Immunological recovery following HLA-matched CD3+ TCR αß+/CD19+ depleted hematopoietic stem cell transplantation in children.

BACKGROUND: Allogeneic hematopoietic stem cell transplantation (HSCT) is a potentially curative option for children with both malignant and nonmalignant diseases. T-cell depletion techniques may result in reduced transplant-related mortality compared with unmanipulated grafts due to a lower incidence of GvHD. METHODS: Immune recovery and outcome were analyzed in a cohort of 23 patients with malignant and nonmalignant diseases who received CD3+TCRαß+ T- and B-cell-depleted allografts from matched donors after reduced-intensity or myeloablative conditioning. The median number of CD34+, CD3+TCRαß+, and CD19+B-cells infused was 12.7 × 106 /kg, 16.8 × 103 /kg, and 96 × 103 /kg bodyweight. RESULTS: With a median follow-up of 36 (range 1-73) months, overall survival and disease-free survival at 3 years were 65.2% and 60.8%. Eight patients died, six due to the underlying disease and two of extended visceral cGvHD. Immune reconstitution, disease-free, and overall survivals were similar compared with a historical cohort of 23 patients transplanted with matched unmanipulated bone marrow. A significant lower rate of higher grade (III-IV) aGvHD was observed in the manipulated HSCT group (8.7% vs. 26%; p = 0.001), whereas the incidence of cGvHD was equal. CONCLUSIONS: Our data suggest that this graft manipulation strategy could be a safe and effective alternative to conventional HSCT techniques in matched donors.

Lymphopenia in primary Sjögren's syndrome is associated with premature aging of naïve CD4+ T cells.

OBJECTIVE: To investigate peripheral lymphopenia, a frequent finding in primary Sjögren's syndrome (pSS) associated with higher disease activity and increased mortality. METHODS: Prospective, cross-sectional study of consecutive patients with pSS (n = 66) and healthy controls (n = 181). Lymphocyte subsets were analysed by flow cytometry, naïve (CD45RA+) and memory (CD45RO+) CD4+ T cells were purified by MACS technology. In vitro proliferation and senescence-associated ß-galactosidase (SABG) were assessed by flow cytometry. Telomere length and TCR excision circles (TREC) were measured by real-time PCR. Telomerase activity was analysed according to the telomeric repeat amplification protocols (TRAP). RESULTS: In pSS, lymphopenia mainly affected naïve CD4+ T cells. We noted a lower frequency of proliferating naïve CD4+ T cells ex vivo and decreased homeostatic proliferation in response to IL-7 stimulation in vitro. Furthermore, naïve CD4+ T cells exhibited signs of immune cell aging including shortened telomeres, a reduction in IL-7R expression and accumulation of SABG. The senescent phenotype could be explained by telomerase insufficiency and drastically reduced levels of T-cell receptor excision circles (TRECs), indicating a history of extensive post-thymic cell division. TRECs correlated with the number of naïve CD4+ T cells linking the extend of earlier proliferation to the inability to sustain normal cell numbers. CONCLUSION: In pSS, evidence for increased proliferation of naïve CD4+ T cells earlier in life is associated with a senescent phenotype unable to sustain homeostasis. The lack of naïve CD4+ T cells forms the basis of lymphopenia frequently observed in pSS.

Low incidence of symptomatic osteonecrosis after allogeneic HSCT in children with high-risk or relapsed ALL - results of the ALL-SCT 2003 trial.

Osteonecrosis (ON) was prospectively assessed in 557 children and adolescents in the Berlin-Frankfurt-Münster Stem Cell Transplantation in children with acute lymphoblastic leukaemia 2003 trial. Median age at haematopoietic stem cell transplantation (HSCT) was 10·3 years (range 0·5-26). Cumulative incidence of symptomatic ON (sON) was 9% at 5 years (standard deviation 1%), median time from HSCT to diagnosis of sON was 12·4 months (range 1-126). Multivariate analysis identified age at HSCT [10-15 years vs. <10 years: hazard ratio (HR) 3·73, P = 0·009; >15 years vs. <10 years: HR 5·46, P = 0·001], diagnosis of sON prior to HSCT and chronic graft-versus-host disease (yes versus no: HR 2·696, P = 0·015) as significant independent risk factors for the development of sON.

