Malignant peritoneal mesothelioma in a 16-year-old girl: presentation of a rare disease.

Malignant peritoneal mesothelioma is extremely rarely seen in young patients.A 16 year-old girl presented with appendicitis-like acute abdominal pain. Intra-operatively, multiple confluent peritoneal nodules were seen on the entire greater omentum and in the pelvis infiltrating the uterus and both ovaries. Biopsies were obtained and interpreted as serous ovarian carcinoma. Radical surgical resection and hyperthermic intraperitoneal chemotherapy -(HIPEC) with carboplatin was performed and followed by 2 cycles of carboplatin/paclitaxel. Histological reevaluation showed characteristic features of epithelioid peritoneal mesothelioma and ruled out serous ovarian cancer. Therapy was continued with 6 cycles of pemetrexed/cisplatin.3 months after end of chemotherapy vital tumor tissue was found in the recess behind the liver, which could be resected completely. The patient is currently disease-free 17 months after initial diagnosis.Malignant peritoneal mesothelioma in young female patients might be under-recognized and possibly misdiagnosed as ovarian serous carcinoma in some cases. International and interdisciplinary cooperation is necessary in order to provide evidence based guidelines for diagnosis and treatment in the future.

T cell stimulation via the erythrocyte receptor. Synergism between monoclonal antibodies and phorbol myristate acetate without changes of free cytoplasmic Ca++ levels.

We observed that certain E-receptor antibodies (CD2 antibodies) can induce proliferation of resting human T cells in the presence of PMA, while other CD2 antibodies fail to have such an effect. The same CD2 antibodies that were mitogenic in the presence of PMA (9.6, X11, VIT13), but not the nonreactive ones, were also able to induce T cell proliferation via the so-called alternative pathway of T cell activation, i.e., when added pairwise in certain combinations to T cells in the absence of PMA. While the simultaneous addition of two comitogenic CD2 antibodies (9.6 or X11 plus VIT13) or the addition of a single nonmitogenic CD3 antibody (VIT3) led to a clearcut elevation of intracellular Ca++ levels, no such effect could be observed after the addition of one CD2 antibody alone. Even in the presence of PMA, one comitogenic CD2 antibody alone was unable to trigger a significant Ca++ response, although this combination induced a proliferative response. These data indicate that, distinguishable by their influence on free cytoplasmic Ca++, there are two different mechanisms of T cell activation via CD2. While simultaneous triggering with two antibodies leads to cell proliferation preceded by an increase of Ca++ levels, stimulation with one antibody plus PMA results in proliferation without a measurable early Ca++ response. We conclude that T cells treated by certain CD2 antibodies alone already recognize an activation signal probably unrelated to Ca++ homeostasis, a signal that can further be developed by PMA to result in a completely developed proliferative response.

Interaction of CD31 with a heterophilic counterreceptor involved in downregulation of human T cell responses.

CD31 is a 130-kD glycoprotein of the immunoglobulin (Ig) superfamily expressed on the surface of endothelial cells, platelets, and several leukocyte subsets. Previous reports indicated that CD31 can mediate intercellular adhesion via both homophilic and heterophilic interaction mechanisms. Using a soluble recombinant CD31-Ig fusion protein (CD31 receptor globulin [Rg]), we demonstrate here that human CD31- T lymphocytes and CD4+CD31- T cell clones express a heterophilic CD31 ligand that is upregulated 18 h after activation. Interaction of CD31Rg with CD31- T helper cell (Th) clones was divalent cation independent but could be blocked by heparin, thus indicating that the CD31 counterreceptor on T cells can be distinguished from the ligands identified on other cell types. Moreover, a single chain protein of 120 kD was precipitated by CD31Rg from the lysates of CD31- Th clones. CD31Rg completely downregulated the proliferative response and cytokine production (interleukin-4, interferon-gamma, and tumor necrosis factor-alpha) of CD31- Th clones when the cells were maximally stimulated via immobilized CD3 monoclonal antibody. These results suggest that interaction of CD31 with a heterophilic counterreceptor on T lymphocytes can interfere with a positive regulatory pathway of T cell activation, or directly signal T cells to downregulate immune function.

Retrobulbar T cells from patients with Graves' ophthalmopathy are CD8+ and specifically recognize autologous fibroblasts.

