SYNOVIAL FLUID PROFILE DICTATES NANOPARTICLE UPTAKE INTO CARTILAGE - IMPLICATIONS OF THE PROTEIN CORONA FOR NOVEL ARTHRITIS TREATMENTS

Objective: Drug delivery strategies for joint diseases need to overcome the negatively charged cartilage matrix. Previous studies have extensively investigated particle approaches to increase uptake efficiency by harnessing the anionic charge of the cartilage but have neglected to address potential interactions with the protein-rich biological environment of the joint space. We aimed to evaluate the effects of hard protein coronas derived from osteoarthritis (OA) and rheumatoid arthritis (RA) patient synovial fluids as well as the commonly used fetal calf serum (FCS) on nanoparticle (NP) uptake into tissues and cells. Methods: We developed a NP panel with varying PEGylation and incubated them with synovial fluid from either OA, RA patients or FCS. We evaluated the effects of the formed NP-biocorona complex uptake into the porcine articular cartilage explants, chondrocytes and monocyte cell lines and primary patient FLS cells. Proteins composing hard biocoronas were identified using a quantitative proteomics approach. Results: Formed biocoronas majorly impacted NP uptake into cartilage tissue and dictated their uptake in chondrocytes and monocytes. The most suitable NP for potential OA applications was identified. A variety of proteins that were found on all NPs, irrespective of surface modifications. NP-, and protein-specific differences were also observed between the groups, and candidate proteins were identified that could account for the observed differences. Conclusions: This study demonstrates the impact of protein coronas from OA and RA patient synovial fluids on NP uptake into cartilage, emphasizing the importance of biological microenvironment considerations for successful translation of drug delivery vehicles into clinics

Activated low-density granulocytes in peripheral and intervillous blood and neutrophil inflammation in placentas from SLE pregnancies

Objective Women with SLE face an increased risk of adverse pregnancy outcomes compared with healthy women, but the underlying immunological mechanisms are unknown. Given the recognised association of neutrophil activation with SLE pathogenesis, we examined whether there is increased neutrophil activation and inflammation in blood and placenta in SLE relative to healthy pregnancy. Methods At delivery, peripheral blood, maternal-derived intervillous blood and placentas were collected from 12 SLE and 10 healthy control pregnancies. The proportion of low-density granulocytes (LDGs) and the activation status of LDG and normal-density granulocytes were examined with flow cytometry. The chemokines CXCL8 and CXCL1 were quantified with a cytometric bead-based assay and interferon alpha (IFN alpha) protein levels with a Simoa method. IFN alpha-stimulated maternal-derived decidual stromal cells were examined for CXCL8 gene expression with qPCR. A pathologist, blinded to the patient background, examined all placentas. Results Women with SLE had significantly higher proportions of LDG in peripheral blood compared with controls (p=0.02), and LDG in both peripheral and intervillous blood were more activated in SLE relative to healthy pregnancies (peripheral blood: p=0.002 and intervillous blood: p=0.05). There were higher levels of CXCL8 and CXCL1 in intervillous compared with peripheral blood in women with SLE (p=0.004 and p=&amp;lt;0.0001, respectively) but not in controls. In SLE pregnancy, IFN alpha was detectable in 6 out of 10 intervillous blood samples but only in one control. Stimulation with IFN alpha upregulated CXCL8 gene expression in decidual stromal cells from both SLE and healthy pregnancy. Histological chorioamnionitis was present in 6 out of 12 placentas from women with SLE and in 1 out of 10 controls. Conclusions In women with SLE, locally produced chemokines in the placenta are increased and may attract and activate neutrophils. This in turn could contribute to placental inflammation and dysfunction and increased risk of placenta-related pregnancy complications.Funding Agencies|Swedish government; county councils; ALF agreement; Swedish Rheumatism Association; Gothenburg Society of Medicine; Ingegerd Johanssons Donation; foundations of King Gustaf Vs 80th Anniversary; Queen Victorias Freemasons; Swedish Research CouncilSwedish Research CouncilEuropean Commission</p

The evolutionary history of the common chloroplast genome of Arabidopsis thaliana and A. suecica

The evolutionary history of the common chloroplast (cp) genome of the allotetraploid Arabidopsis suecica and its maternal parent A. thaliana was investigated by sequencing 50 fragments of cpDNA, resulting in 98 polymorphic sites. The variation in the A. suecica sample was small, in contrast to that of the A. thaliana sample. The time to the most recent common ancestor (T(MRCA)) of the A. suecica cp genome alone was estimated to be about one 37th of the T(MRCA) of both the A. thaliana and A. suecica cp genomes. This corresponds to A. suecica having a MRCA between 10 000 and 50 000 years ago, suggesting that the entire species originated during, or before, this period of time, although the estimates are sensitive to assumptions made about population size and mutation rate. The data was also consistent with the hypothesis of A. suecica being of single origin. Isolation-by-distance and population structure in A. thaliana depended upon the geographical scale analysed; isolation-by-distance was found to be weak on the global scale but locally pronounced. Within the genealogical cp tree of A. thaliana, there were indications that the root of the A. suecica species is located among accessions of A. thaliana that come primarily from central Europe. Selective neutrality of the cp genome could not be rejected, despite the fact that it contains several completely linked protein-coding genes