Search results for "immune responses"
showing 9 items of 9 documents
Primary in vivo T cell reactivity of NZB grafts in H-2 identical allogenic hosts.
1983
By means of the Simonson GVH-assay and the popliteal lymph node (PLN) assay, the T-cell reactivity of NZB mice against H-2 identical allogenic cells was investigated in vivo and compared to that of normal mice. None of the normal mice did react, but a highly significant NZB response could be demonstrated, which did not depend on differences in Mls antigens. These in vivo results extend previous findings of a T-cell hyperreactivity of NZB mice in primary in vitro reactions. They favour the possibility that the T-cell hyperreactivity might be relevant in vivo in facilitating autoimmune responses.
Prophenoloxidase activating system in tunicate hemolymph
1996
The activation sequence and related factors of the prophenoloxidase activating system in crustaceans was compared with the equivalent system in tunicates. Both solitary and colonial ascidians present in their hemolymph a copper-dependent phenoloxidase activity that may be inhibited by tropolone and phenylthiourea. Carbohydrates are able, to various extents, to trigger proPO system which requires serine protease cleavage for activation to phenoloxidase (PO). In some ascidians, hemocytes called ≪morula cells≫ show PO activity, while in Ciona intestinalis the ≪univacuolar refractile granulocytes≫ are positive after cytochemical staining with L-dopa. The relationships between proPO system and d…
Role of PRRs (TLR2 and Dectin-1) in hematopoietic stem and progenitor cell differentiation: implications in protection against Candida albicans infec…
2020
Detection of infection by hematopoietic stem and progenitor cells (HSPCs) is essential to replace myeloid cells consumed during the immune response. HSPCs express some functional pattern recognition receptors involved in the recognition of Candida albicans. In this context, our group has previously demonstrated that C. albicans yeasts induce proliferation and differentiation of HSPCs via TLR2 and Dectin-1. In the present PhD thesis, we used in vitro and ex vivo models of HSPC differentiation to investigate the functional consequences for mature myeloid cells of exposure of HSPCs to PAMPs or C. albicans yeasts. In vitro experiments show that murine HSPCs continuously exposed to TLR2 or TLR4 …
Biomaterial Surface Hydrophobicity-Mediated Serum Protein Adsorption and Immune Responses.
2019
The nature of the protein corona forming on biomaterial surfaces can affect the performance of implanted devices. This study investigated the role of surface chemistry and wettability on human serum-derived protein corona formation on biomaterial surfaces and the subsequent effects on the cellular innate immune response. Plasma polymerization, a substrate-independent technique, was employed to create nanothin coatings with four specific chemical functionalities and a spectrum of surface charges and wettability. The amount and type of protein adsorbed was strongly influenced by surface chemistry and wettability but did not show any dependence on surface charge. An enhanced adsorption of the …
Invasive candida infections in neonates after major surgery: Current evidence and new directions
2021
Infections represent a serious health problem in neonates. Invasive Candida infections (ICIs) are still a leading cause of mortality and morbidity in neonatal intensive care units (NICUs). Infants hospitalized in NICUs are at high risk of ICIs, because of several risk factors: broad spectrum antibiotic treatments, central catheters and other invasive devices, fungal colonization, and impaired immune responses. In this review we summarize 19 published studies which provide the prevalence of previous surgery in neonates with invasive Candida infections. We also provide an overview of risk factors for ICIs after major surgery, fungal colonization, and innate defense mechanisms against fungi, a…
Centenarians born before 1919 are resistant to COVID-19.
2022
Although mortality from COVID-19 progressively increases with age, there are controversial data in the literature on the probability of centenarians dying from COVID-19. Moreover, it has been claimed that men in their 90s and 100s are more resilient than women. To gain insight into this matter, we analysed, according to gender, mortality data during the first year of pandemic of Sicilian nonagenarians and centenarians. We used mortality data from the 2019 as a control. The crude excess mortality between the two years was calculated. Data on deaths of Sicilian 90 + years show that, in line with what is known about the different response to infections between the two genders, oldest females a…
Role of sex and age in fatal outcomes of COVID-19: women and older centenarians are more resilient.
2023
In the present paper, we have analysed the role of age and sex in the fatal outcome of COVID-19, as there are conflicting results in the literature. As such, we have answered three controversial questions regarding this aspect of the COVID-19 pandemic: (1) Have women been more resilient than men? (2) Did centenarians die less than the remaining older people? (3) Were older centenarians more resistant to SARS-CoV-2 than younger centenarians? The literature review demonstrated that: (1) it is women who are more resilient, in agreement with data showing that women live longer than men even during severe famines and epidemics; however, there are conflicting data regarding centenarian men; (2) c…
Correction to: Echinodermata: The complex immune system in echinoderms (Advances in Comparative Immunology, 10.1007/978-3-319-76768-0_13)
2018
This chapter was inadvertently published with an incorrect spelling of the author's name as V. Arriza whereas it should be V. Arizza. In addition to this the affiliation of one of the chapter authors Elisse Sutton was published incorrectly and it has now been corrected to read as Department of Biological Sciences, Macquarie University, Sydney, NSW, Australia.
Echinodermata: The complex immune system in echinoderms
2018
View references (418) The Echinodermata are an ancient phylum of benthic marine invertebrates with a dispersal-stage planktonic larva. These animals have innate immune systems characterized initially by clearance of foreign particles, including microbes, from the body cavity of both larvae and adults, and allograft tissue rejection in adults. Immune responsiveness is mediated by a variety of adult coelomocytes and larval mesenchyme cells. Echinoderm diseases from a range of pathogens can lead to mass die-offs and impact aquaculture, but some individuals can recover. Genome sequences of several echinoderms have identified genes with immune function, including expanded families of Toll-like r…