IgE and non-IgE food allergy: A review of immunological mechanisms.

Background: Food allergic (FA) conditions have been classified as immunoglobulin E (IgE) and non-IgE-mediated reactions that affect as many as 8% of young children and 2% of adults in Western countries, and their prevalence seems to be rising. Although the immunologic basis of IgE-mediated FA is well established, the mechanisms that govern non-IgE-mediated FA are not well understood and are marked by a paucity of comprehensive insights. Objective: The purpose of the present report is to examine the current classification and epidemiology of non-IgE-mediated FA, the latest immunologic mechanisms that underlie the three most commonly cited non-IgE FA conditions, viz., eosinophilic esophagitis, food protein-induced enterocolitis, and food protein-induced allergic proctocolitis, and explore what allergist/immunologists in practice should be aware of with regard to the condition. Methods: An extensive research was conducted in medical literature data bases by applying terms such as FA, non-IgE allergy, tolerance, unresponsiveness, cytokines, CD4+ T helper cell pathways, and key cytokine pathways involved in FA. Results: Current evidence now supports the view that immune dysregulation and cytokine-induced inflammation are the fundamental bases for both IgE- and non-IgE-mediated FA. The existing non-IgE-related FA literature is mostly characterized by a relative dearth of mechanistic information in contrast to IgE-mediated FA, in which the immunologic underpinnings as a T helper type 2 directed entity are well established. Although the need for future methodologic research and adherence to rigorous scientific protocols is essential, it is also necessary to acknowledge past contributions that have given much to our understanding of the condition. In the present report, a novel signature cytokine-based classification of IgE-mediated and non-IgE-mediated allergy is proposed that may offer a novel template for future research in the field of non-IgE-mediated FA. Conclusion: The present report provides an overview of the current classification and frequency of IgE- and non-IgE-mediated FAs, and offers insights and potential solutions to address lingering questions, particularly when concerning the latest immunologic mechanisms that underlie the pathogenesis of non-IgE-mediated FA. Although some progress has been made in recent years toward making diagnostic and treatment options available for these conditions, there still remain many lingering questions and concerns to be addressed, which can be fully understood by future research.

Long COVID diagnostic with differentiation from chronic lyme disease using machine learning and cytokine hubs.

The absence of a long COVID (LC) or post-acute sequelae of COVID-19 (PASC) diagnostic has profound implications for research and potential therapeutics given the lack of specificity with symptom-based identification of LC and the overlap of symptoms with other chronic inflammatory conditions. Here, we report a machine-learning approach to LC/PASC diagnosis on 347 individuals using cytokine hubs that are also capable of differentiating LC from chronic lyme disease (CLD). We derived decision tree, random forest, and gradient-boosting machine (GBM) classifiers and compared their diagnostic capabilities on a dataset partitioned into training (178 individuals) and evaluation (45 individuals) sets. The GBM model generated 89% sensitivity and 96% specificity for LC with no evidence of overfitting. We tested the GBM on an additional random dataset (106 LC/PASC and 18 Lyme), resulting in high sensitivity (97%) and specificity (90%) for LC. We constructed a Lyme Index confirmatory algorithm to discriminate LC and CLD.

Addressing global health disparities in the management of RSV infection in infants and children: Strategies for preventing bronchiolitis and post-bronchiolitis recurrent wheezing.

Background: The topic of equitable access to health care and its impact on exacerbating worldwide inequities in child health not only strikes at the heart of our health-care delivery systems but also deeply resonates with our collective social consciences. Nowhere is this better seen on a global scale than in the burden of illness caused by respiratory syncytial virus (RSV) infection, which extracts the most severe morbidity and mortality in infants and children in low- and middle-income countries (LMIC). This report addresses global health disparities that exist in the management of RSV infection in infants and children, and offers strategies for preventing bronchiolitis and postbronchiolitis recurrent wheezing in LMICs. Methods: A systematic literature review was conducted across the PubMed data bases of RSV infection and the socioeconomic impact of bronchiolitis and postbronchiolitis recurrent wheezing in LMICs. Results: The results of the present study address the many issues that deal with the question if prevention of RSV bronchiolitis can mitigate recurrent wheezing episodes and links RSV risks, downstream effects, prevention, malnutrition, and socioeconomic restraints of developing countries with a call for possible global action. Conclusion: The present study stresses the importance of considering the linkage between malnutrition and disease susceptibility because of the known relationships between undernutrition and greater vulnerability to infectious diseases, including RSV infection. These complex interactions between infectious disease and undernutrition also raise issues on the longer-term sequelae of postbronchiolitis recurrent wheezing. This prompts a discussion on whether industrialized countries should prioritize the provision of newly developed monoclonal antibodies and RSV vaccines to LMICs or whether vital nutritional needs should be a first focus. The resolution of these issues will require research and greater international discourse.

The Long Road of Long COVID: Specific Considerations for the Allergist/Immunologist.

Long COVID (coronavirus disease 2019) syndrome, also known as post-acute sequelae of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, is a new disorder that can develop after an acute infection with the SARS-CoV-2 virus. The condition is characterized by multiorgan system involvement with a wide range of symptoms that can vary in severity from mild to debilitating. Some of the common symptoms associated with long COVID syndrome include cardiovascular issues such as heart palpitations and chest pain; thrombotic events (eg, blood clotting disorders); metabolic problems (eg, type 2 diabetes); dysautonomia; paroxysmal orthostatic tachycardia syndrome; myalgic encephalomyelitis/chronic fatigue syndrome; reactivation of the Epstein-Barr virus; the presence of autoantibodies; chronic spontaneous urticaria (hives); and connective tissue diseases. Whereas long COVID syndrome can affect individuals from various backgrounds, certain populations may be at higher risk such as individuals of Hispanic and Latino heritage, as well as those with low socioeconomic status, although approximately one-third of affected patients have no known risk factors or preexisting conditions. Many survivors of COVID-19 struggle with multiple symptoms, increased disability, reduced function, and poor quality of life. Whereas vaccination has been the most significant intervention able to decrease the severity of acute SARS-Cov2 infection and curtail deaths, limited data are available related to its modulating effect on long COVID necessitating the need for further investigation. Furthermore, several inflammatory pathways have been proposed for the pathogenesis of long COVID that are the targets for ongoing clinical studies evaluating novel pharmacological agents. The purpose of the present report is to review the many factors associated with long COVID with a focus on those aspects that have relevance to the allergist-immunologist.

