Identification of an interleukin (IL)-25–dependent cell population that provides IL-4, IL-5, and IL-13 at the onset of helminth expulsion

Type 2 immunity, which involves coordinated regulation of innate and adaptive immune responses, can protect against helminth parasite infection, but may lead to allergy and asthma after inappropriate activation. We demonstrate that il25−/− mice display inefficient Nippostrongylus brasiliensis expulsion and delayed cytokine production by T helper 2 cells. We further establish a key role for interleukin (IL)-25 in regulating a novel population of IL-4–, IL-5–, IL-13–producing non–B/non–T (NBNT), c-kit+, FcɛR1− cells during helminth infection. A deficit in this population in il25−/− mice correlates with inefficient N. brasiliensis expulsion. In contrast, administration of recombinant IL-25 in vivo induces the appearance of NBNT, c-kit+, FcɛR1− cells and leads to rapid worm expulsion that is T and B cell independent, but type 2 cytokine dependent. We demonstrate that these IL-25–regulated cells appear rapidly in the draining lymph nodes, implicating them as a source of type 2 cytokines during initiation of worm expulsion

Effect of surface acoustic waves on the viability, proliferation and differentiation of primary osteoblast-like cells.

Surface acoustic waves (SAWs) have been used as a rapid and efficient technique for driving microparticles into a three-dimensional scaffold matrix, raising the possibility that SAW may be effective in seeding live cells into scaffolds, that is, if the cells were able to survive the infusion process. Primary osteoblast-like cells were used to specifically address this issue: To investigate the effects of SAW on the cells' viability, proliferation, and differentiation. Fluorescence-labeled osteoblast-like cells were seeded into polycaprolactone scaffolds using the SAW method with a static method as a control. The cell distribution in the scaffold was assessed through image analysis. The cells were far more uniformly driven into the scaffold with the SAW method compared to the control, and the seeding process with SAW was also significantly faster: Cells were delivered into the scaffold in seconds compared to the hour-long process of static seeding. Over 80% of the osteoblast-like cells were found to be viable after being treated with SAW at 20 MHz for 10-30 s with an applied power of 380 mW over a wide range of cell suspension volumes (10-100 mul) and cell densities (1000-8000 cellsmul). After determining the optimal cell seeding parameters, we further found that the treated cells offered the same functionality as untreated cells. Taken together, these results show that the SAW method has significant potential as a practical scaffold cell seeding method for tissue and orthopedic engineering

Effect of surface acoustic waves on the viability, proliferation and differentiation of primary osteoblast-like cells

Surface acoustic waves (SAWs) have been used as a rapid and efficient technique for driving microparticles into a three-dimensional scaffold matrix, raising the possibility that SAW may be effective in seeding live cells into scaffolds, that is, if the cells were able to survive the infusion process. Primary osteoblast-like cells were used to specifically address this issue: To investigate the effects of SAW on the cells’ viability, proliferation, and differentiation. Fluorescence-labeled osteoblast-like cells were seeded into polycaprolactone scaffolds using the SAW method with a static method as a control. The cell distribution in the scaffold was assessed through image analysis. The cells were far more uniformly driven into the scaffold with the SAW method compared to the control, and the seeding process with SAW was also significantly faster: Cells were delivered into the scaffold in seconds compared to the hour-long process of static seeding. Over 80% of the osteoblast-like cells were found to be viable after being treated with SAW at 20 MHz for 10–30 s with an applied power of 380 mW over a wide range of cell suspension volumes (10–100 μℓ) and cell densities (1000–8000 cells∕μℓ). After determining the optimal cell seeding parameters, we further found that the treated cells offered the same functionality as untreated cells. Taken together, these results show that the SAW method has significant potential as a practical scaffold cell seeding method for tissue and orthopedic engineering

GRACILE Syndrome, a Lethal Metabolic Disorder with Iron Overload, Is Caused by a Point Mutation in BCS1L

GRACILE (growth retardation, aminoaciduria, cholestasis, iron overload, lactacidosis, and early death) syndrome is a recessively inherited lethal disease characterized by fetal growth retardation, lactic acidosis, aminoaciduria, cholestasis, and abnormalities in iron metabolism. We previously localized the causative gene to a 1.5-cM region on chromosome 2q33-37. In the present study, we report the molecular defect causing this metabolic disorder, by identifying a homozygous missense mutation that results in an S78G amino acid change in the BCS1L gene in Finnish patients with GRACILE syndrome, as well as five different mutations in three British infants. BCS1L, a mitochondrial inner-membrane protein, is a chaperone necessary for the assembly of mitochondrial respiratory chain complex III. Pulse-chase experiments performed in COS-1 cells indicated that the S78G amino acid change results in instability of the polypeptide, and yeast complementation studies revealed a functional defect in the mutated BCS1L protein. Four different mutations in the BCS1L gene have been reported elsewhere, in Turkish patients with a distinctly different phenotype. Interestingly, the British and Turkish patients had complex III deficiency, whereas in the Finnish patients with GRACILE syndrome complex III activity was within the normal range, implying that BCS1L has another cellular function that is uncharacterized but essential and is putatively involved in iron metabolism

A Founder Mutation in PET100 Causes Isolated Complex IV Deficiency in Lebanese Individuals with Leigh Syndrome

Leigh syndrome (LS) is a severe neurodegenerative disorder with characteristic bilateral lesions, typically in the brainstem and basal ganglia. It usually presents in infancy and is genetically heterogeneous, but most individuals with mitochondrial complex IV (or cytochrome c oxidase) deficiency have mutations in the biogenesis factor SURF1. We studied eight complex IV-deficient LS individuals from six families of Lebanese origin. They differed from individuals with SURF1 mutations in having seizures as a prominent feature. Complementation analysis suggested they had mutation(s) in the same gene but targeted massively parallel sequencing (MPS) of 1,034 genes encoding known mitochondrial proteins failed to identify a likely candidate. Linkage and haplotype analyses mapped the location of the gene to chromosome 19 and targeted MPS of the linkage region identified a homozygous c.3G>C (p.Met1?) mutation in C19orf79. Abolishing the initiation codon could potentially still allow initiation at a downstream methionine residue but we showed that this would not result in a functional protein. We confirmed that mutation of this gene was causative by lentiviral-mediated phenotypic correction. C19orf79 was recently renamed PET100 and predicted to encode a complex IV biogenesis factor. We showed that it is located in the mitochondrial inner membrane and forms a ∼300 kDa subcomplex with complex IV subunits. Previous proteomic analyses of mitochondria had overlooked PET100 because its small size was below the cutoff for annotating bona fide proteins. The mutation was estimated to have arisen at least 520 years ago, explaining how the families could have different religions and different geographic origins within Lebanon