Quality of life in childhood immune thrombocytopenia: international validation of the kids' ITP tools.

BACKGROUND: The Kids ITP Tools (KIT) is a disease-specific measure of health-related quality of life for children with immune thrombocytopenia (ITP). To facilitate use in international trials it has been cross-culturally adapted for France, Germany, the United Kingdom and Uruguay. This study assessed the validity and reliability of the translated KIT in comparison to generic quality of life measures. METHODS: Children 2-18 years of age with ITP and their parents were recruited in France, Germany, the United Kingdom and Uruguay. Participants completed the KIT, PedsQL and KINDL. We examined the Pearson's correlation between these measures for our pooled sample and estimated the reliability over a 2-week time period. Findings were further explored by country. RESULTS: A total of 127 families (81 children self-reported) participated. Mean child-reported scores were: KIT 74.3 (SD = 15.3), PedsQL 81.3 (SD = 13.0), and KINDL 70.5 (SD = 14.3). Corresponding mean parent proxy-reported scores were: 70.6 (SD = 18.1), 75.7 (SD = 16.8) and 72.3 (SD = 12.7), respectively. Correlation between KIT and the generic measures was consistent with our a priori hypothesis (PedsQL r = 0.54, KINDL r = 0.48, both P < 0.0001). Child KIT scores for newly diagnosed ITP patients were significantly lower than for chronic ITP patients (67.3 vs. 77.3; P = 0.005). There was a significant correlation (P < 0.001) between the child and parent proxy KIT scores (ICC = 0.52). Child KIT test-retest reliability was acceptable at 0.71. CONCLUSIONS: The cross-culturally translated KIT is valid and reliable with acceptable correlation to the PedsQL and KINDL. There is a significant difference in child self-reported KIT scores between newly diagnosed and chronic ITP.

Two patterns of thrombopoietin signaling suggest no coupling between platelet production and thrombopoietin reactivity in thrombocytopenia-absent radii syndrome.

BACKGROUND: Thrombocytopenia with absent radii syndrome is defined by bilateral radius aplasia and thrombocytopenia. Due to impaired thrombopoietin signaling there are only few bone marrow megakaryocytes and these are immature; the resulting platelet production defect improves somewhat over time. A microdeletion on chromosome 1q21 is present in all patients but is not sufficient to form thrombocytopenia with absent radii syndrome. We aimed to refine the signaling defect in this syndrome. DESIGN AND METHODS: We report an extended study of 23 pediatric and adult patients suffering from thrombocytopenia with absent radii syndrome in order to scrutinize thrombopoietin signal transduction by immunoblotting and gel electrophoretic shift assays. In addition, platelet immunotyping and reactivity were analyzed by flow cytometry. Results were correlated with clinical data including age and platelet counts. RESULTS: Two distinct signaling patterns were identified. Juvenile patients showed abrogated thrombopoietin signaling (pattern #1), which is restored in adults (pattern #2). Phosphorylated Jak2 was indicative of activation of STAT1, 3 and 5, Tyk2, ERK, and Akt, showing its pivotal role in distinct thrombopoietin-dependent pathways. Jak2 cDNA was not mutated and the thrombopoietin receptor was present on platelets. All platelets of patients expressed normal levels of CD41/61, CD49b, and CD49f receptors, while CD42a/b and CD29 were slightly reduced and the fibronectin receptor CD49e markedly reduced. Lysosomal granule release in response to thrombin receptor activating peptide was diminished. CONCLUSIONS: We show a combined defect of platelet production and function in thrombocytopenia with absent radii syndrome. The rise in platelets that most patients have during the first years of life preceded the restored thrombopoietin signaling detected at a much later age, implying that these events are uncoupled and that an unknown factor mediates the improvement of platelet production.

Immature platelet count: a simple parameter for distinguishing thrombocytopenia in pediatric acute lymphocytic leukemia from immune thrombocytopenia.

