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Viruses Mar 2023An influenza pandemic happens when a novel influenza A virus is able to infect and transmit efficiently to a new, distinct host species. Although the exact timing of... (Review)
Review
An influenza pandemic happens when a novel influenza A virus is able to infect and transmit efficiently to a new, distinct host species. Although the exact timing of pandemics is uncertain, it is known that both viral and host factors play a role in their emergence. Species-specific interactions between the virus and the host cell determine the virus tropism, including binding and entering cells, replicating the viral RNA genome within the host cell nucleus, assembling, maturing and releasing the virus to neighboring cells, tissues or organs before transmitting it between individuals. The influenza A virus has a vast and antigenically varied reservoir. In wild aquatic birds, the infection is typically asymptomatic. Avian influenza virus (AIV) can cross into new species, and occasionally it can acquire the ability to transmit from human to human. A pandemic might occur if a new influenza virus acquires enough adaptive mutations to maintain transmission between people. This review highlights the key determinants AIV must achieve to initiate a human pandemic and describes how AIV mutates to establish tropism and stable human adaptation. Understanding the tropism of AIV may be crucial in preventing virus transmission in humans and may help the design of vaccines, antivirals and therapeutic agents against the virus.
Topics: Animals; Humans; Influenza in Birds; Influenza A virus; Influenza, Human; Birds; Tropism
PubMed: 37112812
DOI: 10.3390/v15040833 -
Viruses Oct 2022The Epstein-Barr virus (EBV) is associated with a variety of human malignancies, including Burkitt's lymphoma, Hodgkin's disease, nasopharyngeal carcinoma and gastric... (Review)
Review
The Epstein-Barr virus (EBV) is associated with a variety of human malignancies, including Burkitt's lymphoma, Hodgkin's disease, nasopharyngeal carcinoma and gastric cancers. EBV infection is crucial for the oncogenesis of its host cells. The prerequisite for the establishment of infection is the virus entry. Interactions of viral membrane glycoproteins and host membrane receptors play important roles in the process of virus entry into host cells. Current studies have shown that the main tropism for EBV are B cells and epithelial cells and that EBV is also found in the tumor cells derived from NK/T cells and leiomyosarcoma. However, the process of EBV infecting B cells and epithelial cells significantly differs, relying on heterogenous glycoprotein-receptor interactions. This review focuses on the tropism and molecular mechanism of EBV infection. We systematically summarize the key molecular events that mediate EBV cell tropism and its entry into target cells and provide a comprehensive overview.
Topics: Humans; Herpesvirus 4, Human; Epstein-Barr Virus Infections; B-Lymphocytes; Hodgkin Disease; Glycoproteins; Tropism
PubMed: 36366470
DOI: 10.3390/v14112372 -
Cold Spring Harbor Perspectives in... Oct 2020Bone is a frequent site of metastases in many cancers. Both bone properties and the tumor-intrinsic traits are associated with the metastatic propensity to bone (i.e.,... (Review)
Review
Bone is a frequent site of metastases in many cancers. Both bone properties and the tumor-intrinsic traits are associated with the metastatic propensity to bone (i.e., the bone tropism). Whereas an increasing body of mechanistic studies expanded our understanding on bone tropism, they also revealed complexity across the bone lesions originated from different cancer types. In this review, we will discuss the physical, chemical, and biological properties of bone microenvironment, identify potential players in every stage of bone metastases, and introduce some of the known mechanisms regulating the bone colonization. Our objectives are to integrate the knowledge established in different biological contexts and highlight the determinants of bone tropism.
Topics: Animals; Bone Neoplasms; Humans; Osteoclasts; Tropism; Tumor Microenvironment
PubMed: 31615871
DOI: 10.1101/cshperspect.a036848 -
Infection and Immunity May 2023Brucella spp. are facultatively intracellular bacteria that can infect, survive, and multiply in various host cell types and/or . The genus Brucella has markedly... (Review)
Review
Brucella spp. are facultatively intracellular bacteria that can infect, survive, and multiply in various host cell types and/or . The genus Brucella has markedly expanded in recent years with the identification of novel species and hosts, which has revealed additional information about the cell and tissue tropism of these pathogens. Classically, Brucella spp. are considered to have tropism for organs that contain large populations of phagocytes such as lymph nodes, spleen, and liver, as well as for organs of the genital system, including the uterus, epididymis, testis, and placenta. However, experimental infections of several different cultured cell types indicate that Brucella may actually have a broader cell tropism than previously thought. Indeed, recent studies indicate that certain Brucella species in particular hosts may display a pantropic distribution . This review discusses the available knowledge on cell and tissue tropism of Brucella spp. in natural infections of various host species, as well as in experimental animal models and cultured cells.