The PANDAS/PANS disorders. Is it time for more allergist-immunologists to get involved?

Background: The pediatric autoimmune neurologic disorders associated with streptococcal infections (PANDAS) comprise a group of patients who, after infection with group A ß-hemolytic streptococci (GAS), exhibit a spectrum of neuropsychiatric symptoms that include obsessive thoughts, compulsive behaviors, tics, hyperactivity, inattention, and mild choreiform movements. More recently, a group of patients with a symptom complex similar to PANDAS without evidence of streptococcal etiology was given the acronym pediatric acute-onset neuropsychiatric syndrome (PANS). Despite more than several decades of study and increasing numbers of patients being identified with PANDAS and PANS, there are ongoing controversies, which range from disagreements about specific pathogenetic mechanisms to whether these entities actually exist. Objective: The purpose of this report was to examine the current body of evidence that deals with the relationship(s) of immunologic host responses to infection and putative immunologic mechanisms involved in the pathogenesis of these disorders, to evaluate the effectiveness of anti-inflammatory and immunomodulatory therapies with intravenous immunoglobulin (IVIG), and to consider the extent to which allergist/immunologists might be involved in their management. Methods: An extensive literature review was conducted in medical literature data bases by applying terms such as PANDAS, PAN, autoimmune encephalitis, neuroinflammation, and autoimmune obsessive-compulsive disorders. Results: PANDAS and its later iterative form, PANS, continue to challenge clinicians, patients, and their families. Although the precise reason why these disorders develop remains unknown, both are considered to have an autoimmune basis related to the production of antibodies directed at antigens of the putative causative infectious disease agents that are cross-reactive with antigenic epitopes on selected brain nuclei, which lead to the neuroinflammatory sequelae responsible for the neuropsychiatric symptoms of these conditions, a phenomenon referred to as molecular mimicry. Conclusion: The PANDAS/PANS disorders are a continuing burden for growing numbers of patients, health-care providers, and the global health-care systems, and are a particular challenge for the allergist/immunologist who is increasingly being called upon for their management. Because of the importance of immunologic factors in the pathogenesis and treatment of these conditions with anti-inflammatory and immune-modulating treatments, the allergist/immunologist is well poised to offer consultative care.

The 80th anniversary of Annals of Allergy, Asthma & Immunology (1943-2023).

The year 2023 marks the 80th year of publication of Annals of Allergy, Asthma & Immunology. To celebrate this important milestone, we look back on the history of the journal from its inception to the present day. This special article explores the rationale and people involved in creating the journal and highlights major advances in Annals history. Our celebration of Annals' 80th year of publication concludes with a glimpse into the potential future of Annals.

The third pandemic: The respiratory syncytial virus landscape and specific considerations for the allergist/immunologist.

Background: Since its initial identification in 1956, respiratory syncytial virus (RSV) has been the second most common cause of mortality in infants <6 months of age and a major cause of morbidity and mortality associated with lower respiratory tract infection (LRTI) in older adults (ages >60 years) worldwide. Of particular interest to the allergist/immunologist is a growing body of evidence that suggests an association between LRTI caused by RSV in infants with later-life development of asthma, wheezing, or impaired lung function in adults. Efforts to develop a RSV vaccine have been thwarted for >70 years by the occurrence of enhanced respiratory disease (ERD), an adverse RSV vaccine reaction, in the 1960s, in which more-severe illness occurred on natural infection after vaccination of infants who were RSV naive and with a formalin-inactivated RSV vaccine. Recent advances in knowledge of the structural biology of the RSV surface fusion glycoprotein, however, have revolutionized RSV vaccine development for preventive interventions and have offered, at last, the hope of an effective and safe vaccine for the prevention of RSV disease. Objective: The purpose of this report was to examine the current evidence that supports the epidemiology, disease manifestations, molecular biology, treatments, and new vaccine development of RSV vaccines. Results: The host-immune response to RSV infection is carried out by two distinct but overlapping universes of mucosal and systemic immune systems in which a balanced set of B- and T-cell responses are involved in protective immunity that includes the mucosal immune system in which immunoglobulin A (IgA) prevails and the systemic immune system in which IgG neutralizing antibody predominates. The key to developing an effective vaccine is now thought to be linked to the availability of a stabilized prefusion F protein in the immunizing vaccine, which can perform a dual function of a balanced mucosal and/or systemic immune response as well as an effective antibody specifically directed to critical epitopes on the requisite prefusion F protein. Conclusion: The unfortunate manifestation of RSV ERD that occurred in the 1960s has led to a better understanding of the structural biology of the RSV surface fusion glycoprotein and has provided a basis for the development of more effective and safer RSV vaccines and monoclonal antibody preparations for immunoprophylaxis of the dread effects of RSV disease. There are now a large number of clinical trials in progress that are evaluating these products, which include recombinant vector, subunit, particle-based, live-attenuated, chimeric, and nucleic acid vaccines; and monoclonal antibodies. This article gives an overview of the many aspects of RSV disease and development of virus (RSV) vaccines of particular interest to the allergist/immunologist.