Controversial role of neutrophilic granulocytes in the immunopathogenesis of COVID-19: correlation with imbalance of pro-inflammatory neutrophil-associated cytokines and interferon alpha deficiency.

Neutrophilic granulocytes (NG) are the main drivers of pathological inflammation in COVID-19. Objective. To specify the mechanisms of immunopathogenesis of COVID-19 based on a comparative immunological study of the number and phenotype of CD16+SD62L+CD11b+CD63- and CD16+SD62L+CD11b+CD63+ subsets with an assessment of their effector functions against changing profile of NG-associated cytokines IL-8, IL-18, IL-17A, VEGF-A, IFNalpha, and IFNgamma. Patients and methods. In patients with moderate-to-severe and severe COVID-19, we determined IL-1beta, TNFalpha, IL-6, IL-8, IL-18, IL-17A, VEGF-A, IFNalpha, and IFNgamma (ELISA), the phenotype of CD16+SD62L+CD11b+CD63- and CD16+SD62L+CD11b+CD63+ subsets, NF-kappaB-NG (CYTOMICS FC500), phagocytically active NG (%), neutrophil extracellular traps (NETs), NG in apoptosis, and the activity of NADPH oxidase. Results. In COVID-19 against the background of IFNalpha and IFNgamma production blockade and high levels of NG-associated IL-8, IL-18, IL-17A, VEGF-A, a reduction in the number of mature and functionally active CD16brightSD62LbrightCD11bbrightCD63-NG subsets was revealed, as well as an increase in the number of CD16dimSD62LdimSD11bbrightCD63-NG subsets with an immunosuppressive phenotype and CD16brightSD62LbrightSD11bbrightCD63bright-NG subsets with high cytotoxic activity and ability to form NETs, a decrease in the percentage of phagocytically active NG and an increase in the activity of NADPH oxidase, NETs, and NG in apoptosis. Conclusion. IFNalpha deficiency provokes a hyperergic response of NG-associated cytokines, which leads to the formation of uncontrolled immune inflammation involving NG subsets with an immunosuppressive and cytotoxic phenotype, exacerbating the course of COVID-19. The use of recombinant IFNalpha-2b with antioxidants (Viferon) in the early stages of the disease can help to restore immune homeostasis, normalize the level of NG-associated cytokines, reduce NERTs, and achieve good clinical efficacy.Copyright © 2022, Dynasty Publishing House. All rights reserved.

Pharmacological Properties and Safe Use of 12 Medicinal Plant Species and Their Bioactive Compounds Affecting the Immune System

This paper presents raw plant materials and their characteristic compounds which may affect the immune system. Plant-derived agents in specific doses affect the body's non-specific, antigen-independent defense system. They have immunostimulatory effects on the entire immune regulatory system. They can enhance the immune response through various factors such as macrophages, leukocytes, and granulocytes, as well as through mediators released by the cellular immune system. This paper was inspired by the threats caused by the COVID-19 pandemic. The proper functioning of the immune system is important in limiting the effects of viral infection and restoring the normal functioning of the body. This paper also emphasizes the importance of the skillful use of plant immunostimulants by potential patients, but also by those who prescribe drugs. It is important not only to choose the right plant drug but above all to choose the correct dose and duration of treatment.

Controversial role of neutrophilic granulocytes in the immunopathogenesis of COVID-19: correlation with imbalance of pro-inflammatory neutrophil-associated cytokines and interferon alpha deficiency.