Graves' ophthalmopathy is an autoimmune condition characterized by T cell infiltration of the retrobulbar tissue. Phenotypic and functional analysis of these infiltrating cells may provide insight into the pathogenesis of the disease. IL-2-responsive cells were therefore grown out of the retrobulbar tissue from two patients with severe Graves' ophthalmopathy undergoing orbital decompression surgery, and six T cell lines were established and characterized. They consisted predominantly of CD8 + CD45RO+ cells and secreted IL-4, IFN-gamma, and IL-10 upon activation. When screened for their antigen reactivity, all lines proliferated in response to stimulation with autologous retrobulbar fibroblasts in an HLA class I-restricted manner, but did not recognize autologous peripheral blood mononuclear cells, crude eye muscle extract, allogeneic cells, or purified protein derivate of Mycobacterium tuberculosis. In contrast, PBMC from the same patients responded readily to purified protein derivate of Mycobacterium tuberculosis and allogeneic PBMC, but did not recognize autologous fibroblasts. Interestingly, only one of the six retrobulbar T cell lines displayed cytotoxicity towards its specific target cell population. These results suggest that the retrobulbar fibroblasts are a major T cell target in Graves' ophthalmopathy. Pronounced cytokine production in the absence of target cell cytotoxicity may explain fibroblast proliferation, glycosaminoglycan secretion, and secondary eye muscle enlargement in this condition.

Phase I study of tumor Ag-loaded IL-12 secreting semi-mature DC for the treatment of pediatric cancer.

BACKGROUND: Cancer vaccines employing DC in their capacity as APC have been tolerated well and have shown some efficacy in clinical studies. IL-12, a cytokine critical for type 1 T-helper (Th1) lymphocyte and cytotoxic T-lymphocyte (CTL) differentiation, when released from a DC-based cancer vaccine, may support the generation of a cellular T-cell response. METHODS: We applied tumor cell lysate plus keyhole limpet hemocyanin (KLH)-loaded and 48-h lipopolysaccharide (LPS) plus IFN-gamma-stimulated fully mature DC, which do not release IL-12, subcutaneously to eight patients, and maximally 6-h stimulated semi-mature (sm) DC, which are potent producers of IL-12, subcutaneously (n=6) or intranodally (n=8) as a cancer vaccine to patients suffering from advanced solid pediatric malignancies. RESULTS: No serious adverse events were observed following application of IL-12-releasing smDC. Following immunization the majority of patients responded positively to KLH in a delayed-type hypersensitivity (DTH) test. In addition, three of six intranodally treated patients responded to the tumor Ag in the DTH test. DISCUSSION: We conclude that treatment with a DC-based cancer vaccine enabled to release the immune regulatory cytokine IL-12 is safe and feasible and has the potential to induce a cellular immune response in pediatric cancer patients.

[Tolerance of magnetic resonance imaging in children and adolescents performed in a 1.5 Tesla MR scanner with an open design]. / Untersuchungstoleranz von Kindern und Adoleszenten in einem 1,5 Tesla MR-Tomografen mit offenem Magnetdesign.

PURPOSE: To investigate the tolerance of MR examinations in children and adolescents performed in a 1.5 Tesla MR scanner with an expanded bore diameter. METHOD AND MATERIALS: 163 patients, ages 4 to 25, underwent MR examinations in a 1.5 Tesla MR scanner with an open design (MAGNETOM Espree, Siemens, Erlangen, Germany), characterized by a compact length of 125 cm and an expanded 70 cm bore diameter. MR imaging of the brain was carried out in most cases (78.5 %), followed by examinations of the spinal canal (9.8 %), the extremities (9.2 %) and the neck (2.5 %). The patients were divided into four age groups and the success rate, motion artifacts and diagnostic quality of the MR examinations were assessed using a 3-grade scale. RESULTS: In 119 of 163 patients (73.0 %), MR examination was possible without any motion artifacts. With respect to the different age groups, 41.7 % of the 4 - 7-year-old children, 67.6 % of the 8 - 10-year-old children, 84.1 % of the 11 - 16-year-old children and 95.8 % of the patients older than 17 showed tolerance grade I without motion artifacts and excellent diagnostic image quality. In 39 of 163 children (23.9 %), the MR images showed moderate motion artifacts but had sufficient diagnostic quality. With regard to the different age groups, 52.8 % of the 4 - 7-year-old children, 26.5 % of the 8 - 10-year-old children, 15.9 % of the 11 - 16-year-old children and none of the patients older than 17 showed tolerance grade II with moderate motion artifacts and sufficient diagnostic image quality. In only 4 of 124 children < 10 years old and 1 child > 10 years old, the MR examination was not feasible and had to be repeated under sedation. CONCLUSION: Pediatric MR imaging using a 1.5 Tesla MR scanner with an open design can be conducted in children and adolescents with excellent acceptance. The failure rate of 3.0 % of cases for pediatric MR imaging is comparable to that of a conventional low-field open MR scanner.

