Hans-Jürgen Laws

Girls homozygous for an IL-2–inducible T cell kinase mutation that leads to protein deficiency develop fatal EBV-associated lymphoproliferation

The fatal immune dysregulation that sometimes follows EBV infection in boys has been linked to mutations in two X chromosome-encoded genes, SLAM-associated protein (SAP) and X-linked inhibitor of apoptosis (XIAP). In this study we describe 2 girls from a consanguineous Turkish family who died after developing severe immune dysregulation and therapy-resistant EBV-positive B cell proliferation following EBV infection. SNP array-based genome-wide linkage analysis revealed IL-2-inducible T cell kinase (ITK) as a candidate gene for this immunodeficiency syndrome. Both girls harbored a homozygous missense mutation that led to substitution of a highly conserved residue (R335W) in the SH2 domain of ITK. Characteristics of ITK deficiency in mouse models, such as absence of NKT cells and high levels of eomesodermin in CD8+ cells, were seen in either one or both of the girls. Two lines of evidence suggested that R335W caused instability of the ITK protein. First, in silico modeling of the mutant protein predicted destabilization of the SH2 domain. Additionally, Western blot analysis revealed that, unlike wild-type ITK, the R335W mutant was nearly undetectable when expressed in 293 T cells. Our results suggest that ITK deficiency causes what we believe to be a novel immunodeficiency syndrome that leads to a fatal inadequate immune response to EBV. Because ITK deficiency resembles EBV-associated lymphoproliferative disorders in boys, we suggest that this molecular cause should be considered during diagnosis and treatment.

Quantitative Detection of Norovirus Excretion in Pediatric Patients With Cancer and Prolonged Gastroenteritis and Shedding of Norovirus

Although chronic courses of norovirus infection have been described in immunocompromised patients, little is known about noroviral shedding and correlation with clinical symptoms in these patients. In this report, the quantitative courses of norovirus excretion in nine pediatric patients with hematologic and oncologic disorders and prolonged gastroenteritis were investigated. In a retrospective study multiple fecal samples from nine pediatric cancer patients were examined by a one‐step real‐time PCR. Clinical data of the patients were reviewed and virological data were correlated with clinical symptoms. All nine patients presented with prolonged illness and prolonged noroviral shedding. Vomiting and diarrhea were associated with high norovirus concentrations and norovirus excretion declined slowly in the patients. Retrospectively, initial PCR‐testing for norovirus was performed with a median of 7 days after onset of symptoms. This finding hints at the difficulty of obtaining early diagnosis of the infection in these children. The patients were shedding high norovirus concentration over a long period of time. Results of sequential quantitative PCR‐testing for norovirus correlated with clinical symptoms. Both clinical symptoms and quantitative PCR‐testings help to define the severity of norovirus infection and to estimate the risk for transmission. To prevent the spread of the disease, usage of virocidal disinfectants and isolation procedures should be maintained as long as patients are positive for noroviruses. Since vomiting is frequent in pediatric patients with oncological conditions, a screening program for rapid detection of norovirus infection in this group of patients should be considered. J. Med. Virol. 80:1461–1467, 2008.

High dose therapy for patients with primary multifocal and early relapsed Ewing's tumors : results of two consecutive regimens assessing the role of total-body irradiation

PURPOSE Risk stratification of metastatic and relapsed Ewings tumors (ETs) has been a matter of debate during the last decade. Patients with bone or bone marrow metastases or early or multiple relapses constitute the worst risk group in ET and have a poorer prognosis than patients with primary lung metastases or late relapses. In this article, the results of the present Meta European Intergroup Cooperative Ewing Sarcoma Study (MetaEICESS) (tandem melphalan/etoposide [TandemME]) were compared with the result of the previous study (hyper melphalan/etoposide [HyperME]), both at 5 years, in a patient population within the same high-risk stratum to determine toxicity. PATIENTS AND METHODS Among 54 eligible patients, 26 were treated according to the HyperME protocol, and 28 were treated according to TandemME protocol. Patients received six cycles of the Cooperative Ewing Sarcoma Study treatment in HyperME and six cycles of the EICESS treatment in TandemME as induction chemotherapy. Patients also received involved-compartment irradiation for local intensification and myeloablative systemic intensification consolidation with hyperfractionated total-body irradiation (TBI) combined with melphalan/etoposide in HyperME or two times the melphalan/etoposide in TandemME followed by autologous stem-cell transplantation. RESULTS The event-free survival (EFS) rate +/- SD in HyperME and TandemME was 22% +/- 8% and 29% +/- 9%, respectively. The dead of complication rate was 23% in HyperME and 4% in TandemME. CONCLUSION TandemME offers a decent, albeit still not satisfactory, rate of long-term remissions in most advanced ETs (AETs), with short-term treatment and acceptable toxicity. TBI was not required to maintain EFS level in this setting but was associated with a high rate of toxic death. Future prospective studies in unselected patients are warranted to evaluate high-dose therapy in an unselected group of patients with AET.

