Isolation and characterization of a novel human scFv inhibiting EGFR vIII expressing cancers

Phage Display as a Medium for Target Therapy Based Drug Discovery, Review and Update

Phage libraries are now amongst the most prominent approaches for the identification of high-affinity antibodies/peptides from billions of displayed phages in a specific library through the biopanning process. Due to its ability to discover potential therapeutic candidates that bind specifically to targets, phage display has gained considerable attention in targeted therapy. Using this approach, peptides with high-affinity and specificity can be identified for potential therapeutic or diagnostic use. Furthermore, phage libraries can be used to rapidly screen and identify novel antibodies to develop immunotherapeutics. The Food and Drug Administration (FDA) has approved several phage display-derived peptides and antibodies for the treatment of different diseases. In the current review, we provided a comprehensive insight into the role of phage display-derived peptides and antibodies in the treatment of different diseases including cancers, infectious diseases and neurological disorders. We also explored the applications of phage display in targeted drug delivery, gene therapy, and CAR T-cell.

Targeting Design of Human Anti-idiotypic Genetically Engineered Antibody for Simulating the Structure and Insecticidal Function of Bt Cry1C Toxin

The β-type anti-Id (Ab2β) is considered to have potential for simulating the structure and function of the antigen. In this study, a β-type anti-Id (3A7 anti-I-GEAb) of the Cry1C toxin was captured from a GEAb library. Subsequently, a higher activity of mutant (3A7 mutant 8) was obtained from the mutagenesis library based on 3A7 anti-I-GEAb. The LD50 values of 3A7 anti-I-GEAb and 3A7 mutant 8 reach up to 38.9% and 46.8% of Cry1C toxin for P. xylostella and reach up to 32.9% and 37.4% of Cry1C toxin for H. armigera. Additionally, an IC-ELISA was established based on 3A7 mutant 8 (as the coated "antigen"), with an LOD value of 0.35 ng/mL, exhibiting good accuracy and stability for detecting Cry1C toxin in spiked samples. The present β-type anti-I-GEAb not only exhibits insecticidal activity similar to Cry1C toxin, offering potential for environmentally friendly pest management, but it can also replace the Cry1C toxin structure to establish a highly sensitive and specific IC-ELISA for monitoring Cry1C toxin.

Advancements in ovarian cancer immunodiagnostics and therapeutics via phage display technology

Ovarian cancer, ranking as the seventh most prevalent malignancy among women globally, faces significant challenges in diagnosis and therapeutic intervention. The difficulties in early detection are amplified by the limitations and inefficacies inherent in current screening methodologies, highlighting a pressing need for more efficacious diagnostic and treatment strategies. Phage display technology emerges as a pivotal innovation in this context, utilizing extensive phage-peptide libraries to identify ligands with specificity for cancer cell markers, thus enabling precision-targeted therapeutic strategies. This technology promises a paradigm shift in ovarian cancer management, concentrating on targeted drug delivery systems to improve treatment accuracy and efficacy while minimizing adverse effects. Through a meticulous review, this paper evaluates the revolutionary potential of phage display in enhancing ovarian cancer therapy, representing a significant advancement in combating this challenging disease. Phage display technology is heralded as an essential instrument for developing effective immunodiagnostic and therapeutic approaches in ovarian cancer, facilitating early detection, precision-targeted medication, and the implementation of customized treatment plans.

AZD3759 inhibits glioma through the blockade of the epidermal growth factor receptor and Janus kinase pathways

Glioma is an intracranial malignant tumor with high morbidity in China. Limited efficacy has been achieved in the treatment of glioma through the application of epidermal growth factor receptor (EGFR) inhibitors, which is reported to be related to the poor permeability of the brain–blood barrier (BBB) to EGFR inhibitors. AZD3759 and osimertinib are both BBB-penetrating EGFR inhibitors. The present study aimed to investigate the inhibitory effects of AZD3759 and osimertinib on glioma and compare their efficacy and the underlying mechanisms. C6 and U87 cells were incubated with different concentrations of AZD3759 (1, 2, and 4 μM) and 4 μM osimertinib, respectively. C6-LUC xenograft animals were administered different doses of AZD3759 (15, 30, and 60 mg/kg) and 60 mg/kg osimertinib. We found that proliferation was significantly suppressed and that apoptosis and cell cycle arrest were dramatically induced in both C6 and U87 cells by AZD3759 in a dose-dependent manner. Compared to AZD3759, osimertinib had inferior effects on proliferation, apoptosis, and cell cycle. In vivo experiments verified that the anti-tumor efficacy of AZD3759 against C6 xenograft tumors was dose dependent and superior to that of osimertinib. The inhibitory effects of AZD3759 on the Janus kinase (JAK)/STAT pathway were observed in both glioma cells and tumor tissues, which were more significant than those of osimertinib. In conclusion, AZD3759 may inhibit the progression of glioma via a synergistic blockade of the EGFR and JAK/STAT signaling pathways.

