Systemic immunosuppression in times of COVID-19: Do we need to rethink our standards?

An Outbreak of Acute Hemorrhagic Conjunctivitis Caused by Coxsackievirus A24 in Eastern Uttar Pradesh, India 2023

INTRODUCTION

Acute hemorrhagic conjunctivitis (AHC) outbreaks are caused mostly by viruses. During July-August 2023, there was a sudden spike in acute hemorrhage conjunctivitis cases in Eastern Uttar Pradesh, India. To identify the etiological and gain molecular epidemiology of the agent, the study was conducted.

METHODOLOGY

Conjunctival swabs were collected from patients (n = 128) with presumed acute hemorrhage conjunctivitis visiting two tertiary care hospitals.

RESULTS

Enteroviruses infection was identified in 96 (75%) patients. In these patients, coxsackievirus A24 (CV-A24) infection was further confirmed by targeting the genetic regions of 3C protease and VP1. Furthermore, the study established the outbreak was caused by the genotype IV of CV-A24 with the highest genetic similarity with CV-A24 reported from Northeast India, China, and Pakistan circulating during the same period. The comparison of our study sequences with earlier Indian outbreak strains (2007) revealed four amino acid substitutions at the 3C region ("S21N," "V30I," "S66I," and "V75I") and three non-synonymous mutations at the VP1 region ("L16I," "P21S," and "N301D").

CONCLUSION

The study findings revealed that the AHC outbreak was caused by genotype IV of CV-A24 in this region. Molecular identification accompanied by phylogenetic analysis will be useful in studying the enterovirus epidemiology associated with AHC outbreaks.

Harnessing Immunomodulatory Polymers for Treatment of Autoimmunity, Allergy, and Transplant Rejection

Autoimmunity, allergy, and transplant rejection are a collection of chronic diseases that are currently incurable, drastically decrease patient quality of life, and consume considerable health care resources. Underlying each of these diseases is a dysregulated immune system that results in the mounting of an inflammatory response against self or an innocuous antigen. As a consequence, afflicted patients are required to adhere to lifelong regimens of multiple immunomodulatory drugs to control disease and reclaim agency. Unfortunately, current immunomodulatory drugs are associated with a myriad of side effects and adverse events, such as increased risk of cancer and increased risk of serious infection, which negatively impacts patient adherence rates and quality of life. The field of immunoengineering is a new discipline that aims to harness endogenous biological pathways to thwart disease and minimize side effects using novel biomaterial-based strategies. We highlight and discuss polymeric micro/nanoparticles with inherent immunomodulatory properties that are currently under investigation in biomaterial-based therapies for treatment of autoimmunity, allergy, and transplant rejection.

Oxidative Stress and Phototherapy in Atopic Dermatitis: Mechanisms, Role, and Future Perspectives

Atopic dermatitis is a chronic inflammatory skin disease in which the overproduction of reactive oxygen species plays a pivotal role in the pathogenesis and persistence of inflammatory lesions. Phototherapy represents one of the most used therapeutic options, with benefits in the clinical picture. Studies have demonstrated the immunomodulatory effect of phototherapy and its role in reducing molecule hallmarks of oxidative stress. In this review, we report the data present in literature dealing with the main signaling molecular pathways involved in oxidative stress after phototherapy to target atopic dermatitis-affected cells. Since oxidative stress plays a pivotal role in the pathogenesis of atopic dermatitis and its flare-up, new research lines could be opened to study new drugs that act on this mechanism, perhaps in concert with phototherapy.

Interdependencies of cellular and humoral immune responses in heterologous and homologous SARS-CoV-2 vaccination

Background

Homologous and heterologous SARS‐CoV‐2 vaccinations yield different spike protein‐directed humoral and cellular immune responses. This study aimed to explore their currently unknown interdependencies.

Methods

COV‐ADAPT is a prospective, observational cohort study of 417 healthcare workers who received vaccination with homologous ChAdOx1 nCoV‐19, homologous BNT162b2 or with heterologous ChAdOx1 nCoV‐19/BNT162b2. We assessed humoral (anti‐spike‐RBD‐IgG, neutralizing antibodies, and avidity) and cellular (spike‐induced T‐cell interferon‐γ release) immune responses in blood samples up to 2 weeks before (T1) and 2–12 weeks following secondary immunization (T2).

Results

Initial vaccination with ChAdOx1 nCoV‐19 resulted in lower anti‐spike‐RBD‐IgG compared with BNT162b2 (70 ± 114 vs. 226 ± 279 BAU/ml, p < .01) at T1. Booster vaccination with BNT162b2 proved superior to ChAdOx1 nCoV‐19 at T2 (anti‐spike‐RBD‐IgG: ChAdOx1 nCoV‐19/BNT162b2 2387 ± 1627 and homologous BNT162b2 3202 ± 2184 vs. homologous ChAdOx1 nCoV‐19 413 ± 461 BAU/ml, both p < .001; spike‐induced T‐cell interferon‐γ release: ChAdOx1 nCoV‐19/BNT162b2 5069 ± 6733 and homologous BNT162b2 4880 ± 7570 vs. homologous ChAdOx1 nCoV‐19 1152 ± 2243 mIU/ml, both p < .001). No significant differences were detected between BNT162b2‐boostered groups at T2. For ChAdOx1 nCoV‐19, no booster effect on T‐cell activation could be observed. We found associations between anti‐spike‐RBD‐IgG levels (ChAdOx1 nCoV‐19/BNT162b2 and homologous BNT162b2) and T‐cell responses (homologous ChAdOx1 nCoV‐19 and ChAdOx1 nCoV‐19/BNT162b2) from T1 to T2. Additionally, anti‐spike‐RBD‐IgG and T‐cell response were linked at both time points (all groups combined). All regimes yielded neutralizing antibodies and increased antibody avidity at T2.

