scholarly journals Pegivirus avoids immune recognition but does not attenuate acute-phase disease in a macaque model of HIV infection

2017 ◽  
Author(s):  
Adam L. Bailey ◽  
Connor R. Buechler ◽  
Daniel R. Matson ◽  
Eric J. Peterson ◽  
Kevin G. Brunner ◽  
...  
Keyword(s):  
Immune System ◽  
Hiv Infection ◽  
Protective Effect ◽  
Acute Phase ◽  
Human Population ◽  
Chronic Phase ◽  
Immune Recognition ◽  
Irreversible Damage ◽  
Macaque Model ◽  
High Prevalence

AbstractHuman pegivirus (HPgV) protects HIV+ people from HIV-associated disease, but the mechanism of this protective effect remains poorly understood. We sequentially infected cynomolgus macaques with simian pegivirus (SPgV) and simian immunodeficiency virus (SIV) to model HIV+HPgV co-infection. SPgV had no effect on acute-phase SIV pathogenesis – as measured by SIV viral load, CD4+ T cell destruction, and immune activation – suggesting that HPgV’s protective effect is exerted primarily during the chronic phase of HIV infection. We also examined the immune response to SPgV in unprecedented detail, and found that this virus elicits virtually no activation of the immune system despite persistently high titers in the blood over long periods of time. Overall, this study expands our understanding of the pegiviruses – an understudied group of viruses with a high prevalence in the global human population – and suggests that the protective effect observed in HIV+HPgV co-infected people occurs primarily during the chronic phase of HIV infection.One Sentence SummaryPegivirus avoids immune recognition but does not attenuate acute-phase disease in a macaque model of HIV infection.Short TitlePegivirus and AIDS-virus co-infectionAccessible SummaryPeople infected with HIV live longer, healthier lives when they are co-infected with the human pegivirus (HPgV) – an understudied virus with a high prevalence in the global human population. To better understand how HPgV protects people with HIV from HIV-associated disease, we infected macaques with simian versions of these two viruses (SPgV and SIV). We found that SPgV had no impact on the incidence of SIV-associated disease early during the course of SIV infection – a time when SIV and HIV are known to cause irreversible damage to the immune system. Oddly, we found that the immune system did not recognize SPgV; a finding that warrants further investigation. Overall, this study greatly expands on our understanding of the pegiviruses and their interaction with the immune system.

scholarly journals Pegivirus avoids immune recognition but does not attenuate acute-phase disease in a macaque model of HIV infection

2017 ◽  
Vol 13 (10) ◽  
pp. e1006692 ◽  
Author(s):  
Adam L. Bailey ◽  
Connor R. Buechler ◽  
Daniel R. Matson ◽  
Eric J. Peterson ◽  
Kevin G. Brunner ◽  
...  
Keyword(s):  
Hiv Infection ◽  
Acute Phase ◽  
Immune Recognition ◽  
Macaque Model

scholarly journals Influence of Acute-Phase Parasite Load on Pathology, Parasitism, and Activation of the Immune System at the Late Chronic Phase of Chagas’ Disease

1999 ◽  
Vol 67 (1) ◽  
pp. 308-318 ◽  
Author(s):  
Claudio R. F. Marinho ◽  
Maria Regina D’Império Lima ◽  
Marcos G. Grisotto ◽  
José M. Alvarez
Keyword(s):  
Immune System ◽  
Chagas Disease ◽  
Acute Phase ◽  
Serum Antibody ◽  
Chronic Phase ◽  
Parasite Load ◽  
Interleukin 4 ◽  
High Dose ◽  
Macrophage Phenotype ◽  
High Parasite

