scholarly journals Is it of any positive being COVID-19 positive?: cross-protection hypothesis

2021 ◽  
Author(s):  
Muath Alser
Keyword(s):  
Immune Responses ◽  
Cross Protection ◽  
Cross Reactions ◽  
Beneficial Effects ◽  
Shared Epitopes

Many pathogens have been reported to induce cross-protective immune responses against other related and unrelated pathogens due to shared epitopes or induction of trained immunity.Herein, I review the evidence we have so far on the possible SARS-CoV-2 cross-reactions with other pathogens, and the immune modulatory effects it could induce, which could lead to beneficial effects against other diseases among COVID-19-recovered immunocompetent individuals.

Characterization ofTrypanosoma congolenseserodemes in stocks isolated from Chipata District, Zambia

Parasitology ◽  
1990 ◽  
Vol 101 (2) ◽  
pp. 235-241 ◽  
Author(s):  
I. A. Frame ◽  
C. A. Ross ◽  
A. G. Luckins
Keyword(s):  
Immune Responses ◽  
Fluorescent Antibody ◽  
Antibody Test ◽  
Cross Protection ◽  
Cross Reactions ◽  
Serological Typing ◽  
Reference Collection ◽  
Variable Antigen ◽  
Formalin Fixed

Six stocks ofTrypanosoma congolensewere cloned from 17 stocks isolated from Eastern Zambia and used to initiate insect-formin vitrocultures producing metacyclic trypanosomes. Serological assays were then developed using thesein vitro-derived metacyclics as a reference collection of antigens. Monoclonal antibodies recognized 8 metacyclic variable antigen types (M-VATs) of one stock,T. congolenseTREU 1885, representing 70–80% of that stock's M-VAT repertoire, and in an indirect fluorescent antibody test (IFAT) there were no cross-reactions between them and the metacyclic trypanosomes of the other 5 stocks. Cross-protection assays between the 6 stocks in mice showed that the stocks culturedin vitrowere serologically distinct. In order to facilitate serological typing for serodeme characterization, an IFAT was developed using formalin-fixed metacyclic trypanosomes to identify VAT specific immune responses using 21 day post-infection antisera. The cultured stocks reacted only with their homologous antisera thus confirming the results obtained in the cross-protection assays. No cross-reactions were observed with the 6 cloned stocks and antisera against the 11 stocks ofT. congolenseisolated in the same area at the same time suggesting that these stocks were different from the reference collection of cultured metacyclics. Hence, at least 7 serodemes ofT. congolensehave been identified from the 17 stocks isolated.

Healthy Effects Exerted by Prebiotics, Probiotics, and Symbiotics with Special Reference to their Impact on the Immune System

2012 ◽  
Vol 82 (3) ◽  
pp. 200-208 ◽  
Author(s):  
Emilio Jirillo ◽  
Felicita Jirillo ◽  
Thea Magrone
Keyword(s):  
Immune Responses ◽  
Tumor Development ◽  
The Elderly ◽  
Adaptive Immune Responses ◽  
Free Living ◽  
Beneficial Effects ◽  
Adaptive Immune ◽  
Inflammatory Conditions ◽  
Reduced Frequency ◽  
Inflammatory Bowel

Pre-, pro-, and symbiotics are endowed with a broad spectrum of beneficial effects when administered to animals and humans. A series of experimental and clinical studies have clearly demonstrated that prebiotics, probiotics, or their combination are very effective in attenuating chronic inflammatory conditions such as inflammatory bowel disease or obesity. In addition, these natural products are able to prevent or arrest tumor development, acting on the intestinal microbiota as well as potentiating the immune response.Aging is characterized by a dramatic reduction of both innate and adaptive immune responses, the so-called immunosenescence. This leads to an increased incidence of infections, autoimmune diseases, and cancer in the elderly. Pre-, pro-, and symbiotic administration has been shown to ameliorate the immune response in aging. In particular, administration of a symbiotic to free-living elderly was able to potentiate the release of interleukin-8, thus increasing neutrophils in the host, perhaps explaining the reduced frequency of winter infections in the elderly.

Aspirin and P2Y12 Inhibitors in platelet-mediated activation of neutrophils and monocytes

2015 ◽  
Vol 114 (09) ◽  
pp. 478-789 ◽  
Author(s):  
Waltraud Schrottmaier ◽  
Julia Kral ◽  
Sigrun Badrnya ◽  
Alice Assinger
Keyword(s):  
Immune Responses ◽  
Antiplatelet Therapy ◽  
Inflammatory Responses ◽  
Current Knowledge ◽  
Inflammatory Diseases ◽  
Cardiovascular Complications ◽  
P2y12 Inhibitors ◽  
Beneficial Effects ◽  
Cox Inhibitor ◽  
The Impact

