Selective killing of B-cell hybridomas targeting proteinase 3, Wegener's autoantigen

Wegener's granulomatosis (WG) is a rare disease characterized by granulomatous lesions, small vessel vasculitis and the presence of anti-neutrophil cytoplasmic autoantibodies (C-ANCAs) in the sera of affected patients. Their main target antigen is proteinase 3 (PR3), a neutrophil and monocyte-derived neutral serine protease. Since the standard treatment of this severe autoimmune disease, with cyclophosphamide and corticosteroids, is associated with potential side-effects, the development of a more specific immunotherapeutic agent is warranted. The key role of ANCA in the pathogenesis of vasculitis and the effectiveness of anti-CD20 antibodies in patients with refractory WG points towards the importance of B cells in WG. We thus evaluated a new approach to selectively eliminate PR3-specific autoreactive B cells by targeting the B-cell receptor. For this purpose we used a bifunctional recombinant fusion protein consisting of the antigen PR3 and a toxin. The cytotoxic component of this novel fusion protein was the ribonuclease angiogenin, a human toxin with low immunogenicity. The toxin was stabilized by exchanging the catalytically relevant histidine in position 44 with glutamine to eliminate the autoproteolytic activity. PR3H44Q was fused either to the N terminus or to the C terminus of angiogenin. The recombinant proteins were expressed in 293T cells. Binding assays demonstrated the appropriate size and recognition by anti-PR3 antibodies. Using TUNEL technology, we demonstrated that these autoantigen toxins kill proteinase 3-specific B-cell hybridomas selectively by inducing apoptosis. The data indicate that autoantigen-toxins are promising tools in the treatment or co-treatment of autoimmune diseases in which the antigen is known.     

Chromosomal changes during development and progression of prostate adenocarcinomas

Chromosomal copy number changes were investigated in 16 prostate carcinomas, 12 prostatic intraepithelial neoplasias (PIN; 4 low-grade and 8 high-grade) adjacent to the invasive tumour areas, and 5 regional lymph node metastases. For this purpose, comparative genomic hybridization (CGH) was performed and a copy number karyotype for each histomorphological entity was created. CGH on microdissected cells from non-neoplastic glands was carried out on 3 different cases to demonstrate the reliability of the overall procedure. None of the non-neoplastic tissue samples revealed chromosome copy number changes. In PIN areas, chromosomal imbalances were detected on chromosomes 7, 8q, Xq (gains), and on 4q, 5q, 8p, 13q and 18q (losses). In the primary tumours, recurrent (at least 25% of cases) gains on chromosomes 12q and 15q, and losses on 2q, 4q, 5q, Xq, 13q and 18q became apparent. Losses on 8p and 6q as well as gains on 8q and of chromosome 7 were also detected at lower frequencies than previously reported. The pooled CGH data from the primary carcinomas revealed a novel region of chromosomal loss on 4q which is also frequently affected in other tumour entities like oesophageal adenocarcinomas and is supposed to harbour a new tumour suppressor gene. Gains on chromosome 9q and of chromosome 16 and loss on chromosome 13q were observed as common aberrations in metastases and primary tumours. These CGH results indicate an accumulation of chromosomal imbalances during the PIN-carcinoma-metastasis sequence and an early origin of tumour-specific aberrations in PIN areas.     

Dexa-BEAM is not effective in patients with relapsed or resistant aggressive high-grade non-Hodgkin's lymphoma