Topics: Animals; Male; Female; Brucella; Phagocytes; Cell Line; Cells, Cultured; Tropism; Brucellosis
PubMed: 37129522
DOI: 10.1128/iai.00062-23 -
Open Biology May 2019Parasitic diseases, such as sleeping sickness, Chagas disease and malaria, remain a major cause of morbidity and mortality worldwide, but particularly in tropical,... (Review)
Review
Parasitic diseases, such as sleeping sickness, Chagas disease and malaria, remain a major cause of morbidity and mortality worldwide, but particularly in tropical, developing countries. Controlling these diseases requires a better understanding of host-parasite interactions, including a deep appreciation of parasite distribution in the host. The preferred accumulation of parasites in some tissues of the host has been known for many years, but recent technical advances have allowed a more systematic analysis and quantifications of such tissue tropisms. The functional consequences of tissue tropism remain poorly studied, although it has been associated with important aspects of disease, including transmission enhancement, treatment failure, relapse and clinical outcome. Here, we discuss current knowledge of tissue tropism in Trypanosoma infections in mammals, describe potential mechanisms of tissue entry, comparatively discuss relevant findings from other parasitology fields where tissue tropism has been extensively investigated, and reflect on new questions raised by recent discoveries and their potential impact on clinical treatment and disease control strategies.
Topics: Animals; Host-Parasite Interactions; Humans; Organ Specificity; Tissue Distribution; Tropism; Trypanosoma; Trypanosomiasis
PubMed: 31088251
DOI: 10.1098/rsob.190036 -
Viruses May 2022The extrapulmonary manifestation of coronavirus disease-19 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), became apparent early in... (Review)
Review
The extrapulmonary manifestation of coronavirus disease-19 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), became apparent early in the ongoing pandemic. It is now recognized that cells of the cardiovascular system are targets of SARS-CoV-2 infection and associated disease pathogenesis. While some details are emerging, much remains to be understood pertaining to the mechanistic basis by which SARS-CoV-2 contributes to acute and chronic manifestations of COVID-19. This knowledge has the potential to improve clinical management for the growing populations of patients impacted by COVID-19. Here, we review the epidemiology and pathophysiology of cardiovascular sequelae of COVID-19 and outline proposed disease mechanisms, including direct SARS-CoV-2 infection of major cardiovascular cell types and pathogenic effects of non-infectious viral particles and elicited inflammatory mediators. Finally, we identify the major outstanding questions in cardiovascular COVID-19 research.
Topics: COVID-19; Cardiovascular System; Disease Progression; Humans; Pandemics; SARS-CoV-2; Tropism
PubMed: 35746609
DOI: 10.3390/v14061137 -
Viruses Nov 2023Oncolytic viruses (OVs) have emerged as one of the most promising cancer immunotherapy agents that selectively target and kill cancer cells while sparing normal cells.... (Review)
Review
Oncolytic viruses (OVs) have emerged as one of the most promising cancer immunotherapy agents that selectively target and kill cancer cells while sparing normal cells. OVs are from diverse families of viruses and can possess either a DNA or an RNA genome. These viruses also have either a natural or engineered tropism for cancer cells. Oncolytic DNA viruses have the additional advantage of a stable genome and multiple-transgene insertion capability without compromising infection or replication. Herpes simplex virus 1 (HSV-1), a member of the oncolytic DNA viruses, has been approved for the treatment of cancers. This success with HSV-1 was achievable by introducing multiple genetic modifications within the virus to enhance cancer selectivity and reduce the toxicity to healthy cells. Here, we review the natural characteristics of and genetically engineered changes in selected DNA viruses that enhance the tumor tropism of these oncolytic viruses.