SummaryPlatelets are key players in haemostasis and represent a pivotal link between inflammation, immunity and atherogenesis. Depending on the (patho)physiological environment platelets modulate various leukocyte functions via release of inflammatory mediators and direct cell-cell interactions. Elevated levels of circulating platelet-leukocyte aggregates are found in patients suffering from several thrombotic or inflammatory conditions. Platelet-monocyte and platelet-neutrophil interaction can trigger pro- and anti-inflammatory responses and modulate effector functions of all leukocyte subpopulations. These platelet-mediated immune responses have implications for the progression of cardiovascular diseases and also play a crucial role during infections, cancer, transplantations and other inflammatory diseases of several organs. Antiplatelet therapy including the COX inhibitor aspirin and/or ADP receptor P2Y12 inhibitors such as clopidogrel, prasugrel and ticagrelor are the therapy of choice for various cardiovascular complications. Both aspirin and P2Y12 inhibitors attenuate platelet-leukocyte interactions, thereby also modulating immune responses. This may have beneficial effects in some pathological conditions, while it might be detrimental in others. This review aims to summarise the current knowledge on platelet-leukocyte interactions and the impact of aspirin and P2Y12 inhibition on platelet-mediated immune responses and to give an overview on the effects of antiplatelet therapy on platelet-leukocyte interplay in various diseases.

scholarly journals CROSS-REACTIONS AMONG GROUP A STREPTOCOCCI

1968 ◽  
Vol 128 (5) ◽  
pp. 959-968 ◽  
Author(s):  
Grove G. Wiley ◽  
Pauline N. Bruno
Keyword(s):  
Streptococcal Infection ◽  
Cross Protection ◽  
The Other ◽  
Group A Streptococci ◽  
Agar Gel ◽  
Cross Reactions ◽  
Group A ◽  
Spur Formation ◽  
Homologous Reaction

Strains of four streptococcal types, 33, 41, 43, 52, and a nontypable strain, Ross, cross-reacted in precipitin and bactericidal tests. The homologous reactions, which determined the type, afforded the major protection and developed promptly and regularly in the serum of rabbits during immunization. The associated cross-reactions, on the other hand, appeared in the serum of certain rabbits only, were often not as strong as the associated homologous reactions, and required for their presence a longer period of immunization than the homologous reactions. Agar gel analysis of the homologous precipitin reactions revealed, as would be expected, reactions of serological identity, while those cross-reactions which were strong enough to test in this way formed bands of precipitate which joined with spur formation on the side of the homologous reaction. These experiments and others referred to in the text suggest that cross-protection, as demonstrated in bactericidal tests, is sufficiently widespread to be a factor in streptococcal immunity, if a corresponding protection occurs in vivo. Thus, streptococcal infection with one of the cross-reacting strains might confer, in addition to strong homologous protection, a certain amount of cross-protection.

scholarly journals Impact of the Conjugation Method on the Immunogenicity ofStreptococcus pneumoniaeSerotype 19F Polysaccharide in Conjugate Vaccines

2010 ◽  
Vol 18 (2) ◽  
pp. 327-336 ◽  
Author(s):  
Jan Poolman ◽  
Carl Frasch ◽  
Anu Nurkka ◽  
Helena Käyhty ◽  
Ralph Biemans ◽  
...  
Keyword(s):  
Immune Responses ◽  
Pneumococcal Disease ◽  
Reductive Amination ◽  
Acute Otitis Media ◽  
Cross Protection ◽  
Native Form ◽  
Conjugate Vaccines ◽  
Pneumococcal Conjugate Vaccines ◽  
The Impact ◽  
Conjugation Method

ABSTRACT7vCRM (Pfizer, Inc.) and PHiD-CV (GlaxoSmithKline Biologicals) are two pneumococcal conjugate vaccines licensed for the prevention of invasive pneumococcal disease and acute otitis media caused by the vaccine serotypes ofStreptococcus pneumoniae. Neither vaccine contains serotype 19A, but both contain the closely related serotype 19F. No decrease in the incidence of serotype 19A disease has been observed following the introduction of 7vCRM, suggesting that this serotype 19F-containing vaccine provides limited cross-protection against serotype 19A. To investigate the impact that conjugation methods may have on antipolysaccharide immune responses and to determine whether this limited cross-protection is characteristic of the serotype 19F polysaccharide or rather of the 19F-CRM (cross-reacting material) conjugate, we compared naturally induced antibodies against serotypes 19F and 19A with antibodies induced after vaccination with different pneumococcal conjugate vaccines. We found that conjugation of the serotype 19F polysaccharide using reductive amination (as in 7vCRM) resulted in the formation of at least one additional epitope that is not present in the native form of the 19F polysaccharide or following 19F conjugation using a bifunctional spacer (as in the prototype vaccine 7vOMPC) or cyanylation (as in PHiD-CV). We also found that pneumococcal vaccines conjugated using cyanylation induce more opsonophagocytic antibodies against serotype 19F and a considerably higher level of cross-opsonophagocytic antibodies against serotype 19A than vaccines conjugated using reductive amination. In conclusion, these results suggest that the conjugation method can influence the functionality of the antibodies induced against the homologous serotype 19F and the cross-reactive serotype 19A ofS. pneumoniae.

