Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “immunization”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 991 records · Page 55

Effect of calcium carbonate particle shape on phagocytosis and pro-inflammatory response in differentiated THP-1 macrophages

Phagocytosis is a physiological process used by immune cells such as macrophages to actively ingest and destroy foreign pathogens and particles. It is the cellular process that leads to the failure of drug delivery carriers because the drug carriers are cleared by immune cells before reaching their target. Therefore, clarifying the mechanism of particle phagocytosis would have a significant implication for both fundamental understanding and biomedical engineering. As far as we know, the effect of particle shape on biological response has not been fully investigated. In the present study, we investigated the particle shape-dependent cellular uptake and biological response of differentiated THP-1 macrophages by using calcium carbonate (CaCO{sub 3})-based particles as a model. Transmission electron microscopy analysis revealed that the high uptake of needle-shaped CaCO{sub 3} particles by THP-1 macrophages because of their high phagocytic activity. In addition, the THP-1 macrophages exposed to needle-shaped CaCO{sub 3} accumulated a large amount of calcium in the intracellular matrix. The enhanced release of interleukin-8 (IL-8) and tumor necrosis factor-alpha (TNF-α) by the THP-1 macrophages suggested that the needle-shaped CaCO{sub 3} particles trigger a pro-inflammatory response. In contrast, no pro-inflammatory response was induced in undifferentiated THP-1 monocytes exposed to either needle- or cuboidal-shaped CaCO{sub 3} particles, probably because of their low phagocytic activity. We also found that phosphate-coated particles efficiently repressed cellular uptake and the resulting pro-inflammatory response in both THP-1 macrophages and primary peritoneal macrophages. Our results indicate that the pro-inflammatory response of macrophages upon exposure to CaCO{sub 3} particles is shape- and surface property-dependent, and is mediated by the intracellular accumulation of calcium ions released from phagocytosed CaCO{sub 3} particles. - Highlights: • Needle-shaped CaCO{sub 3} particles are phagocytized by macrophages. • Needle-shaped CaCO{sub 3} particles induce intracellular accumulation of calcium ions. • Needle-shaped CaCO{sub 3} particles induce pro-inflammatory responses. • Surface-coating with phosphate decreases adverse effects on macrophages.

60 APPLIED LIFE SCIENCES↗

Quantitative proteome analysis of bovine mammary gland reveals protein dynamic changes involved in peak and late lactation stages

Highlights: • Revealed dynamic protein changes between two lactation stages in bovine mammary by TMT-based proteomics (first time). • Longitudinal design avoided the influence of different genetic backgrounds on the DEP detection. • 179 differentially expressed proteins (DEPs) identified. • Identified novel DEPs: AACS, DHCR7, GSTM3, SFRP1 and SFRP4. • Major pathways: PI3K-Akt, localization, lipid metabolic, amino acid transport immune system and apoptotic signaling. Mammary gland is an important organ for milk synthesis and secretion. It undergoes dramatic physiological changes to adapt the shift from peak to late lactation stage. Protein plays a final very vital role in many life functions, and the protein changes during different lactation stages potentially reflect the biology of lactation and the functions of mammary gland in cows. In current study, we adopted tandem mass tags label-based quantitative analysis technique and to investigate proteome changes occurring in bovine mammary gland from peak to late lactation stages. A total of 3753 proteins from mammary tissues taken at two lactation points from four individual cows by biopsy were quantified, out of which 179 proteins were expressed differentially between two stages. We observed five new DEPs (AACS, DHCR7, GSTM3, SFRP1 and SFRP4) and nine functional well-studies known proteins (PLIN2, LPIN1, PLIN3, GSN, CD74, MMP2, SOD1, SOD3 and GPX3) related to milk performance and mammary morphology. Bioinformatics analyses of the DEPs showed a majority of the up-regulated proteins during late lactation stage were related to apoptosis and immune process, while the downregulated proteins were mainly involved in localization, lipid metabolic and transport process. This suggests that the mammary gland can adapt to different molecular functions according to the biological need of the animal. From the integrated analysis of the differentially expressed proteins with known quantitative trait loci and genome-wide association study data, we identified 95 proteins may potentially affect milking performance. We expect findings in this study could be a valuable resource for future studies investigating the bovine proteome and functional studies.