Topics: Humans; Oncolytic Virotherapy; Neoplasms; Herpesvirus 1, Human; Oncolytic Viruses; Tropism; DNA Viruses
PubMed: 38005938
DOI: 10.3390/v15112262 -
Cytokine Oct 2023Zika virus (ZIKV) and chikungunya virus (CHIKV) are two medically important vector-borne viruses responsible for causing significant disease burden in humans, including... (Review)
Review
Zika virus (ZIKV) and chikungunya virus (CHIKV) are two medically important vector-borne viruses responsible for causing significant disease burden in humans, including neurological sequelae/complications. Besides sharing some common clinical features, ZIKV has major shares in causing microcephaly and brain malformations in developing foetus, whereas CHIKV causes chronic joint pain/swelling in infected individuals. Both viruses have a common route of entry to the host body. i.e., dermal site of inoculation through the bite of an infected mosquito and later taken up by different immune cells for further dissemination to other areas of the host body that lead to a range of immune responses via different pathways. The immune responses generated by both viruses have similar characteristics with varying degrees of inflammation and activation of immune cells. However, the overall response of immune cells is not fully explored in the context of ZIKV and CHIKV infection. The knowledge of cellular tropism and the immune response is the key to understanding the mechanisms of viral immunity and pathogenesis, which may allow to develop novel therapeutic strategies for these viral infections. This review aims to discuss recent advancements and identify the knowledge gaps in understanding the mechanism of cellular tropism and immune response of CHIKV and ZIKV.
Topics: Animals; Humans; Zika Virus; Chikungunya Fever; Zika Virus Infection; Chikungunya virus; Tropism; Immunity
PubMed: 37579710
DOI: 10.1016/j.cyto.2023.156327 -
Annual Review of Immunology Apr 2022Alphaviruses are emerging and reemerging viruses that cause disease syndromes ranging from incapacitating arthritis to potentially fatal encephalitis. While infection by... (Review)
Review
Alphaviruses are emerging and reemerging viruses that cause disease syndromes ranging from incapacitating arthritis to potentially fatal encephalitis. While infection by arthritogenic and encephalitic alphaviruses results in distinct clinical manifestations, both virus groups induce robust innate and adaptive immune responses. However, differences in cellular tropism, type I interferon induction, immune cell recruitment, and B and T cell responses result in differential disease progression and outcome. In this review, we discuss aspects of immune responses that contribute to protective or pathogenic outcomes after alphavirus infection.
Topics: Alphavirus; Alphavirus Infections; Animals; Humans; Immunity; Interferon Type I; Tropism
PubMed: 35134315
DOI: 10.1146/annurev-immunol-101220-014952 -
Frontiers in Cellular and Infection... 2020Orthohantaviruses are zoonotic viruses that are naturally maintained by persistent infection in specific reservoir species. Although these viruses mainly circulate among... (Review)
Review
Orthohantaviruses are zoonotic viruses that are naturally maintained by persistent infection in specific reservoir species. Although these viruses mainly circulate among rodents worldwide, spill-over infection to humans occurs. Orthohantavirus infection in humans can result in two distinct clinical outcomes: hemorrhagic fever with renal syndrome (HFRS) and hantavirus cardiopulmonary syndrome (HCPS). While both syndromes develop following respiratory transmission and are associated with multi-organ failure and high mortality rates, little is known about the mechanisms that result in these distinct clinical outcomes. Therefore, it is important to identify which cell types and tissues play a role in the differential development of pathogenesis in humans. Here, we review current knowledge on cell tropism and its role in pathogenesis during orthohantavirus infection in humans and reservoir rodents. Orthohantaviruses predominantly infect microvascular endothelial cells (ECs) of a variety of organs (lungs, heart, kidney, liver, and spleen) in humans. However, in this review we demonstrate that other cell types (e.g., macrophages, dendritic cells, and tubular epithelium) are infected as well and may play a role in the early steps in pathogenesis. A key driver for pathogenesis is increased vascular permeability, which can be direct effect of viral infection in ECs or result of an imbalanced immune response in an attempt to clear the virus. Future studies should focus on the role of identifying how infection of organ-specific endothelial cells as well as other cell types contribute to pathogenesis.
Topics: Endothelial Cells; Orthohantavirus; Hantavirus Infections; Hemorrhagic Fever with Renal Syndrome; Humans; Tropism
PubMed: 32903721
DOI: 10.3389/fcimb.2020.00399