Objective To prepare mouse monoclonal antibodies against the ectodomain of E2 (E2ecto) glycoprotein of Western equine encephalitis virus (WEEV). Methods A prokaryotic expression plasmid pET-28a-WEEV E2ecto was constructed and transformed into BL21 (DE3) competent cells. E2ecto protein was expressed by IPTG induction and presented mainly as inclusion bodies. Then the purified E2ecto protein was prepared by denaturation, renaturation and ultrafiltration. BALB/c mice were immunized with the formulated E2ecto protein using QuickAntibody-Mouse5W as an adjuvant via intramuscular route, boosted once at an interval of 21 days. At 35 days post-immunization, mice with antibody titer above 1×10⁴ were inoculated with E2ecto intraperitoneally, and spleen cells were fused with SP2/0 cells three days later. Hybridoma cells secreting specific monoclonal antibodies were screened by the limited dilution method, and ascites were prepared after intraperitoneal inoculation of hybridoma cells. The subtypes and titers of the antibodies in ascites were assayed by ELISA. The biological activity of the mAb was identified by immunofluorescence assay(IFA) on BHK-21 cells which were transfected with eukaryotic expression plasmid pCAGGS-WEEV-CE3E2E1. The specificity of the antibodies were evaluated with E2ecto proteins from EEEV and VEEV. Results Purified WEEV E2ecto protein was successfully expressed and obtained. Four monoclonal antibodies, 3G6G10, 3D7G2, 3B9E8 and 3D5B7, were prepared, and their subtypes were IgG2c(κ), IgM(κ), IgM(κ) and IgG1(κ), respectively. The titers of ascites antibodies 3G6G10, 3B9E8 and 3D7G2 were 10⁵, and 3D5B7 reached 10⁷. None of the four antibody strains cross-reacted with other encephalitis alphavirus such as VEEV and EEEV. Conclusion Four strains of mouse mAb specifically binding WEEV E2ecto are successfully prepared.
Horses ; Animals ; Mice ; Encephalitis Virus, Western Equine ; Ascites ; Immunosuppressive Agents ; Antibodies, Monoclonal ; Immunoglobulin M

BACKGROUND AND OBJECTIVES

Giant cell tumor of bone (GCTB) is a benign aggressive tumor primarily treated with surgery. Neoadjuvant treatment with denosumab or zoledronic acid is a common adjunct given to down-stage tumors and facilitate limb sparing surgery. This study sought to determine the characteristics, outcomes, and occurrence of complications following resection (RS) or extended curettage (EC) for GCTB of the lower extremities. Correlation of neoadjuvant therapy with the occurrence of complications was also investigated.

This is an analytical cross-sectional study of 30 patients diagnosed with GCTB of the lower extremity treated between 2015 to 2022 in a single tertiary hospital. Functional outcomes were determined using the 1993 version of the Musculoskeletal Tumor Society (MSTS) score. Mean follow-up for all patients was 2.6 years (SD 1.8). Twenty-two patients (73%) underwent resection, while eight (27%) patients underwent extended curettage. Of the 30 patients, 26 (87%) patients received neoadjuvant therapy, with 21 (81%) given denosumab and five (19%) given zoledronic acid.

Functional outcomes were excellent for 23 patients (77%), with no significant difference between RS and EC groups. Nine complications occurred in the RS group, including dehiscence (n=3), superficial infection (n=2), implant failure (n=1), nonunion (n=1), palsy (n=1), and implant irritation (n=1). Five complications occurred in the EC group, four of which were noted to be recurrences, with one case of deep infection. Recurrence was noted to be significantly higher (p=0.0004) in the EC group. Separate correlation analysis showed no significant difference in incidence of complications but found that duration of surgery was significantly longer (p=0.0001), and intraoperative blood loss was significantly higher (p=0.0072) in the RS group. No significant difference (p=0.78) was noted in complication rate between patients given denosumab versus zoledronic acid.

