Journal of immunoassay & immunochemistry最新文献

Rapid diagnosis of patients with severe Dengue infection can be useful for the efficient clinical management of cases caused by the Dengue virus. Lateral Flow Immunoassay (LFIA) have been broadly used for rapid Dengue diagnosis, because of their quick readouts with the human eye, simplicity of use, and affordability. Despite the availability of several commercial Dengue point-of-care assays, none has shown to be successful in discriminating between severe and nonsevere forms of Dengue infection. In the current study, for the first time, a novel lectin-based point-of-care assay for the early detection of patients with severe Dengue infection with gold-adorned sheets as detection labels is being reported. In this assay, Dengue severity was diagnosed by detecting the glycosylation profile of vitronectin, a known Dengue severity marker. Two lectins were employed namely DSA (Datura stramonium) and MAA (Maackia amurensis) that can recognize specific glycans like galactose Gal-(1-4) GlcNAc and sialic acid in an (α2-3) linkage, which displayed high sensitivity and high specificity, i.e. 90% and 85% for DSA and 90.91% and 95% for MAA. The new assay has a detection limit of 5 µg µl^-1 and enables the quick (30 min) and sensitive detection of severe Dengue cases. The reported point-of-care immunoassay exhibits considerable promise for early identification of patients with Dengue severity.

Gastric carcinoma (GC) is one of the most prevalent cancers worldwide and the fourth leading cause of cancer-related death. Studying the molecular profile of GC is essential for developing targeted therapies. β-catenin, Tenascin, and Fascin expression are among the molecular abnormalities that are claimed to cause GC progression and chemoresistance. Therefore, they could be used as potential therapeutic targets. This study aimed to evaluate β-catenin, Tenascin, and Fascin expression and their possible roles as prognostic and predictive biomarkers in GC using immunohistochemistry. This retrospective study included 84 GC cases. Tissue microarrays were constructed, followed by β-catenin, Tenascin, and Fascin immunostaining. Their expression was assessed and compared with clinicopathological parameters and survival data. The study results revealed that β-catenin nucleocytoplasmic expression, positive Tenascin, and Fascin expressions were detected in 86.9%, 70%, and 59.5% of cases, respectively. Their expression was significantly associated with poor prognostic parameters, such as deeper tumor invasion, lymph node metastasis, advanced pathological stage, vascular invasion, positive omental nodules, poor response to chemotherapy, and short overall survival. Hence, nucleocytoplasmic β-catenin expression together with Tenascin and Fascin positivity can be potential prognostic and predictive markers, and they can be used as therapeutic targets for GC.

Studying the expression of hematopoietic stem cell markers from different sources might be useful in understanding stem cell biology in different niche conditions. The study aimed to assess the difference in cell surface markers (CD44, CD90, CD96) on hematopoietic stem cells in three different niche conditions; umbilical cord blood (UCB), normal bone marrow (NBM) and bone marrow samples from idiopathic (immune) thrombocytopenic purpura (IBM). This study was conducted on 300 cases divided into three study groups; 100 umbilical cord blood units collected from mothers undergoing cesarian section in gynecology and obstetrics department, 100 bone marrow samples from idiopathic (immune) thrombocytopenic purpura patients collected from university children hospital and 100 normal bone marrow samples with no evidence of disease in bone marrow tissue. CD44 was significantly elevated in UCB and NBM groups compared to IBM group (<0.001). There was also a significant elevation of CD90 and CD96 in IBM group compared to NBM group and UCB (<0.001). CD90 and CD96 play a role in the pathogenesis of ITP disorder and could be applied as a targeted therapy to improve the outcome of this disease.

Immunoassay tests are used in clinical and forensic toxicology laboratories to determine illicit drug use in biological samples. Therefore, this study aims to optimize the cutoff concentrations of DOA I Plus in the blood and compare the LC-MS/MS results. 680 authentic forensic whole blood specimens with Randox Evidence DOA I Plus array were screened for drug of abuse and confirmed by LC-MS/MS. Regarding the manufacturer recommended threshold values, 139 out of 680 authentic blood samples were positive for one or more analytes, while 541 were negative. Nearly all of the 139 positive blood samples confirmed by LC-MS/MS were true positive for one or more analytes, while 522 of the 541 negative blood samples were true negative. The overall sensitivity and the specificity were 87.8% and 99.6%, respectively. THC was considered in detail, and a receiver operator characteristic curve analysis was performed to determine the optimum cutoff for THC, as it accounts for 78% of all positive results according to the manufacturer's recommended thresholds. The optimal threshold value for THC was determined at a concentration of 23 ng/mL, while these values for other parameters were defined as recommended by the manufacturer.

