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BACKGROUND: Children with relapsed central nervous system (CNS tumors), neuroblastoma, sarcomas, and other rare solid tumors face poor outcomes. This prospective clinical trial examined the feasibility of combining genomic and transcriptomic profiling of tumor samples with a molecular tumor board (MTB) approach to make real‑time treatment decisions for children with relapsed/refractory solid tumors. METHODS: Subjects were divided into three strata: stratum 1-relapsed/refractory neuroblastoma; stratum 2-relapsed/refractory CNS tumors; and stratum 3-relapsed/refractory rare solid tumors. Tumor samples were sent for tumor/normal whole-exome (WES) and tumor whole-transcriptome (WTS) sequencing, and the genomic data were used in a multi-institutional MTB to make real‑time treatment decisions. The MTB recommended plan allowed for a combination of up to 4 agents. Feasibility was measured by time to completion of genomic sequencing, MTB review and initiation of treatment. Response was assessed after every two cycles using Response Evaluation Criteria in Solid Tumors (RECIST). Patient clinical benefit was calculated by the sum of the CR, PR, SD, and NED subjects divided by the sum of complete response (CR), partial response (PR), stable disease (SD), no evidence of disease (NED), and progressive disease (PD) subjects. Grade 3 and higher related and unexpected adverse events (AEs) were tabulated for safety evaluation. RESULTS: A total of 186 eligible patients were enrolled with 144 evaluable for safety and 124 evaluable for response. The average number of days from biopsy to initiation of the MTB-recommended combination therapy was 38 days. Patient benefit was exhibited in 65% of all subjects, 67% of neuroblastoma subjects, 73% of CNS tumor subjects, and 60% of rare tumor subjects. There was little associated toxicity above that expected for the MGT drugs used during this trial, suggestive of the safety of utilizing this method of selecting combination targeted therapy. CONCLUSIONS: This trial demonstrated the feasibility, safety, and efficacy of a comprehensive sequencing model to guide personalized therapy for patients with any relapsed/refractory solid malignancy. Personalized therapy was well tolerated, and the clinical benefit rate of 65% in these heavily pretreated populations suggests that this treatment strategy could be an effective option for relapsed and refractory pediatric cancers. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02162732. Prospectively registered on June 11, 2014.

PURPOSE: Long-term survival in high-risk neuroblastoma (HRNB) is approximately 50%, with mortality primarily driven by relapse. Eflornithine (DFMO) to reduce risk of relapse after completion of immunotherapy was investigated previously in a single-arm, phase II study (NMTRC003B; ClinicalTrials.gov identifier: NCT02395666) that suggested improved event-free survival (EFS) and overall survival (OS) compared with historical rates in a phase III trial (Children Oncology Group ANBL0032; ClinicalTrials.gov identifier: NCT00026312). Using patient-level data from ANBL0032 as an external control, we present new analyses to further evaluate DFMO as HRNB postimmunotherapy maintenance. PATIENTS AND METHODS: NMTRC003B (2012-2016) enrolled patients with HRNB (N = 141) after standard up-front or refractory/relapse treatment who received up to 2 years of continuous treatment with oral DFMO (750 ± 250 mg/m2 twice a day). ANBL0032 (2001-2015) enrolled patients with HRNB postconsolidation, 1,328 of whom were assigned to dinutuximab (ch.14.18) treatment. Selection rules identified 92 NMTRC003B patients who participated in (n = 87) or received up-front treatment consistent with (n = 5) ANBL0032 (the DFMO/treated group) and 852 patients from ANBL0032 who could have been eligible for NMTRC003B after immunotherapy, but did not enroll (the NO-DFMO/control group). The median follow-up time for DFMO/treated patients was 6.1 years (IQR, 5.2-7.2) versus 5.0 years (IQR, 3.5-7.0) for NO-DFMO/control patients. Kaplan-Meier and Cox regression compared EFS and OS for overall groups, 3:1 (NO-DFMO:DFMO) propensity score-matched cohorts balanced on 11 baseline demographic and disease characteristics with exact matching on MYCN, and additional sensitivity analyses. RESULTS: DFMO after completion of immunotherapy was associated with improved EFS (hazard ratio [HR], 0.50 [95% CI, 0.29 to 0.84]; P = .008) and OS (HR, 0.38 [95% CI, 0.19 to 0.76]; P = .007). The results were confirmed with propensity score-matched cohorts and sensitivity analyses. CONCLUSION: The externally controlled analyses presented show a relapse risk reduction in patients with HRNB treated with postimmunotherapy DFMO.