60 APPLIED LIFE SCIENCES↗

PACT is required for MDA5-mediated immunoresponses triggered by Cardiovirus infection via interaction with LGP2

Laboratory of genetics and physiology 2 (LGP2) and melanoma differentiation-associated gene 5 (MDA5) cooperatively detect viral RNA in the cytoplasm of Cardiovirus-infected cells and activate innate immune responses. Here, we evaluated whether the double-stranded RNA-binding protein PACT plays a role in this anti-viral response to further elucidate the mechanism. Immunoprecipitation experiments demonstrated that PACT interacts with LGP2 and that this interaction is enhanced by encephalomyocarditis virus (EMCV) infection. In vitro interaction analyses using purified recombinant proteins confirmed that the single-stranded Theiler's murine encephalitis virus genome enhanced the interaction between LGP2 and PACT. Small interfering RNA knockdown experiments further indicated that PACT is required for Cardiovirus-triggered interferon responses. To support this functional interaction with LGP2, overexpressed PACT was shown to enhance EMCV-triggered interferon promoter activity only when LGP2 and MDA5 were co-expressed but not when MDA5 is expressed alone. Together, our findings indicate a possible role of PACT in regulating the Cardiovirus-triggered immune responses mediated by MDA5 and LGP2, which opens the door to novel therapeutic strategies in interferon-related autoimmune diseases and cancer.

60 APPLIED LIFE SCIENCES↗

CD1d is a novel cell-surface marker for human monocytic myeloid-derived suppressor cells with T cell suppression activity in peripheral blood after allogeneic hematopoietic stem cell transplantation

Highlights: • High-content screening identified a set of cell-surface marker candidates expressed in HLA-DR{sup -}CD14{sup +} M-MDSCs. • CD1d and CD226 are novel markers for the human M-MDSC subset. • CD1d-expressing M-MDSC showed the suppressive activity of T cell proliferation and could be a valuable marker for of human M-MDSCs. Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of cells that regulate immune responses in cancer and various pathological conditions. However, the phenotypic and functional heterogeneity of human MDSCs represents a major hurdle for the development of therapeutic strategies targeting or regulating MDSCs in tumor progression, inflammation, and graft-versus-host disease (GVHD). We previously shown that circulating HLA-DR{sup -}CD14{sup +} monocytic MDSCs are a major contributor to clinical outcomes after allogeneic hematopoietic stem cell transplantation (allo-HSCT). In this study, we identified, using high-throughput screening, a set of surface markers that are strongly expressed in HLA-DR{sup -}CD14{sup +} monocytic MDSCs isolated from the peripheral blood (PB) of patients receiving allo-HSCT. Subsequent experiments showed the consistent dominant expression of CD1d in monocytic MDSCs of allo-HSCT PB in comparison with granulocytic MDSCs. In addition, CD1d-expressing cells isolated from PB of allo-HSCT patients showed the suppressive activity of T cell proliferation and higher expression of MyD88 and IDO compared with CD1d{sup −} cells. Our results suggest that CD1d could be a valuable marker for further therapeutic evaluation of human monocytic MDSCs for immune-related diseases, including GVHD.

60 APPLIED LIFE SCIENCES↗

Endothelial Robo4 regulates IL-6 production by endothelial cells and monocytes via a crosstalk mechanism in inflammation

Highlights: • Robo4 knockout in mouse endotoxemia models reduced circulating IL-6 levels. • Robo4 knockdown suppressed IL-6 and GM-CSF production by endothelial cells (ECs). • Robo4 enhanced IL-6 production by monocytes via EC-derived GM-CSF. • Robo4 regulates cytokine production by both ECs and immune cells in inflammation. Roundabout4 (Robo4) is an endothelial cell-specific receptor that stabilizes vasculature in pathological angiogenesis. Previous studies have shown that Robo4 is a potential therapeutic target for inflammatory diseases, but its precise roles in inflammation remain unclear. To investigate physiological Robo4 functions in inflammation, we performed a loss-of-function study in vitro and in vivo using lipopolysaccharide (LPS)-induced endotoxemia models. Subcutaneous injection of LPS into Robo4-knockout mice reduced circulating IL-6 levels. siRNA-mediated Robo4 knockdown suppressed IL-6 production induced by LPS, IL-1β, and TNFα, in human umbilical vein endothelial cells (HUVECs). Coculture experiments with HUVECs and a monocytic cell line, U937 cells, demonstrated that Robo4 knockdown suppresses IL-6 production by both endothelial cells and U937 cells. Further coculture experiments demonstrated that Robo4 knockdown inhibited a novel IL-6 amplification mechanism mediated by crosstalk between endothelial cells and U937 cells via direct interactions and two mediators, GM-CSF and IL-1β. Taken together, we demonstrated novel Robo4 functions in inflammation, i.e., it promotes IL-6 production by endothelial cells and immune cells via crosstalk.