Neutrophilic granulocytes (NG) are the main drivers of pathological inflammation in COVID-19. Objective. To specify the mechanisms of immunopathogenesis of COVID-19 based on a comparative immunological study of the number and phenotype of CD16+SD62L+CD11b+CD63- and CD16+SD62L+CD11b+CD63+ subsets with an assessment of their effector functions against changing profile of NG-associated cytokines IL-8, IL-18, IL-17A, VEGF-A, IFNalpha, and IFNgamma. Patients and methods. In patients with moderate-to-severe and severe COVID-19, we determined IL-1beta, TNFalpha, IL-6, IL-8, IL-18, IL-17A, VEGF-A, IFNalpha, and IFNgamma (ELISA), the phenotype of CD16+SD62L+CD11b+CD63- and CD16+SD62L+CD11b+CD63+ subsets, NF-kappaB-NG (CYTOMICS FC500), phagocytically active NG (%), neutrophil extracellular traps (NETs), NG in apoptosis, and the activity of NADPH oxidase. Results. In COVID-19 against the background of IFNalpha and IFNgamma production blockade and high levels of NG-associated IL-8, IL-18, IL-17A, VEGF-A, a reduction in the number of mature and functionally active CD16brightSD62LbrightCD11bbrightCD63-NG subsets was revealed, as well as an increase in the number of CD16dimSD62LdimSD11bbrightCD63-NG subsets with an immunosuppressive phenotype and CD16brightSD62LbrightSD11bbrightCD63bright-NG subsets with high cytotoxic activity and ability to form NETs, a decrease in the percentage of phagocytically active NG and an increase in the activity of NADPH oxidase, NETs, and NG in apoptosis. Conclusion. IFNalpha deficiency provokes a hyperergic response of NG-associated cytokines, which leads to the formation of uncontrolled immune inflammation involving NG subsets with an immunosuppressive and cytotoxic phenotype, exacerbating the course of COVID-19. The use of recombinant IFNalpha-2b with antioxidants (Viferon) in the early stages of the disease can help to restore immune homeostasis, normalize the level of NG-associated cytokines, reduce NERTs, and achieve good clinical efficacy.Copyright © 2022, Dynasty Publishing House. All rights reserved.

THE ROLE OF NEUTROPHIL EXTRACELLULAR TRAPS (NETs) IN THE IMMUNOPATHOGENESIS OF SEVERE COVID-19: POTENTIAL IMMUNOTHERAPEUTIC STRATEGIES REGULATING NET FORMATION AND ACTIVITY.

The role of neutrophil granulocytes (NG) in the pathogenesis of COVID-19 is associated with the NG recruitment into inflammatory foci, activation of their functions and enhanced formation of neutrophil extracellular networks (NETs). In this review, we analyzed a large body of scientific literature devoted to the features of developing NETs, their role in the COVID-19 pathogenesis, a role in emerging immunothrombosis, vasculitis, acute respiratory distress syndrome, cytokine storm syndrome, and multi-organ lesions. Convincing data are presented clearly indicating about a profound role of NETs in the COVID-19 immunopathogenesis and associated severe complications resulting from intensified inflammation process, which is a key for the course of SARS-CoV-2 virus infection. The presented role of NGs and NETs, along with that of other immune system cells and pro-inflammatory cytokines, is extremely important in understanding development of overactive immune response in severe COVID-19. The scientific results obtained available now allow to identify an opportunity of regulatory effects on hyperactivated NGs, NETosis at various stages and on limiting a negative impact of pre-formed NETs on various tissues and organs. All the aforementioned data should help in creating new, specialized immunotherapy strategies designed to increase the odds of survival, reduce severity of clinical manifestations in COVID-19 patients as well as markedly reduce mortality rates. Currently, it is possible to use existing drugs, while a number of new drugs are being developed, the action of which can regulate NG quantity, positively affect NG functions and limit intensity of NETosis. Continuing research on the role of hyperactive NG and NETosis as well as understanding the mechanisms of regulating NET formation and restriction in severe COVID-19, apparently, are of high priority, because in the future the new data obtained could pave the basis for development of targeted approaches not only for immunotherapy aimed at limiting education and blocking negative effects already formed NETs in severe COVID-19, but also for immunotherapy, which could be used in combination treatment of other netopathies, primarily autoimmune diseases, auto-inflammatory syndromes, severe purulent-inflammatory processes, including bacterial sepsis and hematogenous osteomyelitis.Copyright © 2023 Saint Petersburg Pasteur Institute. All rights reserved.

Acute onset of eosinophil dermatitis after COVID-19-vaccination with BNT162b2.

In the current time, the question about possible side effects of the COVID-19 immunization has a high priority, especially because booster vaccinations are being discussed, making the occurrence of side effects more likely. In order to better understand the latter, the compilation of the side effects that have occurred is indispensable. Therefore, we report a new case from our dermatological university outpatient clinic at Hannover Medical School, which sheds light on a possible link between active immunization to prevent COVID-19 disease caused by SARS-CoV-2 and the role of eosinophilic granulocytes.Copyright ©2023 Dustri-Verlag Dr. K. Feistle.