BACKGROUND: Platelet counts below normal values define thrombocytopenia. However, platelet counts alone do not reveal the underlying pathomechanism. New blood cell counters provide additional information on platelet size and volume, and enable the distinction of sub-populations. In this preliminary study, we evaluate whether one of these markers can be used for diagnosis of isolated thrombocytopenia in children. PROCEDURE: We provide normal values for mean platelet volume (MPV), platelet distribution width (PDW), plateletcrit (PCT), platelet large cell ratio (P-LCR), platelet mean-frequent volume (P-MFV), relative immature platelet fraction (IPF%), and absolute IPF (IPF#) for 100 healthy children and analyzed 87 children with thrombocytopenia. RESULTS: In children with platelet production defects, IPF% was low, while in acute immune thrombocytopenia (ITP), IPF% was markedly increased (median 25.2%, P < 0.01), representing accelerated platelet turnover. Interestingly, children diagnosed with acute lymphocytic leukemia (ALL) also had elevated IPF% (median 10%, P < 0.01), suggesting that thrombopoiesis is stimulated despite virtual absence of bone marrow progenitors. Low IPF# was only found in patients with acute ITP. CONCLUSIONS: IPF% is a marker for thrombocytopenia due to defective platelet production while IPF#, representing the immature platelet count, might become a practical parameter to distinguish acute ITP from thrombocytopenia in children with newly diagnosed ALL (P < 0.01).

Continuous veno-venous single-pass albumin hemodiafiltration in children with acute liver failure.

OBJECTIVE: To investigate the applicability, efficacy, and safety of single-pass albumin dialysis in children. DESIGN: Retrospective data review of uncontrolled clinical data. SETTING: University-based pediatric intensive care unit collaborating with a local center for liver transplantation. PATIENTS: Nine children, aged 2 to 15 yrs, who were treated with single-pass albumin dialysis for acute liver failure of various origins under a compassionate-use protocol between 2000 and 2006. All patients met high-urgency liver transplantation criteria. INTERVENTIONS: Single-pass albumin dialysis was performed as rescue therapy for children with acute liver failure. MEASUREMENTS AND MAIN RESULTS: The decrease in hepatic encephalopathy (grades 1-4) and the serum levels of bilirubin, bile acids, and ammonium were measured to assess the efficacy of detoxification. As a measure of liver synthesis function, thromboplastin time and fibrinogen were analyzed. The safety of the procedure was assessed by documenting adverse effects on mean arterial blood pressure, platelet count, and clinical course. Seven out of nine patients were bridged successfully to either native organ recovery (n = 1) or liver transplantation (n = 6), one of them twice. Six out of nine patients undergoing single-pass albumin dialysis (ten treatments) survived. In six patients, hepatic encephalopathy could be reduced at least by one degree. Ammonium, bilirubin, and bile acid levels decreased in all patients. One patient had an allergic reaction to albumin. CONCLUSIONS: In childhood acute liver failure, treatment with single-pass albumin dialysis was generally well tolerated and seems to be effective in detoxification and in improving blood pressure, thus stabilizing the critical condition of children before liver transplantation and facilitating bridging to liver transplantation. It may be beneficial in avoiding severe neurologic sequelae after acute liver failure and thereby improve survival. Single-pass albumin dialysis is an inexpensive albumin-based detoxification system that is easy to set up and requires little training. Whether and to what extent single-pass albumin dialysis can support children with acute liver failure until native liver recovery remains unclear.

Survivin minigene DNA vaccination is effective against neuroblastoma.