60 APPLIED LIFE SCIENCES↗

NK cell and IFN signatures are positive prognostic biomarkers for resectable pancreatic cancer

Highlights: • Integrative immunomonitoring was undertaken in resected pancreatic cancer patients. • Immunomonitoring employed flow cytometry, multiplex-bead assays and RMA-Seq. • Higher NK cell % in peripheral blood are associated with better prognosis. • Type I and II IFN signatures in the tumor are associated with better prognosis. • Epithelial mesenchymal transition is associated with early recurrence. To establish prognostic biomarkers and to identify potential novel therapeutic targets, we performed integrative immunomonitoring of blood and tumor in patients with resectable pancreatic cancer. Flow cytometry (FC) was employed for phenotyping immune cells, multiplex bead assays for plasma cytokine and chemokine determination, and RNA-Seq for the analysis of gene expression in the tumor. Nineteen pancreatic cancer patients were stratified into those with longer or shorter than median recurrence-free survival after surgery (median, 426 days). There were no significant differences between the two groups for clinical parameters including age, sex, surgical procedure, stage, or postoperative adjuvant therapy. However, we found that the percentages of NK cells as assessed by FC in peripheral blood mononuclear cells were higher in patients with late recurrence (P = .037). RNA-Seq data indicated no differences in the amount of immune cells or stromal cells between the two groups, although NK cells in the tumor did tend to be higher in patients with late recurrence (P = .058). Type I and II IFN signatures were enriched in late-recurring tumors (FDR q-value <0.001), while genes related to KRAS signaling and the epithelial mesenchymal transition (EMT) were enriched in early recurrence. We conclude that tumor-intrinsic properties of metastasis and recurrence influence prognosis, whereas NK cells that might contribute to prevent metastasis are associated with longer recurrence-free survival. Therefore, enhancement of NK cell activity and inhibition of the EMT and KRAS signaling might represent appropriate therapeutic targets following surgical resection of pancreatic cancer.

60 APPLIED LIFE SCIENCES↗

Prolonged skin grafts survival time by IFN-γ in allogeneic skin transplantation model during acute rejection through IFN-γ/STAT3/IDO pathway in epidermal layer

Allogeneic skin transplantation is the life-saving therapy for multiple diseases, including extensive burn, large-scale trauma and certain post-surgical complications. However, acute rejection impedes clinical application of allogeneic skin transplantation. Although a lot of novel immunosuppressant drugs have been developed, there is still great need for ideal therapy with less complication and more therapeutic effects. Here, we found interferon gamma (IFN-γ) as an immunomodulatory cytokine prolonged the survival time of allografts from (8.50 ± 1.517) days to (14.83 ± 2.714) days at best. Indoleamine-2, 3-dioxygenase (IDO) has been proposed to play key roles in induction of immune tolerance. Using in vitro tissue culture and primary keratinocytes and fibroblasts, we investigated the regulatory effects of IFN-γ on the IDO expression. IFN-γ upregulated IDO expression through STAT3 phosphorylation and this upregulation was reduced by abolition of STAT3 phosphorylation through a STAT3 phosphorylation inhibitor. Interestingly, IFN-γ induced IDO expression predominately in epidermis rather than dermis. In consistent with these results, IFN-γ significantly triggered IDO expression in keratinocytes but not fibroblasts. Taken together, this suggests that IFN-γ might be a potential immunomodulatory drug in acute rejection and keratinocytes in epidermis may play a main role in immune tolerance after allogeneic skin transplantation.