Upregulation of coronavirus (MERS-CoV) receptor dipeptidyl peptodase 4 on camel leukocytes after bacterial stimulation in vitro

Middle East respiratory syndrome coronavirus (MERS-CoV) is an emerging zoonotic pathogen which causes high mortality rate in humans. Dromedary camels may play a central role in virus transmission to humans. Dipeptidyl peptidase-4 (DPP4), a transmembrane protein located on the cell surface of many epithelial and endothelial tissues was identified as the receptor for MERS-CoV. The current study investigated the possibility that bacterial stimulation of camel blood could affect the expression level of DPP4 on camel leukocyte subpopulation, which in turn may contribute to the higher susceptibility of camels with bacterial infection to MERS-CoV infection. DPP4 expression was evaluated by membrane immunofluorescence and flow cytometry. Stimulation of camel blood with the bacterial species S. aureus or E. coil resulted in the upregulation of DPPV on both monocytes and granulocytes, while S. agalactiae did not significantly modulate DPPV expression on either of the immune cells (p > 0.05). None of the bacterial species could induce a change in DPPV expression on lymphocytes from stimulated blood. Collectively, the present study showed an enhancing effect of bacterial stimulation on DPPV expression on camel monocytes and granulocytes.

Transcriptional dynamics of granulocytes in direct response to incubation with SARS-CoV-2.

Severe coronavirus disease 2019 (COVID-19) is characterized by acute respiratory distress syndrome and multiple organ dysfunction, in which the host immune response plays a pivotal role. Excessive neutrophil activation and subsequent superfluity of neutrophil extracellular traps (NETs) can lead to tissue damage, and several studies have shown the involvement of neutrophils in severe COVID-19. However, the detailed responses of each neutrophil subset to SARS-CoV-2 infection has not been fully described. To explore this issue, we incubated normal-density granulocytes (NDGs) and low-density granulocytes (LDGs) with different viral titers of SARS-CoV-2. NDGs form NETs with chromatin fibers in response to SARS-CoV-2, whereas LDGs incubated with SARS-CoV-2 display a distinct morphology with condensed nuclei and moderate transcriptional changes. Based on these transcriptional changes, we suggest that AGO2 possibly plays a role in LDG regulation in response to SARS-CoV-2.

Zymosan Particle-Induced Hemodynamic, Cytokine and Blood Cell Changes in Pigs: An Innate Immune Stimulation Model with Relevance to Cytokine Storm Syndrome and Severe COVID-19.

Hemodynamic disturbance, a rise in neutrophil-to-lymphocyte ratio (NLR) and release of inflammatory cytokines into blood, is a bad prognostic indicator in severe COVID-19 and other diseases involving cytokine storm syndrome (CSS). The purpose of this study was to explore if zymosan, a known stimulator of the innate immune system, could reproduce these changes in pigs. Pigs were instrumented for hemodynamic analysis and, after i.v. administration of zymosan, serial blood samples were taken to measure blood cell changes, cytokine gene transcription in PBMC and blood levels of inflammatory cytokines, using qPCR and ELISA. Zymosan bolus (0.1 mg/kg) elicited transient hemodynamic disturbance within minutes without detectable cytokine or blood cell changes. In contrast, infusion of 1 mg/kg zymosan triggered maximal pulmonary hypertension with tachycardia, lasting for 30 min. This was followed by a transient granulopenia and then, up to 6 h, major granulocytosis, resulting in a 3-4-fold increase in NLR. These changes were paralleled by massive transcription and/or rise in IL-6, TNF-alpha, CCL-2, CXCL-10, and IL-1RA in blood. There was significant correlation between lymphopenia and IL-6 gene expression. We conclude that the presented model may enable mechanistic studies on late-stage COVID-19 and CSS, as well as streamlined drug testing against these conditions.

Epidemiological and clinical characteristics of 140 patients with Delta COVID-19 in Gansu Province

OBJECTIVE: To analyze the differences of clinical characteristics, laboratory tests and imaging examinations in patients with Novel Coronavirus(SARS-COV-2)Delta variant infection in Gansu province, so as to provide reference for the prevention and treatment of SARS-COV-2. METHODS: The medical records, laboratory tests and imaging studies of 140 patients with SARS-COV-2 Delta variant infection admitted to Yantan Branch and Zhangye Second Hospital of Lanzhou Second People's Hospital from Oct. to Dec. 2021 in Gansu province were retrospectively analyzed. RESULTS: Among the 140 infected patients, 65 were males and 75 were females. The oldest was 87 years old, and the youngest was 1 year and 8 months, with an average age of(42.65+or-20.87) years old. Twenty percent of confirmed patients had fever. The mean duration of positive nucleic acid was 19.74 days. There were significant differences in the expression levels of serum amyloid A(SAA), interleukin-6(IL-6), C-reactive protein(CRP), basophil granulocytes(BAS) and lymphocyte(LYM) in patients with different types. Pulmonary lesions were found in 101 patients(72.14%) by imaging, and the proportion of abnormal lung imaging in mild, ordinary and severe patients accounted for 55.81%, 73.13% and 100% respectively. CONCLUSION: The majority of patients with COVID-19 Delta infection in Gansu province were mild and ordinary type. There were fewer fever patients. The main clinical manifestations were cough, expectoration and pharyngeal discomfort. Severe and critically ill patients are older and have more underlying diseases.

