Clinical trial results of the HER-2/neu (E75) vaccine to prevent breast cancer recurrence in high-risk patients: from US Military Cancer Institute Clinical Trials Group Study I-01 and I-02.

BACKGROUND: The authors conducted exploratory phase 1-2 clinical trials vaccinating breast cancer patients with E75, a human leukocyte antigen (HLA) A2/A3-restricted HER-2/neu (HER2) peptide, and granulocyte-macrophage colony-stimulating factor. The vaccine is given as adjuvant therapy to prevent disease recurrence. They previously reported that the vaccine is safe and effective in stimulating expansion of E75-specific cytotoxic T cells. Here, they report 24-month landmark analyses of disease-free survival (DFS). METHODS: These dose escalation/schedule optimization trials enrolled lymph node-positive and high-risk lymph node-negative patients with HER2 (immunohistochemistry [IHC] 1-3(+) ) expressing tumors. HLA-A2/A3(+) patients were vaccinated; others were followed prospectively as controls for recurrence. DFS was analyzed by Kaplan-Meier curves; groups were compared using log-rank tests. RESULTS: Of 195 enrolled patients, 182 were evaluable: 106 (58.2%) in the vaccinated group and 76 (41.8%) in the control group. The 24-month landmark analysis DFS was 94.3% in the vaccinated group and 86.8% in the control group (P = .08). Importantly, because of trial design, 65% of patients received a lower than optimal vaccine dose. In subset analyses, patients who benefited most from vaccination (vaccinated group vs control group) had lymph node-positive (DFS, 90.2% vs 79.1%; P = .13), HER2 IHC 1+-2+ (DFS, 94.0% vs 79.4%; P = .04), or grade 1 or 2 (DFS, 98.4% vs 86.0%; P = .01) tumors and were optimally dosed (DFS, 97.3% vs 86.8%; P = .08). A booster program has been initiated; no patients receiving booster inoculations have recurred. CONCLUSIONS: The E75 vaccine has clinical efficacy that is more prominent in certain patients. A phase 3 trial enrolling lymph node-positive patients with HER2 low-expressing tumors is warranted.

Post-transplantation lymphoproliferative disease: Epstein-Barr virus DNA levels, HLA-A3, and survival.

RATIONALE: Elevation in Epstein-Barr virus (EBV) circulating DNA has been proposed as a marker for development of post-transplant lymphoproliferative disease (PTLD), but few published data exist in the study of lung-transplant recipients. OBJECTIVES: To determine if elevated EBV DNA levels, in combination with other risk factors, were predictive of PTLD. METHODS: We conducted a retrospective, single-center study examining all lung transplant recipients (n = 296) and EBV DNA levels (n = 612) using real-time TaqMan polymerase chain reaction. There were 13 cases of PTLD overall, of which 5 occurred in the era of EBV DNA monitoring. MEASUREMENTS AND MAIN RESULTS: EBV DNA levels were distributed differently among seropositive and seronegative patients, with the latter having higher values (P < 0.0001). Among the cohort of pretransplantation seropositive patients, there was one diagnosed with PTLD. The EBV DNA level in this patient was elevated at the time of PTLD diagnosis (sensitivity = 100%, specificity = 100% for PTLD). Among the cohort of pretransplantation seronegative patients, there were four with a diagnosis of PTLD. In all four patients, the EBV DNA level was detectable (sensitivity = 100%, specificity = 24%), but in only two was it elevated (sensitivity = 50%, specificity = 22%). HLA-A3 expression in the recipient and/or donor conferred additional risk for PTLD among the seronegative patients (P = 0.026 to 0.003). No other PTLD risk factor was found. CONCLUSIONS: EBV DNA levels are a useful but imperfect predictor of PTLD in patients with lung transplants. Pretransplant EBV status affected the results of the assay and should be considered when interpreting test results. HLA-A3 was strongly linked to PTLD and may be a novel marker of PTLD risk.

Combined clinical trial results of a HER2/neu (E75) vaccine for the prevention of recurrence in high-risk breast cancer patients: U.S. Military Cancer Institute Clinical Trials Group Study I-01 and I-02.

PURPOSE: E75 is an immunogenic peptide from the HER2/neu protein, which is overexpressed in many breast cancer patients. We have conducted two overlapping E75 vaccine trials to prevent recurrence in node-positive (NP) and node-negative (NN) breast cancer patients. EXPERIMENTAL DESIGN: E75 (HER2/neu 369-377) + granulocyte macrophage colony-stimulating factor was given intradermally to previously treated, disease-free NP breast cancer patients in a dose escalation safety trial and to NN breast cancer patients in a dose optimization study. Local and systemic toxicity was monitored. Immunologic responses were assessed using in vitro assays and in vivo delayed-type hypersensitivity responses. Clinical recurrences were documented. RESULTS: One hundred and eighty-six patients were enrolled in the two studies (NP, 95; NN, 91). Human leucocyte antigen A2 (HLA-A2) and HLA-A3 patients were vaccinated (n = 101), whereas all others (n = 85) were followed prospectively as controls. Toxicities were minimal, and a dose-dependent immunologic response to the vaccine was shown. Planned primary analysis revealed a recurrence rate of 5.6% in vaccinated patients compared with 14.2% in the controls (P = 0.04) at a median of 20 months follow-up. As vaccine-specific immunity waned over time, the difference in recurrence lost significance at 26 months median follow-up (8.3% versus 14.8%); however, a significant difference in the pattern of recurrence persisted. CONCLUSIONS: E75 is safe and effective in raising a dose-dependent HER2/neu immunity in HLA-A2 and HLA-A3 NP and NN breast cancer patients. More importantly, E75 may reduce recurrences in disease-free, conventionally treated, high-risk breast cancer patients. These findings warrant a prospective, randomized phase III trial of the E75 vaccine with periodic booster to prevent breast cancer recurrences.