Malignancy and chemotherapy induced haemophagocytic lymphohistiocytosis in children and adolescents-a single centre experience of 20 years.

Haemophagocytic lymphohistiocytosis (HLH) is a possibly life-threatening syndrome of immune dysregulation and can be divided into primary (hereditary) and secondary forms (including malignancy-associated HLH (M-HLH)). We retrospectively analysed epidemiological, clinical, virological and laboratory data from patients with M-HLH treated at our department between 1995 and 2014. Out of 1.706 haemato-/oncologic patients treated at our department between 1995 and 2014, we identified 22 (1.29%) patients with secondary HLH (1.3-18.0, median 10.1 years; malignancy induced n = 2; chemotherapy induced n = 20). Patients with acute myeloblastic leukaemia (AML) developed HLH significantly more often than patients with acute lymphoblastic leukaemia (ALL) (10/55, 18.2% vs. 6/148, 4.1%, p = 0.0021). As possible viral triggers, we detected BKV (53.8% of the tested patients), HHV-6 (33.3%), EBV (27.8%), CMV (23.5%), ADV (16.7%) and PVB19 (16.7%) significantly more frequently than in haemato-/oncologic patients without HLH. Despite lacking evidence of concurrent bacterial infection, C-reactive protein (CRP) and procalcitotnin (PCT) were elevated in 94.7 and 77.7% of the patients, respectively. Ferritin and sIL2R were markedly elevated in all patients. HLH-associated mortality significantly (p = 0.0276) decreased from 66.6% (1995-2004) to 6.25% (2005-2014), suggesting improved diagnostic and therapeutic management. Awareness of HLH is important, and fever refractory to antibiotics should prompt to consider this diagnosis. Elevated ferritin and sIL2R seem to be good markers, while inflammatory markers like CRP and PCT are not useful to discriminate viral triggered HLH from severe bacterial infection. Re-/activation of several viruses may play a role as possible trigger.

Premature senescence of T-cell subsets in axial spondyloarthritis.

OBJECTIVE: To investigate the possible occurrence of early thymic failure and premature senescence of naïve and memory T-cells in patients with axial spondyloarthritis (aSpA). METHODS: Prospective, cross-sectional study of consecutive patients with aSpA (n=51), rheumatoid arthritis (RA, n=51) and healthy controls (HCs, n=50). Demographic, clinical and laboratory parameters were collected in all patients and we isolated naïve (CD45RA(+)) and memory (CD45RO(+)) CD4(+) and CD8(+) T-cell subsets by MACS technology. T-cell receptor rearrangement excision circle (TREC) and telomere length were measured by real-time PCR. We used TRECs as a surrogate for thymus function and telomere length as an indicator of cellular senescence. Telomerase activity was analysed with the Telomeric Repeat Amplification Protocols. RESULTS: We observed a premature decline of thymic output in patients with aSpA and patients with RA compared with HCs as indicated by a reduction of TREC levels in naive T-cells (aSpA: age adjusted regression coefficient (regcoeff) for CD4(+)CD45RA(+) T-cells -2.566, p=0.023; RA regcoeff=-2.844, p=0.008). Telomere length of all CD4(+) and CD8(+) T-cell subsets was reduced in young patients with aSpA compared with HCs, whereas data for patients with RA were comparable with HCs. Telomerase activity was inversely correlated with telomere length in HCs (correlation coefficient (corcoeff)=-0.532, p<0.001) but not in patients with aSpA (corcoeff=-0.056, p=0.697) and RA (corcoeff=-0.003, p=0.982). CONCLUSIONS: Our data indicate an age-inappropriate shrinkage of thymic output, an inappropriate shortening of telomeres in young patients with aSpA and an impaired telomerase enzyme in patients with aSpA and RA.

Successful Unrelated Stem Cell Transplantation in an Infant With Congenital Acute Myelogenous Leukemia FAB M5 Showing Massive Cutaneous Infiltrations--A Challenging Multidisciplinary Approach.

The multidisciplinary management of a male neonate presenting with congenital acute myelogenous leukemia of monoblastic phenotype is reported using conventional chemotherapy, high dose conditioning, and matched unrelated donor stem cell transplantation. These therapies were combined to add a graft versus leukemia effect to the treatment. Although chimerism studies showed a decrease of donor white blood cells, T-cells remained stable of allogeneic origin. We hypothesize that a continuous graft versus leukemia effect results in minimal residual disease negativity for now more than 18 months since stem cell transplantation.