Myeloid Sarcoma Mimicking Dental Abscess in a Patient with Chronic Myeloid Leukemia: Diagnostic and Therapeutic Dilemma

Chronic myeloid leukemia (CML) is a hematologic malignancy that has significant improvement in its prognosis after the introduction of tyrosine kinase inhibitors. Transformation to accelerated phase or blast phase can happen. Myeloid sarcoma or chloroma is an uncommon extramedullary disease. It is very unusual for patients with CML to develop myeloid sarcoma. We report a young man with CML in the chronic phase who developed myeloid sarcoma. There were many difficulties in the diagnosis of myeloid sarcoma due to the simulation of other more common conditions like infections and other malignancies. In addition, there are treatment challenges because of lack of standardized treatment. The case shed light on this rare complication, the challenging diagnosis, and its implication in patients with CML.

COVID-19 patients share common, corticosteroid-independent features of impaired host immunity to pathogenic molds.

Patients suffering from coronavirus disease-2019 (COVID-19) are susceptible to deadly secondary fungal infections such as COVID-19-associated pulmonary aspergillosis and COVID-19-associated mucormycosis. Despite this clinical observation, direct experimental evidence for severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2)-driven alterations of antifungal immunity is scarce. Using an ex-vivo whole blood stimulation assay, we challenged blood from twelve COVID-19 patients with Aspergillus fumigatus and Rhizopus arrhizus antigens and studied the expression of activation, maturation, and exhaustion markers, as well as cytokine secretion. Compared to healthy controls, T-helper cells from COVID-19 patients displayed increased expression levels of the exhaustion marker PD-1 and weakened A. fumigatus- and R. arrhizus-induced activation. While baseline secretion of proinflammatory cytokines was massively elevated, whole blood from COVID-19 patients elicited diminished release of T-cellular (e.g., IFN-γ, IL-2) and innate immune cell-derived (e.g., CXCL9, CXCL10) cytokines in response to A. fumigatus and R. arrhizus antigens. Additionally, samples from COVID-19 patients showed deficient granulocyte activation by mold antigens and reduced fungal killing capacity of neutrophils. These features of weakened anti-mold immune responses were largely decoupled from COVID-19 severity, the time elapsed since diagnosis of COVID-19, and recent corticosteroid uptake, suggesting that impaired anti-mold defense is a common denominator of the underlying SARS-CoV-2 infection. Taken together, these results expand our understanding of the immune predisposition to post-viral mold infections and could inform future studies of immunotherapeutic strategies to prevent and treat fungal superinfections in COVID-19 patients.

The relationship between immature granulocyte count and mortality in ARDS Due to COVID-19.

Background: Acute phase reactants and inflammation biomarkers such as ferritin, procalcitonin, C-reactive protein (CRP), and complete blood count parameters (White blood cell, platelet count) are usually used to evaluate and monitor the disease severity and treatment response of systemic inflammatory diseases. In addition to these parameters, Immature granulocytes (IG) that increase during systemic infection, hematological malignancy, and drug treatments (such as chemotherapy and glucocorticoids) are important parameters for evaluating systemic inflammation. The sensitivity and specificity of IG are as high as the abovementioned inflammatory biomarkers for monitoring disease severity and treatment response. Aim: The aim of the study is to evaluate the relationship between IG count and the need for mechanical ventilation and mortality in patients hospitalized in the intensive care unit (ICU) due to coronavirus disease 2019 (COVID-19). Patients and Methods: The medical records of the 401 patients who were followed up in the ICU due to COVID-19-related acute respiratory distress syndrome between October 2020 and February 2021 were retrospectively reviewed. On the day of admission to the ICU complete blood count (CBC), arterial blood gas analysis, coagulation parameters (fibrinogen, D-dimer) are recorded. CRP, procalcitonin, and ferritin levels are also recorded at the day of admission. During the follow-up period, the survival status and mechanical ventilation status of the patients were recorded and the relation between IG count and these parameters was evaluated. Results: The mean IG at the admission was 0.2 ± 0.4 109/L. The IG level of the intubated patients at the time of intubation was 0.3 ± 0.5 109/L. There was a significant positive correlation between mortality and IG levels at admission and at the time of intubation (IG admission; P = 0.001, r = 0.347 and IG at intubation; P = 0.001, r = 0.228). Conclusion: IG levels in CBC data could be a potential practical biomarker. This issue requires further research and the development of therapies targeting IG cells is needed.