ABSTRACT To obtain low and high parasite loads in the acute phase of Chagas’ disease, A/J mice were infected with 103 or 105 Trypanosoma cruzi trypomastigotes of the Y strain and treated on day 6 with benznidazol. One year later, chronically infected mice were screened for subpatent parasitemias, tissue pathology, and immune response. Mice infected with the high parasite inoculum showed higher levels of chronic parasitemias, heart and striated muscle inflammation, and activation of the immune system than did mice infected with the low inoculum. Concerning the activation of the immune system, the main findings for high-dose-infected mice were (i) increased numbers of splenocytes, with preferential expansion of CD8+ and B220− CD5− cells, many of them bearing a macrophage phenotype; (ii) higher frequencies of B (B220+), CD4+, and CD8+ large lymphocytes; (iii) a shift of CD4+ cells towards a CD45RBLow phenotype; (iv) increased frequencies of both CD45RBLow and CD45RBHigh large CD4+cells; (v) augmented numbers of total immunoglobulin (Ig)-secreting cells, with predominance of IgG2a-producing cells; and (vi) increased production of gamma interferon and interleukin 4. In addition, these mice presented lower IgM and higher IgG2a and IgG1 parasite-specific serum antibody levels. Our results indicate that the parasite load at the acute phase of T. cruzi infection influences the activation of the immune system and development of Chagas’ disease pathology at the late chronic phase of the disease.

scholarly journals Frequencies of Blood Group Systems MNS, Diego, and Duffy and Clinical Phases of Carrion’s Disease in Amazonas, Peru

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Oscar Acosta ◽  
Luis Solano ◽  
Jorge Escobar ◽  
Miguel Fernandez ◽  
Carlos Solano ◽  
...  
Keyword(s):  
Blood Group ◽  
Acute Phase ◽  
Chronic Phase ◽  
Allele Frequencies ◽  
Gene Frequencies ◽  
Bartonella Bacilliformis ◽  
The Andes ◽  
High Prevalence ◽  
The Relationship ◽  
Genetic Context

Carrion’s disease (CD), is a human bartonellosis, that is, endemic in the Andes of Peru, Ecuador, and Colombia.Bartonella bacilliformis, a native hemotrophic bacteria, is the causative agent of CD, and the interaction with the host could have produced changes in the gene frequencies of erythrocyte antigens. The goal here is to investigate the relationship between allele frequencies of blood group systems MNS, Diego, and Duffy and the clinical phases of CD, within a genetic context. In this associative and analytical study, 76 individuals from Bagua Grande, the province of Utcubamba, and the department of Amazonas in Peru, were enrolled. Forty of them resided in Tomocho-Collicate-Vista Hermosa area (high prevalence of cases in chronic phase, verrucous, or eruptive phase, without previous acute phase). Thirty-six individuals were from the area of Miraflores (high prevalence of cases in acute phase only) and were evaluated for blood group systems MNS, Diego, and Duffy. This study constitutes one of the first attempts at evaluating the genetic factors and clinical phases of CD. No significant statistical differences(P>0.05)between allele frequencies of blood groups MNS, Diego, and Duffy and the prevalence of chronic and acute phases were detected in the two areas of Amazonas, Peru.

scholarly journals Prevalence of Hiv Infection Among Pregnant Women Attending Ajiko Medical Clinic, Damaturu, Nigeria

2019 ◽  
Vol 3 (4) ◽  
pp. 7-9
Author(s):  
Sabina Khanam
Keyword(s):  
Immune System ◽  
Hiv Infection ◽  
Pregnant Women ◽  
Older Women ◽  
Prevalence Rate ◽  
Age Groups ◽  
Medical Clinic ◽  
Age Group ◽  
High Prevalence ◽  
Human Immunodeficiency Viruses

Human immunodeficiency viruses causes HIV infection in humans belongs to two species of Lentivirus. It damages the cells of immune system which leads to weak immune system and the ability to fight from infections and diseases. This study was conducted to investigate the prevalence rate of HIV infection among pregnant women of different age groups attending Ajiko medical clinic, Damaturu, Nigeria. The prevalence rate was maximum (12.5%) in 36-45 age group and minimum (5%) in 26-35 age group but their was no HIV infection in 15-25 age group. The overall prevalence rate among pregnant women was 4%. General knowledge , training and campaigns of HIV prevention need to be tailored towards older women of age group 36-45 because of high prevalence rate.