Conclusions

Interdependencies between humoral and cellular immune responses differ between common SARS‐CoV‐2 vaccination regimes. T‐cell activation is unlikely to compensate for poor humoral responses.

Biomaterial-based immunotherapeutic strategies for rheumatoid arthritis

Rheumatoid arthritis (RA) is an extremely painful autoimmune disease characterized by chronic joint inflammation leading to the erosion of adjacent cartilage and bone. Rheumatoid arthritis pathology is primarily driven by inappropriate infiltration and activation of immune cells within the synovium of the joint. There is no cure for RA. As such, manifestation of symptoms entails lifelong management via various therapies that aim to generally dampen the immune system or impede the function of immune mediators. However, these treatment strategies lead to adverse effects such as toxicity, general immunosuppression, and increased risk of infection. In pursuit of safer and more efficacious therapies, many emerging biomaterial-based strategies are being developed to improve payload delivery, specific targeting, and dose efficacy, and to mitigate adverse reactions and toxicity. In this review, we highlight biomaterial-based approaches that are currently under investigation to circumvent the limitations of conventional RA treatments.

Transitioning From Immunosuppressants to Dupilumab in Pediatric Atopic Dermatitis

Dupilumab has recently been approved by the Food and Drug Administration for use for treatment of moderate to severe atopic dermatitis in children aged 6 to 11 years. It presents a novel treatment option with a favorable safety profile for patients who are currently reliant on immunosuppressants, including cyclosporine A, methotrexate, and mycophenolate mofetil. Particularly during the current COVID-19 pandemic, immunosuppression should be avoided to retain intrinsic antiviral immunity. Transitioning to dupilumab should be executed strategically-tapering immunosuppressants and minimizing risk of flare by overlapping with the biologic. Herein, we use results of outcome measurements from LIBERTY AD ADOL and LIBERTY AD PEDS trials of dupilumab in adolescents aged 12 to 18 years and children aged 6 to 11 years, respectively, to propose a schematic for an 8-week transition between medications.

Downregulation of CD45 Signaling in COVID-19 Patients Is Reversed by C24D, a Novel CD45 Targeting Peptide

CD45, the predominant transmembrane tyrosine phosphatase in leukocytes, is required for the efficient induction of T cell receptor signaling and activation. We recently reported that the CD45-intracellular signals in peripheral blood mononuclear cells (PBMCs) of triple negative breast cancer (TNBC) patients are inhibited. We also reported that C24D, an immune modulating therapeutic peptide, binds to CD45 on immune-suppressed cells and resets the functionality of the immune system via the CD45 signaling pathway. Various studies have demonstrated that also viruses can interfere with the functions of CD45 and that patients with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) are immune-suppressed. Given the similarity between the role of CD45 in viral immune suppression and our findings on TNBC, we hypothesized that the C24D peptide may have a similar "immune-resetting" effect on PBMCs from COVID-19 patients as it did on PBMCs from TNBC patients. We tested this hypothesis by comparing the CD45/TCR intracellular signaling in PBMCs from ten COVID-19 patients vs. PBMCs from ten healthy volunteers. Herein, we report our findings, demonstrating the immune reactivating effect of C24D via the phosphorylation of the tyrosine 505 and 394 in Lck, the tyrosine 493 in ZAP-70 and the tyrosine 172 in VAV-1 proteins in the CD45 signaling pathway. Despite the relatively small number of patients in this report, the results demonstrate that C24D rescued CD45 signaling. Given the central role played by CD45 in the immune system, we suggest CD45 as a potential therapeutic target.

Clinical Profile of COVID-19 Patients Presenting with Uveitis - A Short Case Series

Purpose

To present the clinical features of anterior, intermediate and posterior uveitis in patients with COVID-19 and to increase the awareness of the treating physicians to refer patients with COVID-19 who have eye symptoms for ophthalmic exam, in order to diagnose as early as possible and prevent vision-threatening complications.

Methods

Retrospective observational case reports.

Results

We report three cases of COVID-19 patients who developed uveitis during or after the course of their sickness with COVID-19. All patients underwent a detailed eye examination, relevant history and investigations did not prove any other cause of uveitis.

Conclusion

This report presents novel data on the course of subjects with uveitis during the COVID-19 pandemic. Intermediate and posterior uveitis warrant further evaluation with differential diagnosis supported by laboratory tests due to the association with systemic diseases and risk of permanent vision loss. Iridocyclitis, intermediate, and posterior uveitis treatment should be guided by ophthalmologists, particularly uveitis specialists, when possible.