The inhibitor of apoptosis protein survivin is highly expressed in neuroblastoma (NB) and survivin-specific T cells were identified in Stage 4 patients. Therefore, we generated a novel survivin minigene DNA vaccine (pUS-high) encoding exclusively for survivin-derived peptides with superior MHC class I (H2-K(k)) binding affinities and tested its efficacy to suppress tumor growth and metastases in a syngeneic NB mouse model. Vaccination was performed by oral gavage of attenuated Salmonella typhimurium SL7207 carrying pUS-high. Mice receiving the pUS-high in the prophylactic setting presented a 48-52% reduction in s.c. tumor volume, weight and liver metastasis level in contrast to empty vector controls. This response was as effective as a survivin full-length vaccine and was associated with an increased target cell lysis, increased presence of CD8(+) T-cells at the primary tumor site and enhanced production of proinflammatory cytokines by systemic CD8(+) T cells. Furthermore, depletion of CD8(+) but not CD4(+) T-cells completely abrogated the pUS-high mediated primary tumor growth suppression, demonstrating a CD8(+) T-cell mediated effect. Therapeutic vaccination with pUS-high led to complete NB eradication in over 50% of immunized mice and surviving mice showed an over 80% reduction in primary tumor growth upon rechallenge in contrast to controls. In summary, survivin-based DNA vaccination is effective against NB and the rational minigene design provides a promising approach to circumvent potentially hazardous effects of using full length antiapoptotic genes as DNA vaccines.

Eradication of CD19+ leukemia by targeted calicheamicin θ.

Children with relapsed and refractory acute lymphoblastic leukemia (ALL) still face a critical prognosis. We tested the hypothesis that targeted calicheamicin theta (θ) using an anti-CD19-immunoconjugate may provide an effective treatment strategy for CD19(+) ALL. Calicheamicin θ is a rationally designed prodrug of the natural enediyene calicheamicin γ, obtained by total synthesis. It offers the advantage of increased in vivo stability and 1000-fold higher antitumor potency over calicheamicin γ. First, we demonstrate efficacy of calicheamicin θ against primary pre-B leukemic cells and multidrug-resistant leukemia cell lines (IC(50) = 10(-9) to 10(-12) M). Second, conjugation of calicheamicin θ to an internalizing murine anti-CD19 monoclonal antibody was demonstrated to affect neither calicheamicin θ mediated cytotoxicity nor binding of the antibody to the target molecule. Third, anti-CD19-calicheamicin θ immunoconjugate revealed a maximum tolerated dose of 10 µg/kg and CD19-specific and long-lasting eradication of established leukemia was demonstrated in a xenograft model. Finally, we show that the antileukemic effect of anti-CD19-calicheamicin θ is mediated by induction of apoptosis proceeding through the caspase-mediated mitochondrial pathway. On the basis of these results, we conclude that anti-CD19-calicheamicin θ immunoconjugates may offer a novel and effective approach for the treatment of relapsed CD19(+) ALL.

Fractalkine (CX3CL1)- and interleukin-2-enriched neuroblastoma microenvironment induces eradication of metastases mediated by T cells and natural killer cells.

Fractalkine (FKN) is a unique CX3C chemokine (CX3CL1) known to induce both adhesion and migration of leukocytes mediated by a membrane-bound and a soluble form, respectively. Its function is mediated through CX3C receptor (CX3CR), which is expressed by T(H)1 immune cells including T cells and natural killer (NK) cells. FKN was shown to be expressed in >90% of 68 neuroblastoma samples as determined by cDNA microarray analysis. Here, we characterized the effect of FKN in the neuroblastoma microenvironment using a syngeneic model genetically engineered to secrete FKN. We show FKN-mediated migration, adhesion, and IFN-gamma secretion of immune effector cells, but limited antineuroblastoma activity, in vitro and in vivo. Therefore, we tested the hypothesis that a combined increase of FKN and interleukin-2 (IL-2) in the neuroblastoma microenvironment induces an effective antitumor immune response. For this purpose, IL-2 was targeted to ganglioside GD2, which is highly expressed on neuroblastoma tissue, using an anti-GD2 antibody IL-2 immunocytokine (ch14.18-IL-2). Only mice bearing FKN- and IL-2-enriched neuroblastoma tumors exhibited a reduction in primary tumor growth and a complete eradication of experimental liver metastases. The depletion of T cells and NK cells in vivo abrogated the effect, and these effector cells showed the highest cytolytic activity in vitro. Finally, only the FKN- and IL-2-enriched neuroblastoma microenvironment resulted in T-cell activation and the release of proinflammatory cytokines. In summary, we showed for the first time the immunologic mechanisms by which targeted IL-2 treatment of neuroblastoma with an FKN-rich microenvironment induces an effective antitumor response.

