Enzyme-linked Immunosorbent Assay Data Research Articles

Modified Biejia Jianwan decoction restrains PD-L1-mediated immune evasion through the HIF-1α/STAT3/NF-κB signaling pathway

Ethnopharmacological relevanceModified Biejia Jianwan (M-BJJW), a Traditional Chinese Medicine (TCM) decoction, has exhibited great potential in treating hepatocellular carcinoma (HCC). However, its underlying functional mechanism still remains unknown. Aim of the studyThe study aimed to explore the anti-hepatocarcinogenic effects of M-BJJW, specifically its influence on PD-L1-mediated immune evasion in hypoxic conditions, and elucidate the related molecular mechanisms in HCC. Materials and methodsTo investigate the therapeutic efficacy and mechanisms underlying M-BJJW's effects on HCC, we employed a diethylnitrosamine (DEN)-induced rat model maintained for 120 days. Following model establishment, flow cytometry was utilized to assess the distribution of immune cell populations in peripheral blood, spleens, and tumor tissues after M-BJJW administration. Simultaneously, enzyme-linked immunosorbent assays (ELISA) were conducted to analyze cytokine profiles in serum samples. Immunohistochemistry was employed to determine the expression levels of crucial proteins within tumor tissues. Furthermore, HCC cells exposed to CoCl2 underwent Western blot analysis to validate the expression levels of HIF-1α, PD-L1, STAT3, and nuclear factor kappa B (NF-κB) p65. The modulatory effects of STAT3 and NF-κB p65 were investigated using specific inhibitors and activators in wild-type cell lines. High-performance liquid chromatography coupled with mass spectrometry (HPLC/MS) was utilized to identify the chemical constituents present in M-BJJW-medicated serum. The immunomodulatory properties and the anti-tumor activities of M-BJJW were evaluated by co-culturing with peripheral blood mononuclear cells (PBMC) and the CCK-8 assay. Additionally, we assessed M-BJJW's impact on hypoxia-induced alterations in HCC cell lines using immunofluorescence and Western blot assessments. ResultsM-BJJW exhibited substantial therapeutic advantages by effectively alleviating pathological deterioration within the HCC microenvironment. In the DEN-induced rat model, M-BJJW administration notably reduced tumor growth. Flow cytometry analyses revealed an increased proportion of Cytotoxic T lymphocytes (CTLs) accompanied by a simultaneous decrease in regulatory T cells (Tregs). ELISA data supported a marked decrease in pro-inflammatory cytokines, including interleukin-6 (IL-6), interleukin-10 (IL-10), and tumor necrosis factor α (TNF-α). Immunohistochemistry confirmed the suppressive effect of M-BJJW on the expression of HIF-1α and PD-L1. Notably, western blotting unveiled the role of HIF-1α in regulating PD-L1 expression via the STAT3 and NF-κB signaling pathways in HCC cell lines, which was validated using activators and inhibitors of STAT3 and NF-κB. The CCK-8 assay and co-culture techniques demonstrated the anti-tumor activity of M-BJJW. Immunofluorescence and western blotting further confirmed that M-BJJW-containing serum dose-dependently inhibited HIF-1α, PD-L1, p-STAT3, and p-p65 in hypoxic HCC cell lines. ConclusionsM-BJJW demonstrates significant therapeutic potential against HCC by influencing the hypoxic microenvironment, thereby regulating the immunosuppressive milieu. Specifically, M-BJJW modulates the HIF-1α/STAT3/NF-κB signaling pathway, leading to reduced PD-L1 expression and an elevated ratio of cytotoxic T lymphocytes (CTLs), while concurrently decreasing T regulatory cells (Tregs) and immunosuppressive factors. These synergistic effects aid in countering PD-L1-mediated immune evasion, presenting compelling pharmacological evidence supporting the clinical application of M-BJJW as a therapeutic approach for HCC.

Detection and Quantification of Calcitonin Gene-Related Peptide (CGRP) in Human Plasma Using a Modified Enzyme-Linked Immunosorbent Assay

Calcitonin gene-related peptide (CGRP) is a vasoactive neuropeptide that plays a putative role in the pathophysiology of migraine headaches and may be a candidate for biomarker status. CGRP is released from neuronal fibers upon activation and induces sterile neurogenic inflammation and arterial vasodilation in the vasculature that receives trigeminal efferent innervation. The presence of CGRP in the peripheral vasculature has spurred investigations to detect and quantify this neuropeptide in human plasma using proteomic assays, such as the enzyme-linked immunosorbent assay (ELISA). However, its half-life of 6.9 min and the variability in technical details of assay protocols, which are often not fully described, have yielded inconsistent CGRP ELISA data in the literature. Here, a modified ELISA protocol for the purification and quantification of CGRP in human plasma is presented. The procedural steps involve sample collection and preparation, extraction using a polar sorbent as a means of purification, additional steps to block non-specific binding, and quantification via ELISA. Further, the protocol has been validated with spike and recovery and linearity of dilution experiments. This validated protocol can theoretically be used to quantify CGRP concentrations in the plasma of individuals not only with migraine, but also with other diseases in which CGRP may play a role.

