Structure-guided antibody cocktail for prevention and treatment of COVID-19.

Development of effective therapeutics for mitigating the COVID-19 pandemic is a pressing global need. Neutralizing antibodies are known to be effective antivirals, as they can be rapidly deployed to prevent disease progression and can accelerate patient recovery without the need for fully developed host immunity. Here, we report the generation and characterization of a series of chimeric antibodies against the receptor-binding domain (RBD) of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein. Some of these antibodies exhibit exceptionally potent neutralization activities in vitro and in vivo, and the most potent of our antibodies target three distinct non-overlapping epitopes within the RBD. Cryo-electron microscopy analyses of two highly potent antibodies in complex with the SARS-CoV-2 spike protein suggested they may be particularly useful when combined in a cocktail therapy. The efficacy of this antibody cocktail was confirmed in SARS-CoV-2-infected mouse and hamster models as prophylactic and post-infection treatments. With the emergence of more contagious variants of SARS-CoV-2, cocktail antibody therapies hold great promise to control disease and prevent drug resistance.

Bivalent mRNA vaccine effectiveness against SARS-CoV-2 variants of concern.

BACKGROUND: Sequential infections with SARS-CoV-2 variants such as Alpha, Delta, Omicron and its sublineages may cause high morbidity, so it is necessary to develop vaccines that can protect against both wild-type (WT) virus and its variants. Mutations in SARS-CoV-2's spike protein can easily alter viral transmission and vaccination effectiveness. METHODS: In this study, we designed full-length spike mRNAs for WT, Alpha, Delta, and BA.5 variants and integrated each into monovalent or bivalent mRNA-lipid nanoparticle vaccines. A pseudovirus neutralization assay was conducted on immunized mouse sera in order to examine the neutralizing potential of each vaccine. RESULTS: Monovalent mRNA vaccines were only effective against the same type of virus. Interestingly, monovalent BA.5 vaccination could neutralize BF.7 and BQ.1.1. Moreover, WT, Alpha, Delta, BA.5, and BF.7 pseudoviruses were broadly neutralized by bivalent mRNA vaccinations, such as BA.5 + WT, BA.5 + Alpha, and BA.5 + Delta. In particular, BA.5 + WT exhibited high neutralization against most variants of concern (VOCs) in a pseudovirus neutralization assay. CONCLUSIONS: Our results show that combining two mRNA sequences may be an effective way to develop a broadly protective SARS-CoV-2 vaccine against a wide range of variant types. Importantly, we provide the optimal combination regimen and propose a strategy that may prove useful in combating future VOCs.

Effect of extended field-of-view approaches on the accuracy of stopping power ratio estimation for single-energy computed tomography simulators.

BACKGROUND: Extended field-of-view (eFOV) methods have been proposed to generate larger demonstration FOVs for computed tomography (CT) simulators with a limited scanning FOV (sFOV) size in order to ensure accurate dose calculation and patient collision avoidance. Although the efficacy of these strategies has been evaluated for photon applications, the effect of stopping power ratio (SPR) estimation on proton therapy has not been studied. This study investigated the effect of an eFOV approach on the accuracy of SPR to water estimation in homogeneous and heterogeneous phantoms. MATERIALS AND METHODS: To simulate patient geometries, tissue-equivalent material (TEM) and customized extension phantoms were used. The TEM phantom supported various rod arrangements through predefined holes. Images were reconstructed to three FOV sizes using a commercial eFOV technique. A single-energy CT stoichiometric method was used to generate Hounsfield unit (HU) to SPR (HU-to-SPR) conversion curves for each FOV. To investigate the effect of rod location in the sFOV and eFOV regions, eight TEM rods were placed at off-center distances in the homogeneous phantom and scanned individually. Similarly, 16 TEM rods were placed in the heterogeneous TEM phantom and scanned simultaneously. RESULTS: The conversion curves derived from the sFOV and eFOV data were identical. The average SPR differences of soft-tissue, bone, and lung materials for rods placed at various off-center locations were 3.3%, 4.8%, and 39.6%, respectively. In the heterogeneous phantom, the difference was within 1.0% in the absence of extension. However, in the presence of extension, the difference increased to 2.8% for all rods, except for lung materials, whose difference was 4.8%. CONCLUSIONS: When an eFOV method is used, the SPR variation in phantoms considerably increases for all TEM rods, especially for lung TEM rods. This phenomenon may substantially increase the uncertainty of HU-to-SPR conversion. Therefore, image reconstruction with a standard FOV size is recommended.