Children with relapsed/refractory (R/R) neuroblastoma (NB) and medulloblastoma (MB) have poor outcomes. We evaluated the efficacy of nifurtimox (Nfx) in a clinical trial for children with R/R NB and MB. Subjects were divided into three strata: first relapse NB, multiply R/R NB, and R/R MB. All patients received Nfx (30 mg/kg/day divided TID daily), Topotecan (0.75 mg/m2 /dose, days 1-5) and Cyclophosphamide (250 mg/m2 /dose, days 1-5) every 3 weeks. Response was assessed after every two courses using International Neuroblastoma Response Criteria and Response Evaluation Criteria in Solid Tumors (RECIST) criteria. One hundred and twelve eligible patients were enrolled with 110 evaluable for safety and 76 evaluable for response. In stratum 1, there was a 53.9% response rate (CR + PR), and a 69.3% total benefit rate (CR + PR + SD), with an average time on therapy of 165.2 days. In stratum 2, there was a 16.3% response rate, and a 72.1% total benefit rate, and an average time on study of 158.4 days. In stratum 3, there was a 20% response rate and a 65% total benefit rate, an average time on therapy of 105.0 days. The most common side effects included bone marrow suppression and reversible neurologic complications. The combination of Nfx, topotecan and cyclophosphamide was tolerated, and the objective response rate plus SD of 69.8% in these heavily pretreated populations suggests that this combination is an effective option for patients with R/R NB and MB. Although few objective responses were observed, the high percentage of stabilization of disease and prolonged response rate in patients with multiply relapsed disease shows this combination therapy warrants further testing.

BACKGROUND: Survival for patients with high-risk neuroblastoma (HRNB) remains poor despite aggressive multimodal therapies. AIMS: To study the feasibility and safety of incorporating a genomic-based targeted agent to induction therapy for HRNB as well as the feasibility and safety of adding difluoromethylornithine (DFMO) to anti-GD2 immunotherapy. METHODS: Twenty newly diagnosed HRNB patients were treated on this multicenter pilot trial. Molecular tumor boards selected one of six targeted agents based on tumor-normal whole exome sequencing and tumor RNA-sequencing results. Treatment followed standard upfront HRNB chemotherapy with the addition of the selected targeted agent to cycles 3-6 of induction. Following consolidation, DFMO (750 mg/m2 twice daily) was added to maintenance with dinutuximab and isotretinoin, followed by continuation of DFMO alone for 2 years. DNA methylation analysis was performed retrospectively and compared to RNA expression. RESULTS: Of the 20 subjects enrolled, 19 started targeted therapy during cycle 3 and 1 started during cycle 5. Eighty-five percent of subjects met feasibility criteria (receiving 75% of targeted agent doses). Addition of targeted agents did not result in toxicities requiring dose reduction of chemotherapy or permanent discontinuation of targeted agent. Following standard consolidation, 15 subjects continued onto immunotherapy with DFMO. This combination was well-tolerated and resulted in no unexpected adverse events related to DFMO. CONCLUSION: This study demonstrates the safety and feasibility of adding targeted agents to standard induction therapy and adding DFMO to immunotherapy for HRNB. This treatment regimen has been expanded to a Phase II trial to evaluate efficacy.

Abstract Background Children with relapsed central nervous system (CNS tumors), neuroblastoma, sarcomas, and other rare solid tumors face poor outcomes. This prospective clinical trial examined the feasibility of combining genomic and transcriptomic profiling of tumor samples with a molecular tumor board (MTB) approach to make real‑time treatment decisions for children with relapsed/refractory solid tumors. Methods Subjects were divided into three strata: stratum 1—relapsed/refractory neuroblastoma; stratum 2—relapsed/refractory CNS tumors; and stratum 3—relapsed/refractory rare solid tumors. Tumor samples were sent for tumor/normal whole-exome (WES) and tumor whole-transcriptome (WTS) sequencing, and the genomic data were used in a multi-institutional MTB to make real‑time treatment decisions. The MTB recommended plan allowed for a combination of up to 4 agents. Feasibility was measured by time to completion of genomic sequencing, MTB review and initiation of treatment. Response was assessed after every two cycles using Response Evaluation Criteria in Solid Tumors (RECIST). Patient clinical benefit was calculated by the sum of the CR, PR, SD, and NED subjects divided by the sum of complete response (CR), partial response (PR), stable disease (SD), no evidence of disease (NED), and progressive disease (PD) subjects. Grade 3 and higher related and unexpected adverse events (AEs) were tabulated for safety evaluation. Results A total of 186 eligible patients were enrolled with 144 evaluable for safety and 124 evaluable for response. The average number of days from biopsy to initiation of the MTB-recommended combination therapy was 38 days. Patient benefit was exhibited in 65% of all subjects, 67% of neuroblastoma subjects, 73% of CNS tumor subjects, and 60% of rare tumor subjects. There was little associated toxicity above that expected for the MGT drugs used during this trial, suggestive of the safety of utilizing this method of selecting combination targeted therapy. Conclusions This trial demonstrated the feasibility, safety, and efficacy of a comprehensive sequencing model to guide personalized therapy for patients with any relapsed/refractory solid malignancy. Personalized therapy was well tolerated, and the clinical benefit rate of 65% in these heavily pretreated populations suggests that this treatment strategy could be an effective option for relapsed and refractory pediatric cancers. Trial registration ClinicalTrials.gov, NCT02162732. Prospectively registered on June 11, 2014.