SARS-CoV-2 infection-induced immunity and the duration of viral shedding: Results from a Nicaraguan household cohort study.

Much of the world's population has been infected with SARS-CoV-2. Thus, immunity from prior infection will play a critical role in future SARS-CoV-2 transmission. We investigated the impact of infection-induced immunity on viral shedding duration and viral load. We conducted a household cohort study in Managua, Nicaragua, with an embedded transmission study that closely monitors participants regardless of symptoms. Real-time reverse-transcription polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assays (ELISAs) were used to measure infections and seropositivity, respectively. Blood samples were collected twice annually and surrounding household intensive monitoring periods. We used accelerated failure time models to compare shedding times. Participants vaccinated ≥14 days prior to infection were excluded from primary analyses. There were 600 RT-PCR-confirmed SARS-CoV-2 infections in unvaccinated participants between May 1, 2020, and March 10, 2022, with prior ELISA data. Prior infection was associated with 48% shorter shedding times (event time ratio [ETR] 0.52, 95% CI: 0.39-0.69, mean shedding: 13.7 vs. 26.4days). A fourfold higher anti-SARS-CoV-2 spike titer was associated with 17% shorter shedding (ETR 0.83, 95% CI: 0.78-0.90). Similarly, maximum viral loads (lowest cycle threshold [CT]) were lower for previously infected individuals (mean CT 29.8 vs. 28.0, p = 4.02 × 10-3 ), for adults and children ≥10years, but not for children 0-9years; there was little difference in CT levels for previously infected versus naïve adults aged above 60 years. Prior infection-induced immunity was associated with shorter viral shedding and lower viral loads, which may be important in the transition from pandemic to endemicity.

Comprehensive analysis of key genes and pathways for biological and clinical implications in thyroid-associated ophthalmopathy

BackgroundThyroid-associated ophthalmopathy (TAO) is a common and organ-specific autoimmune disease. Early diagnosis and novel treatments are essential to improve the prognosis of TAO patients. Therefore, the current work was performed to identify the key genes and pathways for the biological and clinical implications of TAO through comprehensive bioinformatics analysis and a series of clinical validations.MethodsGSE105149 and GSE185952 were obtained from the Gene Expression Omnibus (GEO) database for analysis. The data were normalized to identify the common differentially expressed genes (DEGs) between the two datasets, and the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were conducted to assess key pathways in TAO. Protein–protein interaction (PPI) networks and hub genes among the common DEGs were identified. Furthermore, we collected the general information and blood samples from 50 TAO patients and 20 healthy controls (HCs), and the expression levels of the proteins encoded by hub genes in serum were detected by enzyme-linked immunosorbent assay (ELISA). Then we further assessed the relationship between the ELISA data and the TAO development.ResultsSeveral common pathways, including neuroactive ligand-receptor interaction, the IL-17 signaling pathway, and the TNF signaling pathway, were identified in both datasets. In parallel, 52 common DEGs were identified. The KEGG analysis showed that these common DEGs are mainly enriched in long-term depression, the VEGF signaling pathway, the IL-17 signaling pathway, the TNF signaling pathway, and cytokine-cytokine receptor interactions. The key hub genes PRKCG, OSM, DPP4, LRRTM1, CXCL6, and CSF3R were screened out through the PPI network. As confirmation, the ELISA results indicated that protein expression levels of PRKCG, OSM, CSF3R, and DPP4 were significantly upregulated in TAO patients compared with HCs. In addition, PRKCG and DPP4 were verified to show value in diagnosing TAO, and CSF3R was found to be a valuable diagnostic marker in distinguishing active TAO from inactive TAO.ConclusionsInflammation- and neuromodulation-related pathways might be closely associated with TAO. Based on the clinical verification, OSM, CSF3R, CXCL6, DPP4, and PRKCG may serve as inflammation- or neuromodulation-related biomarkers for TAO, providing novel insights for the diagnosis and treatment of TAO.

CDK5 Mediates Proinflammatory Effects of Microglia through Activated DRP1 Phosphorylation in Rat Model of Intracerebral Hemorrhage.