Monoclonal antibodies against S2 subunit of spike protein exhibit broad reactivity toward SARS-CoV-2 variants.

BACKGROUND: The variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) harbor diverse spike (S) protein sequences, which can greatly influence the efficacies of therapeutics. Therefore, it would be of great value to develop neutralizing monoclonal antibodies (mAbs) that can broadly recognize multiple variants. METHODS: Using an mRNA-LNP immunization strategy, we generated several mAbs that specifically target the conserved S2 subunit of SARS-CoV-2 (B-S2-mAbs). These mAbs were assessed for their neutralizing activity with pseudotyped viruses and binding ability for SARS-CoV-2 variants. RESULTS: Among these mAbs, five exhibited strong neutralizing ability toward the Gamma variant and also recognized viral S proteins from the Wuhan, Alpha, Beta, Gamma, Delta and Omicron (BA.1, BA.2 and BA.5) variants. Furthermore, we demonstrated the broad reactivities of these B-S2-mAbs in several different applications, including immunosorbent, immunofluorescence and immunoblotting assays. In particular, B-S2-mAb-2 exhibited potent neutralization of Gamma variant (IC50 = 0.048 µg/ml) in a pseudovirus neutralization assay. The neutralizing epitope of B-S2-mAb-2 was identified by phage display as amino acid residues 1146-1152 (DSFKEEL) in the S2 subunit HR2 domain of SARS-CoV-2. CONCLUSION: Since there are not many mAbs that can bind the S2 subunit of SARS-CoV-2 variants, our set of B-S2-mAbs may provide important materials for basic research and potential clinical applications. Importantly, our study results demonstrate that the viral S2 subunit can be targeted for the production of cross-reactive antibodies, which may be used for coronavirus detection and neutralization.

A booster dose of Delta × Omicron hybrid mRNA vaccine produced broadly neutralizing antibody against Omicron and other SARS-CoV-2 variants.

BACKGROUND: With the continuous emergence of new SARS-CoV-2 variants that feature increased transmission and immune escape, there is an urgent demand for a better vaccine design that will provide broader neutralizing efficacy. METHODS: We report an mRNA-based vaccine using an engineered "hybrid" receptor binding domain (RBD) that contains all 16 point-mutations shown in the currently prevailing Omicron and Delta variants. RESULTS: A booster dose of hybrid vaccine in mice previously immunized with wild-type RBD vaccine induced high titers of broadly neutralizing antibodies against all tested SARS-CoV-2 variants of concern (VOCs). In naïve mice, hybrid vaccine generated strong Omicron-specific neutralizing antibodies as well as low but significant titers against other VOCs. Hybrid vaccine also elicited CD8+/IFN-γ+ T cell responses against a conserved T cell epitope present in wild type and all VOCs. CONCLUSIONS: These results demonstrate that inclusion of different antigenic mutations from various SARS-CoV-2 variants is a feasible approach to develop cross-protective vaccines.

Antibody cocktail effective against variants of SARS-CoV-2.

BACKGROUND: Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), an RNA virus with a high mutation rate. Importantly, several currently circulating SARS-CoV-2 variants are associated with loss of efficacy for both vaccines and neutralizing antibodies. METHODS: We analyzed the binding activity of six highly potent antibodies to the spike proteins of SARS-CoV-2 variants, assessed their neutralizing abilities with pseudovirus and authentic SARS-CoV-2 variants and evaluate efficacy of antibody cocktail in Delta SARS-CoV-2-infected hamster models as prophylactic and post-infection treatments. RESULTS: The tested RBD-chAbs, except RBD-chAb-25, maintained binding ability to spike proteins from SARS-CoV-2 variants. However, only RBD-chAb-45 and -51 retained neutralizing activities; RBD-chAb-1, -15, -25 and -28 exhibited diminished neutralization for all SARS-CoV-2 variants. Notably, several cocktails of our antibodies showed low IC50 values (3.35-27.06 ng/ml) against the SARS-CoV-2 variant pseudoviruses including United Kingdom variant B.1.1.7 (Alpha), South Africa variant B.1.351 (Beta), Brazil variant P1 (Gamma), California variant B.1.429 (Epsilon), New York variant B.1.526 (Iota), and India variants, B.1.617.1 (Kappa) and B.1.617.2 (Delta). RBD-chAb-45, and -51 showed PRNT50 values 4.93-37.54 ng/ml when used as single treatments or in combination with RBD-chAb-15 or -28, according to plaque assays with authentic Alpha, Gamma and Delta SARS-CoV-2 variants. Furthermore, the antibody cocktail of RBD-chAb-15 and -45 exhibited potent prophylactic and therapeutic effects in Delta SARS-CoV-2 variant-infected hamsters. CONCLUSIONS: The cocktail of RBD-chAbs exhibited potent neutralizing activities against SARS-CoV-2 variants. These antibody cocktails are highly promising candidate tools for controlling new SARS-CoV-2 variants, including Delta.

