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In fungi, β-Glucans (bG), composed of glucose, perform various functions, such as compo-nents of extracellular matrices and energy reserves. The interest in its study is due to its im-munomodulatory and antitumor properties. The present review comprehensively presents the molecular interactions behind these effects that are still limitedly understood, so there is a knowledge gap related to their mechanisms and effects in humans. A relevant aspect found through the nonsystematic exploration of the literature is the ligand-receptor dynamics be-tween: β-Glucans (bG) and molecular pattern receptors (PRRs) key in their recognition, such as Dectin1 and the membrane-type complement receptor. 3 (CR3), separately and together. Thus, bG, Dectin1 and CR3 were shown to orchestrate a cellular immune response. It is es-sential to recognize the need for: a specific molecular weight monitoring standard and further research on β-glucan receptors, such as CR3. [ABSTRACT FROM AUTHOR]

In the face of SARS-CoV-2 infection, an uncontrolled and unregulated response of the innate immune system can cause local and multisystem organ damage, which is characteristic of patients admitted to hospitals and who die from this virus. See some of the factors involved in the severe pathological pictures of this infection, mainly in men, in articles published between 2010 and 2021 and specialized books. Research shows that age, gender, race, and blood group (specifically A), coupled with factors such as immunosenescence and comorbidities, are crucial in the severity of the disease. Finally, it is suggested that, although men and women have the same probability of becoming ill with COVID-19, men are more likely to die because they have more ACE2 receptors in plasma, greater esterase activity, produce more proinflammatory cytokines, and respond differently to hormones (testosterone favors the innate immune response more while estrogens favor the adaptive one) and to the effects of dopamine inhibitors, involved in the inflammatory response. In addition, androgen hormones regulate the TMPRSS receptor and induce metalloproteases involved in adhesion and fibrotic processes. [ABSTRACT FROM AUTHOR]

Introduction: Cnidarians depend on innate immunity for protection against both their own and external biological agents. It consists of three main immunological processes: 1) immune recognition, 2) intracellular signaling, and 3) effector response. Objective: To critically review current knowledge of the molecular repertoire involved in the immune response in cnidarians, its role in symbiosis, and possible biotechnological applications. Methods: We used keywords such as immunity, and immunological recognition in cnidarians, in the NCBI, Scielo and Google Scholar databases, for the last decade. Results: Cnidarian immune recognition consists of molecular pattern receptors and responses such as the mobilization of molecules to the site of infection, microbial ingestion, and the formation of molecules that activate signaling cascades. The signaling phase involves translation mediators that activate transcriptional genes and intracellular signaling cascades that initiate defenses. Effector responses include surface layer mucus, antimicrobial peptides, reactive oxygen species, and the cellular response mediated by phagocytosis. Conclusions: Immunity in Cnidaria is mediated by complex defense mechanisms composed of pathogen recognition receptors, intracellular signaling pathways, effector cells and molecules responsible for pathogen elimination, and recognition of symbionts. There is a potential for toxin compounds useful as antimicrobial molecules. [ABSTRACT FROM AUTHOR]

Infection with the new coronavirus (sArs-cov2) is a challenge for any immune system since, as it is a novel entity, individuals have no immunological memory and it has meant a paradigm shift in the way of addressing viral infections. our immune system is capable of orchestrating an innate response that can contain the virus through Pattern recognition receptors (Prrs) and a large number of cytokines such as InF-γ, Il-1, Il-6, Il-12, Il-18. and tGFβ as well as chemokines (ccl2, cXcl10, cXcl9 and Il-8) that are capable of activating the inflammosome to organize the inflammatory response and, on the other hand, to activate the acquired immunity with activity of lymphocytes with th1-type response and B lymphocytes that produce functional antibodies against the virus. however, it has been evidenced in a group of patients, especially the elderly or patients with comorbidities, that the number of lymphocytes may be lower, which is correlated with greater morbidity and fatality. on the contrary, children have a greater quantity of lymphocytes, which could explain why the disease is less severe in the pediatric age. [ABSTRACT FROM AUTHOR]

Innate immunity and cellular adaptive immunity are considered the first lines of defense against fungal infections in humans. Most of the major opportunistic mycoses occur in individuals with defects in innate and/or cellular adaptive immunity. Morbidity and mortality rates associated with infections caused by fungal pathogens are high, and prevention, diagnosis, and treatment of these infections remain somewhat difficult. Altered immune function is thought to cause an increased susceptibility to fungal infections in the host and determine the severity and characteristics of the infection. Non-specific cellular immunity mediated by macrophages, neutrophils, and NK lymphocytes provides efficient protection against fungal infections in healthy individuals. For this reason, the increase in systemic fungal infections is undoubtedly related to the increase in the number of patients with congenital or acquired immunodeficiencies. There is increasing clinical and experimental evidence that antigen-specific cellular immunity plays an important role in host protection against fungi. [ABSTRACT FROM AUTHOR]