A rationally designed tyrosine hydroxylase DNA vaccine induces specific antineuroblastoma immunity.

Therapeutic vaccination against tumor antigens without induction of autoimmunity remains a major challenge in cancer immunotherapy. Here, we show for the first time effective therapeutic vaccination followed by suppression of established spontaneous neuroblastoma metastases using a tyrosine hydroxylase (TH) DNA minigene vaccine. We identified three novel mouse TH (mTH3) derived peptides with high predicted binding affinity to MHC class I antigen H2-K(k) according to the prediction program SYFPEITHI and computer modeling of epitopes into the MHC class I antigen binding groove. Subsequently, a DNA minigene vaccine was generated based on the expression vector pCMV-F3Ub encoding mutated ubiquitin (Gly(76) to Ala(76)) and mTH3. Prophylactic and therapeutic efficacies of this vaccine were established following oral delivery with attenuated Salmonella typhimurium SL7207. Only mice immunized with mTH3 were free of spontaneous liver metastases. This effect was clearly dependent on ubiquitin and high affinity of the mTH epitopes to MHC class I antigens. Specifically, we showed a crucial role for minigene expression as a stable ubiquitin-Ala(76) fusion peptide for vaccine efficacy. The immune response following the mTH3 DNA minigene vaccination was mediated by CD8(+) T cells as indicated by infiltration of primary tumors and TH-specific cytolytic activity in vitro. Importantly, no cell infiltration was detectable in TH-expressing adrenal medulla, indicating the absence of autoimmunity. In summary, we show effective therapeutic vaccination against neuroblastoma with a novel rationally designed TH minigene vaccine without induction of autoimmunity providing an important baseline for future clinical application of this strategy.

Primary ciliary dyskinesia associated with normal axoneme ultrastructure is caused by DNAH11 mutations.

Primary ciliary dyskinesia (PCD) is an inherited disorder characterized by perturbed or absent beating of motile cilia, which is referred to as Kartagener syndrome (KS) when associated with situs inversus. We present a German family in which five individuals have PCD and one has KS. PCD was confirmed by analysis of native and cultured respiratory ciliated epithelia with high-speed video microscopy. Respiratory ciliated cells from the affected individuals showed an abnormal nonflexible beating pattern with a reduced cilium bending capacity and a hyperkinetic beat. Interestingly, the axonemal ultrastructure of these respiratory cilia was normal and outer dynein arms were intact, as shown by electron microscopy and immunohistochemistry. Microsatellite analysis indicated genetic linkage to the dynein heavy chain DNAH11 on chromosome 7p21. All affected individuals carried the compound heterozygous DNAH11 mutations c.12384C>G and c.13552_13608del. Both mutations are located in the C-terminal domain and predict a truncated DNAH11 protein (p.Y4128X, p.A4518_A4523delinsQ). The mutations described here were not present in a cohort of 96 PCD patients. In conclusion, our findings support the view that DNAH11 mutations indeed cause PCD and KS, and that the reported DNAH11 nonsense mutations are associated with a normal axonemal ultrastructure and are compatible with normal male fertility.

Nutrient mixture including vitamin C, L-lysine, L-proline, and epigallocatechin is ineffective against tumor growth and metastasis in a syngeneic neuroblastoma model.