Introduction Cyclin-dependent kinase-5 (CDK5) is a key kinase involved in brain development and function and recently found to be involved in neuronal and astroglial apoptosis, neural stem/progenitor cell stemness, mitochondrial fission, and synaptic transmission. But the specific mechanism of CDK5-mediated anti-inflammatory remains unclear in ICH. The aim of the present study was to explore the role of CDK5 in mediating microglia activity through activated DRP1 phosphorylation in a rat ICH model. Methods We measured behavioral change after ICH; detected the expression of CDK5 in the rat brain using immunohistochemistry; and measured the protein levels of CDK5, p35, p25, p-histone H1, and p-DRP1 using Western blot analysis. Coimmunoprecipitation analysis indicated interaction of CDK5 and DRP1. Tumor necrosis factor-α, interleukin- (IL-) 1β, and IL-6 levels were measured using enzyme-linked immunosorbent assay (ELISA). Results After ICH, CDK5 protein level and kinase activity increased. Western blot data showed that CDK5 expression increased from 6 h and peaked at 2 d after ICH (p < 0.05), and the expression of p35 was lowest at 12 h, while the expression of p25 peaked at 2 d after ICH. Besides, p-DRP1 expression change follows with CDK5 kinase activity change. Coimmunoprecipitation showed that interaction between CDK5 and DRP1 certainly exists in microglia. Then, knockdown CDK5 or p35 expression by siRNA reduced the expression level of p-DRP1. ELISA data showed that the protein levels of proinflammatory mediators, such as TNF-α, IL-1β, and IL-6, were decreased by knockdown of CDK5. Conclusion CDK5 may regulate DRP1 by direct phosphorylation in microglia and further induce microglia secreting proinflammation factor.

ITRAQ-Based Proteomic Analysis Reveals Potential Serum Biomarkers for Pediatric Non-Hodgkin's Lymphoma.

Non-Hodgkin’s lymphoma (NHL) is the third most common malignant tumor among children. However, at initial NHL diagnosis, most cases are at an advanced stage because of nonspecific clinical manifestations and currently limited diagnostic methods. This study aimed to screen and verify potential serum biomarkers of pediatric NHL using isobaric tags for relative and absolute quantification (iTRAQ)-based proteomic analysis. Serum protein expression profiles from children with B-NHL (n=20) and T-NHL (n=20) and healthy controls (n=20) were detected by utilizing iTRAQ in combination with two-dimensional liquid chromatography-tandem mass spectrometry (2D LC–MS/MS) and analyzed by applying Ingenuity Pathway Analysis (IPA). The candidate biomarkers S100A8 and LRG1 were further validated by using enzyme-linked immunosorbent assays (ELISAs). Receiver operating characteristic (ROC) analysis based on ELISA data was used to evaluate diagnostic efficacy. In total, 534 proteins were identified twice using iTRAQ combined with 2D LC–MS/MS. Further analysis identified 79 and 73 differentially expressed proteins in B-NHL and T-NHL serum, respectively, compared with control serum according to our defined criteria; 34 proteins were overexpressed and 45 proteins underexpressed in B-NHL, whereas 45 proteins were overexpressed and 28 proteins underexpressed in T-NHL (p < 0.05). IPA demonstrated a variety of signaling pathways, including acute phase response signaling and liver X receptor/retinoid X receptor (LXR/RXR) activation, to be strongly associated with pediatric NHL. S100A8 and LRG1 were elevated in NHL patients compared to normal controls according to ELISA (p < 0.05), which was consistent with iTRAQ results. The areas under the ROC curves of S100A8, LRG1, and the combination of S100A8 and LRG1 were 0.873, 0.898 and 0.970, respectively. Our findings indicate that analysis of the serum proteome using iTRAQ combined with 2D LC–MS/MS is a feasible approach for biomarker discovery. Serum S100A8 and LRG1 are promising candidate biomarkers for pediatric NHL, and these differential proteins illustrate a novel pathogenesis and may be clinically helpful for NHL diagnosis in the future.

Potent Tau Aggregation Inhibitor D-Peptides Selected against Tau-Repeat 2 Using Mirror Image Phage Display.