Children with treatment-refractory or relapsed (R/R) tumors face poor prognoses. As the genomic underpinnings driving R/R disease are not well defined, we describe here the genomic and transcriptomic landscapes of R/R solid tumors from 202 patients enrolled in Beat Childhood Cancer Consortium clinical trials. Tumor mutational burden (TMB) was elevated relative to untreated tumors at diagnosis, with one-third of tumors classified as having a pediatric high TMB. Prior chemotherapy exposure influenced the mutational landscape of these R/R tumors, with more than 40% of tumors demonstrating mutational signatures associated with platinum or temozolomide chemotherapy and two tumors showing treatment-associated hypermutation. Immunogenomic profiling found a heterogenous pattern of neoantigen and MHC class I expression and a general absence of immune infiltration. Transcriptional analysis and functional gene set enrichment analysis identified cross-pathology clusters associated with development, immune signaling, and cellular signaling pathways. While the landscapes of these R/R tumors reflected those of their corresponding untreated tumors at diagnosis, important exceptions were observed, suggestive of tumor evolution, treatment resistance mechanisms, and mutagenic etiologies of treatment. SIGNIFICANCE: Tumor heterogeneity, chemotherapy exposure, and tumor evolution contribute to the molecular profiles and increased mutational burden that occur in treatment-refractory and relapsed childhood solid tumors.

Neuroblastoma is a sympathetic nervous system tumor, primarily presenting in children under 6 years of age. The long-term prognosis for patients with high-risk neuroblastoma (HRNB) remains poor despite aggressive multimodal therapy. This report provides an update to a phase II trial evaluating DFMO as maintenance therapy in HRNB. Event-free survival (EFS) and overall survival (OS) of 81 subjects with HRNB treated with standard COG induction, consolidation and immunotherapy followed by 2 years of DFMO on the NMTRC003/003b Phase II trial were compared to a historical cohort of 76 HRNB patients treated at Beat Childhood Cancer Research Consortium (BCC) hospitals who were disease-free after completion of standard upfront therapy and did not receive DFMO. The 2- and 5-year EFS were 86.4% [95% confidence interval (CI) 79.3%-94.2%] and 85.2% [77.8%-93.3%] for the NMTRC003/003b subset vs 78.3% [69.5%-88.3%] and 65.6% [55.5%-77.5%] for the historical control group. The 2- and 5-year OS were 98.8% [96.4-100%] and 95.1% [90.5%-99.9%] vs 94.4% [89.3%-99.9%] and 81.6% [73.0%-91.2%], respectively. DFMO maintenance for HRNB after completion of standard of care therapy was associated with improved EFS and OS relative to historical controls treated at the same institutions. These results support additional investigations into the potential role of DFMO in preventing relapse in HRNB.

High risk neuroblastoma (HRNB) accounts for 15% of all pediatric cancer deaths. Despite aggressive therapy approximately half of patients will relapse, typically with only transient responses to second-line therapy. This study evaluated the ornithine decarboxylase inhibitor difluoromethylornithine (DFMO) as maintenance therapy to prevent relapse following completion of standard therapy (Stratum 1) or after salvage therapy for relapsed/refractory disease (Stratum 2). This Phase II single agent, single arm multicenter study enrolled from June 2012 to February 2016. Subjects received 2 years of oral DFMO (750 ± 250 mg/m2 twice daily). Event free survival (EFS) and overall survival (OS) were determined on an intention-to-treat (ITT) basis. 101 subjects enrolled on Stratum 1 and 100 were eligible for ITT analysis; two-year EFS was 84% (±4%) and OS 97% (±2%). 39 subjects enrolled on Stratum 2, with a two-year EFS of 54% (±8%) and OS 84% (±6%). DFMO was well tolerated. The median survival time is not yet defined for either stratum. DFMO maintenance therapy for HRNB in remission is safe and associated with high EFS and OS. Targeting ODC represents a novel therapeutic mechanism that may provide a new strategy for preventing relapse in children with HRNB.