Monoclonal Antibodies against Nucleocapsid Protein of SARS-CoV-2 Variants for Detection of COVID-19.

Mitigation strategies of the coronavirus disease 2019 (COVID-19) pandemic have been greatly hindered by the continuous emergence of SARS-CoV-2 variants. New sensitive, rapid diagnostic tests for the wide-spectrum detection of viral variants are needed. We generated a panel of 41 monoclonal antibodies against the SARS-CoV-2 nucleocapsid protein (NP) by using mice hybridoma techniques. Of these mAbs, nine exhibited high binding activities and were applied in latex-based lateral flow immunoassays (LFIAs). The LFIAs utilizing NP-mAb-7 and -40 had the best sensitivity and lowest limit of detection: 8 pg for purified NP and 625 TCID50/mL for the authentic virus (hCoV-19/Taiwan/4/2020). The specificity tests showed that the NP-mAb-40/7 LFIA strips did not cross-react with five human coronavirus strains or 20 other common respiratory pathogens. Importantly, we found that 10 NP mutants, including alpha (B.1.1.7), beta (B.1.351), gamma (P.1), and delta (B.1.617.2) variants, could be detected by NP-mAb-40/7 LFIA strips. A clinical study (n = 60) of the NP-mAb-40/7 LFIA strips demonstrated a specificity of 100% and sensitivity of 90% in infected individuals with cycle threshold (Ct) values < 29.5. These anti-NP mAbs have strong potential for use in the clinical detection of SARS-CoV-2 infection, whether the virus is wild-type or a variant of concern.

[Evidence-Based Nursing Care of Older Adult Patient With Postoperative Delirium and Hip Fracture].

Hip fracture commonly occurs in adult patients over 65 years old at a prevalence rate that is estimated to be 756 per 100 thousand cases. Thus, hip fracture surgery is one of the most common emergency operations in older adult populations. In addition, the incidence rate in older adults of post-operative delirium, which leads to symptoms of disturbance related to cognition, attention, perception, logic, memory, psychological activities, mood, and sleep, has been reported as 5%-61%. The many possible complications of post-operative delirium, including death, increase medical costs and family burdens if not managed properly. Proper management involves healthcare providers initiating early assessments, reducing accelerated factors, and providing appropriate care. As diagnosing and differentiating post-operative delirium in clinical practice is difficult, this condition is easily neglected by healthcare teams, resulting in adequate care not being provided to this population. The aim of this paper was to review the definition, relevant physiological and pathological mechanisms and etiologies, and medical management and nursing care of post-operative delirium using an evidence-based literature review. Suggestions for healthcare providers to improve the detection and management of post-operative delirium include using appropriate evaluation tools to detect and diagnose high-risk patients as early as possible, implementing older-adult life planning strategies, and conducting medical consultations. Furthermore, healthcare providers may initiate pain control, nutrient and body fluid supplementation, and sensory/cognition enhancement therapies to reduce the incidence of delirium, length of hospital stay, complications, and in-hospital mortality, thereby improving the quality of care provided to older adult patients with hip fractures and their caregivers.

Novel monoclonal antibody against integrin α3 shows therapeutic potential for ovarian cancer.