Redox-Active Selenium in Health and Disease: A Conceptual Review

2019 ◽  
Vol 19 (9) ◽  
pp. 720-726 ◽  
Author(s):  
Boguslaw Lipinski
Keyword(s):  
Food Supplement ◽  
Biologically Active ◽  
Immune Recognition ◽  
Potential Candidate ◽  
Irreversible Damage ◽  
Human Fibrinogen ◽  
Virus Attachment ◽  
Redox Active ◽  
Health And Disease ◽  
Highly Hydrophobic

Although it is generally accepted that selenium (Se) is important for life, it is not well known which forms of organic and/or inorganic Se compound are the most biologically active. In nature Se exists mostly in two forms, namely as selenite with fourvalent and selenate with sixvalent cations, from which all other inorganic and organic species are derived. Despite a small difference in their electronic structure, these two inorganic parent compounds differ significantly in their redox properties. Hence, only selenite can act as an oxidant, particularly in the reaction with free and/or protein- bound sulhydryl (SH) groups. For example, selenite was shown to inhibit the hydroxyl radicalinduced reduction and scrambled reoxidation of disulfides in human fibrinogen thus preventing the formation of highly hydrophobic polymer, termed parafibrin. Such a polymer, when deposited within peripheral and/or cerebral circulation, may cause irreversible damage resulting in the development of cardiovascular, neurological and other degenerative diseases. In addition, parafibrin deposited around tumor cells produces a protease-resistant coat protecting them against immune recognition and elimination. On the other hand, parafibrin generated by Ebola’s protein disulfide isomerase can form a hydrophobic ‘spike’ that facilitates virus attachment and entry to the host cell. In view of these specific properties of selenite this compound is a potential candidate as an inexpensive and readily available food supplement in the prevention and/or treatment of cardiovascular, neoplastic, neurological and infectious diseases.

Kinetic Aspects of the Interplay of Cancer and the Immune System

2019 ◽  
Vol 14 (02) ◽  
pp. 101-114 ◽  
Author(s):  
Vladimir P. Zhdanov
Keyword(s):  
Stem Cells ◽  
Immune System ◽  
Kinetic Model ◽  
Human Population ◽  
Lifetime Risk ◽  
Risk Of Cancer

The understanding of the interplay between cancer and the immune system is still limited. Herein, I focus on two aspects of this interplay. First, I propose a kinetic model describing the likely role of the immune system in the lifetime risk of cancer at the level of the whole human population. For each tissue, the risk is predicted to be influenced by the heterogeneity of the population and to depend exponentially on time. The expression for the risk does not, however, depend explicitly on the total number of divisions of the corresponding stem cells. For this reason, the correlation with the latter number can only be indirect. Second, using another kinetic framework, I describe how the growth of a few tumors can depend on their interaction via the immune system. The analysis shows that depending on specific details, the tumors of different sizes tend either to reach the same size or remain to be of different sizes.

scholarly journals Why Does SARS-CoV-2 Infection Induce Autoantibody Production?

Pathogens ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 380
Author(s):  
Ales Macela ◽  
Klara Kubelkova
Keyword(s):  
Immune Response ◽  
Immune System ◽  
Host Cell ◽  
Critical Role ◽  
Cell Interaction ◽  
Immune Recognition ◽  
Autoantibody Production ◽  
Host Cell Interaction ◽  
Primary Virus

SARS-CoV-2 infection induces the production of autoantibodies, which is significantly associated with complications during hospitalization and a more severe prognosis in COVID-19 patients. Such a response of the patient’s immune system may reflect (1) the dysregulation of the immune response or (2) it may be an attempt to regulate itself in situations where the non-infectious self poses a greater threat than the infectious non-self. Of significance may be the primary virus-host cell interaction where the surface-bound ACE2 ectoenzyme plays a critical role. Here, we present a brief analysis of recent findings concerning the immune recognition of SARS-CoV-2, which, we believe, favors the second possibility as the underlying reason for the production of autoantibodies during COVID-19.

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