BACKGROUND: The replacement of established evidence-based cancer therapy protocols (mainstream therapy) by unevaluated complementary and alternative medicine (CAM) is a challenge in pediatric oncology. We tested the hypothesis that oral application of L-lysine and ascorbic acid (Lysin C Drink) in combination with epigallocatechin-gallate (EGCG) and amino-acids (Epican forte) is effective in a preclinical model of neuroblastoma. METHODS: Primary tumors and spontaneous metastases were induced in A/J mice by injection of NXS2 neuroblastoma cells. Mice were treated by daily oral gavage with L-lysine and ascorbic acid (Lysin C Drink) (equivalent to 150 mg ascorbic acid/day/mouse) (treatment A) or with EGCG plus ascorbic- and amino-acids (Epican forte) (9.2 mg/mouse) (treatment B). Treatment A was started in the prophylactic setting (7 days before tumor cell injection) as well as in the therapeutic setting (1 day after tumor cell inoculation). Finally, treatment B was evaluated alone and in combination with treatment A in the therapeutic setting. The effect on primary tumor growth and the development of spontaneous liver metastases was evaluated. RESULTS: L-lysine and ascorbic acid (Lysin C Drink) and EGCG plus ascorbic- and amino-acids (Epican forte) are ineffective in reduction of primary tumor growth and prevention of spontaneous liver metastases in this model. CONCLUSIONS: Neither a formal clinical development nor the use of these substances can be recommended for neuroblastoma.

Characterization of GD2 peptide mimotope DNA vaccines effective against spontaneous neuroblastoma metastases.

Disialoganglioside GD2 is an established target for immunotherapy in neuroblastoma. We tested the hypothesis that active immunization against the glycolipid GD2 using DNA vaccines encoding for cyclic GD2-mimicking decapeptides (i.e., GD2 mimotopes) is effective against neuroblastoma. For this purpose, two GD2 peptide mimotopes (MA and MD) were selected based on docking experiments to anti-GD2 antibody ch14.18 (binding free energy: -41.23 kJ/mol for MA and -48.06 kJ/mol for MD) and Biacore analysis (K(d) = 12.3 x 10(-5) mol/L for MA and 5.3 x 10(-5) mol/L for MD), showing a higher affinity of MD over MA. These sequences were selected for DNA vaccine design based on pSecTag2-A (pSA) also including a T-cell helper epitope. GD2 mimicry was shown following transfection of CHO-1 cells with pSA-MA and pSA-MD DNA vaccines, with twice-higher signal intensity for cells expressing MD over MA. Finally, these DNA vaccines were tested for induction of tumor protective immunity in a syngeneic neuroblastoma model following oral DNA vaccine delivery with attenuated Salmonella typhimurium (SL 7207). Only mice receiving the DNA vaccines revealed a reduction of spontaneous liver metastases. The highest anti-GD2 humoral immune response and natural killer cell activation was observed in mice immunized with the pSA-MD, a finding consistent with superior calculated binding free energy, dissociation constant, and GD2 mimicry potential for GD2 mimotope MD over MA. In summary, we show that DNA immunization with pSA-MD may provide a useful strategy for active immunization against neuroblastoma.

Fractalkine gene therapy for neuroblastoma is more effective in combination with targeted IL-2.

The induction of tumor protective immunity against neuroblastoma remains a major challenge for active immunotherapy. Fractalkine is a unique Th1 CX3C chemokine known to induce adhesion and migration of leukocytes mediated by both, a membrane-bound and soluble form, respectively. Here, we tested the hypothesis that chemokine gene therapy with fractalkine (FKN) induces an effective anti-neuroblastoma immune response amplified by targeted IL-2 using the anti-GD2 antibody ch14.18 fused with IL-2 (ch14.18-IL-2). For this purpose, NXS2 cells were genetically engineered to stably produce murine FKN (NXS2-FKN). Transcription and expression of the mFKN gene in tumor tissue of mice inoculated with NXS2-FKN cells were demonstrated in vivo. Importantly, mFKN exhibited a reduction in primary tumor growth and spontaneous liver metastases in syngenic A/J mice. This effect was boosted by targeted IL-2 using small non-curative doses of ch14-18-IL-2. The amplification of the FKN induced immune response was specific, since a non-specific antibody-IL-2 fusion protein ch225-IL-2 was ineffective. In summary, we demonstrated for the first time that chemokine gene therapy is amplified by targeted IL-2 suggesting a combination of both strategies as an adjuvant therapy for neuroblastoma.

