There are many factors that can influence the pharmacokinetics (PK) of a mAb or Fc-fusion molecule with the primary determinant being FcRn-mediated recycling. Through Fab or Fc engineering, IgG-FcRn ...interaction can be used to generate a variety of therapeutic antibodies with significantly enhanced half-life or ability to remove unwanted antigen from circulation. Glycosylation of a mAb or Fc-fusion protein can have a significant impact on the PK of these molecules. mAb charge can be important and variants with pI values of 1-2 unit difference are likely to impact PK with lower pI values being favorable for a longer half-life. Most mAbs display target mediated drug disposition (TMDD), which can have significant consequences on the study designs of preclinical and clinical studies. The PK of mAb can also be influenced by anti-drug antibody (ADA) response and off-target binding, which require careful consideration during the discovery stage. mAbs are primarily absorbed through the lymphatics via convection and can be conveniently administered by the subcutaneous (sc) route in large doses/volumes with co-formulation of hyaluronidase. The human PK of a mAb can be reasonably estimated using cynomolgus monkey data and allometric scaling methods.
Prostacyclin or prostaglandin I2 (PGI2), a metabolite of arachidonic cyclooxygenase pathway, has been demonstrated as an effector of adipocyte differentiation. However, due to its instability in ...biological fluid, it is difficult to evaluate the role of PGI2 in regulating adipocyte differentiation in different stages in culture. Therefore, this study aimed to establish a simple and rapid method for the production of monoclonal antibody against 6-Keto PGF1α, a stable PGI2 metabolite, and its quantification to determine the role of PGI2 in culture medium. Eight-week-old female BALB/c mice were immunized with the hapten of 6-Keto PGF1α and BSA for several weeks until a higher antibody titer (absorbance value > 0.9 at 1000-times dilution) against 6-Keto PGF1α was found. Then, fusion of antibody-producing spleen lymphocytes with SP-2 myeloma cells and thymocytes was performed and cultured in HAT-medium supplemented with hypoxanthine, aminopterin, and thymine. Specific antibody-producing cells (M2-A4-B8-D10) against 6-Keto PGF1α were identified and separated. A standard ELISA calibration curve was developed with 100% reactivity for 6-Keto-PGF 1 α ranging from 0.26 pg to 6.44 ng corresponding to 90% and 10% of the maximum binding capacity for the immobilized antigen respectively. This method can easily be applied to monitor PGI2 regulation in different stages of cultured adipocytes to reveal the regulatory roles of PGI2 in maintaining homeostasis and adipocyte differentiation.
•The monitoring of adipocyte differentiation effector PGI2 in culture was difficult due to its instability.•A new ELISA method has been developed to quantify 6-Keto PGF1α, a stable metabolite of PGI2, to monitor the role of PGI2 in adipocyte differentiation.•A new hybridoma cell line producing monoclonal antibody against 6-Keto PGF1α has been generated.
Migraine is a common and disabling primary headache disorder. Several drugs targeting calcitonin gene-related peptide (CGRP), such as erenumab (an anti-CGRP receptor mAb), have been developed ...recently. However, the real-world effects of erenumab are not well understood.
To assess the clinical effectiveness and safety of erenumab for reducing migraine intensity and frequency in the real world.
A systematic search of PubMed, Scopus, Web of Science and the Cochrane Library was conducted from inception to December 2023. Studies estimating the real-world effect of erenumab on monthly migraine days (MMD), monthly headache days (MHD), headache impact test (HIT-6), number of days in medication (NDM), acute monthly intake (AMI), pain intensity (PI) and safety outcomes were included. Meta-analyses of proportions or mean differences were performed.
Fifty-three studies were included. At 3-months, the effect was −7.18 days for MMD, −6.89 days for MHD, −6.97 for HIT-6, -6.22 days for NDM, −15.75 for AMI, and −1.71 for PI. Generally, the effect at 6- and 12-months increased slightly and gradually. The MMD/MHD response rates revealed that approximately one-third of patients exhibited a response greater than 30%, while one-sixth demonstrated a response exceeding 50%. Additionally, 3–4% of patients achieved a response rate of 100%. Adverse event rates were 0.34 and 0.43 at 6- and 12-months, respectively.
This study provides strong evidence of the effectiveness and safety of erenumab in the real world; to our knowledge, this is the first real-world meta-analysis specific to erenumab. Erenumab represents a solid therapeutic option for physicians.