Infection with the new coronavirus (sArs-cov2) is a challenge for any immune system since, as it is a novel entity, individuals have no immunological memory and it has meant a paradigm shift in the way of seeing viral infections. our immune system is capable of orchestrating an innate response that can contain the virus through Pattern recognition receptors (Prrs) and a large number of cytokines such as InF-γ, Il-1, Il-6, Il-12, Il-18. and tGFβ as well as chemokines (ccl2, cXcl10, cXcl9 and Il-8) that are capable of activating the inflammosome to organize the inflammatory response and, on the other hand, to activate the acquired immunity with activity of lymphocytes with th1-type response and B lymphocytes that produce functional antibodies against the virus. however, it has been evidenced in a group of patients, especially the elderly and / or with comorbidities, that the number of lymphocytes may be lower, which is correlated with greater morbidity and fatality. on the contrary, children have a greater quantity of lymphocytes, which could explain why there is less severity in the pediatric age. [ABSTRACT FROM AUTHOR]

Infantile obesity constitutes an important health problem at the present time that is experiencing an increment in the entire world. In obese people the excess of white adipic tissue generates a low degree chronic inflammatory response, when increasing the secretion of inflammatory molecules and diminishing the anti-inflammatory ones-- adiponectin and cytosine--. At the moment it is recognized that the adipic tissue possesses implications in the innate immunity because in the adipose cell, Toll-like receptors are expressed and drive to a cascade of intracelular signaling when being activated, and the beginning of an inflammatory response is promoted this way. Due to the importance of the topic, in this work this cellular process and its influence in the beginning and the perpetuation of the proinflamatory state in the obesity is described. [ABSTRACT FROM AUTHOR]

Candida albicans is a comensal microorganism that under certain circumstances is able to transform into a pathogen. This ability to switch constitute a virulence factor that C. albicans uses to invade and spread. The innate immune system recognize the different forms of C. albicans activating receptors (PRRs) that recognize PAMPs or conserved molecular patterns. The most impor tant immune cells are macrophages and neutrophils that generate an effector response through phagocytosis and oxidative burst against C. albicans. Dendritic cells express the most of PRRs involved in the recognition of C. albicans activating the cytokines synthesis forward to a TH1 (induced by INF tipo1, IL-12, INFγ), Treg (induced by TGFβ, IL-10) y TH17 (induced by IL- 23, IL6) immune response. Epithelial cells not only constitute a physical barrier against C. albicans, but they are crucial in the first recognition of this microorganism. Through a biphasic response these cells differentially activate pathways that determine a no cytokine response when blastoconidia (commensal form) is present and an inflammatory response in presence of hyphae (pathogenic form). C. albicans develops immune evasive mechanism. This complex host-fungi interaction determines if the host will eradicate the infection or if this microorganism will invade the host, expressing it virulence. [ABSTRACT FROM AUTHOR]

Introduction: Infertility is a clinical and social problem affecting 13% to 15% of couples around the world. One of its causes is the pelvic inflammatory disease, induced by several infectious agents, Chlamydia trachomatis standing out amongst them. This infectious agent has molecular mechanisms modulating the host immune response and producing changes in the infected cell to allow it to survive, casing a chronic immunological system response, with consequent permanent inflammation and sequelae such as cicatrices and obstruction of the fallopian tubes. This review was aimed at updating knowledge regarding the immune-biology of infection caused by Chlamydia trachomatis and its relationship with infertility. Materials and methods: A literature review was made using PubMed/MEDLINE, Science Direct and Ovid databases from January 1995 to January 2012, including review articles and clinical studies. Results: It is currently held that immunomodulation characterizing infection caused by Chlamydia trachomatis, the inflammatory mediators implicated in the immune response and possible (though little studied) host genetic susceptibility are closely related to the genesis of tubal infertility. Conclusion: Infertility caused by Chlamydia trachomatis has its origin in a host's immunological response and this infections agent's modulation leading to chronic inflammation, healing and obstruction of the fallopian tubes. [ABSTRACT FROM AUTHOR]