Open randomized trial comparing the immunogenicity and safety of a new measles-mumps-rubella vaccine and a licensed vaccine in 12- to 24-month-old children.

BACKGROUND: A trivalent measles-mumps-rubella (MMR) vaccine (MMR Berna) has been developed with a new mumps component, BBM-18, to replace a previously licensed MMR vaccine containing the Rubini mumps strain. Previous studies showed Rubini to confer insufficient long term protection against mumps infection. This study compared the immunogenicity and safety of MMR Berna, which is produced entirely in human diploid cells, with those of the licensed vaccine M-M-RVax (Merck & Co.). METHODS: We vaccinated 467 subjects, 12-24 months of age, in an open, randomized (1:1), phase II, multicenter study. Antibody titers were determined for each vaccine component with a plaque neutralization test (PNT) and a commercial enzyme-linked immunosorbent assay. Solicited local and systemic reactions were recorded in subject diaries for 6 weeks after vaccination. RESULTS: Seroconversion rates 6 to 8 weeks after vaccination for measles and rubella were statistically comparable for the 2 vaccines. However, mumps seroconversion rates were highly assay dependent, with significant differences being measured with the enzyme-linked immunosorbent assay (Berna, 77.4%; Merck, 91.3%; P < 0.001) but not the PNT (Berna, 84.8%; Merck, 87.6%; P = 0.42). The overall rate of systemic reactions was lower in the MMR Berna group (36.8% versus 45.9%; P < 0.05), including a significantly lower rate of fever of >38 degrees C (37.2% versus 51.8%; P < 0.01). CONCLUSIONS: MMR Berna was statistically noninferior to M-M-RVax with respect to seroconversion rates, and the BBM-18 strain elicited a level of functional antimumps antibodies comparable to the Jeryl Lynn strain, as measured with the PNT. Overall, MMR Berna was better tolerated than the comparison vaccine, particularly with respect to the frequency of fever.

Teaching vaccine safety communication to medical students and health professionals.

Not only the general public, but also those studying to become health professionals, are struggling to keep up with a growing body of evidence and increasingly complex information about the many different types of vaccines available to date. At the same time, a number of increasingly complex subjects of study are competing for their attention during undergraduate and graduate education. In many medical school curricula in German-speaking countries, the subject of vaccines has been entirely omitted, or is regarded a minor subtopic. During the studies, most medical school curricula in German-speaking countries do not offer obligatory courses and/ or hands-on training vaccinology in vaccination. In Germany, private pediatricians administer the majority of immunizations. Even during postgraduate training programs in pediatrics, which are largely hospital-based, vaccinations are rarely a topic, and vaccinology remains a "hobby" and a "field without lobby" lacking specific certification requirements. Studies of acceptance of vaccines among health professionals and medical students have shown that many may still have their own doubts and uncertainties about vaccines revealing a number of unanswered questions during their studies and postgraduate training.

A design thinking approach to effective vaccine safety communication.

The highly complex and controversial topic of vaccine safety communication warrants innovative, user-centered solutions that would start with gaining mutual respect while taking into account the needs, concerns and underlying motives of patients, parents and physicians. To this end, a non-profit collaborative project was conducted by The Vienna Vaccine Safety Initiative, an international think tank aiming to promote vaccine safety research and communication, and the School of Design Thinking in Potsdam, Germany, the first school for innovation in Europe. The revolutionary concept of the Design Thinking approach is to group students in small multi-disciplinary teams. As a result they can generate ground-breaking ideas by combining their expertise and different points of view. The team agreed to address the following design challenge question: "How might we enable physicians to encourage parents and children to prevent infectious diseases?" The current article describes, step-by step, the ideation and innovation process as well as first tangible outcomes of the project.

Pulmonary symptoms in Kawasaki disease.

The diagnosis of Kawasaki disease is based on 6 clinical criteria, 5 of which must be fulfilled. The presence of uncommon symptoms in addition to the classic criteria can be as misleading as the lack of common ones. Here we report 2 infants with marked pulmonary symptoms in the course of Kawasaki disease who were initially diagnosed with pneumonia.