•Potential risks associated with extractables and leachables from 3D printed columns evaluated.•3D printed columns functionalised with protein A and SO3 ligands for use in mAb capture and ...polishing.•Successful mAb captured with recovery yield > 85 % and 70 % in affinity and cation exchange mode, respectively.•Negligible leakage of protein A from 3D printed column and unchanged column performances over 20 cycles.•High HCP clearance (log reduction ∼ 2.7) demonstrated with no formation of aggregates.
3D printing offers the unprecedented ability to fabricate chromatography stationary phases with bespoke 3D morphology as opposed to traditional packed beds of spherical beads. The restricted range of printable materials compatible with chromatography is considered a setback for its industrial implementation. Recently, we proposed a novel ink that exhibits favourable printing performance (printing time ∼100 mL/h, resolution ∼200 µm) and broadens the possibilities for a range of chromatography applications thanks to its customisable surface chemistry. In this work, this ink was used to fabricate 3D printed ordered columns with 300 µm channels for the capture and polishing of therapeutic monoclonal antibodies. The columns were initially assessed for leachables and extractables, revealing no material propensity for leaching. Columns were then functionalised with protein A and SO3 ligands to obtain affinity and strong cation exchangers, respectively. 3D printed protein A columns showed >85 % IgG recovery from harvested cell culture fluid with purities above 98 %. Column reusability was evaluated over 20 cycles showing unaffected performance. Eluate samples were analysed for co-eluted protein A fragments, host cell protein and aggregates. Results demonstrate excellent HCP clearance (logarithmic reduction value of > 2.5) and protein A leakage in the range of commercial affinity resins (<100 ng/mg). SO3 functionalised columns employed for polishing achieved removal of leaked Protein A (down to 10 ng/mg) to meet regulatory expectations of product purity. This work is the first implementation of 3D printed columns for mAb purification and provides strong evidence for their potential in industrial bioseparations.
The escalating epidemic of PRRSV-1 in China has prompted widespread concern regarding the evolution of strains, disparities in pathogenicity to herds, and immunological detection of emerging strains. ...The nucleocapsid (N) protein, as a highly conserved protein with immunogenic properties in PRRSV, is a subject of intensive study. In this research, the recombinant His-N protein was expressed based on the N gene of PRRSV-1 using a prokaryotic expression system and then administered to BALB/c mice. A cell fusion protocol was implemented between SP2/0 cells and splenocytes, resulting in the successful screening of a monoclonal antibody against the N protein, designated as mAb 2D7, by indirect ELISA. Western Blot analysis and Indirect Immunofluorescence Assay (IFA) confirmed that mAb 2D7 positively responded to PRRSV-1. By constructing and expressing a series of truncated His-fused N proteins, a B-cell epitope of N protein, 59-AAEDDIR-65, was identified. A sequence alignment of two genotypes of PRRSV revealed that this epitope is relatively conserved in PRRSV, yet more so in genotype 1. Cross-reactivity analysis by Western blot analysis demonstrated that the B-cell epitope containing D62Y mutation could not be recognized by mAb 2D7. The inability of mAb 2D7 to recognize the epitope carrying the D62Y mutation was further determined using an infectious clone of PRRSV. This research may shed light on the biological significance of the N protein of PRRSV, paving the way for the advancement of immunological detection and development of future recombinant marker vaccine.
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•A monoclonal antibody, 2D7, against the N protein of PRRSV-1 was generated by immunizing with the recombinant N protein.•The linear B-cell epitope 59-AAEDDIR-65 recognized by 2D7 was identified.•D62 in the epitope 59-AAEDDIR-65 is the crucial amino acid recognized by 2D7.
To overcome limitations with respect to the low sensitivity of rapid immunoassay methods due to dilution of the extract in extraction solution, ultra-sensitive antibodies are needed. The ...linker-tethering site between the target and carrier protein, the length of the spacer arm, and the atomic charge of the linker-tethering site between the target and spacer arm in haptens design play a pivotal role in the preparation of ultra-sensitive antibodies. In this study, carbendazim (CBZ), a systemic broad-spectrum fungicidal pesticide, was used as model compound. 2-Aminobenzimidazole was chosen as the common skeletal structure and reacted with different groups, such as alkanes and urine groups, to form haptens H1 (previously reported), H2 (novel), and H3 (novel), respectively. Subsequently, eight monoclonal antibodies (mAbs) were generated using these three haptens, which exhibited notable variation in sensitivity. The half maximal inhibitory concentration (IC50) value of mAb 4B11 based on hapten H3 against CBZ was 0.04 ng/mL, which was seven times better than that of mAb 5B10 (IC50 value of 0.28 ng/mL) prepared using hapten H2 and 129 times better than that of mAb 6D5 (IC50 value of 5.15 ng/mL) prepared using hapten H1. Finally, the optimal antigen–antibody combination was employed to establish a sensitive colloidal gold lateral flow immunoassay (CG-LFA) for CBZ detection in vegetables and fruits with convenient sample pretreatment. The developed CG-LFA shows promising practical utility and prospects for application due to its low limit of detection (0.10–0.18 ng/mL) and high recovery ratios (76.0%–96.1%) in six different samples.
