Elateridae Research Articles

The complete mitochondrial genome of click beetle Chiagosnius sulcicollis (Coleoptera: Elateridae) and phylogenetic analysis

In this study, we determined the complete mitochondrial genome sequence of click beetle Chiagosnius sulcicollis (Candeze, 1878) (GenBank accession no. MK792747) using next-generation sequencing (NGS) method. The mitogenome is 15,848 bp in length, consisting of 13 protein-coding genes (PCGs), 2 ribosomal RNA genes, 22 transfer RNA genes, and 1 non-coding control region. The overall nucleotide composition was 41.6% A, 31.5% T, 16.6% C, and 10.3% G, with 73.1% AT, respectively. The gene arrangement is consistent with the typical insect mitochondrial genome. Phylogenetic analysis revealed that C. sulcicollis clustered into a clade with Melanotus villosus with high bootstrap support.

The complete mitochondrial genome of click beetle Chiagosnius vittiger (Coleoptera: Elateridae) and phylogenetic analysis

In this study, we determined the complete mitochondrial genome sequence of click beetle Chiagosnius vittiger (Heyden, 1887) (GenBank accession no. MN306531) using next-generation sequencing (NGS) method. The mitogenome is 15,842 bp in length, consisting of 13 protein-coding genes (PCGs), two ribosomal RNA genes (rRNAs), 22 transfer RNA genes (tRNAs), and one non-coding control region. The overall nucleotide composition was 41.6% A, 31.1% T, 16.9% C, and 10.4% G, with 72.7% AT, respectively. The gene arrangement is consistent with the typical insect mitochondrial genome. Phylogenetic analysis revealed that C. vittiger clustered into a clade with Chiagosnius sulcicollis with high bootstrap support.

Hollow peg holds key to click beetles’ explosive flips

Struggling to right themselves when stranded on their backs, click beetles have a remarkable correction strategy. Arching the joint between the front and second section of the thorax, the beetles suddenly release the deformation and spring spontaneously into the air. ‘The jump is almost vertical, but only 50% of cases result in the beetle landing on its feet’, explains mechanical engineer Aimy Wissa, from the University of Illinois Urbana-Champaign, USA, who is fascinated by the tiny insects’ acrobatics. And entomologist Marianne Alleyne, from the University of Illinois Urbana-Champaign, USA, adds, ‘Considering that insects have a small internal volume and, therefore, limited space for large musculature, it is rather amazing how high they can jump without using their legs to push off the ground’. Instead, the beetles depend on a latch structure – situated in the joint between the thorax and the abdomen – which locks the body in position, storing the energy that was released slowly by the muscles that arched the body, ready to be released as soon as the latch lets go. But it was not clear how the two halves of the latch click together, so Wissa, Alleyne and their engineer colleague Alison Dunn teamed up to scrutinise the structure in fine detail.As there are almost 10,000 click beetle species, the team focused on the beetles that reside in their neighbourhoods. ‘We let colleagues, family and friends know that we were in need of living click beetles’, says Alleyne, who recalls how insects were delivered for identification by Alexander Hazel from as far afield as Michigan and Ohio; ‘even the mechanical engineers got involved’, she chuckles. Then, Ophelia Bolmin scrutinised the latch structure of four different click beetles – Alaus oculatus, Parallelostethus attenuatus, Lacon discoideus and Melanotus spp. – in microscopic detail using environmental scanning microscopy. Meanwhile, Lihua Wei CT scanned the head and thorax region of A. oculatus, P. attenuatus and Melanotus spp. to learn about the latch's internal construction.Describing the latch structure, Alleyne explains that a peg on the front section of the thorax slots perfectly onto the lip of the second portion of the thorax, locking the insect's body into an arched position. Also, rows of hairs around the lip cavity guide the peg in to place, and the friction plate toward the tip of the peg locks the latch. Most surprisingly, the CT scans revealed that the peg is hollow. ‘Maybe we shouldn't have been surprised’, says Wissa, explaining that that hollow elongated structures such as pipes and tubes have a higher strength-to-weight ratio than similarly shaped solid structures. And when Dunn calculated the strength of the hollow peg and compared it with the strength of a solid beam, she confirmed that the hollow peg was much stronger, suggesting that a solid peg may be too flexible to hold the latch in place.So click beetles wedge open the latch that allows the insects to store the explosive energy required to fling themselves into the air with a hollow peg. Also, the team suspects that the latch slips when the tension is too high and friction can no longer hold it in place. In addition, they are keen to apply the lessons about power amplification that they have learned from the click beetle to design agile robots that can get out of tight corners.