Long-term Remission in a Female With Multiple Relapsed Juvenile Granulosa Cell Tumor.

A 4 ½-year-old female was diagnosed with ovarian juvenile granulosa cell tumor stage IA. After complete tumor resection she received 4 courses of chemotherapy due to unfavorable histopathologic features (high mitotic index, high microvessel density, blood vessel invasion). One year after diagnosis, she experienced paraaortic lymph node relapse treated with surgery, local radiotherapy, and conventional and high-dose chemotherapy. A second, paratracheal lymph node relapse 7 months later necessitated surgical removal and radiotherapy. Subsequently an adjuvant antiangiogenesis-based treatment including paclitaxel, bevacizumab, thalidomide, and pegylated interferon was initiated and continued for 2 years. The female is now in third complete remission 6 years after second relapse.

Sirolimus for the treatment of children with various complicated vascular anomalies.

Vascular anomalies include a heterogeneous group of disorders that are categorized as vascular tumors or vascular malformations. Treatment options include resection, embolization, laser therapy, and sclerotherapy or medical treatment such as propranolol, steroids, interferon, and cytostatic chemotherapy. Mammalian target of rapamycin seems to play a key role in the signal pathway of angiogenesis and subsequently in the development of vascular anomalies. Recently, the successful use of sirolimus has been reported in children with lymphatic malformations and kaposiform hemangioendotheliomas. We report on six patients with different vascular anomalies (kaposiform hemangioendothelioma n = 2, combined lymphatico-venous malformation n = 2, pulmonary lymphangiectasia n = 1, and orbital lymphatic malformation n = 1) who were treated with peroral sirolimus. Three of the children initially presented with a Kasabach-Merrit phenomenon. Median duration of treatment was 10 months; two children are still on treatment. Three children each achieved complete and partial remission. Kasabach-Merrit phenomenon resolved within 1 month in all patients. Treatment with sirolimus was tolerated well; only mild reversible leukopenia was observed. CONCLUSION: Sirolimus proved to be effective in children with complicated lymphatic or lymphatico-venous malformations and kaposiform hemangioendotheliomas. Treatment was tolerated well with acceptable side effects. The optimum length of treatment and possible long-term side effects have to be evaluated. WHAT IS KNOWN: • Vascular anomalies including vascular tumors and vascular malformations may lead to life-threatening conditions.• Some patients are refractory to established treatment and/or are not available for local invasive procedures. WHAT IS NEW: • We reviewed the literature focusing treatment of vascular anomalies inc hildren and adolescents.• Our data support recent studies that sirolimus is an effective treatment option in patients with complicated vascular tumors andmalformations

A novel immunodeficiency syndrome associated with partial trisomy 19p13.

BACKGROUND: Subtelomeric deletions and duplications may cause syndromic disorders that include features of immunodeficiency. To date, no phenotype of immunological pathology has been linked to partial trisomy 19. We report here on two unrelated male patients showing clinical and laboratory signs of immunodeficiency exhibiting a duplication involving Chromosome 19p13. METHODS: Both patients underwent a detailed clinical examination. Extended laboratory investigations for immune function, FISH and array comparative genome hybridization (CGH) analyses were performed. RESULTS: The reported patients were born prematurely with intrauterine growth retardation and share clinical features including neurological impairment, facial dysmorphy and urogenital malformations. Array CGH analyses of both patients showed a largely overlapping terminal duplication affecting Chromosome 19p13. In both affected individuals, the clinical course was marked by recurrent severe infections. Signs of humoral immunodeficiency were detected, including selective antibody deficiency against polysaccharide antigens in patient 1 and reduced IgG1, IgG3 subclass levels and IgM deficiency in patient 2. Class-switched B memory cells were almost absent in both patients. Normal numbers of T cells, B cells and natural killer cells were observed in both boys. Lymphocytic proliferation showed no consistent functional pathology, however, function of granulocytes and monocytes as assessed by oxidative burst test was moderately reduced. Moreover, natural killer cytotoxicity was reduced in both patients. Immunoglobulin substitution resulted in a decreased number and severity of infections and improved thriving in both patients. CONCLUSIONS: Partial trisomy 19p13 represents a syndromic disorder associating organ malformation and hitherto unrecognised immunodeficiency.