Anti-cancer Immunotoxins, Challenges, and Approaches

The development of recombinant immunotoxins (RITs) as a novel therapeutic strategy has made a revolution in the treatment of cancer. RITs result from the fusion of antibodies to toxin proteins for targeting and eliminating cancerous cells by inhibiting protein synthesis. Despite indisputable outcomes of RITs regarding inhibition of multiple cancer types, high immunogenicity has been known as the main obstacle in the clinical use of RITs. Various strategies have been proposed to overcome these limitations, including immunosuppressive therapy, humanization of the antibody fragment moiety, generation of immunotoxins originated from endogenous human cytotoxic enzymes, and modification of the toxin moiety to escape the immune system. This paper is devoted to review recent advances in the design of immunotoxins with lower immunogenicity.

Isolation and characterizations of a novel recombinant scFv antibody against exotoxin A of Pseudomonas aeruginosa

BACKGROUND

Pseudomonas aeruginosa is the leading cause of nosocomial infections, especially in people with a compromised immune system. Targeting virulence factors by neutralizing antibodies is a novel paradigm for the treatment of antibiotic-resistant pseudomonas infections. In this respect, exotoxin A is one of the most potent virulence factors in P. aeruginosa. The present study was carried out to identify a novel human scFv antibody against the P. aeruginosa exotoxin A domain I (ExoA-DI) from a human scFv phage library.

METHODS

The recombinant ExoA-DI of P. aeruginosa was expressed in E. coli, purified by Ni-NTA column, and used for screening of human antibody phage library. A novel screening procedure was conducted to prevent the elimination of rare specific clones. The phage clone with high reactivity was evaluated by ELISA and western blot.

RESULTS

Based on the results of polyclonal phage ELISA, the fifth round of biopanning leads to the isolation of several ExoA-DI reactive clones. One positive clone with high affinity was selected by monoclonal phage ELISA and used for antibody expression. The purified scFv showed high reactivity with the recombinant domain I and full-length native exotoxin A.

CONCLUSIONS

The purified anti-exotoxin A scFv displayed high specificity against exotoxin A. The human scFv identified in this study could be the groundwork for developing a novel therapeutic agent to control P. aeruginosa infections.

Microcystin-LR heterologous genetically engineered antibody recombinant and its binding activity improvement and application in immunoassay

Microcystin-LR (MC-LR) is a high-toxic biohazard that pollutes ecological environment and agroproducts. In this study, a newly recombined genetically engineered antibody (AV_HH-MV_H) with higher thermal stability and binding activity was designed by chain shuffling and based on our previously obtained anti-MC-LR scFv and nanobody. Based on AV_HH-MV_H template, a capacity of 8.99 × 10⁵ CFU/mL of phage display AV_HH-MV_H mutagenesis library was constructed by site-directed mutagenesis in MV_H-CDR3 region, and then used for ultrasensitive mutants screening. Afterwards, a total of five positive AV_HH-MV_H mutants were isolated from the mutagenesis library, and their binding activity was higher than AV_HH-MV_H for MC-LR. The AV_HH-MV_H mutant 3 was cloned into pET-25b vector for soluble expression, and the concentration of target protein expressed in culture system was 43.5 mg/L. An indirect competitive enzyme-linked immunosorbent assay (IC-ELISA) was established based on purified AV_HH-MV_H mutant 3 protein, and it showed ultrasensitive binding activity for MC-LR with the detection limit of 0.0075 μg/L, which was far below the maximum residue limit standard of 1.0 μg/L in drinking water proposed by World Health Organization. The established IC-ELISA shows good accuracy, repeatability, stability and applicability for MC-LR spiked samples, and it is promising for MC-LR ultrasensitive monitoring.

Micronutrient therapy and effective immune response: a promising approach for management of COVID-19

The escalating prevalence of coronavirus disease 2019 (COVID-19) worldwide, with an increased rate of morbidity and mortality, highlights an urgent need to develop more effective therapeutic interventions. Despite the authorized treatment against COVID-19 by the European Union (EU), the safety and effectiveness of this therapeutic strategy for a wide variety of patients have remained a significant challenge. In this respect, micronutrients such as vitamins and minerals, as essential factors, can be considered for improving the function of the immune system and accelerating the treatment procedure. Dietary supplements can attenuate vascular and inflammatory manifestations related to infectious diseases in large part due to their anti-inflammatory and antioxidant properties. Recently, it has been revealed that poor nutritional status may be one of the notable risk factors in severe COVID-19 infections. In the current review, we focus on the micronutrient therapy of COVID-19 patients and provide a comprehensive insight into the essential vitamins/minerals and their role in controlling the severity of the COVID-19 infection. We also discuss the recent advancements, challenges, negative and positive outcomes in relevance to this approach.