Beta-2 microglobulin-free HLA class I heavy chain (FHC) A3 and/or A30 soluble products contribute only minimally to serum FHC expression.

No monoclonal antibodies (mAbs) are presently available to measure the total amount of beta2-microglobulin-free HLA class I heavy chain (FHC) in sera. The available ELISA-based double determinant immunoassay (DDIA), established to measure FHC, uses two mAbs (TP25.99 and HC-10) that recognize a monomorphic determinant expressed on all HLA-B/C FHC products and a determinant expressed only on some HLA-A FHC products. This restricted reactivity implies that, in addition to HLA-B/C, HLA-A FHC products are also detected in individuals bearing HLA A3 and/or A30 allotypes. The aim of this study was to establish whether such restriction results in the detection of low FHC levels in individuals lacking HLA A3 and/or A30 allospecificities. The FHC mean concentration (+/- SD) in 294 healthy blood/bone marrow donors (HBDs) was 0.24 (+/- 0.2) mg/l. The grouping of HBDs according to their HLA-A FHC product reactivity with one, both or no mAbs did not result in any statistically significant differences (Mann-Whitney test: P > 0.05) between their median FHC concentrations. Since the absence of differences in their FHC levels was not attributable to a difference in the percentage distribution of HLA allotypes associated with high or low HLA-B/C FHC expression, our results indicate that FHC HLA A3 and/or A30 products detected in DDIA by these two mAbs only minimally contribute to FHC serum expression and that the assay is not limited by the failure to detect HLA-A FHC products in A3- and/or A30- individuals.

Donor-derived soluble HLA plasma levels can not be used to monitor graft rejection in heart transplant recipients.

OBJECTIVE: Increased levels of both donor- and recipient-derived HLA class I molecules (sHLA-I) can be found in serum or plasma of transplanted patients during rejection. Earlier data indicate that levels of donor-derived sHLA-I (dsHLA-I) correlate better with graft rejection than total sHLA Class I (Zavazava N, Kraatz E, Gassel AM, Muller-Ruchholtz W. Plasma MHC class I expression in cardiac graft patients: donor-specific soluble antigen in a pre-sensitized graft patient. Transplant Proc 1991;23:2258-2260; Claas FHJ, Jankowska-Gan E, DeVito LD, et al. Monitoring of heart transplant rejection using a donor-specific soluble HLA class I ELISA. Hum Immunol 1993;37:121). Therefore, quantifying donor-derived soluble counterparts of HLA Class I (sHLA-I) in the plasma of the recipient may offer a new possibility for non-invasive monitoring of rejection after organ transplantation. METHODS: In an extended study with 34 heart transplant recipients, we used sHLA-I specific ELISAs to monitor donor-derived soluble sHLA-A2, -A3, -A9, -B7, -B12 and B51. RESULTS: The assays were sensitive enough to detect dsHLA Class I in plasma of the recipients. However, the levels of sHLA were not found to be a useful tool for monitoring rejection. Rejection was often associated with low levels of donor sHLA. The recent finding that antibodies can inhibit the detection of sHLA molecules might explain this discrepancy. In order to test this hypothesis, patient sera were screened for the presence of anti-HLA antibodies and the results were related to the donor-derived sHLA levels. Only in four out of 34 patients HLA Class I specific antibodies could explain the low sHLA levels during rejection. CONCLUSIONS: In heart transplantation increased donor-derived sHLA levels are not a suitable marker for rejection and that antibody formation can not explain these results. Therefore, monitoring rejection episodes on the basis of donor-derived soluble HLA molecules is not a realistic approach to decrease the number of biopsies after heart transplantation.

Liver transplant recipient sera derived soluble HLA mediates allele specific CTL apoptosis.