Soil insects associated with lucumo (Pouteria lucuma L.) trees in La Molina, Lima, Peru

This study aimed to determine the composition and relative abundance of soil insects associated with lucumo (Pouteria lucuma L.) trees growing in the agricultural fields of the Universidad Nacional Agraria La Molina in Lima, Peru. In total, 12 pitfall traps were installed in a 5-ha lucumo field and samples were collected on a weekly basis for approximately 4 months (March–June). Insects in each sample were separated into morphotypes, and the number of individuals in each morphotype and date of collection were recorded. The collected insects were then identified at the Entomology Museum laboratory in Lima through comparison with museum samples and with the help of identification keys. Individuals in the orders Orthoptera (families Acrididae and Gryllidae), Dermaptera (Anisolabididae), Coleoptera (Carabidae, Staphylinidae, Tenebrionidae, Scarabaeidae and Elateridae), Blattodea (Blatellidae) and Hymenoptera (Formicidae) were identified. Among the Coleoptera, Tetracha chilensis (Laporte, 1834) (Carabidae) was the most abundant species; furthermore, Staphylinidae of the subfamily Oxytelinae and the families Elateridae (Conoderus spp.), Tenebrionidae (Epitragopsis sp.) and Scarabaeidae (Ataenius sp.) were identified. Additional taxa identified were as follow: Gryllus assimilis (Fabricius, 1775) (Gryllidae) in Orthoptera, Euborellia annulipes (Lucas, 1847) (Anisolabididae) in Dermaptera and Linepithema spp. in Hymenoptera.

A Wireworm Glyphonix bimarginatus (Schaeffer) (Insecta: Coleoptera: Elateridae)

Glyphonix bimarginatus (Figure 1) is a common click beetle pest of various economically important crops. The larvae of click beetles (Coleoptera: Elateridae) are elongated, wire-like and commonly known as wireworms. Wireworms are considered as subterranean economic pests during their larval stages in many parts of the world including the United States. The larvae of Glyphonix bimarginatus are commonly found with larvae of other click beetles in the field. Larvae of Glyphonix bimarginatus occurs in soil rich in organic matter and rarely in sandy soil. Young roots and germinating seeds are commonly fed upon by the larvae.
 This document describes its distribution, life cycle and biology, hosts, economic importance, and management. Also available on the Featured Creatures website at http://entomology.ifas.ufl.edu/creatures.
 https://edis.ifas.ufl.edu/in1233

Identification of Aggregation-Sex Pheromone Components for a "Living Fossil", the False Click Beetle, Palaeoxenus dohrni Horn (Coleoptera: Eucnemidae).

Insect pheromones have rarely been exploited in surveys or studies of rare and endangered species, despite their potential as effective and highly selective attractants for target species. Here, we report the identification, synthesis, and field bioassays of a male-produced aggregation-sex pheromone blend of a rare false click beetle species endemic to southern California, Dohrn's elegant eucnemid beetle, Palaeoxenus dohrni Horn (Coleoptera: Eucnemidae). This species is the only extant species in its genus and subfamily. Analyses of extracts of headspace volatiles collected from adult beetles revealed several male-specific compounds. Two of these compounds, identified as (E)-2-nonen-4-one and (R)-2-nonanol, elicited electroantennographic responses from antennae of beetles of both sexes. In field bioassays, a blend of the two compounds attracted both sexes, whereas the individual compounds were not attractive. The identification of an attractant pheromone should provide a useful tool for bioconservation and ecological studies of this iconic species.