Alzheimer's disease and other Tauopathies are associated with neurofibrillary tangles composed of Tau protein, as well as toxic Tau oligomers. Therefore, inhibitors of pathological Tau aggregation are potentially useful candidates for future therapies targeting Tauopathies. Two hexapeptides within Tau, designated PHF6* (275‐VQIINK‐280) and PHF6 (306‐VQIVYK‐311), are known to promote Tau aggregation. Recently, the PHF6* segment has been described as the more potent driver of Tau aggregation. We therefore employed mirror‐image phage display with a large peptide library to identify PHF6* fibril binding peptides consisting of D‐enantiomeric amino acids. The suitability of D‐enantiomeric peptides for in vivo applications, which are protease stable and less immunogenic than L‐peptides, has already been demonstrated. The identified D‐enantiomeric peptide MMD3 and its retro‐inverso form, designated MMD3rev, inhibited in vitro fibrillization of the PHF6* peptide, the repeat domain of Tau as well as full‐length Tau. Dynamic light scattering, pelleting assays and atomic force microscopy demonstrated that MMD3 prevents the formation of tau β‐sheet‐rich fibrils by diverting Tau into large amorphous aggregates. NMR data suggest that the D‐enantiomeric peptides bound to Tau monomers with rather low affinity, but ELISA (enzyme‐linked immunosorbent assay) data demonstrated binding to PHF6* and full length Tau fibrils. In addition, molecular insight into the binding mode of MMD3 to PHF6* fibrils were gained by in silico modelling. The identified PHF6*‐targeting peptides were able to penetrate cells. The study establishes PHF6* fibril binding peptides consisting of D‐enantiomeric amino acids as potential molecules for therapeutic and diagnostic applications in AD research.

Seroprevalence of mycoplasmosis in broiler, layer, and native chickens in Giza, Egypt.

We aimed to investigate Mycoplasma infections among chicken flocks (Ross, Lohmann and native) in Giza, Egypt, using serological tests, including the slide plate agglutination (SPA) test, hemagglutination inhibition (HI) test, and enzyme-linked immunosorbent assay (ELISA). The slide plate agglutination examination, a serological test, indicated the prevalence of Mg and Ms infections of 10.9% and 13.2%, respectively. On 91 SPA test positive serum samples for either Mg or Ms, a passive hemagglutination/hemagglutination inhibition (HI) test was performed. The SPA and HI test findings were found to be comparable. On 90 SPA test positive samples, an ELISA was performed using commercial kits for Mg and Ms serodiagnosis. According to the ELISA data, only 83.33% and 18.88% of SPA test positive samples were confirmed as positive for Ms and Mg infections, respectively. The prevalence increased to 84.44% and 77.77%, respectively, when suspected samples were deemed positive.

Optimization of a human milk\u2013directed quantitative sIgA ELISA method substantiated by mass spectrometry

Immunoglobulins are the primary protective products in human milk and are responsible for transferring maternal pathogen memory to the infant, providing protection by binding to recognized pathogens and inhibiting virulence. To better understand potentially protective/anti-infective compounds in human milk, the establishment of human milk–tailored analytical approaches is crucial, as most contemporary analytical methods have been optimized for plasma or serum. One of the most prominent immunoglobulins in human milk is secretory immunoglobulin A (sIgA), which may be relevant for the protection of breastfed infants from harmful pathogens. Advanced sIgA detection methods can help monitor the immune status and development of the mother-infant dyad. We therefore developed an enzyme-linked immunosorbent assay (ELISA) sIgA method for the quantitative analysis of IgA plus secretory component (SC), validated with sIgA standards and substantiated by mass spectrometry (MS)–based proteomics. A very strong correlation was observed between the MS-detected IgA1 and the human milk–specific sIgA ELISA (r = 0.82). Overall, the MS data indicate that the developed human milk sIgA ELISA does not differentiate between sIgA1 and sIgA2 and is, therefore, a reflection of total sIgA. Furthermore, our MS data and the human milk–derived sIgA ELISA data are better correlated than data derived from a standard serum IgA ELISA kit (relative to MS IgA1 r = 0.82 and r = 0.42, respectively). We therefore propose our human milk–specific sIgA ELISA as an ideal quantitative indicator of total sIgA with advantages over current serum IgA ELISA kits.

Nanobody-Dependent Detection of Microcystis aeruginosa by ELISA and Thermal Lens Spectrometry.