Amphotericin B transfer to CSF following intravenous administration of liposomal amphotericin B.

OBJECTIVES: Although amphotericin B (AmB) and its lipid formulations are used for the treatment of fungal infections of the CNS, the kinetics of AmB in the CSF after intravenous administration of liposomal amphotericin B (LAmB) are not well characterized. PATIENTS AND METHODS: From 14 paediatric haemato-oncological patients (aged 0.4-19.5 years, median 7.6 years), we obtained 30 CSF samples by means of routine punctures (performed for intrathecal treatment of the underlying diseases) at different timepoints after the prophylactic intravenous infusion of LAmB (AmBisome, 3 mg/kg/day). Concurrent serum samples were obtained to calculate the transfer rates. An HPLC method was used for AmB detection. RESULTS: CSF levels of AmB 1-100 h after the intravenous infusion of LAmB were between 10 and 120 ng/mL, except in one case with a level of 529 ng/mL. Concurrent serum levels were about 1000-fold higher, ranging between 3 and 75 µg/mL. CSF levels did not show a clear time-dependent concentration profile, but remained at a steady-state for longer than 48 h after infusion. The transfer rate ranged from 0.02% to 0.92% (median 0.13%) and correlated significantly (r=0.801, P<0.001) with increasing time after infusion. CONCLUSIONS: After the intravenous administration of LAmB, AmB CSF levels were low, confirming published animal data. CSF levels remained at a steady-state level for longer than 48 h. As indicated by published post mortem data, higher levels in brain tissue, which would be necessary for the successful treatment of CNS infections, might be possible.

Unrelated CD3/CD19-depleted peripheral stem cell transplantation for Hurler syndrome.

For patients with mucopolysaccharidosis type IH (MPS1-H; Hurler syndrome), early allogeneic hematopoietic stem cell transplantation (HSCT) is the treatment of choice. One boy and one girl aged 20.5 and 22 months, respectively, with MPS1-H received a conditioning regimen consisting of thiotepa, fludarabine, treosulfan, and ATG. Grafts were peripheral blood stem cells from unrelated donors (10/12 and 11/11 matched), that were manipulated by CD3/CD19 depletion and contained 20.3 and 28.2 × 10(6) CD34+ cells/kg body weight, respectively. Both patients achieved stable hematopoietic engraftment and stable donor chimerism. Neither acute or chronic graft-versus-host disease (GVHD) nor other severe transplant-related complications occurred. At a follow-up of 48 and 37 months, both patients are alive and well with normal levels of α-L-iduronidase and have made major neurodevelopmental progress. Treosulfan-based conditioning offers the advantage of reduced toxicity; the use of unrelated CD3/CD19-depleted peripheral stem cell grafts allows transfusion of high CD34+ cell numbers together with a "tailored" number of CD3+ cells as well as engraftment facilitating cells in order to achieve rapid hematopoietic engraftment while reducing the risk of graft rejection and GVHD. This regimen might be an additional option when unrelated donor HSCT is considered for a patient with MPS1-H.

Age- and gender-related differences in teicoplanin levels in paediatric patients.

OBJECTIVES: Teicoplanin is a glycopeptide antibiotic active against Gram-positive bacteria, including methicillin-resistant staphylococci. While teicoplanin trough levels (TTLs) >10 mg/L are commonly considered appropriate, levels >20 mg/L are aimed for in the treatment of severe infections. Due to toxicity, it is recommended to avoid levels >60 mg/L. PATIENTS AND METHODS: In our institution, the initial dosing schedule of teicoplanin (10-15 mg/kg every 12 h for three loading doses and every 24 h thereafter) is adapted according to TTLs analysed by a fluorescence polarization immunoassay on treatment days 2 to 4. Teicoplanin peak levels (TPLs) are analysed in selected cases 30 min after the end of infusion. In a retrospective analysis we evaluated 1357 TTLs and 333 TPLs from 410 treatment episodes from 2005 to 2011. RESULTS: Initial TTLs were <10 mg/L in 14.1% and <20 mg/L in 72.6% of episodes. Toddlers had significantly lower TTLs, with a 2-fold and 2.5-fold increased risk of having levels <10 mg/L (24.6%) and <20 mg/L (82.6%), respectively. For the entire cohort, follow-up TTLs were less likely to be <10 mg/L and more likely to be >20 mg/L when compared with initial TTLs (P < 0.001, each). Adolescent girls had significantly higher initial TPLs (P = 0.001) and significantly higher follow-up TTLs (P = 0.016) than adolescent boys. In parallel, adolescent girls had initial TPLs >60 mg/L significantly more frequently (P = 0.012) and follow-up TTLs <10 mg/L significantly less frequently (P = 0.005). CONCLUSIONS: More tailored dosing regimens with higher loading doses, especially for toddlers, should be considered. While further pharmacokinetic data in paediatric patients are pending, therapeutic drug monitoring is mandatory.

