{"title":"Conversion of IgM to IgG by Lysates of Burkitt’s Lymphoma Cells","authors":"R. Bases, R. Lekhraj, Seema Gollamudi, E. Nieves","doi":"10.31038/tvi.2021111","DOIUrl":"https://doi.org/10.31038/tvi.2021111","url":null,"abstract":"The important landmark results of [1] showed that the IgM pentamer is an asymmetrical pentagon with an open groove that binds specific (AIM) protein. It contains one large gap. Other proteins could also bind in this way, perhaps leading to the evolution of single, ie. IgG, species. Here we examined the effects on IgM of protein and cell lysates of a leukemic cell line, CRL-1647. Lysates from 1.5 X l 08 cells were fractionated on Sepharose. The different size fractions were incubated with exogenous IgM to determine which ones could release immunopositive species, determined in Western blot analysis. IgG like proteins ~150 kDa and immunoreactive to IgG were released by fractions in the size range of 20 kDa to 5 kDa. When the fractions were incubated without exogenous IgM, IgG release was not found. Some IgG was found in the 150,000 MW size fraction with or without incubation, as expected, because the crude lysates contain endogeous IgG as well as IgM.","PeriodicalId":379971,"journal":{"name":"Trends in Vaccines and Immunology","volume":"81 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116388917","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The Trojan Horse Strategies of Parasites","authors":"A. Scovino, A. Trigueiros, A. Morrot","doi":"10.31038/tvi.2021121","DOIUrl":"https://doi.org/10.31038/tvi.2021121","url":null,"abstract":"Trends in Vaccines and Immunology, Volume 1(2): 1–2, 2021 The Trojan Horse is a legendary figure of a wooden horse used by the Greeks during the Trojan War to invade and destroy the Trojan city. Inside this seemingly harmless horse, supposedly sent as a sign of truce, were Greek warriors who at dusk, when the Trojan defenses were unarmed, took advantage to attack the city. This legendary figure can be used as an excellent analogy for the mechanisms some pathogens have adopted to invade the host and evade detection by the immune system. The ‘Trojan Horse Theory’ in immunology describes the ability of some microorganisms, using cells of the immune system itself as vectors, to escape the immune response.","PeriodicalId":379971,"journal":{"name":"Trends in Vaccines and Immunology","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130705585","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Do Pathogenic Chronic Infections Cause Host Senescence?","authors":"A. Scovino, A. Trigueiros, A. Morrot","doi":"10.31038/tvi.2021122","DOIUrl":"https://doi.org/10.31038/tvi.2021122","url":null,"abstract":"hemoglobin molecules (hemichromes), are recognized as antigens by autologous IgG antibodies and complement system. With the deposition of a critical density of antibodies and complement molecules, senescent red blood cells are recognized and eliminated [5]. The senescent red blood cells expose phosphatidylserine on the outer portion of their plasma membrane, a sign that indicates that the cell should be phagocytosed. In healthy cells this phospholipid is actively maintained in the cytoplasmic portion of the plasma membrane. Concomitantly, there is down-regulation of the CD47 molecule, a transmembrane protein whose normal expression indicates a non-phagocytic signal. The exposure of phosphatidylserine coupled with the reduction of CD47 expression stimulates phagocytosis and the elimination of these red blood cells [6]. In 2001, Bratosin [7] and colleagues described a process similar to apoptosis occurring in red blood cells, later called erythrosis [8]. Eryptosis has several similarities to apoptosis, regardless of the trigger, induction of an eripotic state usually involves extracellular calcium entry into the cell, caspase and calpain activation, which causes changes in membrane asymmetry, phosphatidylserine exposure and cell shrinkage. and membrane.","PeriodicalId":379971,"journal":{"name":"Trends in Vaccines and Immunology","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130452247","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}