Nanobodies against cell surface antigens of toxic cyanobacteria Microcystis aeruginosa were recovered by whole-cell biopanning of a naïve phage display library of nanobodies. Six unique sequences were identified and three sub-cloned and purified as fusion immunoreagents together with either green fluorescent protein or AviTag to be used for diagnostics. The yields of nanobody constructs were in the range of 5-10 mg/l and their specificity and sensitivity was initially evaluated by immunofluorescence and by fluorescent enzyme-linked immunosorbent assay (ELISA) using fluorescent nanobodies. The ELISA data confirmed the nanobody specificity but showed that the saturation of the fluorescence signal already in the presence of few hundreds of cells limited the dynamic range of the method. As an alternative, Avi-tagged nanobodies were used in combination with streptavidin-linked horseradish peroxidase for developing a diagnostic colorimetric cell ELISA, the limit-of-detection of which was 3.2 and 4.5 cells/ml for the two tested cyanobacteria strains, whereas the linear range of the assay was expanded from 10 to 10,000 cells. The fluorescent nanobodies were finally exploited for quantifying cyanobacteria by thermal lens spectrometry (TLS) that enabled to reach a limit-of-detection of 1.2 cells/ml and provided a linear range of measurement between 0 and 10,000 cells. No cross-reactivity with unrelated microalgae was detected and both colorimetric ELISA and TLS provided a linear range of detection of few logs. The data indicate that nanobodies are suitable capture reagents and that both TLS and colorimetric ELISA are reliable to monitor variations of cyanobacteria populations.

Progestogen metabolites for use in pregnancy monitoring of 13-lined ground squirrels (Ictidomys tridecemlineatus).

This research was conducted to discover whether pregnancy prediction is possible in female 13-lined ground squirrels (TLGS; a small hibernating ground squirrel named for their number of stripes). Pregnancy status in this species, we postulated, could be anticipated by generating profiles for individuals via a non-invasive technique known as fecal endocrine hormone profiling. Fecal samples were collected from 13 females thrice weekly for 4 weeks post-hibernation in the breeding season of 2016. Fecal samples were then processed and run through an assay known as an ELISA giving concentrations of hormone metabolites excreted through feces. We then set these samples against time points to develop a profile for each female. We have ascertained that elevated progesterone (potential pregnancy) can be detected by a commercially available assay kit. Understanding hormone patterns in animals gives researchers a better idea of best husbandry practices, including breeding in managed care.

Effects of Exogenous Biliverdin Treatment on Neurobehaviors in Mice.

The neuroprotective effects of heme oxygenase (HO) have been well investigated. The potential effects of exogenous supplementation of biliverdin (BVD), one of the main products catalyzed by HO, on neurobehaviors are still largely unknown. The present study aimed to investigate the effects of BVD treatment on depression, anxiety, and memory in adult mice. Mice were injected with BVD through tail vein daily for a total 5 d, and depression- and anxiety-like behaviors were conducted by using open field test (OFT), novelty suppressed feeding (NSF), forced swimming test (FST) and tail suspension test (TST) since the third day of BVD administration. Novel object recognition (NOR) paradigm was used for memory formation test. After the final test, serum and hippocampal levels of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) of mice were analyzed by enzyme-linked immunosorbent assay (ELISA). The results showed that BVD treatment at low dose (2 mg/kg) induced depression-like behaviors, and high dose (8 mg/kg) BVD injection increased anxiety-like behaviors and impaired memory formation in mice. ELISA data showed that BVD treatment significantly increased hippocampal IL-6 and TNF-α level while only decreasing serum IL-6 level of mice. The present data suggest that exogenous BVD treatment induced depression- and anxiety-like phenotypes, which may be related to inflammatory factors, providing BVD may be a potential target for the prevention of mental disorders.

The antiinflammatory effects of Xuefu Zhuyu decoction on C3H/HeJ mice with alopecia areata