Donor leukocyte infusion after hematopoietic stem cell transplantation in patients with juvenile myelomonocytic leukemia.

Juvenile myelomonocytic leukemia (JMML) is a clonal myeloproliferative disorder of early childhood. In all, 21 patients with JMML who received donor leukocyte infusion (DLI) after allogeneic hematopoietic stem cell transplantation (HSCT) for either mixed chimerism (MC, n=7) or relapse (n=14) were studied. Six patients had been transplanted from an HLA-matched sibling and 15 from other donors. Six of the 21 patients (MC: 3/7 patients; relapse: 3/14 patients) responded to DLI. Response rate was significantly higher in patients receiving a higher total T-cell dose (> or =1 x 10(7)/kg) and in patients with an abnormal karyotype. None of the six patients receiving DLI from a matched sibling responded. Response was observed in five of six patients who did and in one of 15 children who did not develop acute graft-versus-host disease following DLI (P=0.01). The overall outcome was poor even for the responders. Only one of the responders is alive in remission, two relapsed, and three died of complications. In conclusion, this study shows that some cases of JMML may be sensitive to DLI, this providing evidence for a graft-versus-leukemia effect in JMML. Infusion of a high number of T cells, strategies to reduce toxicity, and cytoreduction prior to DLI may improve the results.

Management of chronic immune thrombocytopenia in children and adolescents: lessons from an Austrian national cross-sectional study of 81 patients.

Chronic immune thrombocytopenia (cITP) is often associated with an underlying predisposition towards autoimmunity, recognition of which is relevant to guide treatment. International recommendations on diagnostic steps and therapeutic measures of cITP in childhood exist. However, due to the low prevalence (1-2/100,000) and a variation of availability of immunological and hematological tests and treatments across pediatric units, we postulated that these guidelines are not uniformly adhered to and that immune dysregulation syndromes remained undiscovered. To delineate the current management of children and adolescents with cITP in Austria, we performed a nationwide cross-sectional study. Between 2011 and 2014, 81 children with cITP were seen at seven centers (median age 8.75 years; range 1-17; female:male ratio 47:34) at 641 visits during 180 patient years after diagnosis of cITP (>12 months ITP duration). Additional diagnoses were noted, most frequently immune or autoimmune disorders, hematologic diseases, or infections (in 37.3%, including Evans syndrome, autoimmune lymphoproliferative syndrome, systemic lupus erythematosus, and Fanconi anemia), or other symptoms like bi- or pancytopenia (n=9), lymphoproliferation or granulomatous inflammation (n = 3). Both decision to treat as well as choice of treatment varied: smaller centers tended to observe more frequently, larger centers applied a pattern of treatment modalities that appeared to depend less on bleeding tendency than on center policy. More than 50% of therapeutic interventions occurred in bleedings scores ≤2 (of 5), suggesting a strong psychosocial intention to treat. Platelet increment upon 479 therapeutic interventions of eight types was evaluated, with multiple treatment approaches being pursued sequentially in refractory patients. These data confirm the hypothesis of heterogeneous diagnostic and therapeutic management of cITP in Austrian children and corroborate the need for (1) a precise panel of parameters to exclude underlying disorders and (2) for biomarkers to predict treatment response.

Improved outcome of treatment-resistant high-risk Langerhans cell histiocytosis after allogeneic stem cell transplantation with reduced-intensity conditioning.