Abstract Background Survival for patients with high‐risk neuroblastoma (HRNB) remains poor despite aggressive multimodal therapies. Aims To study the feasibility and safety of incorporating a genomic‐based targeted agent to induction therapy for HRNB as well as the feasibility and safety of adding difluoromethylornithine (DFMO) to anti‐GD2 immunotherapy. Methods Twenty newly diagnosed HRNB patients were treated on this multicenter pilot trial. Molecular tumor boards selected one of six targeted agents based on tumor‐normal whole exome sequencing and tumor RNA‐sequencing results. Treatment followed standard upfront HRNB chemotherapy with the addition of the selected targeted agent to cycles 3–6 of induction. Following consolidation, DFMO (750 mg/m2 twice daily) was added to maintenance with dinutuximab and isotretinoin, followed by continuation of DFMO alone for 2 years. DNA methylation analysis was performed retrospectively and compared to RNA expression. Results Of the 20 subjects enrolled, 19 started targeted therapy during cycle 3 and 1 started during cycle 5. Eighty‐five percent of subjects met feasibility criteria (receiving 75% of targeted agent doses). Addition of targeted agents did not result in toxicities requiring dose reduction of chemotherapy or permanent discontinuation of targeted agent. Following standard consolidation, 15 subjects continued onto immunotherapy with DFMO. This combination was well‐tolerated and resulted in no unexpected adverse events related to DFMO. Conclusion This study demonstrates the safety and feasibility of adding targeted agents to standard induction therapy and adding DFMO to immunotherapy for HRNB. This treatment regimen has been expanded to a Phase II trial to evaluate efficacy.

The subject of the present text is the complicated and ambiguous relationship between literature and history in the 20th century. The author has chosen to illustrate the complexity of this relationship by a short reflexion on three remarkable literary works that reflect, each in its own way, the historical dramas of the last century: The Thibaults by Roger Martin du Gard, A Fable by William Faulkner, and The Roots of Heaven by Romain Gary

Background/Aims: The small molecule, Tolfenamic acid (TA) has shown anti-cancer activity in pre-clinical models and is currently in Phase I clinical trials at MD Anderson Cancer Center Orlando. Since specificity and toxicity are major concerns for investigational agents, we tested the effect of TA on specific targets, and assessed the cellular and organismal toxicity representing pre-clinical studies in cancer. Methods: Panc1, L3.6pl, and MiaPaCa-2 (pancreatic cancer), hTERT-HPNE(normal), and differentiated/un-differentiated SH-SY5Y (neuroblastoma) cells were treated with increasing concentrations of TA. Cell viability and effect on specific molecular targets, Sp1 and survivin were determined. Athymic nude mice were treated with vehicle or TA (50mg/kg, 3times/week for 6 weeks) and alterations in the growth pattern, hematocrit, and histopathology of gut, liver, and stomach were monitored. Results: TA treatment decreased cell proliferation and inhibited the expression of Sp1 and survivin in cancer cells while only subtle response was observed in normal (hTERT-HPNE) and differentiated SH-SY5Y cells. Mice studies revealed no effect on body weight and hematocrit. Furthermore, TA regimen did not cause signs of internal-bleeding or damage to vital tissues in mice. Conclusion: These results demonstrate that TA selectively inhibits malignant cell growth acting on specific targets and its chronic treatment did not cause apparent toxicity in nude mice.

Neuroblastoma (NB) is the most common cancer in infancy and most frequent cause of death from extracranial solid tumors in children. Ornithine decarboxylase (ODC) expression is an independent indicator of poor prognosis in NB patients. This study investigated safety, response, pharmacokinetics, genetic and metabolic factors associated with ODC in a clinical trial of the ODC inhibitor difluoromethylornithine (DFMO) ± etoposide for patients with relapsed or refractory NB.Twenty-one patients participated in a phase I study of daily oral DFMO alone for three weeks, followed by additional three-week cycles of DFMO plus daily oral etoposide. No dose limiting toxicities (DLTs) were identified in patients taking doses of DFMO between 500-1500 mg/m2 orally twice a day. DFMO pharmacokinetics, single nucleotide polymorphisms (SNPs) in the ODC gene and urinary levels of substrates for the tissue polyamine exporter were measured. Urinary polyamine levels varied among patients at baseline. Patients with the minor T-allele at rs2302616 of the ODC gene had higher baseline levels (p=0.02) of, and larger decreases in, total urinary polyamines during the first cycle of DFMO therapy (p=0.003) and had median progression free survival (PFS) that was over three times longer, compared to patients with the major G allele at this locus although this last result was not statistically significant (p=0.07). Six of 18 evaluable patients were progression free during the trial period with three patients continuing progression free at 663, 1559 and 1573 days after initiating treatment. Median progression-free survival was less among patients having increased urinary polyamines, especially diacetylspermine, although this result was not statistically significant (p=0.056).DFMO doses of 500-1500 mg/m2/day are safe and well tolerated in children with relapsed NB. Children with the minor T allele at rs2302616 of the ODC gene with relapsed or refractory NB had higher levels of urinary polyamine markers and responded better to therapy containing DFMO, compared to those with the major G allele at this locus. These findings suggest that this patient subset may display dependence on polyamines and be uniquely susceptible to therapies targeting this pathway.Clinicaltrials.gov NCT#01059071.