MONITORING OF HARMFUL ORGANISMS AS THE BASIS OF PHYTOSANITARY OPTIMIZATION OF AGROECOSYSTEMS POTATOES

The studies were conducted in the period from 1988 to 2017 in twelve potato farms of Novosibirsk, Kemerovo regions and Altai. The list of economically significant harmful organisms in potato agroecosystems of forest-steppe of Western Siberia and their classification according to life strategies is given. In potato agroecosystems are dominated by K (Kr) - strategies: multi-year weeds, wireworms (click beetles), Rhizoctonia, Fusarium, Phoma, scab, bacterial, Ditylenchus, viral diseases (72,2 %). Population with r (rK) -strategies: one-year weeds, Colorado potato beetle, late blight and early blight (27,8 %). It is shown, that seed tubers in farms are always infected with sclerotial form of the causative agent of Rhizoctonia, in some cases up to 80 %. The proportion of tubers bacteriosis is about 2 % (up to 20 %), stem nematode in some years reached 19,5 %. Tubers affected by late blight in the region, meet after years epiphitoties the development of the disease reaching 5,8 %. It is shown that the greatest period of survival in the soil is characterized by harmful organisms with K (Kr) life cycle strategy: 5-6 years or more for certain species. Оne-year weed plants are characterized mainly by r (rK) life cycle strategy, have high seed productivity and a wide ecological niche. It was found that the stock of seeds of weed plants in the arable horizon ranges from 8,6 to 22,5 million/ha with a predominance of Amaránthus retrofléxus and Panicum miliaceum. Multi-year weeds mainly with adaptations to (Kr) -strategists form a reserve of powerful underground vegetative mass. Species with r-strategy are more adapted to the development of ground-air environment, forming a significant number of zoospores, conidia, seeds, etc. In the developed system of monitoring and forecast of harmful organisms into account their adaptation to the development of the main factors in adapting to the soil, seed material, development of ground-air environment.

Construction and test of an efficient biophotonic imaging (BPI) reporter system to study pneumococcal biology in vitro and in vivo

Streptococcus pneumoniae is a common nasopharyngeal resident in healthy persons, but remains a major cause of pneumonia, bacteremia and otitis media despite vaccines and effective antibiotics. There is an urgent need for novel therapeutic approaches, but such advances require a detailed knowledge of S. pneumoniae biology and its shift from commensal to pathogen. To better understand pneumococcal biology and infections, we need sensitive in vivo imaging technologies. To this end, bioluminescence imaging can be used, for example, to evaluate anti-infectives, intraspecies interaction and pneumococcal virulence non-invasively. A click beetle luciferase (CBR-luc) containing vector pPP3 under the control of putative highly expressed pneumococcal promoters was constructed. The CBRluc providing red-shifted light production was integrated into known sites in the S. pneumoniae genome. The constructs were compared to a lux-based exist system expressing bacterial luciferase using in vitro growth experiments. The results revealed that CBRluc tagged bacteria, PphrA::luc-wt, showed robust activity of bioluminescence in exponential phase that is maintained during stationary phase, whereas, lux-expressing pneumococci emitted a light signal with high background that peaked during exponential phase and was significantly reduced in intensity during stationary phase. Initial findings demonstrate that the CBRluc reporter system is more efficient than lux, providing a potential platform for utilization in understanding of the mechanisms of pneumococcal pathogenesis in vivo system.

A mid-Cretaceous trichomycete, Priscadvena corymbosa gen. et sp. nov., in Burmese amber

Priscadvena corymbosa gen. et sp. nov., is described from thalli and sporangia emerging from the oral cavity of a click beetle (Coleoptera: Elateridae) in mid-Cretaceous Burmese amber. The fossil contains several features unknown in extant Trichomycetes including a click beetle (Coleoptera: Elateridae) host, spiny, aerial thalli with the entire thallus bearing numerous small uninucleate globular spores and stalks attached to the oral cavity of its host. Based on these features, P. corymbosa gen. et sp. nov. is placed in a new family, Priscadvenaceae fam. nov., and new order, Priscadvenales ord. nov. The new morphological and behavioral features of the fossil add to the diversity of the trichomycetes as currently defined.

Development of Highly Sensitive Biosensors of RAF Dimerization in Cells

The BRAF inhibitors dabrafenib and vemurafenib induce remarkable clinical responses in patients with BRAF-mutated melanomas. However, adverse events, including the emergence of secondary tumors and drug resistance, have been reported. Studies have revealed that undesirable RAF dimerization induced by inhibitors promotes these adverse effects. Here, we developed highly sensitive biosensors of RAF dimerization in cells utilizing the split enhanced click beetle luciferase (Emerald Luc, ELuc) complementation technique. We demonstrated that our biosensor system works effectively for high-throughput screens in the microplate format. A comprehensive analysis of commercially available RAF inhibitors performed using this assay system revealed that the inhibitors exhibit various potencies in inducing the dimerization of RAF isoforms, and their dimerization potencies do not always correlate with the RAF enzyme inhibition. This sensitive assay system will become a powerful tool to discover next-generation BRAF inhibitors with safer profiles.

