levels of PCP and cellular and humoral immune parameters was established. Blood levels of PCP were associated negatively with (a) total lymphocyte counts (p = .0002), CD4/CD8 ratios (p = .0015), and absolute counts of CD3+ (p < .0001), CD4+ (p < .0001), CD16+ (p < .0001), CD25+ (p = .0003), DR+ (p < .0001), CD8+/56+ (p = .020), and CD19+ cells (p = .092); (b) plasma levels of interleukin-2 (IL-2) (p < .0001), soluble IL-2R (p < .0001), IL-6 (p < .0001), IL-10 (p = .0039), interferon-gamma (IFN-gamma) (p < .0001), tumor necrosis factor-alpha (TNF-alpha) (p < .0001), transforming-growth factor-beta2 (p = .023), soluble IL-1 receptor antagonist (sIL-1 RA) (p < .0001), soluble intercellular adhesion molecule-1 (p = .0003); and (c) immunoglobulin (Ig) M-anti-Fab type autoantibodies (p = .0353). PCP levels were associated positively with (a) number of impaired stimulation assays per patient (p = .041); (b) number of circulating CD11b+ monocytes (p = .0015); and (c) plasma levels of neopterin (p < .0001), IL-4 (p = .020), and sIL-6R (p = .020). Compared with patients who had PCP plasma levels that were less than or equal to 10 microg/l, patients with blood levels of PCP that exceeded 10 microg/l experienced the following more often: low numbers of total blood lymphocytes (p = .054), CD3+ (p = .0014), CD4+ (p = .0001), DR+ (p = .0003), CD16+ (p = .0033), and CD25+ cells (p = .0033). In addition, the same aforementioned patients experienced the following more frequently: undetectable plasma levels of IL-2 (p = .0057), IL-6 (p = .042), IL-8 (p = .038), IL-10 (p = .0001), TNF-alpha (p = .0062), and IFN-gamma (p = .016); and impaired in-vitro responses of lymphocytes (p = .071). The authors concluded that increased blood levels of PCP were associated significantly with cellular and humoral immunodeficiencies. Recurrent respiratory infections and general fatigue could originate from PCP-associated immunosuppression.