Differential Regulation of CD45 Expression on Granulocytes, Lymphocytes, and Monocytes in COVID-19.

CD45 is a transmembrane glycoprotein and protein tyrosine phosphatase expressed on the surface of all nucleated hematopoietic cells. While there is increasing evidence demonstrating the involvement of CD45 in immune system regulation, no information on CD45 expression in inflammation and sepsis is currently available. Therefore, we determined the CD45 surface expression on granulocytes, lymphocytes, and monocytes in patients with COVID-19 and healthy volunteers in both absence and presence of lipopolysaccharide (LPS). Following approval by the local ethics committee, whole blood samples were obtained from patients with COVID-19 infection on day 1 of hospital admission and healthy volunteers. Samples were incubated in absence and presence of LPS and CD45 was measured in granulocytes, lymphocytes, and monocytes using flow cytometry. In comparison with healthy individuals, COVID-19 patients showed an increased CD45 expression on the surface of granulocytes (+35%, p < 0.02) and lymphocytes (+39%, p < 0.0001), but a reduced CD45 expression on monocytes (-35%, p < 0.0001). LPS incubation of whole blood from healthy individuals increased the CD45 expression on granulocytes (+430%, p < 0.0001), lymphocytes (+32%, p = 0.0012), and monocytes (+36%, p = 0.0005), respectively. LPS incubation of whole blood samples from COVID-19 patients increased the CD45 expression on granulocytes and monocytes, and decreased the CD45 expression on lymphocytes. In conclusion, CD45 expression on leucocytes is altered: (1) in COVID-19 patients, and (2) in in vitro endotoxemia in a complex cell-specific way, thus representing a new immunoregulatory mechanism.

Immature granulocytes: Innovative biomarker for SARS-CoV-2 infection

Immature granulocytes (IGs) include metamyelocytes, myelocytes and promyelocytes, and are the precursors of neutrophils. Increased IG counts found in peripheral blood indicate an enhanced bone marrow activity. In addition, IGs have been evaluated in numerous clinical conditions, such as severe acute pancreatitis, systemic inflammatory response syndrome and infectious complications following open-heart surgery under cardiopulmonary bypass. Neutrophils are considered to play a crucial role in the host defense during bacterial and fungal infections, and are involved in the antiviral immune response. Numerous studies have reported the role of neutrophils in coronavirus disease 2019 (COVID-19) infection, concluding that the percentage of neutrophils may be a predictor of the severity of COVID-19 infection. There has been limited research regarding the role of neutrophil precursors in viral infections, including severe acute respiratory syndrome coronavirus 2 infection. The present thus aimed to evaluate the role of the IG count in patients hospitalized due to COVID-19 infection. The patients were predominantly infected with the alpha variant and were all unvaccinated. The IG count was measured and was found to be associated with disease severity, with patient outcomes, with the duration of hospitalization and with the development of complications. The IG count was a significantly associated with the severity of COVID-19 infection, with greater IG count values being detected in severe and critical cases. In addition, greater IG count values were associated with a longer duration of hospitalization. Furthermore, the IG count was found to be an independent prognostic biomarker of intubation and mortality in patients with COVID-19, according to multivariate logistic regression analysis, including age, the male sex and the presence of comorbidities as confounders. [ FROM AUTHOR] Copyright of Molecular Medicine Reports is the property of Spandidos Publications UK Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)

Immature granulocytes: Innovative biomarker for SARS­CoV­2 infection.

