Development and characterization of a camelid single‐domain antibody directed to human CD22 biomarker

Abstract

CD22 is a B-cell-specific trans-membrane glycoprotein, which is found on the surface of the most B cells and modulates their function, survival, and apoptosis. Recently, targeting this cell surface biomarker in B-cell malignancies and disorders has attracted a lot of attention. The variable domain of camelid single-chain antibodies (VHH, nanobody) is a form of antibodies with novel properties including small size (15-17 kDa), thermal and chemical stability, high affinity and homology to human antibody sequences. In this study, a novel anti-CD22-specific VHH (Nb) has been developed and characterized by the screening of an immunized phage display library and its binding to CD22 B cells is evaluated. Produced anti-CD22 VHH had a single protein band about 17 kDa of molecular size in Western blotting and its binding affinity was approximately 9 × 10 M. Also, this product had high specificity and it was able to recognize the natural CD22 antigen in CD22+ cell lysate as well as on the cell surface (93%). This anti-CD22 VHH with both high affinity and specificity recognizes CD22 antigen well and can be used in diagnosis and treatment of B cell disorders and malignancies.

Acidity promotes tumour progression by altering macrophage phenotype in prostate cancer

“…44–46 An immuno-conjugate that integrates urease enzyme with the ability of pH alkalisation in TME is currently undergoing clinical trials in lung cancer but has not been tested in prostate cancer. 47,48 Despite the efficacy of those modalities evident in preclinical studies, no studies had been conducted to investigate their impact on TME. Among the many future therapeutic applications of the current study is to test whether pH-sensitive macrophage-specific immuno-conjugates or nano-systems that specifically target acidic areas rich in macrophages can reduce immunosuppression and increase T cell infiltration.…”

VHH characterization.Recombinant VHHs: Production, characterization and affinity

“…This pilot study challenged here different modes of bacterial production and showed how these can impair VHH key attributes such as yield, homogeneity, structure and function. It is somewhat surprising that an area of such great potential be too often poorly characterized in terms of biophysical properties, despite beautiful biological data obtained with those objects [84][85][86][87][88][89]. Therefore, we embarked in a multi-stage characterization process during which model functional VHHs were thoroughly analyzed for their…”

Development of a noncompetitive idiometric nanobodies phage immumoassay for the determination of fumonisin B 1

“…Construction of a naive nanobodies phage-displayed library was described as Faraji (Faraji et al, 2018). In brief, total RNA was extracted using a total RNA isolation system (Thermo Fisher Scientific, Waltham, MA, USA) from llama peripheral blood lymphocytes.…”