Trends in Biomathematics: Stability and Oscillations in Environmental, Social, and Biological Models: Selected Works from the BIOMAT Consortium Lectures, Rio de Janeiro, Brazil, 2021

This contributed volume convenes selected, peer-reviewed works presented at the BIOMAT 2021 International Symposium, which was virtually held on November 1-5, 2021, with its organization staff based in Rio de Janeiro, Brazil. In this volume the reader will find applications of mathematical modeling on health, ecology, and social interactions, addressing topics like probability distributions of mutations in different cancer cell types;oscillations in biological systems;modeling of marine ecosystems;mathematical modeling of organs and tissues at the cellular level;as well as studies on novel challenges related to COVID-19, including the mathematical analysis of a pandemic model targeting effective vaccination strategy and the modeling of the role of media coverage on mitigating the spread of infectious diseases. Held every year since 2001, the BIOMAT International Symposium gathers together, in a single conference, researchers from Mathematics, Physics, Biology, and affine fields to promote the interdisciplinary exchange of results, ideas and techniques, promoting truly international cooperation for problem discussion. BIOMAT volumes published from 2017 to 2020 are also available by Springer. © The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Switzerland AG 2022.

Airway and Alveoli Organoids as Valuable Research Tools in COVID-19.

The coronavirus disease 2019 (COVID-19), caused by the novel coronavirus, SARS-CoV-2, affects tissues from different body systems but mostly the respiratory system, and the damage evoked in the lungs may occasionally result in severe respiratory complications and eventually lead to death. Studies of human respiratory infections have been limited by the scarcity of functional models that mimic in vivo physiology and pathophysiology. In the last decades, organoid models have emerged as potential research tools due to the possibility of reproducing in vivo tissue in culture. Despite being studied for over one year, there is still no effective treatment against COVID-19, and investigations using pulmonary tissue and possible therapeutics are still very limited. Thus, human lung organoids can provide robust support to simulate SARS-CoV-2 infection and replication and aid in a better understanding of their effects in human tissue. The present review describes methodological aspects of different protocols to develop airway and alveoli organoids, which have a promising perspective to further investigate COVID-19.

Animal Hosts and Experimental Models of SARS-CoV-2 Infection.

Viruses arise through cross-species transmission and can cause potentially fatal diseases in humans. This is the case of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) which recently appeared in Wuhan, China, and rapidly spread worldwide, causing the outbreak of coronavirus disease 2019 (COVID-19) and posing a global health emergency. Sequence analysis and epidemiological investigations suggest that the most likely original source of SARS-CoV-2 is a spillover from an animal reservoir, probably bats, that infected humans either directly or through intermediate animal hosts. The role of animals as reservoirs and natural hosts in SARS-CoV-2 has to be explored, and animal models for COVID-19 are needed as well to be evaluated for countermeasures against SARS-CoV-2 infection. Experimental cells, tissues, and animal models that are currently being used and developed in COVID-19 research will be presented.

Cell and animal models of SARS-CoV-2 pathogenesis and immunity.

The spread of the novel virus SARS coronavirus 2 (SARS-CoV-2) was explosive, with cases first identified in December 2019, and >22 million people infected and >775,000 deaths as of August 2020. SARS-CoV-2 can cause severe respiratory disease in humans leading to coronavirus disease 2019 (COVID-19). The development of effective clinical interventions, such as antivirals and vaccines that can limit or even prevent the burden and spread of SARS-CoV-2, is a global health priority. Testing of leading antivirals, monoclonal antibody therapies and vaccines against SARS-CoV-2 will require robust animal and cell models of viral pathogenesis. In this Special Article, we discuss the cell-based and animal models of SARS-CoV-2 infection and pathogenesis that have been described as of August 2020. We also outline the outstanding questions for which researchers can leverage animal and cell-based models to improve our understanding of SARS-CoV-2 pathogenesis and protective immunity. Taken together, the refinement of models of SARS-CoV-2 infection will be critical to guide the development of therapeutics and vaccines against SARS-CoV-2 to end the COVID-19 pandemic.

In Vitro and Animal Models for SARS-CoV-2 research.

Basic research on SARS-CoV-2 is essential to understand its detailed pathophysiology and identify best drug targets. Models that can faithfully reproduce the viral life cycle and reproduce the pathology of COVID-19 are required. Here, we briefly review the cell lines, organoids, and animal models that are currently being used in COVID-19 research.