scholarly journals Mechanisms of Action of Probiotics in Intestinal Diseases

2007 ◽  
Vol 7 ◽  
pp. 31-46 ◽  
Author(s):  
Ann M. O'Hara ◽  
Fergus Shanahan
Keyword(s):  
Immune Responses ◽  
Molecular Mechanisms ◽  
Clinical Medicine ◽  
Mechanisms Of Action ◽  
Host Cells ◽  
Positive Health ◽  
Beneficial Effects ◽  
Potential Therapeutic Role ◽  
Conditioning Effect ◽  
Clinical Conditions

Intestinal microbiota is a positive health asset that exerts a conditioning effect on intestinal homeostasis. Resident bacteria deliver regulatory signals to the epithelium and instruct mucosal immune responses. Recent research has revealed a potential therapeutic role for the manipulation of the microbiota and exploitation of host-microbial signalling pathways in the maintenance of human health and treatment of various mucosal disorders. A variety of pharmabiotic strategies, such as the use of specific members of the microbiota, their surface components, or metabolites, as well as genetically modified commensal bacteria, are being investigated for their ability to enhance the beneficial components of the microbiota. It is clear that engagement with host cells is central to pharmabiotic action, and several strain-specific mechanisms of action have been elucidated. However, the molecular details underpinning these mechanisms remain almost entirely unknown. Understanding how pharmabiotics exert their beneficial effects is critical for the establishment of definitive selection criteria for certain pharmabiotic strategies for specific clinical conditions. Scientifically accredited evidence of efficacy and studies to elucidate the molecular mechanisms of host-microbiota interactions are needed to lend credence to the use of pharmabiotic strategies in clinical medicine.

scholarly journals A Combination Adjuvant for the Induction of Potent Antiviral Immune Responses for a Recombinant SARS-CoV-2 Protein Vaccine

2021 ◽  
Vol 12 ◽  
Author(s):  
Sonia Jangra ◽  
Jeffrey J. Landers ◽  
Raveen Rathnasinghe ◽  
Jessica J. O’Konek ◽  
Katarzyna W. Janczak ◽  
...  
Keyword(s):  
Immune Responses ◽  
Neutralizing Antibody ◽  
Cellular Responses ◽  
Cross Protection ◽  
Protein Vaccine ◽  
Mucosal Vaccination ◽  
Adaptive Immune ◽  
Antibody Titers ◽  
High Virus

Several SARS-CoV-2 vaccines have received EUAs, but many issues remain unresolved, including duration of conferred immunity and breadth of cross-protection. Adjuvants that enhance and shape adaptive immune responses that confer broad protection against SARS-CoV-2 variants will be pivotal for long-term protection as drift variants continue to emerge. We developed an intranasal, rationally designed adjuvant integrating a nanoemulsion (NE) that activates TLRs and NLRP3 with an RNA agonist of RIG-I (IVT DI). The combination adjuvant with spike protein antigen elicited robust responses to SARS-CoV-2 in mice, with markedly enhanced TH1-biased cellular responses and high virus-neutralizing antibody titers towards both homologous SARS-CoV-2 and a variant harboring the N501Y mutation shared by B1.1.7, B.1.351 and P.1 variants. Furthermore, passive transfer of vaccination-induced antibodies protected naive mice against heterologous viral challenge. NE/IVT DI enables mucosal vaccination, and has the potential to improve the immune profile of a variety of SARS-CoV-2 vaccine candidates to provide effective cross-protection against future drift variants.

scholarly journals Molecular Repolarisation of Tumour-Associated Macrophages

Molecules ◽  
2018 ◽  
Vol 24 (1) ◽  
pp. 9 ◽  
Author(s):  
Floris van Dalen ◽  
Marleen van Stevendaal ◽  
Felix Fennemann ◽  
Martijn Verdoes ◽  
Olga Ilina
Keyword(s):  
Immune Responses ◽  
Immune Cells ◽  
Growth And Development ◽  
Tumour Microenvironment ◽  
Environmental Cues ◽  
Preclinical Models ◽  
Beneficial Effects ◽  
Macrophage Depletion ◽  
Cytotoxic Effector ◽  
Tumour Proliferation

The tumour microenvironment (TME) is composed of extracellular matrix and non-mutated cells supporting tumour growth and development. Tumour-associated macrophages (TAMs) are among the most abundant immune cells in the TME and are responsible for the onset of a smouldering inflammation. TAMs play a pivotal role in oncogenic processes as tumour proliferation, angiogenesis and metastasis, and they provide a barrier against the cytotoxic effector function of T lymphocytes and natural killer (NK) cells. However, TAMs are highly plastic cells that can adopt either pro- or anti-inflammatory roles in response to environmental cues. Consequently, TAMs represent an attractive target to recalibrate immune responses in the TME. Initial TAM-targeted strategies, such as macrophage depletion or disruption of TAM recruitment, have shown beneficial effects in preclinical models and clinical trials. Alternatively, reprogramming TAMs towards a proinflammatory and tumouricidal phenotype has become an attractive strategy in immunotherapy. This work summarises the molecular wheelwork of macrophage biology and presents an overview of molecular strategies to repolarise TAMs in immunotherapy.

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