A first record of complete mitochondrial genome of Cryptalaus Ohira (Insecta: Coleoptera: Elateridae) based on C. yamato (Nakane)

A complete mitochondrial DNA genome of a rare click beetle, Cryptalaus yamato (Nakane), is the first reported. The genome consists of 15,882 base pairs including 13 protein-coding genes (PCGs), 20 tRNAs, two rRNAs, and a 1279 bp long AT-rich region. The overall base composition is 69.4% AT and 30.6% GC. The maximum likelihood analysis based on nucleotide sequence data of 13 PCGs supported that C. yamato is involved in monophyletic group of Elateridae.

The mitochondrial genome of the first luminous click-beetle (Coleoptera: Elateridae) recorded in Asia

The nearly complete mitochondrial genome (mitogenome) of Sinopyrophorus schimmeli Bi et Li, the luminous click beetle recorded in Asia, is described in this study. It totalizes 15,951 bp and contains 13 protein-coding genes (PCGs), two rRNA genes, 22 tRNA genes, and most part of AT-rich region. Thirteen PCGs totalize 11,136 bp, start with ATN, stop with TAA/G, except for cox2 and cox3 stopping with T. The rrnL and rrnS are 1280 and 862 bp, respectively. The AT-rich region contains several structures characteristic of the Coleoptera. The phylogenetic analyses of 13 PCGs confirm the position of S. schimmeli in Elateridae.

Latching of the click beetle (Coleoptera: Elateridae) thoracic hinge enabled by the morphology and mechanics of conformal structures.

Elaterid beetles have evolved to 'click' their bodies in a unique maneuver. When this maneuver is initiated from a stationary position on a solid substrate, it results in a jump not carried out by the traditional means of jointed appendages (i.e. legs). Elaterid beetles belong to a group of organisms that amplify muscle power through morphology to produce extremely fast movements. Elaterids achieve power amplifications through a hinge situated in the thoracic region. The actuating components of the hinge are a peg and mesosternal lip, two conformal parts that latch to keep the body in a brace position until their release, the 'click', that is the fast launch maneuver. Although prior studies have identified this mechanism, they were focused on the ballistics of the launched body or limited to a single species. In this work, we identify specific morphological details of the hinges of four click beetle species - Alaus oculatus, Parallelostethus attenuatus, Lacon discoideus and Melanotus spp. - which vary in overall length from 11.3 to 38.8 mm. Measurements from environmental scanning electron microscopy (ESEM) and computerized tomography (CT) were combined to provide comparative structural information on both exterior and interior features of the peg and mesosternal lip. Specifically, ESEM and CT reveal the morphology of the peg, which is modeled as an Euler-Bernoulli beam. In the model, the externally applied force is estimated using a micromechanical experiment. The equivalent stiffness, defined as the ratio between the applied force and the peg tip deflection, is estimated for all four species. The estimated peg tip deformation indicates that, under the applied forces, the peg is able to maintain the braced position of the hinge. This work comprehensively describes the critical function of the hinge anatomy through an integration of specific anatomical architecture and engineering mechanics for the first time.

Diversity and relationships of Ampedini Gistel, 1848 (Coleoptera : Elateridae) in Switzerland and Europe

The click-beetle family Elateridae is an abundant and ecologically important component of the saproxylic fauna, and many species are used as key indicators of old-growth forests, a rare and endangered habitat in Europe. Among Elateridae, the tribe Ampedini includes several species with unclear taxonomic status. Here we examined the species status and the relationships between 26 of the 29 Ampedini species recorded in Switzerland using both mitochondrial (CO1) and nuclear (ITS2) markers, and compared our results with the CO1 data publicly available for Europe. Our tree-based species-delimitation analysis was largely congruent with traditional, morphology-based species, with the ITS2 and the combined (CO1+ITS2) datasets corresponding more precisely to morphology than the CO1 dataset. As expected, species with unclear or debated taxonomic status generally corresponded to closely related DNA-based species pairs. Our results support the taxonomic status of some of these ambiguous species, while others require further investigations, including a more exhaustive sampling and new morphological examinations. The Ampedini species tree provided here, which is the first attempt of a DNA-based Ampedini phylogeny, did not support the genera Brachygonus and Ampedus as monophyletic, but further investigations are necessary to confirm this result.