As a traditional and typical prescription of prominently activating blood circulation to remove blood stasis, Xuefu Zhuyu decoction (XZD) consists of 15 kinds of herbal medicine. Clinical investigations have showed that XZD could significantly promote the new hair generation of alopecia areata (AA) patients characterized by Qi stagnation and blood stasis. The purpose of this study was executed to determine whether the mechanisms by which XZD stimulated newborn hair were related to its anti-inflammatory effects. Clinical AA individuals were recruited to confirm the efficies of XZD. High performance liquid chromatography (HPLC) analysis was performed to qualitatively and quantitatively determine the contents of 15 compounds in XZD. Schrodinger molecular docking and in vivo surface plasmon resonance (SPR) techniques were used to evaluate the potential binding properties of compounds to target proteins. C3H/HeJ mice were randomly assigned to groups control, AA, and the XZD administration (6.5, 13.0 and 26.0 g/kg/d). Except for mice in control group, all the mice in the other groups were treated with a 21-day chronic unpredictable mild stress (CUMS) induced AA. Hematoxylin-eosin (H&E) staining was performed to determine the degree of pathological damage to the skin. Enzyme-linked immunosorbent assay (ELISA) was performed to detect levels of interleukin-6 (IL-6), interleukin-1 beta (IL-1β) and tumor necrosis factor alpha (TNF-α) and in serum and skin tissues. Western blot, immunohistochemistry and quantitative reverse transcription-polymerase chain reaction (qRT-PCR) were used to examine the expression levels of IL-6, IL-1β, TNF-α and osteopontin proteins and genes in skin tissues. XZD could visibly promote hair regeneration of AA patients. The potential active ingredients in XZD prescription included at least amygdalin, hydroxysafflor yellow A, kaempferide, ferulic acid, catalpol, verbascoside, β-ecdysone, platycodin D, paeoniflorin, naringin, neohesperidin, liquiritin, glycyrrhizic acid, saikosaponin A and saikosaponin D. The results of molecular docking and SPR analysis showed that verbascoside, liquiritin, kaempferide and amygdalin showed the best potential binding properties with IL-6, IL-1β, TNF-α and osteopontin, respectively. Pathological evaluation showed that compared with the CUMS group, the administration of XZD significantly promoted hair regeneration, evidenced by increased number of skin hair follicles in C3H/HeJ AA mice. Compared with control group, ELISA data showed that the levels of IL-6, IL-1β and TNF-α in serum and skin tissues of CUMS induced AA mice were significantly increased, while XZD administration dramatically restrained the contents of the three pro-inflammatory factors. Western blot, immunohistochemistry, and qRT-PCR results further demonstrated that XZD administration notably down-regulated the protein and gene expression levels of osteopontin, IL-6, IL-1β and TNF-α in comparation with CUMS group. XZD could dramatically ameliorate CUMS-induced AA damage in the skin of C3H/HeJ mice, possibly by suppressing the levels of IL-6, IL-1β, TNF-α and osteopontin.

Novel 2 Marker Sandwich Immunoassay for the Detection of Precursor- and Mature Granulocyte-Derived Exosomes in Peripheral Blood: A Preliminary Case Study

Introduction: In order to assess hematopoietic precursor cells, bone marrow biopsies are routinely conducted, which is painful for the patient and is not applicable for frequent testing. However, precursor, maturating, and matured cells are known to produce exosomes, which are released into peripheral blood. By analyzing these exosomes in plasma, bone marrow condition may be assessed noninvasively. Myeloid precursor cells express different surface markers than when they have matured. It is reasonable to speculate that these markers would be incorporated into exosomes. In this study, we developed a novel sandwich enzyme-linked immunosorbent assay (ELISA) by using a combination of monoclonal antibodies against 2 different leukocyte antigens, to account for the number of exosomes in plasma. Methods In 6 patients undergoing chemotherapy, venous blood was drawn at regular intervals before, during, and after respective chemotherapies was given. Various clones of monoclonal antibodies against CD11b, CD33, CD34, CD35, CD81, and CD117 were obtained, and antibodies were biotinylated by EZ link Sulfo-NHS-LC-Biotin. Anti-brain antibodies were switched with anti-leukocyte antibodies, and exosome activity was trended. Results CD11b+ and CD 117+ plates showed small changes during chemotherapy (within +/- 50% of the initial value), while plasma WBC count showed a dramatic decrease during chemotherapy. In the recovery phase of WBC after chemotherapy, CD11b+ and CD16+showed a greater than 2-fold increase, with the up-trend taking place earlier than its plasma WBC counterparts. CD 117+ CD33+ also showed an up-trend, but was slower than their CD11b+ and CD16+ counterpart. Finally, each exosome value was divided by other markers to calculate the ratio, and compared between pre and post chemotherapy blood. In half of the cases, there was not a difference, versus an almost double premature/mature ratio in post-chemotherapy blood in the other half of patients. Conclusion From data collected from pre-chemotherapy studies, the lack of correlation between ELISA data compared to plasma WBC data, indicates that plasma exosome analysis might not be suitable for the monitoring of acute bone marrow suppression. Additionally, in the recovery phase, surface markers correlation with WBC was present in only some of the markers, indicating that the assay sensitivity is dependent on the marker combinations. Overall, both myeloid precursor- and mature granulocyte-derived exosomes were increased during the recovery from chemotherapy in 3 out of 5 patients, and exosome profiles were different after chemotherapy in 2 out of 5 patients. Disclosures Mitsuhash: NanoSomiX:Current Employment.

Protective anti-prion antibodies in human immunoglobulin repertoires.