Add-on-therapy with bevacizumab in children and adolescents with poor prognosis non-CNS solid tumors.

Bevacizumab is increasingly being used in adult patients with cancer and children with central nervous system (CNS) tumors. Little, however, is known about the efficacy, risks, and benefits of bevacizumab administration in non-CNS tumors of childhood. The aim of the present study was to report on bevacizumab administered as add-on-therapy for poor prognosis non-CNS solid tumors of childhood and adolescence, including a prospective evaluation of side effects of bevacizumab. Seven patients (female: n = 5; median age, 14.5 years) with relapsed (n = 4) or primary metastatic (n = 3) solid non-CNS tumors received bevacizumab at 5-10 mg/kg body weight intravenously every 2-3 weeks. Assessment of cardiac function, thyroid hormone levels, urine analysis, and radiographic responses were carried out every 3 months. The median time of bevacizumab treatment was 10 (range, 5-17) months. Patients received a median of 16 (range, 10-38) bevacizumab infusions. With a median follow-up of 25 (range, 13-38) months, five patients relapsed after 7-25 months and three of them died. Two patients are still in complete remission for 31 and 32 months, respectively. Fraction shortening decreased in two patients. Bevacizumab was associated with new-onset increase in basal thyroid-stimulating hormone (n = 3), mild proteinuria/hematuria (n = 5), intermittent hypertension (n = 2), hypertension requiring antihypertensive medication (n = 3), and epistaxis (n = 2). In two patients, therapy with bevacizumab was terminated because of side effects. Selected patients with relapsed or primary metastatic solid non-CNS tumors of childhood and adolescence might benefit from add-on-therapy with bevacizumab. Although the side effects were usually mild, cardiac monitoring seems to be essential during and after the administration of bevacizumab.

Haploidentical hematopoietic stem cell transplantation as individual treatment option in pediatric patients with very high-risk sarcomas.

Background: Prognosis of children with primary disseminated or metastatic relapsed sarcomas remains dismal despite intensification of conventional therapies including high-dose chemotherapy. Since haploidentical hematopoietic stem cell transplantation (haplo-HSCT) is effective in the treatment of hematological malignancies by mediating a graft versus leukemia effect, we evaluated this approach in pediatric sarcomas as well. Methods: Patients with bone Ewing sarcoma or soft tissue sarcoma who received haplo-HSCT as part of clinical trials using CD3+ or TCRα/ß+ and CD19+ depletion respectively were evaluated regarding feasibility of treatment and survival. Results: We identified 15 patients with primary disseminated disease and 14 with metastatic relapse who were transplanted from a haploidentical donor to improve prognosis. Three-year event-free survival (EFS) was 18,1% and predominantly determined by disease relapse. Survival depended on response to pre-transplant therapy (3y-EFS of patients in complete or very good partial response: 36,4%). However, no patient with metastatic relapse could be rescued. Conclusion: Haplo-HSCT for consolidation after conventional therapy seems to be of interest for some, but not for the majority of patients with high-risk pediatric sarcomas. Evaluation of its future use as basis for subsequent humoral or cellular immunotherapies is necessary.

Anti-GD2 Antibody Dinutuximab Beta and Low-Dose Interleukin 2 After Haploidentical Stem-Cell Transplantation in Patients With Relapsed Neuroblastoma: A Multicenter, Phase I/II Trial.

