Opsonization of Apoptotic Cells by Autologous iC3b Facilitates Clearance by Immature Dendritic Cells, Down-regulates DR and CD86, and Up-regulates CC Chemokine Receptor 7

Immature dendritic cells (iDCs) do not mature after uptake of apoptotic cells and may play a role in the induction of peripheral tolerance to self antigens derived from apoptotic material. The integrins, αvβ3, αvβ5, and the scavenger receptor, CD36, have been shown to mediate uptake of apoptotic cells by iDCs. However, it is not known whether the complement system, also takes part in this process. In this study we investigated the ability of iDCs to bind to apoptotic cells opsonized by iC3b. Monocyte-derived dendritic cells were offered apoptotic Jurkat cells opsonized by autologous iC3b and labeled with 1,1′-dioctadecyl-3,3,3′,3′-tetramethyl-indocarbocyanineperchlorate. A significant increase (P < 0.001) in the amount of cleared apoptotic cells was seen at low ratios. Despite increased efficiency of uptake, interaction between iC3b-opsonized apoptotic cells and iDCs down-regulated the expression of major histocompatibility complex class II, CD86, CC chemokine receptor (CCR)2, CCR5, and β2-integrins (P < 0.001), and up-regulated expression of CCR7 (P < 0.001). In addition, iDC maturation responses to CD40L and lipopolysaccharide were significantly inhibited. We conclude that opsonization of apoptotic cells by iC3b induces tolerant iDCs that are able to migrate to lymph nodes

Epidemiology of the Microsporidium Nosema ceranae in Four Mediterranean Countries

Nosema ceranae is a highly prevalent intracellular parasite of honey bees’ midgut worldwide. This Microsporidium was monitored during a long-term study to evaluate the infection at apiary and intra-colony levels in six apiaries in four Mediterranean countries (France, Israel, Portugal, and Spain). Parameters on colony strength, honey production, beekeeping management, and climate were also recorded. Except for São Miguel (Azores, Portugal), all apiaries were positive for N. ceranae, with the lowest prevalence in mainland France and the highest intra-colony infection in Israel. A negative correlation between intra-colony infection and colony strength was observed in Spain and mainland Portugal. In these two apiaries, the queen replacement also influenced the infection levels. The highest colony losses occurred in mainland France and Spain, although they did not correlate with the Nosema infection levels, as parasitism was low in France and high in Spain. These results suggest that both the effects and the level of N. ceranae infection depends on location and beekeeping conditions. Further studies on host-parasite coevolution, and perhaps the interactions with other pathogens and the role of honey bee genetics, could assist in understanding the difference between nosemosis disease and infection, to develop appropriate strategies for its control

Leo Baeck Institute, New York : Bibliothek und Archiv Katalog Band I [Introduction] /

Manuscript draft with corrections of an English language introduction to the LBI Katalog 1970. Introduction to and overview of the collections, with notes and bibliography.Contains bibliography.HistorianSee also: Leo Baeck Institute New York, Bibliothek und Archiv; KatalogProcessed for digitization byBuber, MartinHolocaustdigitize

Incidence of and Risk Factors for Optic Disc Pallor Following Surgical Repair of Macular Hole

Pars Plana Vitrectomy (PPV) is a standard procedure during surgical repair of macular hole, and internal limiting membrane (ILM) peeling is often performed. ILM peeling is known to cause mechanical traumatic changes to the retinal nerve fiber layer. Anatomical changes of the macula and optic atrophy have been infrequently reported following ILM peeling, and a few mechanisms have been suggested. We examined the incidence of and risk factors for optic disc pallor following surgical repair of macular hole

On-chip multivariant COVID 19 photonic sensor based on silicon nitride double-microring resonators

Coronavirus disease 2019 (COVID-19) is a newly emerging human infectious disease that continues to develop new variants. A crucial step in the quest to reduce the infection is the development of rapid and reliable virus detectors. Here, we report a chip scale photonic sensing device consisting of a silicon-nitride double microring resonator (MRR) for detecting SARS-CoV-2 in clinical samples. The sensor is implemented by surface activation of one of the MRRs, acting as a probe, with DNA primers for SARS-CoV-2 RNA, whereas the other MRR is used as a reference. The performance of the sensor is determined by applying different amounts of SARS-CoV-2 complementary RNA. As will be shown in the paper, our device detects the RNA fragments at concentrations of 10 cp/μL and with sensitivity of 750 nm/RIU. As such, it shows a promise toward the implementation of label-free, small form factor, CMOS compatible biosensor for SARS-CoV-2, which is also environment, temperature, and pressure independent. Our approach can also be used for detecting other SARS-CoV-2 genes, as well as other viruses and pathogens