Prion immunotherapy may hold great potential, but antibodies against certain PrP epitopes can be neurotoxic. Here, we identified > 6,000 PrP‐binding antibodies in a synthetic human Fab phage display library, 49 of which we characterized in detail. Antibodies directed against the flexible tail of PrP conferred neuroprotection against infectious prions. We then mined published repertoires of circulating B cells from healthy humans and found antibodies similar to the protective phage‐derived antibodies. When expressed recombinantly, these antibodies exhibited anti‐PrP reactivity. Furthermore, we surveyed 48,718 samples from 37,894 hospital patients for the presence of anti‐PrP IgGs and found 21 high‐titer individuals. The clinical files of these individuals did not reveal any enrichment of specific pathologies, suggesting that anti‐PrP autoimmunity is innocuous. The existence of anti‐prion antibodies in unbiased human immunological repertoires suggests that they might clear nascent prions early in life. Combined with the reported lack of such antibodies in carriers of disease‐associated PRNP mutations, this suggests a link to the low incidence of spontaneous prion diseases in human populations.

Niveles de interleucina-6 en el humor acuoso en glaucoma primario de ángulo abierto (GPAA): revisión sistemática y meta-análisis

ObjectiveTo determine the change in aqueous humor interleukin-6 (IL-6) levels among primary open-angle glaucoma (GPAA) patients. MethodsStudies that investigated IL-6 level in the aqueous humor in GPAA patients using the detección methods of enzyme-linked immunosorbent assay (ELISA) y multiplex bead immunoassay were retrieved. A meta-analysis was performed a determine the overall change in IL-6 of GPAA patients compared a controls. ResultsA total of 14 studies were selected. Analysis combining the results of studies using both detección approaches did not show any changes in the level of IL-6 in GPAA (SMD=-0,07, 95%IC -0,73 – 0,59, P=0,83), possibly due a the heterogeneity of ELISA data. Since multiplex bead immunoassay is more sensitive than convenciónal ELISA in detecting antibodies, further isolated analysis of multiplex bead immunoassay results revealed that GPAA patients had a lower level of IL-6 in the aqueous humor compared a controls (SMD=-0,40, 95%IC -0,70 – 0,09, P=0,01). Moreover, a sensitivity test also confirmed that no alteracións of results were observed in all pooled studies y pooled studies from multiplex bead immunoassay, suggesting the stabilities of our synthetic results. ConclusionBecause of its robustness, the pooled data from multiplex bead immunoassay was used a draw a conclusion in this study, showing that the reducción of IL-6 levels in aqueous humor was observed in patients with GPAA. Further studies are still warranted a confirm our findings.

Discovery of Potential Plasma Biomarkers for Tuberculosis in HIV-Infected Patients by Data-Independent Acquisition-Based Quantitative Proteomics.

PurposeTuberculosis (TB) is the leading cause of mortality in individuals infected with human immunodeficiency virus (HIV), yet the methods for detecting Mycobacterium tuberculosis at an early stage remain insensitive or ineffective. This study aimed to discover plasma biomarkers for distinguishing HIV-TB coinfected individuals from HIV individuals without TB (HIV-nonTB).Patients and MethodsA total of 200 Chinese HIV-positive patients were recruited, 100 each for HIV-nonTB group and HIV-TB group. Plasma proteomic profiles were analyzed for 50 patients each in both groups, using data-independent acquisition (DIA)-mass spectrometry-based proteomics. Differently expressed proteins were revealed with ridge regression analysis. Enzyme-linked immunosorbent assay (ELISA) analyses were performed for further validation in other 100 patients.ResultsDIA-mass spectrometry revealed 13 upregulated and 33 downregulated proteins in the HIV-TB group. AMACR (α-methylacyl-CoA racemase), LDHB (L-lactate dehydrogenase B chain), and RAP1B (Ras-related protein Rap-1b) were selected for building a diagnostic model, for which the receiver operation characteristic curve had under areas of 0.99 and 0.89 testing with proteomics data (sensitivity = 92%, specificity = 100%) and ELISA data (sensitivity = 76%, specificity = 92%), respectively.ConclusionThe combination of AMACR, LDHB, and RAP1B proteins may serve as a potential marker of TB in HIV-infected patients.

Seroprevalence in Bats and Detection of Borrelia burgdorferi in Bat Ectoparasites.

