Incunabular Immunological Events in Prion Trafficking

While prions probably interact with the innate immune system immediately following infection, little is known about this initial confrontation. Here we investigated incunabular events in lymphotropic and intranodal prion trafficking by following highly enriched, fluorescent prions from infection sites to draining lymph nodes. We detected biphasic lymphotropic transport of prions from the initial entry site upon peripheral prion inoculation. Prions arrived in draining lymph nodes cell autonomously within two hours of intraperitoneal administration. Monocytes and dendritic cells (DCs) required Complement for optimal prion delivery to lymph nodes hours later in a second wave of prion trafficking. B cells constituted the majority of prion-bearing cells in the mediastinal lymph node by six hours, indicating intranodal prion reception from resident DCs or subcapsulary sinus macrophages or directly from follicular conduits. These data reveal novel, cell autonomous prion lymphotropism, and a prominent role for B cells in intranodal prion movement

Follicular Dendritic Cell-Specific Prion Protein (PrPc) Expression Alone Is Sufficient to Sustain Prion Infection in the Spleen

Prion diseases are characterised by the accumulation of PrPSc, an abnormally folded isoform of the cellular prion protein (PrPC), in affected tissues. Following peripheral exposure high levels of prion-specific PrPSc accumulate first upon follicular dendritic cells (FDC) in lymphoid tissues before spreading to the CNS. Expression of PrPC is mandatory for cells to sustain prion infection and FDC appear to express high levels. However, whether FDC actively replicate prions or simply acquire them from other infected cells is uncertain. In the attempts to-date to establish the role of FDC in prion pathogenesis it was not possible to dissociate the Prnp expression of FDC from that of the nervous system and all other non-haematopoietic lineages. This is important as FDC may simply acquire prions after synthesis by other infected cells. To establish the role of FDC in prion pathogenesis transgenic mice were created in which PrPC expression was specifically “switched on” or “off” only on FDC. We show that PrPC-expression only on FDC is sufficient to sustain prion replication in the spleen. Furthermore, prion replication is blocked in the spleen when PrPC-expression is specifically ablated only on FDC. These data definitively demonstrate that FDC are the essential sites of prion replication in lymphoid tissues. The demonstration that Prnp-ablation only on FDC blocked splenic prion accumulation without apparent consequences for FDC status represents a novel opportunity to prevent neuroinvasion by modulation of PrPC expression on FDC

M cell-depletion blocks oral prion disease pathogenesis

Many prion diseases are orally acquired. Our data show that after oral exposure, early prion replication upon follicular dendritic cells (FDC) in Peyer's patches is obligatory for the efficient spread of disease to the brain (termed neuroinvasion). For prions to replicate on FDC within Peyer's patches after ingestion of a contaminated meal, they must first cross the gut epithelium. However, the mechanism through which prions are conveyed into Peyer's patches is uncertain. Within the follicle-associated epithelium overlying Peyer's patches are microfold cells (M cells), unique epithelial cells specialized for the transcytosis of particles. We show that following M cell-depletion, early prion accumulation upon FDC in Peyer's patches is blocked. Furthermore, in the absence of M cells at the time of oral exposure, neuroinvasion and disease development are likewise blocked. These data suggest M cells are important sites of prion uptake from the gut lumen into Peyer's patches

Mechano-Electric Feedback in the Fish Heart

Mechanoelectric feedback (MEF) describes the modulation of electrical activity by mechanical activity. This may occur via the activation of mechanosensitive ion channels (MSCs). MEF has not previously been investigated in fish ventricular tissue even though fish can greatly increase ventricular end diastolic volume during exercise which should therefore provide a powerful mechanical stimulus for MEF.When the ventricles of extrinsically paced, isolated working trout hearts were dilated by increasing afterload, monophasic action potential (MAP) duration was significantly shortened at 25% repolarisation, unaltered at 50% repolarisation and significantly lengthened at 90% repolarisation. This observation is consistent with the activation of cationic non-selective MSCs (MSC(NS)s). We then cloned the trout ortholog of TRPC1, a candidate MSC(NS) and confirmed its presence in the trout heart.Our results have validated the use of MAP technology for the fish heart and suggest that, in common with amphibians and mammals, MEF operates in fish ventricular myocardium, possibly via the activation of mechanosensitive TRPC1 ion channels