Distribution and habitat suitability of two rare saproxylic beetles in Croatia - a piece of puzzle missing for South-Eastern Europe

Abstract: Due to habitat loss and fragmentation, the hermit beetle, Osmoderma eremita species complex (Coleoptera; Scarabidae) and the European red click beetle, Elater ferrugineus Linnaeus, 1758 (Coleoptera: Elateridae) are considered threatened in many European countries. Their presence in a large part of South-Eastern Europe has been sporadically recorded and these findings are mainly historical. Here we present the most recent findings of both species, assembled mainly throughout this first systematic study aiming to collect data on the hermit beetle within mapping and monitoring activities of saproxylic species protected by the European Habitat Directive (Annexes II and IV of Council Directive 92/43/EEC) within the Mediterranean, Continental and Alpine biogeographical regions of Croatia, and current literature data. To facilitate mapping activities and species range monitoring to improve the proper management of suitable habitats, we created habitat suitability maps using recent findings for both species, and predicted distribution were overlapped and analysed with historical data and protected areas. Most of the individuals were captured using flight intercept cross-vein funnel traps baited with pheromone for the hermit beetle placed within natural forest dominated by oak, beech and montane beech-fir forests, on sites with and without any forest management. Among set of 11 environmental variables, autumn precipitation, spring mean temperature and slope contributed most to the beetle distribution models. Data analyses indicated that the European red click beetle has much wider environmental envelope in which it can occur and that the hermit beetle can be used as surrogate species for the European red click beetle.

Assessing the performance of pea and lentil at different seeding densities as trap crops for the management of wireworms in spring wheat

AbstractWireworms, the larvae of click beetles (Elateridae), are difficult to manage due to their habitats and behaviour. Wireworms pose a major threat to the wheat crop in the north‐western USA. Seed treatment with neonicotinoids, biological control management and some cultural controls are recommended to manage these pests. Trap cropping is an emerging way to manage wireworms. In strawberry and potato crops, trap cropping has been found effective at attracting wireworms away from the principal crop. An earlier study in the Golden Triangle area of Montana found that pea and lentil could be effective trap crops for managing wireworms in spring wheat. In the present study, experiments were conducted at two locations. The effectiveness of peas and lentils as trap crops with wheat at different seeding densities was assessed [pea at 0, 4, 8, 16 seeds/sq.ft. or 0, 43, 86, 172 seeds/sq.m.; lentil at 0, 6, 12, 18 OR 0, 65, 130, 194 seeds/sq.m.; both with wheat at 0, 11, 22, or 28 seeds/sq.ft. or 0, 120, 230, 300 seeds/sq.m.] in a randomized design where all three crops were intercropped. Both trap crops were found to be effective in protecting wheat at standard seeding rates of 8 seeds/sq.ft. for pea and 12 seeds/sq.ft. for lentils. At these seeding rates, higher numbers of wireworms were found to be attracted to the trap crop, resulting in higher yield (7%–10%) of the associated spring wheat plant stands at 22 seeds/sq.ft. To develop an effective trap crop strategy, the pea–wheat and lentil–wheat spatial patterns that are possible need to be assessed in further field trials. Proper design and evaluation of the cost–benefit ratio of pea and lentil as trap crops are likely to produce good results for wheat crops in Montana.

Особливості формування видового складу коваликів (Elateridae) у посівах соняшнику і кукурудзи в Лісостепу України

Особливості формування видового складу коваликів (Elateridae) у посівах соняшнику і кукурудзи в Лісостепу України

Modeling Sézary Syndrome for Immunophenotyping and Anti-Tumor Effect of Ucart and Long-Acting Interleukin-7 Combination Therapy