60 APPLIED LIFE SCIENCES↗

Zika virus infected primary microglia impairs NPCs proliferation and differentiation

Highlights: • ZIKV infects primary microglia and induce inflammatory response. • ZIKV infected microglia decreases NPCs proliferation. • ZIKV infected microglia promote astrogenesis at the expense of neurogenesis. • Cytokines secreted by ZIKV infected microglia decrease neurogenesis. Zika virus (ZIKV) can lead to severe birth defects especially microcephaly in newborns by infecting human neural progenitors and impairing brain development. However, as the resident immune cells in the brain, the role of microglia in the ZIKV pathology is not clearly defined. To understand the interplay between immune response and neural cells, we investigate the interaction between microglia and NPCs during ZIKV infection. Our results demonstrate that primary microglia infected with ZIKV induces an inflammatory response similar to that in human, producing high level of tumor necrosis factor alpha (TNF-α), interleukin 6 (IL-6), interleukin 1β (IL-1β) and inducible nitric oxide synthase (iNOS). Furthermore, conditional medium (CM) of ZIKV infected microglia showed inhibitory effects on cell proliferation and neuronal differentiation of neural precursor cells (NPCs) derived from E14 mice brain. Blocking cytokines in the CM remarkably improved neurogenesis and decreased astrocytic differentiation of NPCs. Together, our results suggest that microglia mediated neuroinflammation plays an important role in neuropathogenesis during ZIKV infection.

60 APPLIED LIFE SCIENCES↗

Structural basis of the cystein protease inhibitor Clonorchis sinensis Stefin-1

Highlights: • Clonorchis sinensis Stefin-1 has known as a host immune modulator. • The first crystal structure of CsStefin-1 was determined by the MAD method. • CsStefin-1 inhibited CsCF-8 cysteine protease activity. • A molecular docking model of CsStefin-1 and CsCF-8 was developed. • The CsStefin-1 was physically bound to CsCF-8 with an apparent K{sub D} value. Cystein protease plays a critical role as a virulence factor in the development and progression of various diseases. Cystatin is a superfamily of cysteine protease inhibitors that participates in various physiological and pathological processes. The cysteine protease inhibitor CsStein-1 isolated from Clonorchis sinensis belongs to the type 1 stefin of cystatins. This inhibitor regulates the activity and processing of CsCF (Cathepsin F of Clonorchis sienesis), which plays an important role in parasite nutrition and host-parasite interaction. CsStefin-1 has also been proposed as a host immune modulator and a participant in the mechanism associated with anti-inflammatory ability. Here, we report the first crystal structure of CsStefin-1 determined by the multi-wavelength anomalous diffraction (MAD) method to 2.3 Å. There are six molecules of CsStefin-1 per asymmetric unit, with a solvent content of 36.5%. The structure of CsStefin-1 is composed of twisted four-stranded antiparallel β-sheets, a central α-helix, and a short α-helix. We also demonstrate that CsStefin-1 binds to CsCF-8 cysteine protease and inhibits its activity. In addition, a molecular docking model of CsStefin-1 and CsCF-8 was developed using homology modeling based on their structures. The structural information regarding CsStefin-1 and molecular insight into its interaction with CsCF-8 are important to understanding their biological function and to design of inhibitors that modulate cysteine protease activity.

60 APPLIED LIFE SCIENCES↗

Micro124-mediated AHR expression regulates the inflammatory response of chronic rhinosinusitis (CRS) with nasal polyps

Highlights: • MiR124 and AHR play very important roles in the inflammatory response. • MiR124 can inhibit AHR expression by directly target 3′ untranslated region (3′-UTR) of AHR. • MiR124 could regulates cellular inflammatory response through negatively regulating AHR expression. MicroRNAs represent a component of the innate immune responses that can restrain inflammatory signaling, miR124 is an important member of inflammation-associated miRNAs, and abnormal miR124 expression is observed in many inflammatory diseases and immune disorders. However, the role and signaling pathways of miR124 in chronic rhinosinusitis with nasal polyps (CRSwNPs) have not been studied in detail. The aryl hydrocarbon receptor (AHR) is a ligand-inducible transcription factor that is highly conserved in evolution and plays important roles in the inflammatory response process. In our study, we describe the role of miR124 in the inflammatory response of CRS with nasal polyps. We found that the expression of miR124 was decreased in nasal polyps, and negatively correlated with the expression of AHR. MiR124 can inhibit AHR expression by directly target 3′ untranslated region (3′-UTR) of AHR. To further investigate the relationship between miR124, AHR and CRS inflammatory response, we transfect HNEpC cells with miR124 mimic, miR124 inhibitors or siRNA of AHR, then all the results showed that miR124 could regulates cellular inflammatory response through negatively regulating AHR expression. This study demonstrated that the regulation of AHR expression by miR124 is critical to the development of inflammatory response in CRSwNPs.