Children with multisystem Langerhans cell histiocytosis (LCH) and risk organ involvement who fail to respond to conventional chemotherapy have an extremely poor prognosis. Myeloablative stem cell transplantation (SCT) as a possible salvage approach for these patients has been associated with a high risk of transplant-related mortality. Therefore, allogeneic stem cell transplantation following a reduced-intensity conditioning regimen (RIC-SCT) has recently been performed as an alternative salvage approach. We report on the experience with allogeneic RIC-SCT in nine pediatric high-risk LCH patients. Conditioning regimen included fludarabine in all patients, melphalan in eight patients, total lymphoid irradiation in six patients, total body irradiation in two, antithymocyte globulin in five, and Campath in four patients. RIC-SCT was well tolerated with regard to common procedure-related complications. Two patients died 50 and 69 days after RIC-SCT, respectively. Seven out of the nine patients survived and showed no signs of disease activity (including one with nonengraftment and full autologous hematopoietic recovery) after median follow-up of 390 days post-SCT. Based on this observation, we conclude that RIC-SCT is a feasible procedure with low transplant-related morbidity and mortality and a promising new salvage approach for high-risk LCH patients with resistant risk organ involvement.

Transplantation of highly purified peripheral blood CD34+ cells from HLA-mismatched parental donors in 14 children: evaluation of early monitoring of engraftment.

HLA-mismatched family members may represent an important cell source for patients that require stem cell transplantation but lack both a matched sibling donor and a closely matched unrelated donor. We report the outcome of 19 transplantations from HLA two- or three- loci mismatched parental donors in which 14 pediatric patients with hematological malignancies or other disorders, received a median of 21.5 x 106 (range, 5.4-58) highly purified CD34+peripheral blood stem cells (PBSC), as well as 4.7 x 104 (range, 0.4-12) donor T cells per kg body weight. T cell depletion was performed using a two-step CD34-positive selection on two different magnetic beads devices. Ten of 14 patients presented with rapid myeloid engraftment. The four patients who presented with graft failure (two non-engraftments, two rejections) received a second stem cell graft and one a third. Graft rejection was detected early by polymerase chain reaction (PCR) analysis of FACS-sorted T cells. Eight of the 14 patients are still alive after a median observation period of 15. 6 months (range, 3-31.3) with full donor chimerism in all hematopoietic cell lineages. No acute organ graft-versus-host disease (GVHD) and no chronic GVHD have occurred. One patient experienced relapse of leukemia. We conclude that transplantation of allogeneic PBSC from haploidentical donors will open new perspectives for pediatric patients for whom an HLA-matched stem cell graft is not available. Close monitoring of recipient and donor hematopoiesis might be of clinical value, to recognize early engraftment or rejection.

A simple and rapid slide blot method to quantify cytokine-mRNA in small numbers of lymphocytes.

In this study we describe an in situ hybridization protocol suitable for the measurement of interleukin mRNAs in small numbers of cells in suspension. In this procedure defined numbers of such cells are coated onto defined areas of microscopic slides using LAB-TEK tissue culture chamber slides. 32P-labelled oligonucleotides are then hybridized to them in situ. Binding of the probes is measured by autoradiography using X ray film followed by densitometry (slide blot) or, as in standard in situ protocols, by exposure to photoemulsion. In experiments designed to demonstrate the specificity and feasability of this protocol, peripheral blood T cells were activated with mitogenic stimuli and oligonucleotide probes specific for IL-2, IFN-gamma, or a control probe (IL-2 random) were hybridized to them. Both lymphokine genes were found to be transcribed in two discrete phases with the first peak at 12 h and another peak 48 h after stimulation, as measured semi-quantitatively on a per cell basis using X ray film exposure. The proposed experimental protocol supports the advantages of X ray film autoradiography such as rapidity, simplicity and the objectivity of densitometric evaluation, but also permits microscopic evaluation of individual cells as performed in classical in situ hybridization protocols using photoemulsion.

Induction of human complement activation without cytolysis by mouse monoclonal antibodies to human leukocyte antigens.

Ten monoclonal antibodies to human leukocyte subsets that had previously been shown to lyse their respective target cells in the presence of rabbit serum as complement source were evaluated for their cytolytic capacity with human complement. Four of the ten were lytic with human complement. All were of IgM type. Antibodies were also evaluated for their capacity to induce C3 binding to target cells. With this method we could demonstrate that, indeed, 3 of the 6 noncytolytic antibodies had the capacity to initiate the human complement activation process and to induce C3 binding. Two of these 3 antibodies were of IgM class (VIT3 and VIM13), one of IgG3 (562). From the practical point of view the most interesting of these 3 antibodies is the nonmitogenic anti-CD3 pan-T cell antibody VIT3. Therefore, this antibody was analyzed in more detail. VIT3 antibody concentrations needed to induce detectable C3 binding to human T cells are very low (down to 1 ng VIT3/ml). Human serum as complement source can also be considerably (100X) diluted before C3 binding becomes undetectable. Activation of C3 is a prerequesite for VIT3-induced C3 binding, and bound C3 seems to lack the C3a fragment. Bound C3, in contrast to the quickly occuring antigenic modulation of the CD3 complex and the simultaneous disappearance of the antibody coat, remains expressed also after prolonged incubation at 37 degrees C. C3 fragments bound to T cells after activation with VIT3 are also recognized by cells bearing C3 receptors of types CR1 and CR2.

