To facilitate subcutaneous dosing, biotherapeutics need to exhibit properties that enable high-concentration formulation and long-term stability in the formulation buffer. For antibody–drug ...conjugates (ADCs), the introduction of drug-linkers can lead to increased hydrophobicity and higher levels of aggregation, which are both detrimental to the properties required for subcutaneous dosing. Herein we show how the physicochemical properties of ADCs could be controlled through the drug-linker chemistry in combination with prodrug chemistry of the payload, and how optimization of these combinations could afford ADCs with significantly improved solution stability. Key to achieving this optimization is the use of an accelerated stress test performed in a minimal formulation buffer.
Glucocorticoids (GCs) are efficacious drugs used for treating many inflammatory diseases, but the dose and duration of administration are limited because of severe side effects. We therefore sought ...to identify an approach to selectively target GCs to inflamed tissue. Previous work identified that anti-tumor necrosis factor (TNF) antibodies that bind to transmembrane TNF undergo internalization; therefore, an anti-TNF antibody-drug conjugate (ADC) would be mechanistically similar, where lysosomal catabolism could release a GC receptor modulator (GRM) payload to dampen immune cell activity. Consequently, we have generated an anti-TNF-GRM ADC with the aim of inhibiting pro-inflammatory cytokine production from stimulated human immune cells. In an acute mouse model of contact hypersensitivity, a murine surrogate anti-TNF-GRM ADC inhibited inflammatory responses with minimal effect on systemic GC biomarkers. In addition, in a mouse model of collagen-induced arthritis, single-dose administration of the ADC, delivered at disease onset, was able to completely inhibit arthritis for greater than 30 days, whereas an anti-TNF monoclonal antibody only partially inhibited disease. ADC treatment at the peak of disease was also able to attenuate the arthritic phenotype. Clinical data for a human anti-TNF-GRM ADC (ABBV-3373) from a single ascending dose phase 1 study in healthy volunteers demonstrated antibody-like pharmacokinetic profiles and a lack of impact on serum cortisol concentrations at predicted therapeutic doses. These data suggest that an anti-TNF-GRM ADC may provide improved efficacy beyond anti-TNF alone in immune mediated diseases while minimizing systemic side effects associated with standard GC treatment.
Numerous amphibian species occupy microhabitats with buffered thermal and moisture conditions, typically under forest canopies. Here, we assessed whether the insular endemic
Salamandra corsica
also ...uses this type of habitat, which could have important implications for its conservation. We used data loggers to record the air temperature and air humidity at 4 h intervals over a period of 2 years, at 13 stations with a confirmed presence of
S. corsica
. These data were compared with those recorded at Corsican weather stations and those generated by a climate model (WorldClim 2). The weather station data showed significant deviations from the probe data, by an average of − 1.26 °C (minimum temperature), + 2.61 °C (maximum temperature), and − 0.04% (relative humidity). Similarly, the WorldClim 2 data showed significant deviations from the probe data, by an average of − 2.49 °C (minimum temperature) and + 1.69 °C (maximum temperature). These discrepancies reflect the use of densely vegetated and topographically complex habitats by
S. corsica
, which reduce temperature fluctuations. Overall, our results highlight the importance of natural vegetal cover in the conservation of populations of this endemic salamander.
Side chains of natural occurring amino acids vary greatly in terms of charge state, polarity, size and hydrophobicity. Using a linear synthetic route, two amino acids were sequentially coupled to a ...potent glucocorticoid receptor modulator (GRM) to afford a library of dipeptide-GRM linker payloads with a range of
in silico
properties. The linker payloads were conjugated to a mouse anti-TNF antibody through interchain disulfide Cys. Impact of various dipeptide linkers on ADC physical properties, including solubility, hydrophobicity, and aggregation were evaluated and the
in silico
properties pI, Log
P
and tPSA of the linker drugs used to correlate with these properties. ADCs were screened in a GRE luciferase reporter assay to compare their
in vitro
efficacy. Data identified Ala-Ala as a superior dipeptide linker that allowed a maximum drug load of 10 while affording ADCs with low aggregation.
A glucocorticoid receptor modulator (GRM) was conjugated to a mouse anti-TNF antibody using various dipeptide linkers. Impact of dipeptide linkers on ADC physical properties, including solubility, hydrophobicity, and aggregation were evaluated.
A new subspecies within the
species complex from north-western Africa is described. Previous molecular analysis showed that the populations of
from north-western Morocco consisted of two well ...supported clades: clade 1 distributed in the Rif Mountains, from Chefchaouen (type locality) to Al Hoceima, and clade 2, located southern from clade 1 being isolated in the northern and central Middle Atlas Mountains. Clade 2 is herein described as a distinct subspecies:
based on morphological data, allopatric range and molecular divergence. This new subspecies shows an uncorrected pairwise distance of 0.0265 from clade 1 based on cytochrome b DNA sequences.
is a slender and large sized salamander with a highly variable colouration pattern. It can be distinguished from
by the greater proportion of coral red in the background colouration, being the only known subspecies of
in which coral red can exceed the proportion of black. Variable number (0-5) of yellow to golden yellow dorsal blotches, but usually in lower numbers than the nominotypical subspecies.
inhabits subhumid to humid forests and karstic systems at mid to high elevations. We briefly discuss the phylogenetic and taxonomic issues among the genus
which encompasses more valid species than currently recognised.