Comparison of immunogenicity and tolerability of a virosome-adjuvanted and a split influenza vaccine in children.

OBJECTIVE: To compare the immunogenicity and safety of a virosome-adjuvanted influenza vaccine (Inflexal V; Berna Biotech, Berne, Switzerland) and a split influenza vaccine (Fluarix; GlaxoSmithKline Biologicals, Rixensart, Belgium) in children. SUBJECTS AND METHODS: The subjects, 453 children ages 6 to 71 months, were stratified into primed and unprimed and age groups (6 to 35 and 36 to 71 months) and then randomized 1:1 to receive virosome-adjuvanted (n = 224) or split influenza vaccine (n = 229), a half or full dose was given intramuscularly according to age. Unprimed children received a second dose after 4 weeks. Blood samples (n = 326) collected pre-and 28 days postvaccination were analyzed by hemagglutination inhibition test. Safety assessments were made at baseline and follow-up visits by the investigators and by parents for the 4 days after vaccinations. RESULTS: Both vaccines induced an effective immune response. Seroconversion rates (>4-fold titer rise) against the WHO recommended strains A/New Caledonia (H3N2), A/Moscow (H1N1) and B/Hongkong (B) were 80.1, 66.0 and 90.4% for the virosome-adjuvanted and 75.9, 62.9 and 89.4% for the split influenza vaccine, respectively. Unprimed children's seroconversion rates for H3N2 were significantly higher (P = 0.02) for the virosome-adjuvanted (88.8%) than for split influenza vaccine (77.5%). Seroprotection rates (titer of > 40) for H3N2, H1N1 and B, respectively, were 87.8, 80.1 and 90.4% after vaccination with the virosome-adjuvanted vaccine and 82.9, 78.2 and 89.4% after the split influenza vaccine. Unprimed children's seroprotection rate was significantly higher (P = 0.03) for H3N2 after the virosome-adjuvanted (88.8%) than those for the split influenza vaccine (78.3%). Equivalent geometric mean titer fold increases were evident for both vaccines. No serious adverse events were seen. Pain/ tenderness, redness and swelling/induration was found in 25.4, 11.2 and 8.9% for the virosome-adjuvanted vaccine and in 24.0, 9.2 and 6.1% for the split influenza vaccine, respectively. The rates of fever, malaise/irritability and shivering was 6.3, 11.6 and 2.7% for the virosome-adjuvanted vaccine and 8.3, 11.8 and 2.6% for the split influenza vaccine, respectively. CONCLUSIONS: The virosome-adjuvanted influenza vaccine showed greater immunogenicity over the split influenza vaccine in unprimed children and showed a trend toward better immunogenicity in the rest of the study population. Both vaccines were well-tolerated.

Angiogenesis, views and news. The 93rd annual meeting of the American Association for Cancer Research. April 6-10 2002, Moscone Convention Center, San Francisco, USA.

The 93rd Annual Meeting of the American Association of Cancer Research was held in San Francisco, CA, USA. It was one of the largest conferences of its kind covering all aspects of cancer research with 6000 scientific presentations over a period of 5 days. The following meeting highlights are focused on a few selected developments in the field of tumour-induced angiogenesis, attempting a synthesis between educational sessions and original scientific presentations. Two important shifts in paradigms were reported at that meeting involving the biology of tumour-induced angiogenesis. Firstly, the generation of new blood vessels was demonstrated to dramatically depend on bone marrow-derived circulating endothelial precursor cells, thereby supplementing existing concepts of vessel generation by migration and proliferation of pre-existing mature endothelial cells. Secondly, the genetic stability of endothelial cells circumventing resistance to antiangiogenic therapy was challenged by the observation of resistance to hypoxia, which developed in tumour cells following antiangiogenic therapy. Both aspects are discussed in the following chapters with respect to their possible impact on the development of therapeutic strategies involving angiogenesis inhibition.