Ovarian cancer has a high recurrence rate after platinum-based chemotherapy. To improve the treatment of ovarian cancer and identify ovarian cancer-specific antibodies, we immunized mice with the human ovarian carcinoma cell line, SKOV-3, and generated hybridoma clones. Several rounds of screening yielded 30 monoclonal antibodies (mAbs) with no cross-reactivity to normal cells. Among these mAbs, OV-Ab 30-7 was found to target integrin α3 and upregulate p53 and p21, while stimulating the apoptosis of cancer cells. We further found that binding of integrin α3 by OV-Ab 30-7 impaired laminin-induced focal adhesion kinase phosphorylation. The mAb alone or in combination with carboplatin and paclitaxel inhibited tumor progression and prolonged survival of tumor-bearing mice. Moreover, immunohistochemical staining of ovarian patient specimens revealed higher levels of integrin α3 in cancer cells compared with normal cells. By querying online clinical databases, we found that elevated ITGA3 expression in ovarian cancer is associated with poor prognosis. Taken together, our data suggest that the novel mAb, OV-Ab 30-7, may be considered as a potential therapeutic for ovarian cancer.

[Nursing Experience of a Patient With Breast Cancer Who Suffered From a Fungating Wound].

This report discusses an experience of taking care of a breast cancer patient with rapidly deteriorating, fungating wounds and herpes simplex virus wounds and describes the physical and psychological effects on the patient and the related decreases in the quality of life of both the patient and her caregivers. Nursing care was implemented from December 14th, 2017 to January 23rd, 2018. Data collection was performed through direct caregiving, observation, interviews, and chart review. Three major problems were identified: difficulties with wound care, psychological distress of the patient, and the coping problems of the caregivers. Based on these problems, nursing interventions were implemented. During the period, fungating wound care guidelines were used to teach the patient and her caregivers the core principles of fungating wound management. Meanwhile, the COPE framework (creativity, optimism, planning, and expert information) was applied to train the patient and her caregivers how to develop problem-solving skills and build self-confidence. Finally, the patient and her family successfully overcame these challenges. The patient was relieved of stress and anxiety, became better able to self-manage her symptoms, sustain hope for the future, and improve her perception of body self-image. We suggested that the patient and her family be considered a single, supportive unit and then helped them cope with the disease and build self-care confidence in order to improve their life quality and to coexist with the disease. We hope that our clinical experience will be taken as a reference by patient caregivers.

[Effects of an Interdisciplinary Care Program on Improving the Return-to-Treatment Rate Among Cancer Patients].

BACKGROUND & PROBLEMS: The return-to-treatment rate is an important indicator of treatment outcome and care effectiveness in cancer patients. The return-to-treatment rates for patients at National Taiwan University Hospital (NTUH) in 2011 and 2012 were 38.5% and 33.3%, respectively. In order to improve the quality of care that is provided to patients, we reviewed NTUH's current clinical case management protocols for handling patients who refused treatment and then identified and resolved the potential problems in these protocols. PURPOSE: To raise the return-to-treatment rate above 45% by 2013. RESOLUTION: We developed four new interventions to improve the return-to-treatment rate. Firstly, we assembled a quality care team that monitored the rates of patient return to treatment on a monthly basis and reminded case managers to follow up with patients regularly. Secondly, we introduced new protocols for case managers that facilitated the ongoing analysis of the reasons that patients elect not to return to treatment. Thirdly, we delivered regular education programs for case managers addressing good quality and quantity care for cancer patients. Finally, we developed an interdisciplinary liaison care program for patients. RESULTS: After implementing these four interventions, the return-to-treatment rate improved to 48% in 2013. CONCLUSIONS: This improvement project demonstrated that integrating an interdisciplinary team, assembling a quality care team, implementing new protocols to help cancer patients who refuse to commence / continue treatment, providing regular education to clinical case managers, and enacting an interdisciplinary care program were all helpful to improving the effectiveness of cancer care services and the return-to-treatment rate of cancer patients.

Outcomes and prognostic factors for surgery followed by modern radiation therapy in parotid gland carcinomas.