The Asiatic fruit fly Drosophila suzukii has recently invaded Europe and North and South America, causing severe damage to fruit production systems. Although agronomic host plants of that fly are now well documented, little is known about the suitability of wild and ornamental hosts in its exotic area. In order to study the potential trophic niche of D. suzukii with relation to fruit characteristics, fleshy fruits from 67 plant species were sampled in natural and anthropic ecosystems (forests, hedgerows, grasslands, coastal areas, gardens and urban areas) of the north of France and submitted to experimental infestations. A set of fruit traits (structure, colour, shape, skin texture, diameter and weight, phenology) potentially interacting with oviposition choices and development success of D. suzukii was measured. Almost half of the tested plant species belonging to 17 plant families allowed the full development of D. suzukii. This suggests that the extreme polyphagy of the fly and the very large reservoir of hosts producing fruits all year round ensure temporal continuity in resource availability and contribute to the persistence and the exceptional invasion success of D. suzukii in natural habitats and neighbouring cultivated systems. Nevertheless, this very plastic trophic niche is not systematically beneficial to the fly. Some of the tested plants attractive to D. suzukii gravid females stimulate oviposition but do not allow full larval development. Planted near sensitive crops, these "trap plants" may attract and lure D. suzukii, therefore contributing to the control of the invasive fly.

Unable to form cellular capsules around large foreign bodies, the species Drosophila subobscura Collin in Gordon, 1936 was previously shown devoid of lamellocytes, the capsule-forming hemocytes in Drosophila melanogaster Meigen, 1830. This unusual case of deficiency in encapsulation ability was remarkable enough to motivate further investigations in phylogenetically related species of the obscura group. Like D. subobscura, the species Drosophila azteca Sturtevant and Dobzhansky, 1936, Drosophila bifasciata Pomini, 1940, Drosophila guanche Monclus, 1976, Drosophila miranda Dobzhansky, 1935, Drosophila persimilis Dobzhansky and Epling, 1944, and Drosophila pseudoobcura Frovola and Astaurov, 1929 were found to be unable to encapsulate large foreign bodies and also to lack lamellocytes. Surprisingly, Drosophila affinis Sturtevant, 1916, Drosophila tolteca Patterson and Mainland, 1944, and Drosophila obscura Fallen, 1823 were capable of mounting cellular capsules, although their encapsulation abilities remained weak. These three species were free of lamellocytes but possessed small pools of never before described 'atypical hemocytes' present in the hemolymph when capsules were formed. Incapable de former des capsules autour de corps etrangers de grande taille, l'espece Drosophila subobscura Collin in Gordon, 1936 a ete precedemment decrite comme depourvue de lamellocytes, les hemocytes responsables de la formation de capsules chez Drosophila melanogaster Meigen, 1830. Ce cas insolite de deficience de la capacite d'encapsulement est suffisamment remarquable pour motiver une etude plus approfondie des especes phylogenetiquement proches appartenant au groupe obscura. Comme D. subobscura, les especes Drosophila azteca Sturtevant et Dobzhansky, 1936, Drosophila bifasciata Pomini, 1940, Drosophila guanche Monclus, 1976, Drosophila miranda Dobzhansky, 1935, Drosophila persimilis Dobzhansky et Epling, 1944 et Drosophila pseudoobcura Frovola et Astaurov, 1929 se sont averees incapables d'encapsuler des corps etrangers volumineux et sont egalement demunies de lamellocytes. En revanche, de maniere surprenante, Drosophila affinis Sturtevant, 1916, Drosophila tolteca Patterson et Mainland, 1944 et Drosophila obscura Fallen, 1823 se sont revelees aptes a former des capsules, bien que de facon limitee. Ces trois especes sont depourvues de lamellocytes, mais possedent d'autres formes inedites d'hemocytes dits << atypiques >> dont la presence dans l'hemolymphe est systematiquement associee a la formation de capsules., Introduction A large part of our knowledge on insect immunity comes from the study of the model species, Drosophila melanogaster Meigen, 1830. For instance, it is well established that large [...]

Abstract: Ichneumonoidae parasitoids have been well described for their regulatory effects on host physiology which are usually associated with the activity of polydnaviruses (PDVs) or viruslike-particles (VLPs) injected by the female wasps at oviposition. Among them, parasitoids of the braconid families display specific characteristics like the required activity of secretions from the maternal venom glands or of teratocytes from embryological origin. However, none of these features were observed in two braconid species of the Asobara genus parasitizing Drosophila hosts. In the absence of PDVs and VLPs, the two species A. tabida and A. citri seem to have developed unique strategies to avoid immunity defenses and to succeed in their Drosophila larval hosts. The aim of this study is to report on the complex relationships of braconid parasitoids with their hosts and to present some of the insights from studying Drosophila parasitoids. [Copyright &y& Elsevier]