Lactate dehydrogenase-5 (LDH-5) overexpression in non-small-cell lung cancer tissues is linked to tumour hypoxia, angiogenic factor production and poor prognosis

Lactate dehydrogenase-5 (LDH-5) catalyses the reversible transformation of pyruvate to lactate, having a principal position in the anaerobic cellular metabolism. Induction of LDH-5 occurs during hypoxia and LDH-5 transcription is directly regulated by the hypoxia-inducible factor 1 (HIF1). Serum LDH levels have been correlated with poor prognosis and resistance to chemotherapy and radiotherapy in various neoplastic diseases. The expression, however, of LDH in tumours has never been investigated in the past. In the present study, we established an immunohistochemical method to evaluate the LDH-5 overexpression in tumours, using two novel antibodies raised against the rat muscle LDH-5 and the human LDH-5 (Abcam, UK). The subcellular patterns of expression in cancer cells were mixed nuclear and cytoplasmic. In direct contrast to cancer cells, stromal fibroblasts were reactive for LDH-5 only in a minority of cases. Serum LDH, although positively correlated with, does not reliably reflect the intratumoral LDH-5 status. Lactate dehydrogenase-5 overexpression was directly related to HIF1alpha and 2alpha, but not with the carbonic anhydrase 9 expression. Patients with tumours bearing high LDH-5 expression had a poor prognosis. Tumours with simultaneous LDH-5 and HIF1alpha (or HIF2alpha) overexpression, indicative of a functional HIF pathway, had a particularly aggressive behaviour. It is concluded that overexpression of LDH-5 is a common event in non-small-cell lung cancer, can be easily assessed in paraffin-embedded material and provides important prognostic information, particularly when combined with other endogenous markers of hypoxia and acidity

Current challenges facing the assessment of the allergenic capacity of food allergens in animal models

Food allergy is a major health problem of increasing concern. The insufficiency of protein sources for human nutrition in a world with a growing population is also a significant problem. The introduction of new protein sources into the diet, such as newly developed innovative foods or foods produced using new technologies and production processes, insects, algae, duckweed, or agricultural products from third countries, creates the opportunity for development of new food allergies, and this in turn has driven the need to develop test methods capable of characterizing the allergenic potential of novel food proteins. There is no doubt that robust and reliable animal models for the identification and characterization of food allergens would be valuable tools for safety assessment. However, although various animal models have been proposed for this purpose, to date, none have been formally validated as predictive and none are currently suitable to test the allergenic potential of new foods. Here, the design of various animal models are reviewed, including among others considerations of species and strain, diet, route of administration, dose and formulation of the test protein, relevant controls and endpoints measured

Prion Uptake in the Gut: Identification of the First Uptake and Replication Sites

After oral exposure, prions are thought to enter Peyer's patches via M cells and accumulate first upon follicular dendritic cells (FDCs) before spreading to the nervous system. How prions are actually initially acquired from the gut lumen is not known. Using high-resolution immunofluorescence and cryo-immunogold electron microscopy, we report the trafficking of the prion protein (PrP) toward Peyer's patches of wild-type and PrP-deficient mice. PrP was transiently detectable at 1 day post feeding (dpf) within large multivesicular LAMP1-positive endosomes of enterocytes in the follicle-associated epithelium (FAE) and at much lower levels within M cells. Subsequently, PrP was detected on vesicles in the late endosomal compartments of macrophages in the subepithelial dome. At 7–21 dpf, increased PrP labelling was observed on the plasma membranes of FDCs in germinal centres of Peyer's patches from wild-type mice only, identifying FDCs as the first sites of PrP conversion and replication. Detection of PrP on extracellular vesicles displaying FAE enterocyte-derived A33 protein implied transport towards FDCs in association with FAE-derived vesicles. By 21 dpf, PrP was observed on the plasma membranes of neurons within neighbouring myenteric plexi. Together, these data identify a novel potential M cell-independent mechanism for prion transport, mediated by FAE enterocytes, which acts to initiate conversion and replication upon FDCs and subsequent infection of enteric nerves