Functional maturation of dendritic cells by exposure to CD40L transgenic tumor cells, fibroblasts or keratinocytes.

Tumor antigen pulsed dendritic cells (DCs) can induce anti-tumor immunity. We studied strategies for the reliable generation of such a tumor vaccine by functional maturation of DCs via interaction of CD40 with its ligand (CD40L, CD154). Exposure of immature DCs to CD40L transgenic cells, soluble recombinant human CD40L molecules or lipopolysaccharide induced expression of the co-stimulatory molecules, CD80 and CD86, and supported an allogeneic mixed leukocyte reaction. In contrast, the release of IL-12, an important mediator of anti-tumor immunity, and antigen-specific expansion and IFNgamma secretion of lymphocytes, was strongly triggered only by DCs exposed to CD40L transgenic cells.

Allogeneic bone marrow transplantation-mediated transfer of specific immunity against Toxocara canis associated with excessive IgE.

A girl with myelodysplastic syndrome (RAEB-T) received HLA-identical bone marrow from her younger brother after myeloablative treatment with busulfan and cyclophosphamide. After bone marrow transplantation, fever, exanthema, pruritus, and a pulmonary infiltrate were treated symptomatically. Bacterial cultures remained negative. Leukocyte engraftment began on day 10, and all blood cell populations proved to be of donor origin on FISH analysis. Increasing IgE levels (21 000 U/ml) on day 14 after BMT, positive RAST, specific IgG-antibodies, and missing Toxocara (T.) canis antigens in the recipient indicated donor-derived seroconversion. Before BMT, the recipient had been negative for T. canis in routine parasitological screening, and the donor proved to be positive for T. canis antibody by ELISA. This report suggests that the transfer of IgE immunity in the absence of detectable antigens may be responsible for IgE-mediated symptoms consistent with toxocara infection and confirms the need for parasite screening in donor medical examinations.

CMV-viraemia during allogenic bone marrow transplantation in paediatric patients: association with survival and graft-versus-host disease.

Sixty-one consecutive paediatric patients undergoing allogenic bone marrow transplantation (BMT) were screened prospectively for cytomegalovirus (CMV)-viraemia by PCR. Sixteen patients (26%) presented with single or recurrent CMV-viraemia between day -7 and + 100. Although only four of them had evidence of CMV-disease, there was a significant difference in the incidence of acute Graft versus Host Disease (GVHD) grade III-IV (75% vs 15.5%), liver-involvement (68% vs 13%) and the incidence of chronic GVHD (83% vs 13.8%) between CMV-PCR-positive and CMV-PCR-negative patients. Transplant-related mortality (TRM) was 43.7% in the CMV-PCR-positive group versus 13% in patients which had no evidence for CMV-viraemia. In all but one cases mortality in CMV-PCR positive patients was GVHD-associated. Pre-emptive therapy with gancyclovir in case of CMV-viraemia seemed to have no impact on incidence and severity of GVHD.

[Phenotypical and functional characterization of leukocytes--the CD-system]. / Phänotypische und funktionelle Charakterisierung von Leukozyten--das CD-System.

In several workshops held over the past few years 89 different cluster molecules have been identified on the surface of human leukocytes by the use of monoclonal antibodies. In this review we describe the principal of the CD clustering system and present a short survey of its application in clinic and basic research along with a complete listing of the CD molecules.

[Lymphocyte stimulation in the primed lymphocyte typing test by as yet unknown HLA-linked antigens (WP-alleles)]. / Lymphozytenstimulation im PLT-Test durch bisher unbekannte HLA-gekoppelte Antigene (WP-Allele).

Lymphocytes from HLA-identical unrelated donors often show positive stimulation in the mixed lymphocyte culture, possibly caused by alleles of HLA-linked, but not yet defined gene loci. In order to investigate such determinants lymphocytes from HLA-DR identical individuals were primed and tested in the PLT system. Family and population data indicate that such antigens exist and can be detected in vitro.