Therapeutic vaccination of chronic infectious diseases has been extensively explored because of its possible contribution to their eradication. In particular, therapeutic vaccination of hepatitis B virus chronic infections is especially interesting since this disease is characterized by a sustained necro-inflammatory process of the liver that may evolve into more severe conditions including cirrhosis and hepatocellular carcinoma. The basic role of the immune system in the healing process of this chronic infection suggests that it offers a favorable setting for immunotherapeutic treatments, either spontaneously or as a result of antiviral therapy. However, no vaccine has been able to cure this or any other chronic infection in spite of the large number of vaccine candidates tested. The knowledge of the liver as a lymphoid organ and the limited advances of therapeutic vaccination demand more thorough analyses within the rationale of current vaccine candidates. In the last ten years there has been an increased knowledge of innate immunity and intra- and extra-hepatic signaling mechanisms, to support a rational design of vaccine strategies. The high costs and low effectiveness of conventional treatments, and the large amount of chronic carrier patients for this virus, indicate a favorable setting for the development of immunotherapeutic products against chronic hepatitis B. It is possible to predict that adjuvant strategies that take into account the properties of the liver as a lymphoid organ would have an impact in the development of this new field of therapeutic vaccines. [ABSTRACT FROM AUTHOR]

Bony fishes possess immune systems capable of humoral and cellular responses, both innate and specific; essentially, defense systems of teleost fishes have the same components as vertebrate defense systems, which they antecede evolutionarily. This review describes the components of teleost immune systems, emphasizing particularities present in fish but not in mammals, whose defensive mechanisms are known in greater detail. The study of fish immunity is relevant for both basic and applied purposes. On the one hand, knowledge of fish immunology is important to elucidate the origin and evolution of the immune system of higher vertebrates. On the practical side, although some commercial vaccines are available to protect fishes against viruses and bacteria, rising knowledge of fish immunology would enable increasing the yield and inocuity of aquaculture, through the development of novel methods of immune stimulation and vaccination. [ABSTRACT FROM AUTHOR]

The scallop Argopecten purpuratus is characterized by variations in some immunity parameters of the hemolymph when faced with the pathology known as mantle retraction. A relationship between the hemocytic reaction of encapsulatien and this pathology was established with light and electronic transmission microscopy. The quantitative comparison of the number of hemocytes, the phagocytic capacity of these cells in the presence of yeasts, and the cytotoxicity of the hemolymph in specimens with and without mantle retraction showed that the hemocytes and serum of scallops with mantle retraction respond differently. When mantle retraction is observed, the number of circular hemocytes decreases. In exchange, the serum increases its cytotoxic capacity when faced with erythrocytes. On the other hand, when the yeasts were previously incubated in this serum, the phagocytic capacity of the hemocytes decreased. The results show that the pathology known as mantle retraction in the scallop determines a significant variation in cellular immunity and the humoral components of the hemolymph, and an encapsulation response in the presence of coalescent bodies in the mantle. [ABSTRACT FROM AUTHOR]

The great resistance to infectious process in skin is due, in part, to molecules named antimicrobial peptides (AMPs) that constitutes an important component responsible of mechanisms in innate immunity in this tissue. In this review the classification, structure and function of these molecules are shown, besides the information about the resistance mechanisms and their therapeutic potential. [ABSTRACT FROM AUTHOR]

The gene MBL codifies for a protein that has a role in innate immunity by activating the complement system as well as recruiting macrophages and proinflammatory chemokines. Studies performed around the world have associated susceptibility/resistance to infectious, autoimmune and cardiovascular diseases, with deficient alleles of MBL. However, many of these studies remain inconclusive because of the rarity of these alleles. We have previously shown that the frequency of defective allele B in the islands of Lake Titicaca is the highest in the world. Now, we want to evaluate the frequency of this allele in Amazonian areas that are more prone to infectious diseases. We have genotyped 94 individuals from Andoas-Loreto and found a higher frequency of the defective allele B compared to other populations (but lower than that from Lake Titicaca). This frequency and the high exposure to tropical diseases make the population of Andoas interesting to study the role of the MBL variants in the development these diseases. [ABSTRACT FROM AUTHOR]

The respiratory tract is one of the main apparatus which is in daily contact with a wide variety of microorganisms, however, only on a few occasions is infection establish because of its innate immune response. Respiratory tract epithelial cells play a very important role in avoiding infectious agent colonization of the lungs, since this kind of cell can recognize microbial molecules through very specialized receptors such as Toll-like. Moreover these cells posses a broad variety of molecules which are related to local immunity. Respiratory tract epithelial cells are capable of producing several chemokines, antimicrobial peptides and other pro-inflammatory molecules. [ABSTRACT FROM AUTHOR]