OBJECTIVE: To evaluate the outcomes and prognostic factors in patients with parotid gland cancers treated with adjuvant radiotherapy with or without chemotherapy. METHODS: Eighty-five patients with parotid gland cancers were identified between October 2001 and September 2011. The median radiation dose was 66 Gy (range, 9-76 Gy). The outcomes assessment included overall survival, locoregional control, distant metastasis-free survival and disease-free survival. RESULTS: The stage distribution was 20 patients  (23.5%) in stage I, 28 (32.9%) stage II, 14 (16.5%) stage III and 23 (27.1%) stage IV. Fifty-five patients (64.7%) had positive margins and 23 patients (27.1%) had close margins (<0.5 cm). Lymph node extracapsular spreading occurred in nine patients. The adjuvant therapy included radiotherapy alone in 47 patients (55.3%) and concurrent chemoradiotherapy in 38 patients (44.7%). With a median follow-up of 4.5 years (range, 0.4-11 years), the 5-year overall survival, locoregional control, distant metastasis-free survival and disease-free survival were 82.0, 88.4, 82.4 and 77.5%, respectively. Based on multivariate analysis, N1/N2 was a significant negative prognostic factor for distant metastasis-free survival, disease-free survival and overall survival. Perineural invasion was a significant negative prognostic factor for locoregional control, distant metastasis-free survival and disease-free survival. Patients 50 years or older had significantly worse distant metastasis-free survival, disease-free survival and overall survival. CONCLUSIONS: Surgery and radiotherapy treatment could achieve excellent outcomes in a modern cohort. However, N1/N2, perineural invasion and age ≥50 years, but not positive margins, are significant factors associated with a worse prognosis.

Pressure injury risk factors in patients undergoing general anesthesia surgeries.

BACKGROUND: Pressure injuries result from prolonged pressure and lead to tissue damage, infections, extended recovery times, and an economic burden. PURPOSE: To explore risk factors for pressure injuries in patients who underwent surgery under general anesthesia. METHODS: This retrospective study included patients who underwent surgery at a regional educational hospital in southern Taiwan from January 1, 2018, through December 31, 2018. RESULTS: A comprehensive multivariate analysis was used to identify the prominent risk factors for pressure injury among the 11 231 patients enrolled in this study. These risk factors were an age of ≥65 years; surgery duration of >120 minutes; diastolic blood pressure of <60 mm Hg for >30 minutes during surgery; intraoperative use of dopamine, norepinephrine, or epinephrine as vasopressors; American Society of Anesthesiologists physical classification of III or higher; minimum intraoperative body temperature of ≤35°C; blood loss of >500 mL; and a supine or prone surgical position. CONCLUSIONS: This study identified several pressure injury risk factors related to surgical conditions and patient characteristics. Surgical teams must monitor, control, and manage these factors, prioritize staff education, and adopt preventive protocols.

Base-mediated ketenimine formation from N-sulfonylthioimidates for the synthesis of 5-amino-1-vinyl/aryl-1,2,3-triazoles.

N-Sulfonylthioimidate was converted to ketenimine under basic conditions. The reaction with vinyl/aryl azides was induced to cause dipolar cycloaddition to form 5-amino-1-vinyl/aryl-1,2,3-triazoles. The advantages of this method are high efficiency, structural diversity of products favorable yields and applicability to gram-scale operations.

Dual inhibition of BTLA and PD-1 can enhance therapeutic efficacy of paclitaxel on intraperitoneally disseminated tumors.

BACKGROUND: Expression of immune checkpoints in the tumor microenvironment is one mechanism underlying paclitaxel (PTX) chemoresistance. This study aimed to investigate whether the addition of checkpoint blockade to PTX can improve the therapeutic efficacy against apparently disseminated intraperitoneal tumors. METHODS: We analyzed the in vivo expression of various immune checkpoints in CD3+CD8+ cytotoxic T cells from tumor-bearing mice treated with or without PTX and validated the tumor-killing activities of selected checkpoint-expressing T-cell subpopulations ex vivo. The regulation of selected checkpoints was investigated in vitro. The therapeutic effects of inhibition of a targeted checkpoint pathway with antibodies added to PTX therapy were examined. RESULTS: CD3+CD8+ T cells expressed with herpes virus entry mediator (HVEM), programmed cell death 1 (PD-1), and T-cell immunoglobulin domain and mucin domain 3 (TIM-3) in tumor-bearing hosts treated with PTX had effective tumoricidal activities. In addition to PTX and cytokines, B and T lymphocyte attenuator (BTLA) or homologous to lymphotoxin, exhibits inducible expression and competes with herpes simplex virus (HSV) glycoprotein D for binding to HVEM, a receptor expressed on T lymphocytes (LIGHT) interacting with HVEM can regulate the expression of PD-1 on CD3+CD8+ T cells. Interleukin (IL)-15 increased the percentage of HVEMhighgranzyme B (GZMB)+ cells among CD3+CD8+ T cells, which was suppressed by the BTLA/HVEM signal. LIGHT induced the percentage of HVEM+GZMB+ cells but not HVEMhighGZMB+ cells among CD3+CD8+ T cells. Expression of IL-15, BTLA, or LIGHT was detected in CD19+ B cells and regulated by damage-associated molecular patterns/Toll-like receptor interactions. In the tumor-bearing hosts treated with PTX, certain proportions of BTLA+ B or PD-1+ T lymphocytes were still noted. When dual inhibition of BTLA and PD-1 was added to PTX, the antitumor effects on intraperitoneally disseminated tumors can be significantly improved. CONCLUSIONS: Dual blockade of BTLA on B cells and PD-1 on cytotoxic T cells may have clinical potential for enhancing the efficacy of PTX in the treatment of tumors with intraperitoneal spread, including epithelial ovarian carcinomas.