A Toll-like receptor 2-integrin beta(3) complex senses bacterial lipopeptides via vitronectin

Toll-like receptor 2 (TLR2) initiates inflammation in response to bacterial lipopeptide (BLP). However, the molecular mechanisms enabling the detection of BLP by TLR2 are unknown. Here we investigated the interaction of BLP with human serum proteins and identified vitronectin as a BLP-recognition molecule. Vitronectin and its receptor, integrin β3, were required for BLP-induced TLR2-mediated activation of human monocytes. Furthermore, monocytes from patients with Glanzmann thrombasthenia, which lack integrin β3, were completely unresponsive to BLP. In addition, integrin β3 formed a complex with TLR2 and this complex dissociated after BLP stimulation. Notably, vitronectin and integrin β3 coordinated responses to other TLR2 agonists such as lipoteichoic acid and zymosan. Our findings show that vitronectin and integrin β3 contribute to the initiation of TLR2 responses.

High-dose chemotherapy with autologous stem cell rescue in children with nephroblastoma

Children with Wilms tumor who have a particular risk of failure at relapse or at primary diagnosis were treated with high-dose chemotherapy (HDC) and autologous peripheral blood stem cell rescue in order to improve their probability of survival. From April 1992 to December 1998, 23 evaluable patients received HDC within the German Cooperative Wilms Tumor Studies. Nineteen were given melphalan, etoposide and carboplatin (MEC); the others received different regimens. The dose of carboplatin was adjusted according to renal function. Indications for HDC were high-risk relapse in 20 patients, bone metastases in two patients and no response in one patient. Fourteen of 23 patients are alive after a median observation time of 41 months, 11 of 14 in continuous complete remission, three in CR after relapse post HDC. The estimated survival and event-free survival for these patients are 60.9% and 48.2%. Twelve children relapsed after HDC; nine of them died within 12 months and three are surviving from 20 to 33 months after relapse. The main toxicities were hematologic, mucositis and renal (tubular dysfunction; intermittent hemodialysis in one patient). There were no toxic deaths. About half of the children suffering from Wilms tumor with very unfavorable prognostic factors survive disease-free after HDC for over 3 years. Besides hematological toxicity, mucositis and infections, renal function is at risk during HDC. With dose adjustment on glomerular filtration rate, however, no permanent renal failure was observed.

Prospective, Comprehensive, and Effective Viral Monitoring in Children Undergoing Allogeneic Hematopoietic Stem Cell Transplantation

Major advances in the monitoring and treatment of viral infections after hematopoietic stem cell transplantation (HSCT) have been achieved over the last decade. The appropriate extent of viral monitoring and antiviral therapy remains controversial, and reports in pediatric patients receiving allogeneic unmanipulated hematopoietic stem cells (HSCs) are sparse. A total of 40 pediatric patients who underwent HSCT with either peripheral blood stem cells (PBSCs, n = 30) or bone marrow (BM; n = 10) were prospectively monitored every week for viral DNAemia (VDNA) by simultaneous detection of cytomegalovirus (CMV), Epstein-Barr virus (EBV), human herpesvirus 6 (HHV6), human adenovirus (ADV), and polyoma BK virus (BKV) using real-time TaqMan polymerase chain reaction (PCR). All patients received prophylactic acyclovir and preemptive ganciclovir (GCV) when 500 copies/microg DNA (EBV/HHV6) or >1 copy/microg DNA (CMV) were detected on 2 consecutive measurements. VDNA occurred in 25 of 40 recipients (CMV, 11/40 patients [28%]; EBV, 19/40 [48%]; HHV6, 2/40 [5%]; ADV/BKV, 1/40) and was found exclusively after neutrophil engraftment and in most cases up to day +100. Recurrent VDNA (P = .028) and (readily treatable) viral disease (P = .003) were observed predominantly in patients suffering from nonmalignant diseases, a cohort characterized by delayed lymphocyte engraftment. VDNA occurred more frequently in HLA-mismatched HSCT and in the 24 of 40 patients receiving antithymocyte globulin (ATG). The incidence of EBV, but not that of CMV, was increased in the ATG group. Yet, in these patients, viral loads of both EBV and CMV were higher, but with prompt initiation of preemptive GCV, no posttransplantation lymphoproliferative disorder or other life-threatening morbidities occurred. HHV6 was typically detected at low viral loads (<10(2) copies/microg DNA), with only 5% of HSC recipients fulfilling our HHV6 criteria for triggering GCV treatment. In multivariate analysis, ATG treatment, HLA mismatch, recipient CMV seropositivity, and stem cell source, but not severe acute graft-versus-host disease were identified as independent risk factors for VDNA. This comprehensive viral monitoring program with defined thresholds for initiation of preemptive GCV effectively prevents the development of critical viral disease, even in high-risk patients receiving ATG.