Background: Sézary syndrome (SS) is a highly-morbid T cell leukemic lymphoma with no widely-effective treatments and few preclinical models. We demonstrated effective T cell lymphoma therapy with allogeneic gene-edited anti-CD7 CARTs (Cooper et al, Leukemia, 2018). However, SS T cells typically lose CD7 but maintain ubiquitous high CD2 expression. Thus, we generated CD2- and TRAC-deleted anti-CD2 universal CARTs (UCART2) and multiple SS xenograft models (PDXs) as preclinical UCART2 testing platforms. We further tested a stable homodimeric interleukin-7 molecule, the long-acting form of recombinant human interleukin-7 fused with hybrid Fc (rhIL-7-hyFc, NT-I7), to potentiate UCART2 killing of an SS xenograft in vivo.Methods: To generate SS PDX models, we injected NOD scid IL2Rgammanull (NSG) mice expressing SCF, GM-CSF, and IL-3 (NSG-SGM3) with ~2x106 mononuclear cells derived from SS patients. We immunophenotyped SS patient blood and PDX engraftment with two 21-color flow cytometry panels assessing major immune subsets, CTCL, and exhaustion markers (Staser et al, Cytometry A, 2018). To generate UCART2s, we activated human T cells on CD3/CD28 beads, electroporated the T cells with Cas9, a TRAC-targeted gRNA, and a CD2-targeted gRNA followed by viral transduction with an anti-CD2 scFv 3rd generation CAR. For initial UCART2 testing, we injected NSG mice with 5x105 cells from a human Sézary cell line transduced with click beetle red luciferase (HHCBR-GFP) four days prior to UCART2 treatment. Mice were treated with NT-I7 (10mg/kg SC) on days +1, +15 and +29 post UCART2 infusion.Results: SS patient blood showed specific defects in monocyte, monocytic dendritic cell, and natural killer cell differentiation, increased skewing toward granulocytes and non-classical CD16+ monocytes (p<0.01, SS vs. normal PBMCs), and loss of effector memory CD4 cells (8% vs 34%, p<0.001, SS vs. normal PBMCs). SS cells were CD3+CD4+CD2+CD5+CD8- with variable CD7 loss and PD1 gain. Four of six unique human SS samples injected in NSG-SGM3 mice engrafted within ~6 weeks with no signs of xenogeneic GVHD. Following engraftment, SS cells showed near ubiquitous PD1 expression (>90% vs ~20%, p<0.001, SS vs. normal PBMCs), CD7 loss, and increased CD30 and CD26 expression. Immunohistochemistry further revealed atypical CD3+CD4+CD8-CD7- lymphocytes lining the dermo-epidermal junction. Second generation PDXs showed infiltration of the spleens, blood, and bone marrow with CD2+CD7- human cells and developed alopecia, scaling, and subcutaneous and intraperitoneal masses, with immunophenotyping, sequencing, and UCART treatment studies ongoing.To test UCART2's efficacy in killing SS cells in vivo, we injected NSG mice with HHCBR-GFP+ cells. UCART2-treated HHCBR-GFP mice showed dramatically reduced tumor burden as compared to control UCART19-treated HHCBR-GFP mice (BLI; 10^7 vs. 10^11 photon flux/s at 3 weeks, p<0.0001, UCART2 vs. UCART19). Moreover, UCART2-treated HHCBR-GFP mice survived ~40 days as compared to ~21 days in the UCART19 group. Remarkably, UCART2-treated HHCBR-GFP mice receiving NT-I7 showed virtually no tumor burden (maximum 106 photon flux/s vs. 1010 photon flux/s, UCART2+NT-I7 vs. UCART2 only groups) with 100% of UCART2- and NT-I7-treated HHCBR-GFP mice surviving beyond 49 days (Figure 1).Discussion: We describe the generation of physiologically-relevant SS preclinical models, comprehensive immunophenotyping of patient SS samples, clonal SS PDX outgrowth, and the highly effective anti-tumor activity of UCART2- plus NT-I7-mediated killing of SS cells in vivo using an NSG xenograft model. Ongoing studies involve treating primary SS and CTCL PDX models with UCART2 and NT-I7. These preclinical data validate the use of allogeneic “off-the-shelf” adoptive immunotherapy for the treatment of Sézary syndrome, while demonstrating the dramatic enhancement of CART efficacy using a dose-adjustable, clinic-ready long-acting interleukin-7 agonist given in an adjuvant setting. [Display omitted] DisclosuresPark:NeoImmuneTech: Employment. Lee:NeoImmuneTech: Employment. Musiek:Seattle Genetics: Honoraria; Actelion: Other: Scientific Advisory Committee ; Kyowa Kirin: Honoraria.