Functional outcomes of EC and RS appear to be comparable, including the incidence of complications. However, recurrence was noted to be significantly higher in EC. There appears to be no clear advantage between denosumab or zoledronic acid for GCTB. As a neoadjuvant medication and/or to control tumor progression, zoledronic acid may be the more economic option especially for patients in developing countries.

Pemphigus is a rare, chronic, life-threatening autoimmune blistering disease characterized by blisters and erosions of the skin and mucous membranes. Rituximab has been approved as a first-line treatment for moderate to severe pemphigus vulgaris. Despite of its efficacy in achieving remission, Rituximab can also lead to serious complications such as Hepatitis B reactivation.

We present a case of a 42-year-old Filipino male with severe pemphigus vulgaris on chronic immunosuppressive therapy. He had a 10-month history of multiple bullae and crusted erosions associated with pruritus and burning pain on the mouth resulting to odynophagia and dysphagia. He is a known case of chronic Hepatitis B with unrecalled vaccination status. On physical examination, Nikolsky and Asboe-Hansen signs were positive. Histopathology show intraepidermal split and row of suprabasal keratinocytes pattern. ELISA showed very high levels (>200 RU/ml) for both anti-desmoglein 1 & 3. DIF was positive for IgG & C3. Prior to Rituximab administration, Tenofovir 300 mg/tab/day was started as pre-emptive therapy. To lessen the dependence on systemic corticosteroids, two infusions of Rituximab 1g 2 weeks apart were then given. Notable improvement was seen, evidenced by absence of new bullae, reduction of affected BSA, from 19% to 5.3% and decreased PDAI (78 to 1) and ABSIS (46.5 to 2.75) four months after treatment. Maintained remission and undetectable Hepatitis B viral load 4 months following the last dose of Rituximab were noted, indicating a positive treatment response to both Rituximab and Tenofovir.

Rituximab represents a viable treatment option even for patients with chronic Hepatitis B. Pre-emptive therapy may be done prior to infusion to prevent hepatitis reactivation. Clinical evidence supports the efficacy and safety of Rituximab in this case where preventive measures are taken.

Herpes zoster is a clinical syndrome associated with reactivation of varicella zoster virus (VZV), often occurring years after VZV infection, and characterized typically by painful grouped vesicles in a dermatomal distribution. Bullous herpes zoster, an atypical presentation of herpes zoster, is a relatively rare phenomenon; to the authors’ knowledge, there have only been eight reports in worldwide literature. We present a case of a 59-year-old female with lupus nephritis who presented with multiple grouped vesicles evolving into large tender bullae filled with serosanguinous fluid on the lateral aspect of the right leg, and dorsal and medial aspects of the right foot, four days after the first dose of 1g of rituximab therapy. The diagnosis of bullous herpes zoster along L4-L5 dermatomes was made based on the clinical presentation and the presence of multinucleated giant cells on Tzanck smear. The giant bullae were drained and dressed, and the patient was treated with valacyclovir at the renally adjusted dose of 1g once a day for seven days and pregabalin 150 mg once daily. After seven days of antiviral treatment, there were no new bullae or vesicles, and the pain improved. Recognizing this atypical presentation of a common disease, especially in patients with an immunocompromised state, highlights the importance of prompt recognition and treatment.
Human ; herpes zoster ; lupus nephritis ; rituximab ; diagnosis, differential

Tumor is a serious threat to human health. At present, surgical resection, chemoradiotherapy, targeted therapy and immunotherapy are the main therapeutic strategies. Monoclonal antibody has gradually become an indispensable drug type in the clinical treatment of cancer due to its high efficiency and low toxicity. Phage antibody library technology (PALT) is a novel monoclonal antibody preparation technique. The recombinant immunoglobulin variable region of heavy chain (VH)/variable region of light chain (VL) gene is integrated into the phage vector, and the antibody is expressed on the phage surface in the form of fusion protein to obtain a diverse antibody library. Through the process of adsorption-elution-amplification, the antibody library can be screened to obtain the antibody molecule with specific binding antigen as well as its gene sequence. PALT has the advantages of short antibody production cycle, strong plasticity of antibody structure, large antibody yield, high diversity and direct production of humanized antibodies. It has been used in screening tumor markers and preparation of antibody drugs for breast cancer, gastric cancer, lung cancer and liver cancer. This article reviews the recent progress and the application of PALT in tumor therapy.
Humans ; Bacteriophages/genetics* ; Immunoglobulin Variable Region/genetics* ; Gene Library ; Antibodies, Monoclonal/therapeutic use* ; Immunotherapy ; Peptide Library