Abstract: The hymenopteran wasp Leptopilina boulardi (Figitidae) is a larval solitary parasitoid of Drosophila larvae of the melanogaster sub-group. The factors used by parasitoid females to prevent encapsulation of their eggs by the host are localized in the female long gland and reservoir. We report here the physiological effects of these factors on host haemocytes using in vivo injection experiments. The total number of haemocytes, the number of plasmatocytes and the number of crystal cells were not modified by injection of long gland extracts. In contrast, long gland extracts either from virulent or avirulent strains had a significant effect on the lamellocyte number. Compared to the Ringer control, the avirulent long gland products induced an increase of the lamellocyte number while virulent extracts induced a drastic decrease together with an alteration of the morphology of these cells. Interestingly, changes in the lamellocyte morphology were also observed following injection of the P4 protein, a major component of L. boulardi female long glands that displays a strong immune suppressive effect on Drosophila larvae. The implication of the P4 protein in suppressing the host cellular immunity is discussed in correlation with its predicted molecular function as a Rho-GAP protein. [Copyright &y& Elsevier]

Toxoplasma gondii is a parasite that causes severe health problems in the world. Toxoplasmosis, an infection caused by T. gondii , leads to high risk of mortality in patients with immunodeficiency, transplantation, and cancer. Besides that, it causes miscarriages in pregnancy, various abnormalities such as hydrocephalus in infants and congenital diseases. Because the clinical indication of the disease is not specific, it is confused with many diseases, and this leads to the necessity of directly detecting the presence of the toxoplasmosis. Therefore, various diagnostic assays are needed for the diagnosis of the disease. Amongs them, latex agglutination assay is widely used for the detection of specific antibodies or antigens in samples. Latex particles are coated with immunogenic molecules (antigens) to detect antibodies in the blood or used to identify antigens when coated with specific antibodies. In both, aggregation of latex particles results in agglutination. Monoclonal antibodies are often used in latex agglutination assay as in other diagnostic methods. However, monoclonal antibodies can be produced in low quantities at a high cost. Besides, to produce monoclonal antibodies, an experienced staff, a well-equipped cell culture laboratory, a long period of time, and a burdened budget are needed. In recent years, as an alternative to monoclonal antibodies, immunoglobulin Y (IgY) antibodies, which are obtained from chicken eggs, and specifically produced against desired antigenic constructs, have become quite attractive in terms of both low cost and abundant production without requiring infrastructure. In contrast, the latex assay based on IgY antibodies for use in the diagnosis of T. gondii has not been developed. This study aimed to conjugate T. gondii -specific IgY antibodies to latex particles, characterize the particles by Fourier transform infrared spectroscopy, scanning electron microscopy, and spectroscopic methods, and finally demonstrate the interaction with T.gondii parasites in culture with scanning electron microscopy analysis. • Toxoplasma gondii is a parasite that causes serious health problems in the world. • Because the clinical indication is not specific, detecting of parasite is important. • Latex agglutination assay is used for the detection of antibodies or antigens in sample. • IgY antibodies are quite attractive in terms of low cost and high production amount. [ABSTRACT FROM AUTHOR]

Animal medication is a behavioral strategy to resist enemies based on the use of substances from the environment. While it has been observed in several animals, whether invasive species can use medication to resist new enemies during its expansion is unknown. Here, we show that the worldwide invasive pest Drosophila suzukii performs trans-generational prophylactic medication by adapting its oviposition behavior in the presence of enemies. We find that flies preferentially lay their eggs on media containing atropine - an entomotoxic alkaloid - in the presence of parasitoids. We further show that flies developing on atropine more efficiently resist parasitization by parasitoids. Finally, we find that developing in hosts reared on atropine strongly impacts the life-history traits of parasitoids. This protective behavior is reported for the first time in a pest and invasive species, and suggests that animal medication may be an important driver of population dynamics during invasions. [ABSTRACT FROM AUTHOR]

Abstract: Asobara japonica (Braconidae) is an endophagous parasitoid developing in Drosophila larvae. The present study shows that A. japonica was never encapsulated in Drosophila melanogaster, and that it caused an overall inhibition of the host encapsulation reaction since injected foreign bodies were never encapsulated in parasitized hosts. Both the number of circulating hemocytes and the phenoloxidase activity decreased in parasitized larvae, and the hematopoietic organ appeared highly disrupted. We also found that A. japonica venom secretions had atypical effects on hosts compared to other braconid wasps. A. japonica venom secretions induced permanent paralysis followed by death of D. melanogaster larvae, whether injected by the female wasp during an interrupted oviposition, or manually injected into unparasitized larvae. More remarkably, these effects could be reversed by injection of ovarian extracts from female wasps. This is the first report that the venom of an endophagous braconid parasitoid can have a deadly effect on hosts, and moreover, that ovarian extracts can act as an antidote to reverse the effects of the wasp''s venom. These results also demonstrate that A. japonica secretions from both venom gland and ovary are required to regulate synergistically the host physiology for the success of the parasitoid. [Copyright &y& Elsevier]