Immature granulocytes (IGs) include metamyelocytes, myelocytes and promyelocytes, and are the precursors of neutrophils. Increased IG counts found in peripheral blood indicate an enhanced bone marrow activity. In addition, IGs have been evaluated in numerous clinical conditions, such as severe acute pancreatitis, systemic inflammatory response syndrome and infectious complications following open­heart surgery under cardiopulmonary bypass. Neutrophils are considered to play a crucial role in the host defense during bacterial and fungal infections, and are involved in the antiviral immune response. Numerous studies have reported the role of neutrophils in coronavirus disease 2019 (COVID­19) infection, concluding that the percentage of neutrophils may be a predictor of the severity of COVID­19 infection. There has been limited research regarding the role of neutrophil precursors in viral infections, including severe acute respiratory syndrome coronavirus 2 infection. The present thus aimed to evaluate the role of the IG count in patients hospitalized due to COVID­19 infection. The patients were predominantly infected with the alpha variant and were all unvaccinated. The IG count was measured and was found to be associated with disease severity, with patient outcomes, with the duration of hospitalization and with the development of complications. The IG count was a significantly associated with the severity of COVID­19 infection, with greater IG count values being detected in severe and critical cases. In addition, greater IG count values were associated with a longer duration of hospitalization. Furthermore, the IG count was found to be an independent prognostic biomarker of intubation and mortality in patients with COVID­19, according to multivariate logistic regression analysis, including age, the male sex and the presence of comorbidities as confounders.

Case report on post COVID manifestations

Introduction: Corona virus disease 2019 (COVID-19) is an infectious breathing sickness because of the corona virus 2. (SARS-CoV-2). the first recognised case become observed in Wuhan, China, in December of this year. The sickness has for the reason that spread round the arena, ensuing in a virulent disease. A giant pro-coagulant nation in addition to an inflammatory cytokine hurricane, comparable to what is seen in macrophages. As of April 20th, 2020, COVID-19 (excessive acute respiration syndrome corona virus 2 [SARSCoV2] or 2019nCoV) were detected in about 2. Four million persons round the world. the first case of COVID-19 (extreme acute respiration syndrome corona virus 2 [SARSCoV2] or 2019nCoV) turned into located in Wuhan, China. Because of its excessive infectivity, low virulence, and asymptomatic transmission, it is a completely contagious disease. Clinical findings: A 62-year-old male patient was admitted to AVBRH with complaints of vomiting, loss of appetite, nausea, weakness, and muscle cramps, He had hypertension, diabetes mellitus. Diagnostic Evaluation: HB-11.1 gm %, MCHC-33.5, MCV-86.9, MCH-29.1, MCHC-33.5, MCHC-33.5, MCHC-33.5, MCHC-33.5, MCHC-33.5, MCHC-33.5, MCHC-33.5, 3.83 total rbc count, HCT-33.2, RDW-14.6, total wbc count-11400Total platelet count was 0.83, Monocytes were 4 and Granulocytes were 85, 9.1 grammes of total protein (PL REPEAT) Therapeutic Intervention: Inj Emset 4 mg, Inj Metro 100 mg BD, Inj Rein 40 mg OD, Inj pan 40 mg BD, Inj cetri 10 gm BD, Inj perinorm TDS Outcome: The medication for vomiting, diabetes, and hypertension, as well as fever and cough, has begun. Due to the patient's weight, physiotherapy was prescribed.

Exploiting Inhibitory Siglecs to Combat Food Allergies

During the fourth year of this award, we have continued to generate important data related to targeting of CD22 on B cells and CD33 on mast cells to abrogate food allergies. Unfortunately, the COVID-19 pandemic shut down our labs in March 2020 for several months, causing some delays in our work. With that said, we have still produced new data and are now back in the labs on a regular basis to carry out additional experiments. For the CD22 project, we have now developed a humanized mouse model using NSG mice lacking mouse B and T cells, transfused with human PBMCs. These mice make human IgG against peanut allergens upon exposure to peanut and in pilot experiments, we were successful in stopping this IgG production by use of Ah1 STALs. We have also prepared mouse CD22L Ah1, Ah2, Ah3, and Ah6 for use in our conferred memory model to block IgE production to all major allergens. In terms of targeting CD33 in this past year, we have developed a novel approach by conjugating human CD33L directly to anti-human IgE, without the use of liposomes for scaffolding. This molecule is effective in inducing tolerance in humanized mice. Overall, our results move us closer to translating our STALs platform into human studies by focusing now on the use of humanized mouse models and human CD22 and CD33 ligands in our systems. Finally, we have applied for an Expansion Award for this project.