60 APPLIED LIFE SCIENCES↗

TREM2 modulates microglia phenotypes in the neuroinflammation of Parkinson's disease

Highlights: • TREM2, Arginase-1 and proinflammatory cytokines increased in the midbrain of PD mice. • Knockdown of TREM2 in BV2 microglia exaggerated M1 microglial inflammatory responses. • TREM2 overexpression promoted M2 polarization and alleviated microglial inflammation. • TREM2 plays a crucial role in altering M1 microglia to M2 phenotype. Neuroinflammation and overactivated microglia underlies the pathogenesis of Parkinson's disease (PD). Furthermore, microglia could polarize into classic inflammatory M1 and immunosuppressive M2 phenotype. Thus, inhibiting the overactivated inflammatory M1 microglia by promoting the transformation of microglia to the protective M2 phenotype provides potential therapy for PD, but the mechanism that modulates microglia polarization remains unknown. Triggering receptor expressed on myeloid cells-2 (TREM2) is a recently identified immune receptor expressed by the microglia in the brain. Emerging evidence indicates that TREM2 enhances the phagocytosis function of microglia and suppress inflammation. Based on these evidence, we hypothesized that TREM2 might play a protective role through regulating microglia polarization. Here, we employ a lentiviral strategy to overexpress or suppress TREM2 on microglia and found that TREM2 was essential for M2 microglia polarization. Knockdown of TREM2 in BV2 microglia inhibited M2 polarization and lead to exaggeration of M1 microglial inflammatory responses, whereas overexpression of TREM2 promoted M2 polarization and alleviated microglial inflammation. We also observed that the TREM2 level was higher in the midbrain of PD mice, which was accompanied by an elevated level of Arginase-1 and increased proinflammatory cytokines, suggesting that TREM2 is an important factor in switching the microglia phenotypes. Taken together, these findings indicate that TREM2 plays a crucial role in altering the proinflammatory M1 microglia to M2 phenotype and has beneficial effects in the immune pathogenesis of PD.

60 APPLIED LIFE SCIENCES↗

Exosomal proteome analysis of human plasma to monitor sepsis progression

Highlights: • As low as 300 μL human plasma is sufficient for exosome isolation using our one-step density gradient ultracentrifugation. • Protein profiling of septic plasma exosomes are closely related to immune responses. • SPTLC3 may play important roles in development of sepsis. Exosomes are cell-derived vesicles containing RNA, lipid, and protein, which act in body immune response, intercellular signaling and some other important biological processes. Exosomes have been extensively studied in the past several years on their disease related mechanisms and potential roles to monitor disease progression as biomarkers. Compared with analyzing exosome RNA, comprehensive proteome profiling of exosomes in clinical samples (e.g. blood) are highly demanded but limited mainly due to lack of a reproducible method for efficient exosome extraction. In this study, we evaluated and optimized an exosome preparation approach using one-step ultracentrifugation through an Optiprep™ cushion. Exosomes prepared via this method and analyzed by mass spectrometry using Q-Exactive plus, has led to reproducible identification and quantification of 200 + proteins from human plasma samples of as little as 300 μL. Therefore, such a straightforward exosome extract method has enable us to deeply profile exosome proteomes from human blood at a scale of clinical studies. As a proof of principal, we practiced this approach in analyzing the exosome proteomic profiles of blood samples collected from a sepsis patient during six time points after diagnosis. Among the 238 proteins identified and quantified across the 6 samples, protein SPTLC3 involved in the sphingolipid metabolism, shows a negative correlation (p = 0.02, correlation coefficient = −0.984) with disease progression indicated by body temperature (BD) and C-reactive protein (CRP). Therefore, SPTLC3 could be an interesting target for future study on molecular mechanism of sepsis development, as well as potential classifier to monitor clinical progression of sepsis.