Co-evolution of host-parasitoid interactions is determined by the costs of host resistance, which received empirical evidence, and the costs of parasitoid virulence, which have been mostly hypothesized. Asobara tabida is a parasitoid, which mainly parasitizes Drosophila melanogaster and D. subobscura, the first species being able to resist to the parasitoid development while the second species is not. To parasitize resistant hosts, including D. melanogaster, A. tabida develops sticky eggs, which prevent encapsulation, but this virulence mechanism may be costly. Interindividual and interpopulation variation in the proportion of sticky eggs respectively allowed us to (i) artificially select and compare life-history traits of a virulent and a nonvirulent laboratory strain, and (ii) compare a virulent and a nonvirulent field strain, to investigate the hypothetical costs of virulence. We observed strong differences between the 2 laboratory strains. The nonvirulent strain invested fewer resources in reproduction and walked less than the virulent one but lived longer. Concerning the field strains, we observed that the nonvirulent strain had larger wings while the virulent one walked more and faster. All together, our results suggest that virulence may not always be costly, but rather that different life histories associated with different levels of virulence may coexist at both intra- and interpopulation levels., (© 2016 Institute of Zoology, Chinese Academy of Sciences.)

The Asiatic fruit fly Drosophila suzukii has recently invaded Europe and North and South America, causing severe damage to fruit production systems. Although agronomic host plants of that fly are now well documented, little is known about the suitability of wild and ornamental hosts in its exotic area. In order to study the potential trophic niche of D. suzukii with relation to fruit characteristics, fleshy fruits from 67 plant species were sampled in natural and anthropic ecosystems (forests, hedgerows, grasslands, coastal areas, gardens and urban areas) of the north of France and submitted to experimental infestations. A set of fruit traits (structure, colour, shape, skin texture, diameter and weight, phenology) potentially interacting with oviposition choices and development success of D. suzukii was measured. Almost half of the tested plant species belonging to 17 plant families allowed the full development of D. suzukii. This suggests that the extreme polyphagy of the fly and the very large reservoir of hosts producing fruits all year round ensure temporal continuity in resource availability and contribute to the persistence and the exceptional invasion success of D. suzukii in natural habitats and neighbouring cultivated systems. Nevertheless, this very plastic trophic niche is not systematically beneficial to the fly. Some of the tested plants attractive to D. suzukii gravid females stimulate oviposition but do not allow full larval development. Planted near sensitive crops, these "trap plants" may attract and lure D. suzukii, therefore contributing to the control of the invasive fly.

We recently reported that most of the Drosophila species of the obscura group were unable to mount cellular capsules and no lamellocyte was ever found in the hemolymph of any of the tested species. Only three species were able to encapsulate, despite lacking lamellocytes. Their encapsulation ability was always associated with the presence of an unpreviously described kind of capsule-forming immunocytes designated as "atypical hemocytes". Here, we describe the ultrastructural and functional characteristics of this type of hemocyte. We show that these cells share many ultrastructural and morphological features with Drosophila melanogaster plasmatocytes, although they are involved in the formation of the external layers of the cellular capsule, a functional property exhibited by lamellocytes in D. melanogaster. Due to the high number of pseudopodes in these cells, we suggest to name them "pseudopodocytes". After structural and functional characterization of these atypical hemocytes, their ambiguous status between plasmatocytes and lamellocytes is discussed., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

The immunity of Drosophila relies on a variety of defenses cooperating to fight parasites and pathogens. The encapsulation reaction is the main hemocytic response neutralizing large parasites like endophagous parasitoids. The diversity of the mechanisms of immunoevasion evolved by Asobara parasitoids, together with the wide spectrum of Drosophila host species they can parasitize, make them ideal models to study and unravel the physiological and cellular aspects of host immunity. This chapter summarizes what could be learnt on the cellular features of the encapsulation process in various Drosophila spp., and also on the major role played by Drosophila hosts hemocytes subpopulations, both in a quantitative and qualitative manner, regarding the issue of the immune Asobara-Drosophila interactions.

Eggs and larvae of endophagous parasitoids face the host's immunity reaction once they penetrate the insect host's hemocele. In order to overcome the host's immune barrier, endoparasitoids have developed various strategies. Conformer parasitoids hide and/or get protected from the attack by the host's immunity cells without interfering with the host's immune system. Differently, regulator parasitoids directly attack the host's hemocytes, therefore totally inhibiting the immunity reaction of encapsulation in the parasitized host. Female wasps may also discriminate immunoreactive hosts from nonreactive, permissive ones before laying an egg. These different strategies coexist within the same genus of the braconids Asobara, endoparasitoids of Drosophila larvae. The physiological mechanisms underlying the conformer and regulator strategies in Asobara are exposed. The factors which may contribute to the diversity of the means developed by Asobara parasitoids to overcome the hosts' immunity defenses are discussed.