BACKGROUND: Significant levels of donor soluble human leukocyte antigen (HLA) class I (sHLA) are present in patients after transplants. We investigated the possibility that sHLA may inhibit cytolytic T lymphocyte (CTL) activity by inducing apoptosis of the CTL, thereby serving as a mechanism for specific tolerance. METHODS: sHLA-A2 and A3 were isolated from the sera of liver transplant recipients by affinity chromatography. T cell bulk lines directed against HLA-A2 and HLA-A3 were generated by stimulation with HLA-A2, A3+ peripheral blood leukocytes and B-lymphoblastoid cells. Induction of T cell apoptosis by sHLA was analyzed by adding sHLA to allospecific CTL 4 or for 24 hr before flow cytometric analysis of propidium iodide and fluorescein isothiocyanate-conjugated annexin V stained cells. T cell receptor (TCR) engagement by sHLA was demonstrated using a monoclonal antibody specific for the TCR. RESULTS: sHLA-A3 inhibited CTL activity of a HLA-A3 T cell line by 53%, whereas sHLA-A2 had no effect. sHLA-A3 also increased T cell death by 77% over the control, whereas sHLA-A2 had no significant effect. However, sHLA-A2 induced 21% apoptosis of an anti-HLA-A2 T cell line, whereas sHLA-A3 caused only 3% apoptosis. The antibody complexed form of sHLA was ineffective in the induction of apoptosis. Preincubation of the T cells with anti-T cell receptor monoclonal antibody protected the T cells from sHLA-induced apoptosis, indicating that sHLA-TCR engagement is necessary for this process to occur. CONCLUSION: TCR-mediated apoptosis of alloreactive CTL may serve as a mechanism by which sHLA can modulate the immune response.

Serologic allogeneic chimerism.

BACKGROUND: At least some transplanted livers secrete soluble human leukocyte antigens (sHLA) of donor phenotype into the body fluids of recipients. The individuals in whom this phenomenon occurs are by definition serologic allogeneic chimeras. Because an allogeneic transplanted liver may induce tolerance to itself and other organs in animals of the donor strain, and because maintenance of a soluble antigen in the circulation of any animal in sufficient quantity for a sufficient period generally leads to tolerance, this phenomenon may be biologically important. This study was performed to determine how common this phenomenon is and whether it occurs after transplantation of organs other than the liver. METHODS: We studied 445 serum samples obtained from transplant recipients (liver, n=12; kidney, n=18; and heart, n=8) before and at various intervals after transplantation. All patients studied had allografts that had functioned for more than 1 year. We used an enzyme-linked immunosorbent assay to quantitate sHLA-A2 and sHLA-A1/A3/A11 (as a cross-reacting group). Donor and recipient combinations were selected in which measurable allotypes in donors were not present in recipients. In some instances, an additional allotype was present in a recipient but not in a donor. RESULTS: All liver transplant recipients had detectable donor sHLA in their serum samples after transplantation. In 72% of kidney and 50% of heart transplant recipients, donor sHLA was found persistently in serum samples obtained after transplantation. Interestingly, all heart transplant recipients of HLA-A3, but none of HLA-A2, had detectable donor sHLA in their serum samples, a finding that may be due to technical reasons. High and stable serum concentrations of donor sHLA characterize long-term stable allograft function. CONCLUSIONS: Donor sHLA is produced by all transplanted livers, most transplanted kidneys, and at least half of (but probably more) transplanted hearts. The hypothesis that donor sHLA may be tolerogenic to liver transplants can be expanded to include kidney and heart transplants.

[Relationship of histocompatibility groups to chronic HBV infections]. / Kronik HBV enfeksiyonu ile doku gruplari arasindaki iliski.

HLA-A, B, C and DR locus specificities studied in 168 patients (71 Chronic active Hepatitis, 97 Chronic Persistent Hepatitis) serologically and histopathologically proven Chronic Hepatitis B Virus infection. There were 113 men and 55 women with a mean age of 23.2 (21-52) years. Hundred and seventy four healthy subjects (107 men, 67 women) included in control group with a mean age of 26.4 (20-54) years. The frequency of HLA A3 (p < 0.01), HLA A11 (p < 0.01), HLA B35 (p < 0.05) and HLA B51 (p < 0.01) were significantly higher in patients than in healthy control subjects. Comparisons among the other HLA-A, B, C and DR locus were found to be statistically non-significant.

Serum ferritin, blood donation, iron stores and haemochromatosis.

Serum iron and ferritin concentrations were measured in 1,532 regular blood donors from South Wales who were undergoing HLA typing prior to registration on the British Bone Marrow and Platelet Donor Panel. Serum transferrin concentrations were determined for donors with serum iron concentrations > 24 mumol/l. There were 25 donors with transferrin saturations > 50% and 11 with transferrin saturations > 60%. There were five donors with serum ferritin concentrations > 200 micrograms/l (women) or > 300 micrograms/l (men). Two of the male donors had transferrin saturations > 50% and serum ferritin > 300 micrograms/l on repeat blood samples and are being treated by venesection. Donors with HLA-A3 did not differ from those without A3 in serum iron or ferritin concentrations. Even in the group of donors who were apparently homozygous for A3 there were neither abnormal serum iron nor ferritin concentrations. Although it is well established that measurements of transferrin saturation are required to detect homozygous haemochromatosis (HFE) in its earlier stages, the number of 'false-positive' results is likely to be unacceptably high for screening blood donors. Serum ferritin assays should identify donors with HFE and iron overload before the onset of liver damage. With two million regular donors and 300,000 new donors each year, a significant proportion of the U.K. population will be screened within 10 years. The assay of serum ferritin identifies donors with low levels of storage iron who are at risk of developing iron-deficiency anaemia. Furthermore, donation frequency may be increased for those donors with higher ferritin concentrations when blood supplies are low.