Background
Island species are vulnerable to rapid extinction, so it is important to develop accurate methods to determine their occurrence and habitat preferences. In this study, we assessed two ...methods for modeling the occurrence of the Corsican endemic
Salamandra corsica
, based on macro-ecological and fine habitat descriptors. We expected that models based on habitat descriptors would better estimate
S
.
corsica
occurrence, because its distribution could be influenced by micro-environmental gradients. The occurrence of
S
.
corsica
was modeled according to two ensembles of variables using random forests.
Results
Salamandra corsica
was mainly found in forested habitats, with a complex vertical structure. These habitats are associated with more stable environmental conditions. The model based on fine habitat descriptors was better able to predict occurrence, and gave no false negatives. The model based on macro-ecological variables underestimated the occurrence of the species on its ecological boundary, which is important as such locations may facilitate interpopulation connectivity.
Conclusions
Implementing fine spatial resolution models requires greater investment of resources, but this is advisable for study of microendemic species, where it is important to reduce type II error (false negatives).
We describe a new species of the newt genus
from Umphang Wildlife Sanctuary, Tak Province, western Thailand based on molecular and morphological evidence and named here as
The new species is assigned ...to the subgenus Tylototriton and differs from other species in having dark-brown to blackish-brown body and limbs, truncate snout, prominent antero-medial ends of the expansion of the dentary bones, laterally protruding quadrate regions, indistinct and small rib nodules, a well-segmented vertebral ridge, and rough dorsolateral bony ridges, which are steeper anterior, and curved medially at the posterior ends. The molecular data show that
differs from
sensu stricto by a 5% genetic sequence divergence of the mitochondrial NADH dehydrogenase subunit 2 region gene. The new species and
are both endemic to Thailand, distributed along the Northwest Thai (Dawna) Uplands of Indochina. To clarify the species boundary between
and
, additional field research is needed in adjacent areas.
is restricted to evergreen hill forests in Umphang Wildlife Sanctuary. We suggest that the new species should be classified as Endangered (EN) in the IUCN Red List.
Objective. The nutritional potential of maize´s Puma hybrids was evaluated as silage forage in 50% of the pregnant ewe’s diet. Materials and methods. Sixty-one pregnant ewes were used, assigned to ...the groups: Centli Puma (N = 21), Tsiri Puma (N = 20) and Tlaoli Puma (N = 20) and their weight, body condition (CC), FAMACHA and metabolic profile in gestation were measured, as well as milk production and quality at 15 and 30 days of lactation. In lambs, birth temperature and weight were measured. Results. The weight and CC of the ewes during pregnancy and lactation were not affected by the group (p>0.05). On the other hand, the estimated feed intake was higher in the ewes of the Centli group (p<0.0001), while the FAMACHA values were better in the Centli and Tlaoli groups (p<0.05). Proteins, glucose, cholesterol and β hydroxybutyrate during pregnancy and milk production and composition during lactation were not affected by the group (p>0.05). Neither did the weight of the lambs and their body temperature vary among the three groups (p>0.05). Conclusions. The use of Puma corn hybrid silages developed for grain production has good and similar response in the productive and metabolic parameters of sheep, as well in the lambs.
Objetivo. Se evaluó el potencial alimenticio de híbridos de maíz Puma como forraje ensilado en un 50% de la dieta de ovejas gestantes. Materiales y métodos. 61 ovejas gestantes fueron, asignadas a los grupos: Centli Puma (N = 21), Tsiri Puma (N = 20) y Tlaoli Puma (N = 20), y se les midió el peso, la condición corporal (CC), FAMACHA y perfil metabólico en la gestación, así como la producción y calidad de leche a los 15 y 30 días de lactancia. En los corderos se midió la temperatura al nacimiento y el peso. Resultados. El peso y CC de las ovejas durante la gestación y en la lactancia no fueron afectados por el grupo (p>0.05). Por su parte el consumo estimado de alimento fue mayor en las ovejas del grupo Centli (p<0.0001), mientras que los valores de FAMACHA fueron mejores en los grupos Centli y Tlaoli (p<0.05). Las proteínas, glucosa, colesterol y hidroxibutirato durante la gestación, así como la producción y composición de la leche durante la lactancia no fueron afectos por el grupo (p>0.05). El peso de los corderos y su temperatura no varió entre los tres grupos (p>0.05). Conclusiones. El uso de ensilados de híbridos de maíz Puma desarrollados para producción de grano, tiene buenas y similares respuestas en los parámetros productivos y metabólicos de ovejas, así como en los corderos.
Abstract
Crocodile newts (Echinotriton and Tylototriton) are emblematic of the biodiversity of South-East Asia. In this study, we provide an account of their evolution, diversity and phylogeography ...based on mitochondrial (16.2 kb) and nuclear sequences (3.2 kb), combining barcoding data from nearly 1200 specimens collected over ~180 localities, representative of all lineages known to date. While phylogenies of nuclear data lacked resolution, the mitochondrial tree showed dynamic allopatric speciation that followed climate cooling during the last 10 million years, a pattern shared with many other tropical and subtropical amphibians. In crocodile newts, this implies weak dispersal and local adaptation as contributing factors of isolation, and was accompanied by macro- and micro-evolutionary changes in reproductive behaviours. Specifically, our resolved phylogeny of Tylototriton allowed the tracing of a major shift from conserved habits of terrestrial clutch-spawning towards more plastic strategies involving both aquatic and land spawning of single eggs. Using this framework, we then revised the taxonomy of crocodile newts by describing a new subgenus and two new species. Our study provides a basis to guide future phylogeographic, speciation and conservation research on these iconic amphibians.
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