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•A novel hapten design strategy focuses on the link site and spacer arm length of the target compound.•An ultra-sensitive monoclonal antibody (mAb) 4B11 against carbendazim was prepared.•A sensitive colloidal gold lateral flow immunoassay in fruits and vegetables was developed.
Gizzerosine is a biogenic amine produced in fish meal drying process and posted higher mortality due to gizzard erosion in poultry than histamine. However, it is difficult to obtain gizzerosine and ...achieve sensitive practical detection due to its simple structure. Herein, a monoclonal antibody (mAb) specific to gizzerosine was generated based on the new structural design and a fluorescence immunosensor for sensitive and on-site detection of gizzerosine in feed was first established. Molecular modeling of the three-dimensional (3D) structure and surface electrostatic potential of gizzerosine indicated that the carbonyl group of gizzerosine hapten might affect the important sites of antigen-antibody interactions. The proposed structure was used to obtain the sensitive and specific mAb with IC50 of 3.88 ng/mL in indirect competitive ELISA which was approximately 100-fold lower than that of direct competitive ELISA. Considering the practical application scenarios, a fluorescence immunosensor based on microporous dry method integrated with independent quality control line was established to improve detection stability. Under the optimum conditions, the proposed immunosensor showed a good linear relationship from 1.10 to 19.78 ng/mL and provided a low detection limit of 50 ng/g which was approximately 80-fold lower than the maximum recommended amount (0.4 mg/kg) of gizzerosine in feed. The recoveries of 6 kinds of feed ranged from 83.1 % to 114.3 %, which was in good consistence with that of UHPLC–MS/MS. Overall, this work provides a fast, cost-effective and reliable on-site tool for rapid screening of gizzerosine residues in feed samples.
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•A novel hapten different from the original gizzerosine was designed for the first time.•A highly sensitive and specific anti-gizzerosine monoclonal antibody based on the novel hapten was prepared.•Relationship between antibody and hapten was studied by molecular modeling.•A fluorescence immunosensor was firstly developed for the on-site detection of gizzerosine.•The microporous dry method integrated with independent quality control line can be used for on-site detection.
Monoclonal antibody technology plays a vital role in biomedical and immunotherapy, which greatly promotes the study of the structure and function of genes and proteins. To date, monoclonal antibodies ...have gone through four stages: murine monoclonal antibody, chimeric monoclonal antibody, humanised monoclonal antibody and fully human monoclonal antibody; thousands of monoclonal antibodies have been used in the fields of biology and medicine, playing a special role in the pathogenesis, diagnosis and treatment of disease. In this review, we compare the advantages and disadvantages of hybridoma technology, phage display technology, ribosome display technology, transgenic mouse technology, single B cell monoclonal antibody generation technologies, and forecast the promising applications of these technologies in clinical medicine, disease diagnosis and tumour treatment.
Since the first use of Chinese hamster ovary (CHO) cells for recombinant protein expression, production processes have steadily improved through numerous advances. In this review, we have highlighted ...several key milestones that have contributed to the success of CHO cells from the beginning of their use for monoclonal antibody (mAb) expression until today. The main factors influencing the yield of a production process are the time to accumulate a desired amount of biomass, the process duration, and the specific productivity. By comparing maximum cell densities and specific growth rates of various expression systems, we have emphasized the limiting parameters of different cellular systems and comprehensively described scientific approaches and techniques to improve host cell lines. Besides the quantitative evaluation of current systems, the quality-determining properties of a host cell line, namely post-translational modifications, were analyzed and compared to naturally occurring polyclonal immunoglobulin fractions from human plasma. In summary, numerous different expression systems for mAbs are available and also under scientific investigation. However, CHO cells are the most frequently investigated cell lines and remain the workhorse for mAb production until today.
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