An Anti-Human ICAM-1 Antibody Inhibits Rhinovirus-Induced Exacerbations of Lung Inflammation

Human rhinoviruses (HRV) cause the majority of common colds and acute exacerbations of asthma and chronic obstructive pulmonary disease (COPD). Effective therapies are urgently needed, but no licensed treatments or vaccines currently exist. Of the 100 identified serotypes, ∼90% bind domain 1 of human intercellular adhesion molecule-1 (ICAM-1) as their cellular receptor, making this an attractive target for development of therapies; however, ICAM-1 domain 1 is also required for host defence and regulation of cell trafficking, principally via its major ligand LFA-1. Using a mouse anti-human ICAM-1 antibody (14C11) that specifically binds domain 1 of human ICAM-1, we show that 14C11 administered topically or systemically prevented entry of two major groups of rhinoviruses, HRV16 and HRV14, and reduced cellular inflammation, pro-inflammatory cytokine induction and virus load in vivo. 14C11 also reduced cellular inflammation and Th2 cytokine/chemokine production in a model of major group HRV-induced asthma exacerbation. Interestingly, 14C11 did not prevent cell adhesion via human ICAM-1/LFA-1 interactions in vitro, suggesting the epitope targeted by 14C11 was specific for viral entry. Thus a human ICAM-1 domain-1-specific antibody can prevent major group HRV entry and induction of airway inflammation in vivo.     

Global patterns in seed size

Aim  To provide the first global quantification of the slope and shape of the latitudinal gradient in seed mass, and to determine whether global patterns in seed mass are best explained by growth form, vegetation type, seed dispersal syndrome, or net primary productivity (NPP).
Location  Global.
Methods  We collected seed mass data for 11,481 species × site combinations from around the world. We used regression to describe the latitudinal gradient in seed mass, then applied general linear models to quantify the relative explanatory power of each of the variables hypothesized to underlie the latitudinal gradient in seed size.
Results  There is a 320-fold decline in geometric mean seed mass between the equator and 60°. This decline is not linear. At the edge of the tropics, there is a sudden 7-fold drop in mean seed mass. The strongest correlates of the latitudinal gradient in seed mass are plant growth form, and vegetation type, followed by dispersal syndrome and NPP. A model including growth form, vegetation type, dispersal syndrome and NPP explains 51% of the variation in seed mass. Latitude explains just 0.2% of the residual variation from this model.
Main conclusions  This is the first demonstration of a major decrease in seed size at the edge of the tropics. This drop in seed mass is most closely correlated with changes in plant growth form and vegetation type. This suggests that the drop in seed mass might be part of a sudden change in plant strategy at the edge of the tropics.     

Leaf trait relationships of native and invasive plants: community- and global-scale comparisons

Leaf carbon capture strategies of native and exotic invasive plants were compared by examining leaf traits and their scaling relationships at community and global scales. Community-level leaf trait data were obtained for 55 vascular plant species from nutrient-enriched and undisturbed bushland in Sydney, Australia. Global-scale leaf trait data were compiled from the literature for 75 native and 90 exotic invasive coexisting species. At the community level, specific leaf area (SLA), foliar nitrogen and phosphorus (N(mass) and P(mass)) and N:P ratio were significantly higher for exotics at disturbed sites compared with natives at undisturbed sites, with natives at disturbed sites being intermediate. SLA, N(mass) and P(mass) were positively correlated, with significant shifts in group means along a common standardized major axis (SMA) slope. At the global scale, invasives had significantly higher N(mass), P(mass), assimilation rate (A(mass) and A(area)) and leaf area ratio (LAR) than natives. All traits showed positive correlations, with significant shifts in group means along a common slope. For a given SLA, invasives had higher A(mass) (7.7%) and N(mass) (28%). Thus, exotic invasives do not have fundamentally different carbon capture strategies from natives but are positioned further along the leaf economics spectrum towards faster growth strategies. Species with leaf traits enabling rapid growth will be successful invaders when introduced to novel environments where resources are not limited.