2 research outputs found
Interspecific differences in the oleoresin production of Copaifera L. (Fabaceae) in the Amazon rainforest
Context
Copaifera species produce an oleoresin of commercial importance that is widely extracted in Amazon communities.
Aims
This paper addresses two questions. (1) What are the morphological characteristics of Copaifera species that influence oleoresin production? (2) How do different Copaifera species respond to repeated harvests?
Methods
We performed a large-scale experiment in the Brazilian Amazon. We tapped 110 Copaifera trees belonging to four species, and several morphological tree characteristics were measured to determine their effect on oleoresin production.
Results
The proportion of Copaifera reticulata and Copaifera paupera trees that yielded more than 1 ml oleoresin was higher than the other species. The oleoresin volumes from yielding Copaifera pubiflora trees were significantly higher than those from C. reticulata and C. paupera, with Copaifera multijuga yielding intermediate values. Interestingly, none of the studied morphological tree characteristics had a significant effect on the proportion of yielding trees. Hollowed trees yielded significantly smaller volumes than non-hollowed trees. Both the proportion of yielding trees and oleoresin volumes decreased from the first to the second harvests for
C. reticulata and C. paupera; however, the opposite pattern
was observed for C. pubiflora.
Conclusions
Oleoresin production capacity varies by species, and management protocols should account for these differences
CD137 (4-1BB) costimulation of CD8+ T cells is more potent when provided in cis than in trans with respect to CD3-TCR stimulation
CD137 (4-1BB; TNFSR9) is an activation-induced surface receptor that through costimulation effects provide antigen-primed T cells with augmented survival, proliferation and effector functions as well as metabolic advantages. These immunobiological mechanisms are being utilised for cancer immunotherapy with agonist CD137-binding and crosslinking-inducing agents that elicit CD137 intracellular signaling. In this study, side-by-side comparisons show that provision of CD137 costimulation in-cis with regard to the TCR-CD3-ligating cell is superior to that provided in-trans in terms of T cell activation, proliferation, survival, cytokine secretion and mitochondrial fitness in mouse and human. Cis ligation of CD137 relative to the TCR-CD3 complex results in more intense canonical and non-canonical NF-κB signaling and provides a more robust induction of cell cycle and DNA damage repair gene expression programs. Here we report that the superiority of cis versus trans CD137-costimulation is readily observed in vivo and is relevant for understanding the immunotherapeutic effects of CAR T cells and CD137 agonistic therapies currently undergoing clinical trials, which may provide costimulation either in cis or in trans