60 APPLIED LIFE SCIENCES↗

Frequencies and expression levels of programmed death ligand 1 (PD-L1) in circulating tumor RNA (ctRNA) in various cancer types

Highlights: • Blood were collected from gastric, colorectal, lung, breast, prostate cancer patients. • PD-L1 expression was detected in the plasma at varying frequencies. • No PD-L1 mRNA was detected in cancer-free individuals. • PD-L1 mRNA can be detected and quantitated in ctRNA of cancer patients. Precision medicine and prediction of therapeutic response requires monitoring potential biomarkers before and after treatment. Liquid biopsies provide noninvasive prognostic markers such as circulating tumor DNA and RNA. Circulating tumor RNA (ctRNA) in blood is also used to identify mutations in genes of interest, but additionally, provides information about relative expression levels of important genes. In this study, we analyzed PD-L1 expression in ctRNA isolated from various cancer types. Tumors inhibit antitumor response by modulating the immune checkpoint proteins programmed death ligand 1 (PD-L1) and its cognate receptor PD1. The expression of these genes has been implicated in evasion of immune response and resistance to targeted therapies.

60 APPLIED LIFE SCIENCES↗

YY1 promotes IL-6 expression in LPS-stimulated BV2 microglial cells by interacting with p65 to promote transcriptional activation of IL-6

Neuroinflammation plays a critical role in the process of neurodegenerative disorders, during which microglia, the principal resident immune cells in the central nervous system, are activated and produce proinflammatory mediators. Yin-Yang 1 (YY1), a multi-functional transcription factor, is widely expressed in cells of the immune system and participate in various cellular processes. However, whether YY1 is involved in the process of neuroinflammation is still unknown. In the present study, we found that YY1 was progressively up-regulated in BV2 microglial cells stimulated with lipopolysaccharide (LPS), which was dependent on the transactivation function of nuclear factor kappa B (NF-κB). Furthermore, YY1 knockdown notably inhibited LPS-induced the activation of NF-κB signaling and interleukin-6 (IL-6) expression in BV-2 cells, but not mitogen-activated protein kinase (MAPK) signaling. Moreover, YY1 strengthened p65 binding to IL-6 promoter by interacting with p65 but decreased H3K27ac modification on IL-6 promoter, eventually increasing IL-6 transcription. Taken together, these results for the first time uncover the regulatory mechanism of YY1 on IL-6 expression during neuroinflammation responses and provide new lights into neuroinflammation.

60 APPLIED LIFE SCIENCES↗

PDGF family function and prognostic value in tumor biology

Highlights: • Large scale transcriptomic data analysis reveals tumor-specific roles of PDGF signaling. • Functional gene sets associated with PDGF expression are conserved between PDGF family members. • PDGF related gene signatures have increased prognostic value over each single gene. The development and progression of a tumor depends on the close interaction of malignant cells and the supportive and suppressive tumor microenvironment. Paracrine signaling enables tumor cells to shape the surrounding tissue in order to decrease recognition by the immune system, attract blood vessels to fuel growth, change metabolic programs, and induce wound healing programs. In this study, we investigate the role of the platelet-derived growth factor (PDGF) family members PDGFA, PDGFB, PDGFC and PDGFD and their cognate tyrosine kinase receptors PDGFRA and PDGFRB, using publicly available data from The Cancer Genome Atlas and the Human Protein Atlas. Large scale analysis of expression correlation in RNA sequencing data from 7616 samples derived from 16 tumor types, revealed conserved functional programs in PDGF signaling in the majority of solid tumor types. Besides the well-known effects of PDGF signaling in mesenchymal cells, our analyses revealed a potential role of PDGF signaling in the composition of the immune microenvironment. We furthermore derived gene signatures with increased prognostic value for each PDGF family member. This study emphasizes the potential to impinge on specific paracrine signaling events to interfere with the crosstalk between malignant cells and their microenvironment.