Post-irradiation sarcoma after definitive radiation therapy for nasopharyngeal carcinoma.

BACKGROUND AND PURPOSE: Postirradiation sarcoma (PIS) is a rare radiation-induced malignancy after nasopharyngeal carcinoma (NPC) treatment. MATERIALS AND METHODS: We retrospectively screened 9,185 NPC patients between 2000 and 2020 and identified 41 patients with PIS according to the modified Cahan's criteria: (1) the PIS must have arisen within a previous radiation field; (2) a latent period must have existed; (3) histologically proved sarcoma; (4) the tissue in which the PIS arose must have been healthy prior to the radiation. The initial radiation therapy techniques used were 2D (25; 61.0%), 3D (7; 17.1%), and IMRT (9; 22%). RESULTS: The time (year) from radiotherapy (RT) to PIS was longer when using 2D or 3D irradiation techniques (median, 14.2; range, 3.4-28.1; Q1-Q3, 8.6-19.7) than when using IMRT (median, 6.6; range, 3.8-15.7; Q1-Q3, 4.5-11.7; P =.026). The time (year) from RT to PIS diagnosis was significantly longer when using lower radiation energy from cobalt-60 (median, 15.8; range, 10.4-28.4; Q1-Q3, 12.5-23.8) than when using a higher radiation energy of 6 or 10 MV (median, 10.2; range, 3.4-23.3; Q1-Q3, 6.5-16.1; P =.006). The 2-year overall survival rates for patients who underwent surgery, radical radiotherapy, systemic therapy alone and no treatment were 60.7 %, 42.9 %, 0 % and 0 %, respectively (P =.000). Of the 3 retrievable initial RT dosimetry plans for NPC, the D95 values (dose that covers 95 % of the PIS volume) for PIS were 6267, 6344 and 5820 cGy, respectively. CONCLUSION: High radiation energy and modern techniques may shorten NPC PIS latency. Surgery may be associated with improved survival if feasible.

Vertebral artery sparing volumetric modulated arc therapy in nasopharyngeal carcinoma.

Vascular stenosis is a late radiation complication that develops in long-term survivors of nasopharyngeal carcinoma. Vertebral arteries (VAs) are major vessels responsible for posterior circulation. In this study, we evaluated the feasibility of VA-sparing volumetric modulated arc therapy (VMAT) techniques. A total of 20 patients with nasopharyngeal carcinoma treated by a TrueBeam linear accelerator were enrolled in this study. The original VMAT plan was designed without the contouring of VAs as organs at risk (OARs). The same image set of the original VMAT plan was used to contour the VAs for each patient. A new VA-sparing VMAT plan was developed by avoiding VAs as OARs. Finally, a paired t-test was used to compare the dosimetric differences. The VA-sparing VMAT plan had similar target coverage and dose to those of other OARs. The VA-sparing plan yielded a significantly low VA dose from 53 to 40 Gy, with V35Gy changing from 97% to 56%, V50Gy changing from 67% to 35%, and V63Gy changing from 15% to approximately 7%-10% (p < 0.001 for all comparisons). VAs should be correctly identified as OARs. Photon VMAT with VA sparing can help substantially decrease the VA dose.

Broadly neutralizing antibodies against Omicron variants of SARS-CoV-2 derived from mRNA-lipid nanoparticle-immunized mice.