AMV564, a Bivalent Bispecific (2×2) CD33/CD3 T-Cell Engager, Is Active and Improves Survival in a Mouse Model of Acute Myeloid Leukemia

Background: AMV564 is a novel bivalent, bispecific (2x2) CD33/CD3 targeted immunotherapy that binds both CD33 and the invariant CD3ε on T-cell receptors with strong avidity, thus creating an immune synapse between CD33-expressing cells and T cells, initiating T-cell directed lysis of CD33 expressing cells, and inducing expansion, differentiation and proliferation of T cells. AMV564 is being evaluated in clinical trials for patients with acute myeloid leukemia (AML, NCT03144245). Previously, we demonstrated that the parent molecule, T564, had specific, T-cell mediated cytotoxic activity against a KG-1 CD33+ cell line in vitro and eliminated blasts in an autologous AML patient-derived xenograft mouse model (Eissenberg, et al. 2015 ASCO). Here we investigated factors that may contribute to antileukemic activity of AMV564 in another, more aggressive, preclinical model of AML.Methods: Disseminated activity studies in NOD scid gamma mice (NSG) were performed by injecting MOLM13 AML cells transduced with click beetle red luciferase and green fluorescent protein (MOLM13-CG) in the tail vein. In a series of experiments, AMV564-mediated clearance of MOLM13-CG cells and overall mouse survival was determined. Tumor cells (either 3.3 x 103 or 1 x 105) were engrafted in non-conditioned NSG mice for 3-7 days. Variables included dose of AMV564 (0.5 to 25 mcg, i.v.), number of AMV564 cycles (1 or 2) and cycle length (4-5 days), number of T cell injections (1 or 2), and total number of human T cells administered (0.2 to 1.2 x 107). Tumor burden was serially measured by bioluminescence (BLI) and survival measured for 51 days.Results: Mouse survival was greatest when AMV564 was injected along with a total number of T cells ≥ 8 x 106 regardless of the number of T cell injections or their timing relative to tumor injection. AMV564 mediated up to a 3-fold increase in survival time compared to untreated mice. In the experiment shown in Figure 1, untreated mice died at day 28, yet about half of the treated mice were still alive when the experiment was terminated on day 51. In the absence of AMV564 (i.e., T cell treatment only), animal survival and tumor burden were similar to that of untreated animals.In the same experiment we administered, AMV564 daily from days 7-11 after MOLM13-CG infusion along with one injection of 8 x 106 human T cells on day 7, then measured tumor burden by BLI signal (Figure 2). By day 14 we observed a median 4.0 log or 4.8 log reduction in tumor using 5 or 25 mcg AMV564. In fact by day 14, 4 of 10 mice treated with 25 mcg AMV564 and 2 of 10 treated with 5 mcg had no detectable signal above background. No rebound in tumor burden occurred in these mice throughout the 51-day study.Conclusions: AMV564 is a potent and effective immunotherapy against an aggressive human AML cell line in NSG mice. AMV564 very effectively prolonged survival and dramatically reduced tumor in the bone marrow and peripheral blood. These results are consistent with our previous preclinical data with primary AML and support the testing of this reagent in patients with relapsed and refractory AML in the clinic. [Display omitted] DisclosuresEissenberg:Amphivena Therapeutics: Research Funding; Novimmune: Research Funding. Rettig:Novimmune: Research Funding; Amphivena Therapeutics: Research Funding. Fox:Sunesis Pharmaceuticals: Employment; Amphivena Therapeutics: Employment. Guenot:Amphivena Therapeutics, Inc: Employment.

Genome sequences identify three families of Coleoptera as morphologically derived click beetles (Elateridae)

Plastoceridae Crowson, 1972, Drilidae Blanchard, 1845 and Omalisidae Lacordaire, 1857 (Elateroidea) are families of the Coleoptera with obscure phylogenetic relationships and modified morphology showing neotenic traits such as soft bodies, reduced wing cases and larviform females. We shotgun sequenced genomes of Plastocerus, Drilus and Omalisus and incorporated them into data matrices of 66 and 4202 single-copy nuclear genes representing Elateroidea. Phylogenetic analyses indicate their terminal positions within the broadly defined well-sclerotized and fully metamorphosed Elateridae and thus Omalisidae should now be considered as Omalisinae stat. nov. in Elateridae Leach, 1815. The results support multiple independent origins of incomplete metamorphosis in Elateridae and indicate the parallel evolution of morphological and ecological traits. Unlike other neotenic elateroids derived from the supposedly pre-adapted aposematically coloured and unpalatable soft-bodied elateroids, such as fireflies (Lampyridae) and net-winged beetles (Lycidae), omalisids and drilids evolved from well-sclerotized click beetles. These findings suggest sudden morphological shifts through incomplete metamorphosis, with important implications for macroevolution, including reduced speciation rate and high extinction risk in unstable habitats. Precise phylogenetic placement is necessary for studies of the molecular mechanisms of ontogenetic shifts leading to profoundly changed morphology.