COVID-19: immunopathology, pathophysiological mechanisms, and treatment options

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), continues to spread globally despite the worldwide implementation of preventive measures to combat the disease. Although most COVID-19 cases are characterised by a mild, self-limiting disease course, a considerable subset of patients...

Respiratory sensitization: Advances in assessing the risk of respiratory inflammation and irritation

Respiratory sensitization provides a case study for a new approach to chemical safety evaluation, as the prevalence of respiratory sensitization has increased considerably over the last decades, but animal and/or human experimental/predictive models are not currently available. Therefore, the goal of a working group was to design a road map to...

Skin irritants and contact sensitizers induce Langerhans cell migration and maturation at irritant concentration

Skin irritants and contact allergens reduce the number of Langerhans cells (LCs). It has been assumed that this reduction is due their migration to the draining lymph node (LN) for initiating immune sensitization in a host. Skin irritation, however, as opposed to contact allergy is not considered to be an immunological disease. Nevertheless,...

General aspects of immunotoxicology including validation issues

Histologic examination of lymphoid organs has revealed immunotoxic effects of a broad range of substances. The thymus has proven especially sensitive. The relative lack of sensitivity of mucosa-associated lymphoid cells and tissues may be due to shortcomings in the way they are examined. Validation of ways to examine mucosal lymphoid tissues and...

Non-invasive measurement of brain damage in a primate model of multiple sclerosis

Early recognition of whether a product has potential as a new therapy for treating multiple sclerosis (MS) relies upon the quality of the animal models used in the preclinical trials. The promising effects of new treatments in rodent models of experimental autoimmune encephalomyelitis (EAE) have rarely been reproduced in patients suffering from...

Extended histopathology in immunotoxicity testing: Interlaboratory validation studies

There has been considerable interest in the use of expanded histopathology as a primary screen for immunotoxicity assessment. To determine the utility of a semiquantitative histopathology approach for examining specific structural and architectural changes in lymphoid tissues, a validation effort was initiated. This study addresses the...

Chemically-induced immunopathology and immune functional changes

Toxicological pathology of lymphoid organs plays an important role in the risk assessment process of immunotoxicants. Identification of chemicals that have the potential to cause injury to the immune system is of considerable public health significance because of the role of the immune system in infectious diseases, hypersensitivity reactions...

Health risks associated with inhaled nasal toxicants

Health risks of inhaled nasal toxicants were reviewed with emphasis on chemically induced nasal lesions in humans, sensory irritation, olfactory and trigeminal nerve toxicity, nasal immunopathology and carcinogenesis, nasal responses to chemical mixtures, in vitro models, and nasal dosimetry- and metabolism-based extrapolation of nasal data in...