Single chain antibody fragment (scFv) is a small molecule composed of a variable region of heavy chain (VH) and a variable region of light chain (VL) of an antibody, and these two chains are connected by a flexible short peptide. scFv is the smallest functional fragment with complete antigen-binding activity, which contains both the antibody-recognizing site and the antigen-binding site. Compared with other antibodies, scFv has the advantages of small molecular weight, strong penetration, low immunogenicity, and easy expression. Currently, the most commonly used display systems for scFv mainly include the phage display system, ribosome display system, mRNA display system, yeast cell surface display system and mammalian cell display system. In recent years, with the development of scFv in the field of medicine, biology, and food safety, they have also attracted much attention in the sectors of biosynthesis and applied research. This review summarizes the advances of scFv display systems in recent years in order to facilitate scFv screening and application.
Animals ; Immunoglobulin Variable Region/genetics* ; Immunoglobulin Fragments/metabolism* ; Single-Chain Antibodies/metabolism* ; Peptide Library ; Mammals/genetics*

In response to the market demand for therapeutic antibodies, the upstream cell culture scale and expression titer of antibodies have been significantly improved, while the production efficiency of downstream purification process is relatively fall behind, and the downstream processing capacity has become a bottleneck limiting antibody production throughput. Using monoclonal antibody mab-X as experimental material, we optimized the caprylic acid (CA) precipitation process conditions of cell culture fluid and low pH virus inactivation pool, and studied two applications of using CA treatment to remove aggregates and to inactivate virus. Based on the lab scale study, we carried out a 500 L scale-up study, where CA was added to the low pH virus inactivation pool for precipitation, and the product quality and yield before and after precipitation were detected and compared. We found that CA precipitation significantly reduced HCP residuals and aggregates both before and after protein A affinity chromatography. In the aggregate spike study, CA precipitation removed about 15% of the aggregates. A virus reduction study showed complete clearance of a model retrovirus during CA precipitation of protein A purified antibody. In the scale-up study, the depth filtration harvesting, affinity chromatography, low pH virus inactivation, CA precipitation and depth filtration, and cation exchange chromatography successively carried out. The mixing time and stirring speed in the CA precipitation process significantly affected the CA precipitation effect. After CA precipitation, the HCP residue in the low pH virus inactivation solution decreased 895 times. After precipitation, the product purity and HCP residual meet the quality criteria of monoclonal antibodies. CA precipitation can reduce the chromatography step in the conventional purification process. In conclusion, CA precipitation in the downstream process can simplify the conventional purification process, fully meet the purification quality criterion of mab-X, and improve production efficiency and reduce production costs. The results of this study may promote the application of CA precipitation in the purification of monoclonal antibodies, and provide a reference for solving the bottleneck of the current purification process.
Cricetinae ; Animals ; Antibodies, Monoclonal/metabolism* ; Caprylates/chemistry* ; Cell Culture Techniques ; Chromatography, Affinity ; CHO Cells ; Cricetulus ; Chemical Precipitation