The role of bats in the enzootic cycle of Lyme disease and relapsing fever-causing bacteria is a matter of speculation. In Canada, Borrelia burgdorferi sensu stricto (ss) is the genospecies that is responsible for most cases of Lyme disease in humans. In this study, we determined if big brown bats, Eptesicus fuscus, have been exposed to spirochetes from the genus Borrelia. We collected serum from 31 bats and tested them for the presence of anti-Borrelia burgdorferi antibodies using a commercial enzyme-linked immunosorbent assay (ELISA). We detected cross-reactive antibodies to Borrelia spp. in 14 of 31 bats. We confirmed the ELISA data using a commercial immunoblot assay. Pooled sera from ELISA-positive bats also cross-reacted with Borrelia antigens coated on the immunoblot strips, whereas pooled sera from ELISA-negative bats did not bind to Borrelia spp. antigens. Furthermore, to identify if bat ectoparasites, such as mites, can carry Borrelia spp., we analyzed DNA from 142 bat ectoparasites that were collected between 2003 and 2019. We detected DNA for the Borrelia burgdorferi flaB gene in one bat mite, Spinturnix americanus. The low detection rate of Borrelia burgdorferi DNA in bat ectoparasites suggests that bats are not reservoirs of this bacterium. Data from this study also raises intriguing questions about Borrelia infections in bats, including the role of humoral immunity and the ability of bats to be infected with Borrelia burgdorferi. This study can lead to more sampling efforts and controlled laboratory studies to identify if bats can be infected with Borrelia burgdorferi and the role of bat ectoparasites, such as S. americanus, in the transmission of this spirochete. Furthermore, we outlined reagents that can be used to adapt ELISA kits and immunoblot strips for use with bat sera.

Effect of linking arm hydrophilic/hydrophobic nature, length and end-group on the conformation and the RGD accessibility of surface-immobilized fibronectin.

In order to stimulate the cellular response to implant materials, extracellular matrix (ECM) proteins, such as collagen and fibronectin (FN), are immobilized on the implant surface. Amongst all ECM proteins used for biomimetic materials for medical applications, FN is one of the most investigated proteins thanks to its ability to promote cell adhesion and its contribution to important physiological processes. However, its conformation and hence its bioactivity strongly depend on the hydrophilic/hydrophobic nature of the surface as well as on immobilization strategies. This work investigates the effect of these two parameters, as well as the effect of the crosslinker length. FN was grafted onto silicon wafers using eights different linking arms presenting different lengths, hydrophilic/hydrophobic characters and binding sites. The protein was linked through either its amino groups (lysine amino acids) or sulfhydryl functionalities (cysteine amino acids). The grafting of each crosslinker and subsequent FN conjugation onto the surfaces was evidenced by X-ray photoelectron spectroscopy, while the surface hydrophilicity was determined by contact angle measurements. Moreover, atomic force microscopy images revealed that the conformation of surface conjugated FN only depends on the hydrophilicity of the linking arm. The FN conformation was also probed by enzyme-linked immunosorbent assays (ELISA). ELISA data demonstrated that all of the three investigated parameters linking arm parameter (length, hydrophobic/hydrophilic character, and terminal end-group) somewhat influence the RGD accessibility.

Changes of B cell subsets in central pathological process of autoimmune encephalomyelitis in mice

BackgroundMultiple sclerosis is a demyelinating and autoimmune disease and its immune response is not fully elucidated. This study was conducted to examine the pathological changes and B cell subsets in experimental autoimmune encephalomyelitis (EAE) mice, and analyze the expression of triosephosphate isomerase (TPI) and GADPH to define the role of B cell subsets in the disease.ResultsFemale C57BL/6 mice were randomly divided into EAE group (n = 18) and control (n = 18). During the experiments, the weight and nerve function scores were determined. The proportions of B cell subsets in the peripheral blood were measured by flow cytometry. Seven, 18 and 30 days after immunization, the brain and spinal cord tissues were examined for the infiltration of inflammatory cells using hematoxylin-eosin (HE) HE staining and the demyelination using Luxol fast blue staining. The expression of B cell-related proteins was detected immunohistochemistrially and the expression of antigenic TPI and GADPH was analyzed using enzyme-linked immunosorbent assay (ELISA). HE staining showed that mice had more severe EAE 18 d than 7 d after modelling, while the symptoms were significantly relieved at 30 d. The results were consistent with the weight measurements and neural function scores. Immunohistochemistry studies showed that B cells aggregated in the spinal cord, but not much in the brain. Flow cytometry studies showed that there were more B cells in control than in EAE models from day 7 and the difference was narrowed at day 30. The level of plasma cells increased continuously, reached the top at day 21 and obviously declined at day 30. On other hand, the numbers of memory B cells increased gradually over the experimental period. The numbers of plasma and memory B cells were similar between the control and EAE mice. ELISA data revealed that the brain contents of TPI and GAPDH were higher in EAE mice than in control at day 7, while at day 18, the levels were reversed.ConclusionsIn the central pathological process of EAE mice, B cells exert role through the mechanism other than producing antibodies and the levels of brain TPI and GADPH are related to the severity of autoimmune induced-damage.