60 APPLIED LIFE SCIENCES↗

Identification of antibodies against extracellular matrix proteins in human osteoarthritis

Highlights: • Autoantibodies against the TSP-4, COMP and CLEC3A are present in serum of osteoarthritis (OA) patients. • The detection of autoantibodies against TSP-4, COMP and CLEC3A may support the clinical diagnosis of OA. • OA with autoantibodies against cartilage extracellular matrix proteins defines a new OA subgroup. • Patients with high concentrations of autoantibodies may benefit from an immune suppressive therapy. We investigated the presence of autoantibodies against the extracellular matrix proteins thrombospondin-4 (TSP-4), cartilage oligomeric matrix protein (COMP), C-type lectin domain family 3 member A (CLEC3A), collagen II, collagen VI, matrilin-3, and fibrillin-2 in the serum of osteoarthritis (OA) patients. We compared those results with the presence of such antibodies in rheumatoid arthritis (RA) patients and in healthy donors (HD). Our study examines whether antibodies against extracellular proteins can be used as potential biomarkers to support the clinical diagnosis of OA. 10 OA, 10 RA patients and 10 HD were enrolled in this explorative cross-sectional study. SDS-PAGE and immunoblot were used to investigate the presence of antibodies against extracellular matrix proteins. The serum of 5/10 OA patients but 0/10 HD exhibited TSP-4 IgG isotype antibodies (P = 0.033). The serum of 8/10 OA patients but only 1/10 HD exhibited IgG isotype antibodies against TSP-4 or COMP (P = 0.005). The serum of 9/10 OA patients but only 1/10 HD exhibited IgG isotype antibodies against TSP-4, COMP or CLEC3A (P = 0.005). We found strong evidence for the presence of IgG isotype autoantibodies against the cartilage extracellular matrix proteins TSP-4, COMP and CLEC3A in OA. The detection of IgG isotype autoantibodies against TSP-4, COMP and CLEC3A may support the clinical diagnosis of OA. OA with autoantibodies against cartilage extracellular matrix proteins defines a new OA subgroup suggesting that patients with high concentrations of autoantibodies may benefit from an immune suppressive therapy.

60 APPLIED LIFE SCIENCES↗

The ferroptosis inducer erastin promotes proliferation and differentiation in human peripheral blood mononuclear cells

Peripheral blood mononuclear cells (PBMCs) contain multipotent progenitor cell populations and possess the potential to differentiate into various types of immune cells under both physiological and pathological conditions. Ferroptosis is a type of oxidative stress-associated cell death that is mainly mediated by lipid peroxidation. However, the function of ferroptosis in cell differentiation remains unknown. Here, we showed that the ferroptosis inducer erastin did not cause cell death in human PBMCs. In contrast, erastin-induced lipid peroxidation promoted human PBMC proliferation and differentiation into B cells and natural killer cells through inhibition of bone morphogenetic protein family expression. These findings uncover a new immune modulation function of erastin in promoting PBMC proliferation and differentiation.

60 APPLIED LIFE SCIENCES↗

Anti-survivin single-domain antibodies derived from an artificial library including three synthetic random regions by in vitro selection using cDNA display

Highlights: • Single-domain antibodies can be selected with an artificial DNA library synthesized chemically. • cDNA display method is useful for in vitro selection from a large single-domain antibodies library (e.g. 1013). • A Brevibacillus protein expression system is suitable for synthesis of functional single-domain antibodies. Single-domain antibodies (variable domain of the heavy chain of a heavy chain antibody; VHH) are promising reagents for therapeutics and diagnostics because of their stability, cost-effective production and material workability as a small antibody. Currently, general acquisition of a VHH using immunization of camelids is inconvenient from the standpoint of animal protection, cost and the process is time-consuming. Thus, a straightforward and efficient method for screening VHHs against a target molecule is required. In this study, we examined whether in vitro selection of a VHH against a target protein could be performed by a cDNA display method with an artificial VHH library that had the three complementarity-determining regions (CDRs) randomized by chemical synthesis. The results revealed that a particular VHH against survivin, which is a member of the inhibitor of apoptosis family, was selected with affinity in the range of 10{sup −7} to 10{sup −8} M. The in vitro selection of a VHH using cDNA display with an artificial synthesized library without animal immunization was shown to be effective for rapid and inexpensive screening of VHHs against a target protein.

60 APPLIED LIFE SCIENCES↗