The aim of this study was to produce E^rns protein of bovine viral diarrhea virus (BVDV) by using suspensively cultured CHO cells expression system and to analyze the immunogenicity of the purified E^rns protein. In this study, the recombinant eukaryotic expression plasmid pcDNA3.1-BVDV-E^rns was constructed based on the gene sequence of BVDV-1 NADL strain. The E^rns protein was secreted and expressed in cells supernatant after transfecting the recombinant expression plasmid pcDNA3.1-BVDV-E^rns into CHO cells. The expression and purification of the E^rns protein was analyzed by SDS-PAGE, the reactivity was determined with anti-His monoclonal antibodies and BVDV positive serum with Western blotting. Immunogenicity analysis of the E^rns protein was determined after immunizing New Zealand white rabbits, and the serum antibodies were tested by indirect ELISA (iELISA) and indirect immunofluorescence (IFA). The serum neutralizing titer of the immunized rabbits was determined by virus neutralization test. The concentration of the purified E^rns protein was up to 0.886 mg/mL by BCA protein quantification kit. The results showed that the E^rns protein could be detected with anti-His monoclonal antibodies and anti-BVDV sera. Serum antibodies could be detected by iELISA on the 7th day post-prime immunization, and the antibody level was maintained at a high titer until the 28th day post-immunization. The antibody titer was 1:128 000. Furthermore, the expression of the E^rns protein in BVDV-infected MDBK cells could be detected with immunized rabbits sera by IFA. Moreover, antigen-specific neutralizing antibodies of 2.71 log₁₀ was induced in rabbits. In this study, purified BVDV E^rns protein was successfully produced using CHO suspension culture system, and the recombinant protein was proved to have a good immunogenicity, which may facilitate the development of BVD diagnosis method and novel subunit vaccine.
Rabbits ; Animals ; Cricetinae ; Cricetulus ; CHO Cells ; Antibodies, Viral ; Diarrhea Viruses, Bovine Viral/genetics* ; Antibodies, Monoclonal/genetics* ; Diarrhea ; Viral Vaccines/genetics*

A simple, fast, and visual method for detecting antibodies against peste des petits ruminants virus (PPRV) using colloidal gold strips was developed. In this study, the pET-32a-N was transformed into Escherichia coli Rosetta (DE3) for expression. Hybridoma cell lines were generated by fusing SP2/0 myeloma cells with splenocytes from immunized mice with the expressed and purified N protein of PPRV. The PPRV N protein was labeled with colloidal gold particles as the gold-labeled antigen. The N protein served as the gold standard antigen and as the test (T) line-coated antigen, while the monoclonal antibody served as the quality control (C) line-coated antibody to assemble the colloidal gold immunochromatographic test strips for detecting antibodies against the N protein of PPRV. Hybridoma cell line designated as 1F1 was able to stably secrete the monoclonal antibody against the N protein of PPRV. The titer of 1F1 monoclonal antibody in ascites was 1:128 000 determined by indirect enzyme-linked immunosorbent assays (ELISA), and the immunoglobulin subtype of the monoclonal antibody was IgG1, with kappa chain. The obtained monoclonal antibody was able to specifically recognize the N protein of PPRV, as shown by Western blotting and indirect immunofluorescent assay (IFA). The developed colloidal gold test strip method was able to detect PPRV antibodies specifically, and there was no difference between different batches of the test strips. Testing of a total of 122 clinical sera showed that the compliance rate of the test strip with ELISA test was 97.6%.The test strip assay developed in this study has good specificity, reproducibility, and sensitivity, and it can be used for the rapid detection of PPRV antibodies.
Animals ; Mice ; Peste-des-Petits-Ruminants/prevention & control* ; Antibodies, Monoclonal ; Reproducibility of Results ; Peste-des-petits-ruminants virus ; Antibodies, Viral ; Enzyme-Linked Immunosorbent Assay ; Goats

Omalizumab,as a biological agent targeting IgE,is a recombinant humanized monoclonal antibody and the first targeted drug approved for treating moderate-to-severe bronchial asthma.By reviewing one case of aspirin-induced asthma complicated with nasosinusitis and otitis media,we discussed the value of omalizumab in the treatment of asthma and its complications,aiming to provide a reference for clinical practice.
Humans ; Omalizumab/adverse effects* ; Asthma, Aspirin-Induced ; Asthma/drug therapy* ; Otitis Media/drug therapy*