Search

When abrin-a was combined with several polyclonal antibodies (PAb), the detection limit could be increased. In this way, a monoclonal antibody (capture) and polyclonal antibody (detection) sandwich enzyme-linked immunosorbent assay (ELISA) and a colloidal gold-PAb conjugate-based immunochromatographic assay for detection of abrin-a were developed. The ELISA had a detection limit of 3.9 ng/mL for abrin-a in standard solution and 7.8 ng/mL in soybean milk, and was more sensitive than polyclonal antibody (capture) and monoclonal antibody (detection) ELISA, which had a detection limit of 15.6 ng/mL. The test strip had a detection range of 50 to 500 ng/mL for abrin-a and a detection limit in standard solution or soybean milk samples of 50 ng/mL. However, the test strip had a reduced detection capability compared with a colloidal gold-monoclonal antibody conjugate-based immunochromatographic assay test strip, which had a lower detection limit of 10 ng/mL. The developed ELISAs and test strip show the specificity towards abrin-a and have no cross-reactivity towards abrin-b, -c, -d, ricin, or the agglutinins from either castor beans or rosary peas.

Progesterone (P4) is a steroid gonadal hormone that is mainly produced from the corpus luteum and placenta and has various biological functions, especially reproductive regulation. It is important to establish a specific and sensitive P4 enzyme-linked immunosorbent assay (ELISA) for the study of ovary activity and reproductive disorders. Therefore, we prepared a monoclonal antibody (MAb) in a completed antigen (11α-OH-P4-HS-OVA). Based on the MAb and our previously prepared completed antigen, a highly specific and sensitive ELISA was developed. In the present study, a competitive ELISA for the determination of P4 was described in dairy cow milk. It was found that P4 concentration in milk samples from five pregnant cows was significantly higher than that from five estrus cows. The diagnosis rate for pregnancy and non-pregnancy in 54 dairy cows were 93.3% and 95.8%, respectively, at 19 to 23 days after pregnancy by detecting milk P4 concentration. In summary, the developed ELISA is a potential tool for P4 research and offers an alternative, simple, rapid technique for detecting P4, especially in future large clinical investigations on pregnancy identification and reproductive disorders in dairy farms in China.

Purpose: This study aims to evaluate the value of tissue inhibitors of MMPs-2 (TIMP-2) to indicate 5-Fluorouracil (5-Fu) resistance status in colorectal cancer. Methods: The 5-Fu resistance of colorectal cancer cell lines was detected using Cell-Counting Kit-8 (CCK-8) and calculated using IC50. Enzyme-linked immunosorbent assay (ELISA) and real time-quantitative polymerase chain reaction (RT-qPCR) were used to detect TIMP-2 expression level in the culture supernatant and serum. Twenty-two colorectal cancer patients' TIMP-2 levels and clinical characteristics were analyzed before and after chemotherapy. Additionally, the patient-derived xenograft (PDX) model of 5-Fu resistance was used to evaluate the feasibility of TIMP-2 as a predictive biomarker of 5-Fu resistance. Results: Our experimental results display that TIMP-2 expression is elevated in colorectal cancer drug-resistant cell lines, and its expression level is closely related to 5-Fu resistance. Moreover, TIMP-2 in colorectal cancer patient serum undergoing 5-Fu-based chemotherapy could indicate their drug resistance status, and its efficacy is higher than CEA and CA19-9. Finally, PDX model animal experiments reveal that TIMP-2 can detect 5-Fu resistance in colorectal cancer earlier than tumor volume. Conclusion: TIMP-2 is a good indicator of 5-Fu resistance in colorectal cancer. Monitoring the serum TIMP-2 level can help the clinician identify 5-Fu resistance in colorectal cancer patients earlier during chemotherapy. [ABSTRACT FROM AUTHOR]

Background: Periodontitis is a chronic infection initiated by oral bacterial and their virulence factors, yet the severity of periodontitis is largely determined by the dysregulated host immuno-inflammatory response. Baicalein is a flavonoid extracted from Scutellaria baicalensis with promising anti-inflammatory properties. This study aims to clarify the anti-inflammatory and osteogenic effects of baicalein in periodontal ligament cells (PDLCs) treated with lipopolysaccharides (LPS). Methods: Human PDLCs were incubated with baicalein (0–100 μM) for 2 h prior to LPS challenge for 24 h. MTT analysis was adopted to assess the cytoxicity of baicalein. The mRNA and protein expression of inflammatory and osteogenic markers were measured by real-time polymerase chain reaction (PCR), western blot and enzyme-linked immunosorbent assay (ELISA) as appropriate. Alkaline phosphatase (ALP) and Alizarin red S (ARS) staining were performed to evaluate the osteogenic differentiation of PDLCs. The expression of Wnt/β-catenin and mitogen-activated protein kinase (MAPK) signaling related proteins was assessed by western blot. Results: MTT results showed that baicalein up to 100 μM had no cytotoxicity on PDLCs. Baicalein significantly attenuated the inflammatory factors induced by LPS, including interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), matrix metalloprotein-1 (MMP-1), MMP-2 and monocyte chemoattractant protein 1 (MCP-1) at both mRNA and protein level. Moreover, MAPK signaling (ERK, JNK and p38) was significantly inhibited by baicalein, which may account for the mitigated inflammatory response. Next, we found that baicalein effectively restored the osteogenic differentiation of LPS-treated PDLCs, as shown by the increased ALP and ARS staining. Accordingly, the protein and gene expression of osteogenic markers, namely runt-related transcription factor 2 (RUNX2), collagen-I, and osterix were markedly upregulated. Importantly, baicalein could function as the Wnt/β-catenin signaling activator, which may lead to the increased osteoblastic differentiation of PDLCs. Conclusions: With the limitation of the study, we provide in vitro evidence that baicalein ameliorates inflammatory response and restores osteogenesis in PDLCs challenged with LPS, indicating its potential use as the host response modulator for the management of periodontitis. [ABSTRACT FROM AUTHOR]