The aim of the present study was to evaluate the feasibility and response of the Dexa-BEAM regimen as a salvage therapy followed by high-dose chemotherapy (HDCT) with peripheral blood stem cell transplantation (PBCST) in responding patients with high-grade relapsed or resistant aggressive non-Hodgkin's lymphoma (NHL). Sixteen pretreated patients (mean age 44, range 26-59) with relapsed (8) or resistant (8) NHL were treated with 1-4 cycles of Dexa-BEAM (dexamethasone, BCNU, etoposide, cytarabine, melphalan) in order to attain maximal response. Patients achieving complete response (CR) or partial response (PR) received HDCT with PBSCT. The conditioning regimen used was BEAM. Three patients achieved CR and one patient PR, resulting in an overall response rate of 25%. Three of four responding patients underwent high-dose chemotherapy and were successfully transplanted with autologous blood stem cells. Progressive disease developed in one patient after transplantation. Myelosuppression (WHO grade III- grade IV), the major side effect, was observed in all courses of Dexa-BEAM. Myelosuppression-related infection WHO grade IV occurred in four patients. The protocol was not well tolerated in this heavily pretreated group of patients with four severe myelosuppression-related infections WHO grade IV and one treatment-related death. The overall response rate in this study is not comparable to other salvage regimens published and led to the discontinuation of the trial. In conclusion Dexa-BEAM was only effective in a minority of patients with refractory or relapsed aggressive NHL and was not useful as a cytoreductive regimen prior to HDCT.     

Role of hematotoxicity and sex in patients with Hodgkin's lymphoma: an analysis from the German Hodgkin Study Group.

PURPOSE: Several scores have described sex as a prognostic factor in patients with Hodgkin's lymphoma (HL). However, little is known how sex-specific factors influence treatment outcome. We systematically investigated sex differences with regard to pretreatment characteristics and therapy-related variables, and examined their influence on the outcome of HL patients. PATIENTS AND METHODS: This analysis comprises 4,626 HL patients of all prognostic risk groups who were enrolled onto the multicenter studies HD4 to HD9 of the German Hodgkin Study Group. At 5.5 years, 2,050 female and 2,576 male patients were analyzed. RESULTS: Male and female patients had similar prognostic factors. There was more acute chemotherapy-related hematotoxicity in women, especially more severe leucopenia (WHO grade 3/4, 69.9% female and 55.2% male; P < .0001). Importantly, this did not translate into more infections. Female patients had similar response rates but fewer relapses and deaths, leading to a significantly better freedom from treatment failure (FFTF; at 66 months, 81% female [95% CI, 79% to 82%] and 74% male [95% CI, 72% to 76%]). Severe leucopenia during chemotherapy was strongly associated with better FFTF, both for males and females. In addition, when only those patients who developed severe leucopenia within the first two cycles of chemotherapy were included, the factor maintained its protective role. CONCLUSION: The protective role of severe leucopenia suggests the testing of a more individualized therapy. In future trials, this therapy may be tailored in a response-adapted manner depending on the individual toxicity profile within the first cycles.     

TNF-α expression and apoptosis-regulating proteins in oral lichen planus: a comparative immunohistochemical evaluation

Apoptosis appears to be the mode of cell death by which damaged cells are removed from the lesional tissue in oral lichen planus (OLP). In the present study, OLP biopsies were immunohistochemically evaluated for TNF-alpha and apoptosis-regulating proteins in an attempt to compare their phenotypic expression. Deparaffinized tissue sections from 22 OLP and 10 control oral biopsy specimens were immunohistochemically stained with anti-Bcl-2, anti-Bcl-x, anti-Bax and anti-TNF-alpha antibodies. Keratinocytes did not show any immunoreactivity for Bcl-2, while a uniform intense staining for this protein was evident in the lymphocytic infiltrate of OLP specimens. Immunoreactivity for TNF-alpha was seen in 17/22 OLP cases. All control tissues were TNF-alpha negative, thus indicating a possible involvement of this cytokine in the pathogenesis of OLP The differences in the staining intensities of Bcl-x and Bax between OLP and normal epithelium were slight; therefore an obvious association of the phenotypic TNF-alpha expression with these apoptosis-regulating proteins was not apparent.     

A pancreatic pseudocyst with acute hemorrhage in a child--secondary to a spherical duodenal duplication? A case report.

Duodenal duplications are rare congenital malformations with variable and non-specific symptoms. A spherical duodenal duplication associated with a pancreatic pseudocyst causing an acute bleeding due to a vascular erosion in a 16-month old child is presented. The possibility of a causal relationship between duodenal duplication and pancreatic pseudocyst is discussed.