The COVID-19 pandemic continues to threaten human health worldwide as new variants of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerge. Currently, the predominant circulating strains around the world are Omicron variants, which can evade many therapeutic antibodies. Thus, the development of new broadly neutralizing antibodies remains an urgent need. In this work, we address this need by using the mRNA-lipid nanoparticle immunization method to generate a set of Omicron-targeting monoclonal antibodies. Five of our novel K-RBD-mAbs show strong binding and neutralizing activities toward all SARS-CoV-2 variants of concern (Alpha, Beta, Gamma, Delta and Omicron). Notably, the epitopes of these five K-RBD-mAbs are overlapping and localized around Y453 and F486 of the spike protein receptor binding domain (RBD). Chimeric derivatives of the five antibodies (K-RBD-chAbs) neutralize Omicron sublineages BA.1 and BA.2 with low IC50 values ranging from 5.7 to 12.9 ng/mL. Additionally, we performed antibody humanization on broadly neutralizing chimeric antibodies to create K-RBD-hAb-60 and -62, which still retain excellent neutralizing activity against Omicron. Our results collectively suggest that these five therapeutic antibodies may effectively combat current and emerging SARS-CoV-2 variants, including Omicron BA.1 and BA.2. Therefore, the antibodies can potentially be used as universal neutralizing antibodies against SARS-CoV-2.

An efficient approach for SARS-CoV-2 monoclonal antibody production via modified mRNA-LNP immunization.

Throughout the COVID-19 pandemic, many prophylactic and therapeutic drugs have been evaluated and introduced. Among these treatments, monoclonal antibodies (mAbs) that bind to and neutralize SARS-CoV-2 virus have been applied as complementary and alternative treatments to vaccines. Although different methodologies have been utilized to produce mAbs, traditional hybridoma fusion technology is still commonly used for this purpose due to its unmatched performance record. In this study, we coupled the hybridoma fusion strategy with mRNA-lipid nanoparticle (LNP) immunization. This time-saving approach can circumvent biological and technical hurdles, such as difficult-to-express membrane proteins, antigen instability, and the lack of posttranslational modifications on recombinant antigens. We used mRNA-LNP immunization and hybridoma fusion technology to generate mAbs against the receptor binding domain (RBD) of SARS-CoV-2 spike (S) protein. Compared with traditional protein-based immunization approaches, inoculation of mice with RBD mRNA-LNP induced higher titers of serum antibodies and markedly increased serum neutralizing activity. The mAbs we obtained can bind to SARS-CoV-2 RBDs from several variants. Notably, RBD-mAb-3 displayed particularly high binding affinities and neutralizing potencies against both Alpha and Delta variants. In addition to introducing specific mAbs against SARS-CoV-2, our data generally demonstrate that mRNA-LNP immunization may be useful to quickly generate highly functional mAbs against emerging infectious diseases.

Pentadecapeptide BPC 157 efficiently reduces radiation-induced liver injury and lipid accumulation through Kruppel-like factor 4 upregulation both in vivo and in vitro.

AIMS: Radiation-induced liver disease (RILD) is the major complication for cancer patients after radiation therapy. We investigated the protective effects of BPC 157 peptide in reducing RILD. MATERIALS AND METHODS: Mice were irradiated with a single dose of 12 Gy to induce acute liver injury with or without oral BPC 157. Plasma levels of AST and ALT were determined. In vitro rat liver clone 9 cells and in vivo liver tissues were harvested for MTT assay, TUNEL assay, lipid staining, polypoid cell counts, Western blotting of caspase-3, PCNA, KLF-4 and HIF-2α, and immunocytochemistry for PCNA, KLF-4 and HIF-2α. SiRNAs were used to knockdown KLF-4. KEY FINDINGS: BPC 157 was firstly demonstrated to reduce RILD by decreasing plasma levels of AST and ALT, and inhibiting hydropic degeneration of liver. BPC 157 significantly decreased radiation-induced cell apoptosis, increased PCNA expression, promoted the expression of KLF4, decreased the radiation-induced hepatic lipid accumulation and HIF-2α expression both in mice liver and in clone 9 liver cells. The knockdown of KLF4 abolished the protective effect of BPC 157 on radiation-induced apoptosis and lipid accumulation in clone 9 liver cells, indicating that the protective effect of BPC 157 was mediated by KLF4 in liver cells. SIGNIFICANCE: The present study provided a good model for molecular mechanism underlying the acute RILD. BPC 157, as a stable pentadecapeptide that can be chemically synthesized and purified easily for research, together with its in vivo markedly protective effect made it worth of being investigated for future clinical application for RILD.