High sensitive single chain variable fragment screening from a microcystin-LR immunized mouse phage antibody library and its application in immunoassay

Microcystin-LR (MC-LR) is one of common high-toxic biotoxins produced by cyanobacteria in waterbody. A high sensitive and convenient detection method is necessary for monitoring for MC-LR. To establish a high sensitive indirect competitive enzyme-linked immunosorbent assay (IC-ELISA) based on single chain variable fragment (scFv) for detecting MC-LR, 16 positive anti-MC-LR phage scFv particles were screened out from a MC-LR-immunized mouse phage scFv library, which was successfully constructed with the capacity of 8.67 × 10⁷ CFU/mL. The most positive anti-MC-LR phage scFv (MscFv7) was successfully expressed in Escherichia coli (E.coli) HB2151. The molecular weight (M.W.) of expressed protein was about 30 kDa, and the concentration of purified protein was 512.6 μg/mL analyzed by SDS-PAGE and protein quantitative respectively. The IC-ELISA based on MscFv7-scFv for MC-LR shows a half-maximum inhibition (IC₅₀) of 0.471 μg/L and a limit of detection (LOD) of 0.044 μg/L, which is below the maximum residue limit standard (MRLs) of 1.0 μg/L in drinking water. The MscFv7-scFv has a strong cross-recognition for MC-RR and MC-YR with cross-reactivity (CRs) of 93.1% and 85.9%, respectively, but weak for MC-LW with that of 9.7%, even non-recognition for MC-WR, MC-LF and MC-LY. The recovery rates of IC-ELISA to detect MC-LR spiked in different cleanliness of water samples were 81.2-106.3% with CVs of 2.62-10.22% at intra-assay and inter-assay. The results showed that we obtained a high sensitive anti-MC-LR scFv, and the established IC-ELISA based on MscFv7-scFv should be promising for ultrasensitive monitoring MC-LR, MC-RR and MC-YR in water samples.

Emotional exhaustion-induced latent autoimmune diabetes in adults in a young lady: A CARE-compliant case report

RATIONALE

Latent autoimmune diabetes in adults (LADA) refers to an autoimmune disorder characterized with detectable islets antibodies in the early diagnosis and increased autoimmune beta-cell failure progression. Notably, this kind of diabetes seems to be confused with other phenotypic diabetes.

PATIENT CONCERNS

A young woman suffered an emotional exhaustion-induced LADA, showing asthenia, polydipsia, polyuria, and visible weight loss. The patient emotionally ended a 14-year romantic relationship, leading to the emotional flooding.

DIAGNOSES

The data from physical examination and laboratory tests exhibited as follows: glutamic acid decarboxylase antibody (GADA) = 63.83 U/mL, the fasting blood glucose (FBG) = 13.3 mmol/L, and glycated haemoglobin (HbA1c) = 10.9%. According to levels of GADA, the patient was diagnosed as LADA.

INTERVENTIONS

The patient was clinically treated with insulin for 3-month. Then, running, diet-control, and emotional treatment were combined, such as the patient started a new relationship.

OUTCOMES

An emotional recovery initiated from a new romantic relationship and a baby, showing normal levels of GAD65 (27.007 IU/mL) and FBG (5.46) mmol/L.

LESSONS

The emotional exhaustion might play a significant role in induction of LADA. It is important that individuals should maintain optimism, cheer, and a positive attitude.

Serum TNF-α concentrations in type 2 diabetes mellitus patients and diabetic nephropathy patients: A systematic review and meta-analysis

OBJECTIVES

The aim of this study was to investigate whether the concentrations of serum tumor necrosis factor-α (TNF-α), a pro-inflammatory cytokine, increased in type 2 diabetes mellitus (T2DM) and type 2 diabetic nephropathy (T2DN) patients.

METHODS

The four databases (PubMed, CNKI, WanFang and Chinese-Cqvip) were searched from Jan 1, 1999 to October 1, 2016 for all clinical case-control studies about the serum TNF-α concentrations in T2DM and T2DN patients. All relevant data were extracted from published reports. The meta-analysis was performed to compare the changes of serum TNF-α concentrations of T2DN and T2DM patients in Eastern and Western with healthy controls. We further evaluated concentrations of serum TNF-α in T2DN patients with mincroalbuminuria or macroalbuminuria. Random-effects models were adopted to assess the pooling data among various variations.

RESULTS

In total of 6 studies (744 patients and 277 healthy controls) were included in this study. Compared with healthy controls (both p<0.01), the groups of different albuminuria levels and ethnicities both showed that the serum TNF-α levels were significantly elevated in T2DN patients as well as in eastern T2DN patients (p=0.001), but not significant changed in western T2DN patients (p=0.081). The results were stable through sensitivity analysis and no significant publications bias existed in this meta-analysis.

CONCLUSIONS

Serum TNF-α concentrations are obviously increased in T2DN and T2DM patients, but higher in T2DN patients, suggesting an elevated inflammatory burden in T2DN patients.