The German national registry for primary immunodeficiencies (PID)

In 2009, a federally funded clinical and research consortium (PID–NET, http://www.pid‐net.org) established the first national registry for primary immunodeficiencies (PID) in Germany. The registry contains clinical and genetic information on PID patients and is set up within the framework of the existing European Database for Primary Immunodeficiencies, run by the European Society for Primary Immunodeficiencies. Following the example of other national registries, a central data entry clerk has been employed to support data entry at the participating centres. Regulations for ethics approvals have presented a major challenge for participation of individual centres and have led to a delay in data entry in some cases. Data on 630 patients, entered into the European registry between 2004 and 2009, were incorporated into the national registry. From April 2009 to March 2012, the number of contributing centres increased from seven to 21 and 738 additional patients were reported, leading to a total number of 1368 patients, of whom 1232 were alive. The age distribution of living patients differs significantly by gender, with twice as many males than females among children, but 15% more women than men in the age group 30 years and older. The diagnostic delay between onset of symptoms and diagnosis has decreased for some PID over the past 20 years, but remains particularly high at a median of 4 years in common variable immunodeficiency (CVID), the most prevalent PID.

Diagnostic and therapeutic implications of neurological complications following paediatric haematopoietic stem cell transplantation

Neurological complications are a relevant cause of morbidity and mortality after haematopoietic stem cell transplantation (SCT). We retrospectively analysed neurological complications of 165 paediatric patients who underwent SCT between 1996 and 2003. In all, 111 (67%) transplantations were allogeneic and 54 (33%) transplantations were autologous. Post-SCT neurological complications were seen in 24% of patients. They were seen in six children after autologous SCT and in 11 and 23 cases after allogeneic-related and -unrelated SCT. Neurological symptoms occurred between day +22 and +912 after transplantation and were classified into two groups. The first group (n=21) offered non-repetitive symptoms lasting less than 24 h without any cerebral imaging and cerebrospinal fluid(CSF) abnormalities. The second group (n=19) was characterized by progressive neurological symptoms, pathological MRI findings and/or abnormal results in CSF. Those with a progressive clinical course resulted from infections (n=10), drug toxicity (n=5), cerebrovascular events (n=2) and the central nervous system (CNS) relapse of the underlying disease (n=2). In particular, cerebral aspergillosis and toxoplasmosis after allogeneic unrelated SCT are a major challenge and are associated with a high mortality. In conclusion, our data suggest that patients presenting with progressive neurological symptoms after SCT require prompt diagnostic procedures and initiation in antimicrobial therapy in case of any findings suggestive of CNS infection.

Increased risk for invasive pneumococcal diseases in children with acute lymphoblastic leukaemia.

Asplenia and other conditions of immunodeficiency are established risk factors for invasive pneumococcal disease (IPD). There are no current data available on the risk of IPD in children with acute lymphoblatic leukaemia (ALL), the most common type of childhood malignancy. This study combined data from a nation‐wide surveillance for IPD and the German childhood cancer registry, and showed that children with ALL carry a more than 10‐fold higher risk for IPD than the general paediatric population. As a substantial proportion of IPD occurs during maintenance chemotherapy, children with ALL may represent candidates for the evaluation of prophylactic interventions including vaccination.

Serial evaluation of the oncological pediatric risk of mortality (O-PRISM) score following allogeneic bone marrow transplantation in children

The O-PRISM score was introduced for risk assessment in children transferred to intensive care following BMT. The aim of this study is to determine the prognostic value of a serial evaluation of the O-PRISM score. Ninety-three children, 58 allogeneic-related and 35 unrelated BMT, were evaluated. At weekly intervals, the O-PRISM was calculated based on the standard PRISM score and the three additional variables CRP, GVHD and hemorrhage. Overall survival was 0.51 ± 0.05 (48/93 patients). Seventeen children died of recurrent disease and 28 of BMT-related complications. High O-PRISM scores significantly correlated with adverse outcome. The relative risks of DOC of patients with scores ⩾10 compared to patients with lower scores were: day 0: 3.9 (95% confidence-interval: 1.1–13.7, P = 0.02), day 7: 2.0 (0.7–6.2, P = 0.20), day 14: 5.2 (1.9–14.0, P = 0.001), day 21: 5.6 (1.9–16.5, P = 0.001), day 28: 11.5 (3.8–100.9, P < 0.001), day 35: 7.3 (1.9–27.7, P = 0.001). As early as day 0, children with scores ⩾10 points showed a higher cumulative incidence of DOC than patients with lower scores (0.69 ± 0.15 vs 0.27 ± 0.05, P = 0.02). The O-PRISM score represents a useful clinical parameter for serial risk assessment following BMT. As it indicates fatal events early, it may be helpful for parent information and even more for the early establishment of intensified supportive treatment. The O-PRISM score may therefore be a valuable parameter for the evaluation of different strategies for BMT and supportive treatment.Bone Marrow Transplantation (2002) 29, 383–389. doi:10.1038/sj.bmt.1703384