The Drosophila subobscura larvae were found to be unable to form a capsule around a parasitic egg or an inert foreign body. The specificity and physiological causes of this incapacity were also explored: analysis of the circulating hemocytes showed that no lamellocyte was ever found in D. subobscura host larvae. Therefore, the fly D. subobscura is the first discovered animal species to present an innate immunodeficiency against a wide range of parasites. This is contrary to the theories that propose that all organisms, in natural conditions, are potentially able to defend themselves against parasitization. This unexpected finding opens evolutionary debates about the cost of immune resistance not only at the level of a population, but also of a whole species. We believe this species of fruitfly could become a new model system to study genes involved in hematopoïesis, and in a larger context to better understand defence reactions in organisms.

The endoparasitoid Asobara citri avoids Drosophila melanogaster immune defenses, thanks to immune suppressive effects. We investigated whether this parasitoid could also circumvent the immune reaction of D. simulans, a sibling species of D. melanogaster. The rates of infestation, successful parasitism, total encapsulation and mortality were measured after complete development of both D. melanogaster and D. simulans larvae parasitized by A. citri. Results showed that the parasitoids were almost never encapsulated in D. melanogaster larvae, while 45% were encapsulated in D. simulans. A. citri induced a targeted disruption of the hematopoietic organs and a decrease of the hemocytes load in host larvae of both species. Despite such disruptive immune effects most D. simulans larvae succeeded in encapsulating A. citri eggs, probably thanks to their ability to immediately mount a capsule after infestation. This work brings some insight into the diversity of the immune potentials evolved by Drosophila species towards parasitoids.

We explore two possible hypotheses about the ecological factors driving the evolution of hemocyte load in insects. The first is parasite infection risk, its variability and the genetic diversity of parasites. The other supposes that all the other factors of environmental stress drive the evolution through a pleiotropic selection on metabolic rate. The two hypotheses are tested with data on hemocyte load and ecology of six Drosophila species of the melanogaster subgroup. Hemocyte load correlates significantly with the parasite-driven selection index, but not with the stress selection index. The result being based on too little data to conclude definitely, this work must be considered more as a methodological research based on published results on insect physiology immunity and ecology rather than an empirical evidence of such a relationship.

Asobara tabida and Asobara citri are two braconid endoparasitoids of Drosophila melanogaster larvae. We studied and compared the strategies evolved by these two species to avoid the immune reaction of their host. A. tabida has no negative impact on host cellular defenses and its eggs avoid encapsulation by adhering to host tissues. At the opposite, we found that A. citri, whose eggs are devoid of adhesive properties, affects the host encapsulation abilities, hemolymph phenoloxidase activity and concentrations of circulating hemocytes. Some of these effects could directly rely on a severe disruption of the hematopoietic organ anterior lobes observed in parasitized larvae. This is the first report of the immune suppressive abilities of a parasitoid from the Asobara genus. Results are presented and discussed with respect to the strategies of virulence evolved by other parasitoids to counteract the D. melanogaster immune system.

The hymenopteran Asobara tabida Nees (Braconidae, Alysiinae) develops as a solitary endophagous parasite in larvae of several Drosophila species. Most A. tabida eggs possess a sticky chorion which attaches to the tissue of the host organs within a few hours following oviposition. A. tabida sticky eggs usually avoid encapsulation, though the probability of survival decreases in hosts carrying a larger number of circulating hemocytes. Here, we hypothesized that the elicitation of the encapsulation reaction may result from a race between two phenomena: the host's hemocytic reaction and the embedment of the parasitic egg within the host tissues. In order to test this hypothesis, we measured the speed of capsule formation in D. melanogaster larvae of different ages, knowing that the number of circulating hemocytes increases with the age of the larvae. Using a non-virulent A. tabida strain, the eggs of which do not attach to the host tissue, we found that the speed of capsule formation increased correlatively with the age of the D. melanogaster larva. Therefore, the hypothesis of a physiological race between host's immunity defenses and parasite's avoidance of host's defenses is strongly supported by our results. Also, A. tabida eggs which attach to the host's tissue before the attack by the hemocytes has taken place may be considered as a strategy of passive evasion from encapsulation.

Larvae from six Drosophila species of the melanogaster subgroup were compared for both the hemolymph concentration of hemocytes and the ability to encapsulate the eggs of the parasitoid Asobara tabida (Hymenoptera; Braconidae). Results showed a high correlation between the parasitized hosts' concentration of circulating hemocytes and their aptitude to form a hemocytic capsule around the parasitic eggs. Two conditions seem to be required for the encapsulation of A. tabida eggs to succeed: one condition, which may relate to the recognition of the parasite by the host defense system, is the occurrence of a primary hemocytic response, which gives rise to the amplification of the hemocyte population; the other condition is the presence in the parasitized hosts of a hemocyte load large enough for the cellular capsule to be completed before the parasitic egg becomes protected by embedment within the host tissues. Since the concentration in hemocytes of the parasitized hosts is partially related to the concentration in hemocytes before parasitization, Drosophila species carrying a high hemocyte load could be better predisposed to resist A. tabida. Results are discussed in regard to the importance of a non-specific, quantitative character, such as the host hemocyte load, for the co-evolutionary immune interactions between A. tabida and its Drosophila hosts.