PURPOSE: Patients with relapsed high-risk neuroblastoma (rHR-NB) have a poor prognosis. We hypothesized that graft-versus-neuroblastoma effects could be elicited by transplantation of haploidentical stem cells (haplo-SCT) exploiting cytotoxic functions of natural killer cells and their activation by the anti-GD2 antibody dinutuximab beta (DB). This phase I/II trial assessed safety, feasibility, and outcomes of immunotherapy with DB plus subcutaneous interleukin-2 (scIL2) after haplo-SCT in patients with rHR-NB. METHODS: Patients age 1-21 years underwent T-/B-cell-depleted haplo-SCT followed by DB and scIL2. The primary end point 'success of treatment' encompassed patients receiving six cycles, being alive 180 days after end of trial treatment without progressive disease, unacceptable toxicity, acute graft-versus-host-disease (GvHD) ≥grade 3, or extensive chronic GvHD. RESULTS: Seventy patients were screened, and 68 were eligible for immunotherapy. Median number of DB cycles was 6 (range, 1-9). Median number of scIL2 cycles was 3 (1-6). The primary end point was met by 37 patients (54.4%). Median observation time was 7.8 years. Five-year event-free survival (EFS) and overall survival from start of trial treatment were 43% (95% CI, 31 to 55) and 53% (95% CI, 41 to 65), respectively. Five-year EFS among patients in complete remission (CR; 52%; 95% CI, 31 to 69) or partial remission (44%; 95% CI, 27 to 60) before immunotherapy were significantly better compared with patients with nonresponse/mixed response/progressive disease (13%; 95% CI, 1 to 42; P = .026). Overall response rate in 43 patients with evidence of disease after haplo-SCT was 51% (22 patients), with 15 achieving CR (35%). Two patients developed GvHD grade 2 and 3 each. No unexpected adverse events occurred. CONCLUSION: DB therapy after haplo-SCT in patients with rHR-NB is feasible, with low risk of inducing GvHD, and results in long-term remissions likely attributable to increased antineuroblastoma activity by donor-derived effector cells.

Modification of the alkaline comet assay with human mesenchymal stem cells.

MSCs (mesenchymal stem cells) are planned foruse in regenerative medicine to offset age-dependent alterations. However, MSCs are affected by replicative senescence associated with decreasing proliferation potential, telomere shortening and DNA damage during in vitro propagation. To monitor in vitro senescence, we have assessed the integrity of DNA by the alkaline comet assay. For optimization of the comet assay we have enhanced the stability of comet slides in liquid and minimized the background noise of the method by improving adhesion of agarose gels on the comet slides and concentrating cells on a defined small area on the slides. The modifications of the slide preparation increase the overall efficiency and reproducibility of the comet assay and minimize the image capture and storage. DNA damage of human MSCs during in vitro cultivation increased with time, as assessed by the comet assay, which therefore offers a fast and easy screening tool in future efforts to minimize replicative senescence of MSCs in vitro.

Alternative donor HSCT in refractory acquired aplastic anemia - prevention of graft rejection and graft versus host disease by immunoablative conditioning and graft manipulation.

Early alternative donor HSCT is a potentially curative therapeutic option for patients with AAA not responding to IST. Seven patients (median age at diagnosis, 11 yr) with refractory AAA without a MSD underwent HSCT from matched unrelated (n = 6) or haploidentical (n = 1) donors. Conditioning regimens included CY (n = 7), muromonab-CD3/ATG (n = 7), TT (n = 6), FLU (n = 5), and TLI (n = 2). Grafts were either CD34 purified and/or CD3/19 depleted and contained a median of 10.17 × 10(6) /kg CD34 and 5.5 × 10(4) /kg CD3 cells. All patients engrafted rapidly. Median time to leukocyte engraftment was 10 days. With a median follow-up of 26 (range, 11-153) months, six patients are alive and well with complete donor hematopoiesis. One heavily pretreated patient developed GVHD grade III and died from progressive renal failure (resulting from microangiopathic hemolytic anemia) and disseminated aspergillosis. Early alternative donor HSCT can help to avoid complications from prolonged IST and presumably improve survival of patients with refractory AAA. Administration of high doses of CD34 purified and/or CD3/19 depleted stem cells following novel immunoablative conditioning may prevent graft rejection and GVHD. However, a long interval from diagnosis to HSCT seems to be associated with poor outcome.