Several diagnostic measures have been employed to precisely detect the SARS-CoV-2 viral infection using viral antigens, nucleic acids, and other serological approaches. The sensitivity and specificity of the serological tests remain a challenging need. Here, we describe the detection of human anti-SARS-CoV-2 IgG and IgM antibodies qualitatively through two optimized in-house ELISA and lateral flow immunoassay. Both approaches are based on the prokaryotic expression of 50 kDa SARS-CoV-2 recombinant nucleocapsid protein. This SARS-CoV-2rN-6×His was used either to coat ELISA plates or to be conjugated to gold nanoparticles followed by colorimetric detection of bound human IgG or IgM. In the LFA, we show the optimization of nanoparticle size, protein-binding capacity, membrane treatment, and finally testing the potential capacity of using either the optimized ELISA or LFA in detecting antibodies raised against viral infection. Assessment of both methods was carried out using human sera-positive and negative SARS-CoV-2 antibodies. The ELISA and LFA tests showed 86%, 96.5% sensitivity, 92%, 93.75% specificity, 97%, 98.2% PPV, and 64%, 88.2% NPV, respectively. In conclusion, both approaches were able to successfully detect human antibodies against SARS-CoV-2 nucleocapsid protein. The importance of both protocols cannot be overstated in the detection and diagnosis of viral infections, especially in developing countries.

Tetanus is an acute and often fatal infectious disease caused by Clostridium tetani. Tetanus toxin (TT) is responsible for spastic paralysis observed in tetanus. Anti-tetanus antibodies obtained from horses and humans are the most antitoxins used for tetanus treatment, although some clinical side effects and disadvantages have been reported in their application. The aim of this study is the production of anti-TT IgY and evaluation of its protective effects in a mouse model. Anti-TT IgY was purified from the egg yolk using PEG6000 precipitation and water dilution methods, and its purity was verified by SDS-PAGE. Finally, the potency of purified anti-TT IgY in neutralizing the lethal effects of TT was studied in vivo using a mouse model. PEG6000 precipitation method had better results. Animal studies showed that the purified IgY neutralized the toxic effects of 100 MLD of TT and multiple intravenous-dose injections of anti-TT IgY also had a continuous effect of TT neutralization. The purified anti-TT IgY was effective in neutralizing the lethal activity of TT in a mouse model. Our results suggested that IgY could be an alternative therapeutic source for the management of tetanus in the future.Abbreviations Anti-TT, Anti-tetanus toxin; ELISA, Enzyme-linked immunosorbent assay; IgY, Immunoglobulin Y; MLD, Minimum lethal dose; PBS, Phosphate buffer solution; PEG, Polyethylene glycol; SDS-PAGE, Sodium dodecyl sulfate polyacrylamide gel electrophoresis; TIG, Tetanus immune globulin; TT, Tetanus toxin; WD, Water dilution; RT, Room temperature.

Probiotics positively influence age-related macular degeneration (ARMD) given their propensity to attenuate oxidative and inflammatory stress. We addressed the impact of probiotics on metabolic profiles, clinical indices, inflammatory and oxidative stress parameters in ARMD patients. We performed a randomized, double-blind, placebo-controlled trial analyzing 57 subjects with ARMD aged between 50 and 85 years. Subjects were randomized into two groups, and received daily for 8 weeks either probiotic capsule or placebo. Fasting blood samples were obtained at baseline and after the 8-week intervention for the determination of metabolic profiles and oxidative stress biomarkers. After the 8-week intervention, compared with the placebo, probiotic supplementation significantly increased means HDL-cholesterol (Probiotic group: +3.86±4.42 vs. Placebo group: -0.55±4.93 mg/dL, P = .001), plasma total antioxidant capacity (TAC) (Probiotic group: +77.43±168.30 vs. Placebo group: -23.12±169.22 mmol/L, P = .02) and significantly decreased malondialdehyde (MDA) levels (Probiotic group: -0.18±0.46 vs. Placebo group: +0.18±0.25 µmol/L, P = .001). There was no significant effect of probiotic administration on other metabolic profiles and clinical symptoms. Overall, an eight-week probiotic administration among ARMD patients had beneficial effects on TAC, MDA and HDL-cholesterol levels; however, it did not affect clinical signs and other metabolic profiles.

Changes in the immune system participate in the pathogenesis and development of infectious diseases. Previous studies have indicated immune dysregulation in patients suffering from COVID-19 and mucormycosis. Therefore, this study investigated whether interleukin-27 (IL-27) and interleukin-32 (IL-32) levels may participate in the development and outcome of COVID-19 associated mucormycosis (CAM). The blood samples were obtained from 79 patients suffering from COVID-19 and mucormycosis and 25 healthy subjects. The serum samples were isolated from the whole blood and frequencies of some immune cells were measured by a cell counter. The levels of IL-27 and IL-32 were assessed by enzyme-linked immunosorbent assay. IL-27 and IL-32 levels were significantly lower in patients with COVID-19 and mucormycosis than healthy subjects (P < .05), although there was no significant difference in IL-27 between patients with COVID-19 and CAM. IL-27 level was significantly higher in severe COVID-19 survivors than dead cases (P < .01). Patients with CAM had significant increases in NLR compared to COVID-19 patients and healthy individuals (P < .0001-0.01). NLR was significantly associated with COVID-19 outcome (P < .05). Severe COVID-19 survivors had a significant reduction in NLR compared to non-survivors (P < .05). Changes in IL-27 and IL-32 levels may contribute to the pathogenesis of CAM. IL-27 may relate to the pathogenesis and outcomes of mucormycosis in COVID-19 patients.