Kosmetiikkamyyjän opas

Tämä työn tavoitteena oli luoda kosmetiikkamyyjälle opas. Opas on tarkoitettu kosmetiikan vähittäismyymälöissä ja tavarataloissa toimiville myyjille ja kosmetologiopiskelijoille. Opas on selkeä ja helppolukuinen kokonaisuus kosmetiikan myyntityöstä. Teoriaosuudessa käsitellään myyntityötä yleensä. Myyjän toimivuus myyjänä liittyy ammattitaitoon tehdä myyntityötä. Myyjän on ymmärrettävä mistä myyntityö koostuu ja kyvystä käyttää itseään välineenä myynnin tekemisessä. Myyntityöhön liittyy olennaisesti hyvä asiakaspalvelu. Myyjän on osattava toimia asiakkaan toivomalla tavalla ja usein sitäkin paremmin. Teoriaosuudessa käsitellään myyntityötä yleensä ja erilaisia myyntitekniikoita. Myyntiprosessin vaiheet käydään läpi tarkasti, koska niiden ymmärtäminen on myyjälle tärkeätä. Asiakkaan saapuminen liikkeeseen ja asiakkaan tervehtiminen ovat myyntitilanteen perusta. Tarvekartoitus, myyntikeskustelu, lisämyynti ja kaupanpäättäminen ovat myyntiprosessin tärkeimpiä ja vaikeimpia vaiheita ja ne on käytävä läpi oikeassa järjestyksessä. Nämä myyntiprosessin osa-alueet on myyntityössä hoidettava asiakkaan edut huomioiden. Viimeisessä luvussa esitellään huippumyyjä, mitä ominaisuuksia huippumyyjä omaa ja miten tullaan huippumyyjäksi. Kaikilla on mahdollisuus huipulle tässäkin lajissa. Se vaatii harjoittelua, sinnikkyyttä ja asiaan paneutumista sekä ennen kaikkea erinomaista motivaatiota. Varsinainen kosmetiikkamyyjän opas on erillinen kirjanen. Siinä käydään läpi käytännönläheisesti koko myyntiprosessi, asiakkaan vastaanottaminen, tarvekartoitus, tuote-esittely, kaupan päättäminen, lisämyynti ja asiakkaan poistuminen. Lopuksi esitellään huippumyyjän ominaisuudet.A guidebook for cosmetics salesperson The objective of this thesis was to create a guidebook for cosmetics salesperson. The guidebook is aimed at shop assistants in retail sales and department stores as well as beauty therapy students. The guidebook is clear and easy to read giving a comprehensive picture of cosmetics sales. The theory part of this thesis covers retail sales in general. How to work as a salesperson is linked to professional capability. The salespersons must understand the sales process as a whole and part of the process. One essential part of the sales process is great customer care. A salesperson must understand how to act the way customers are expecting – and often even better. The theory part studies different sales method. The stages of the sales process are covered in detail, because the understanding of these stages is essential for a salesperson. The customers’ arrival to the shop and greeting the customers are the basic elements in a sales situation. Mapping the customer needs, conversing with the client, generating additional sales and closing the sale are the most important and difficult parts in the sales process. These four parts of the sales process must always be based on customer benefits. The last chapter introduces top salespersons: what are their qualities and how to become a top salesperson. This demands a lot of training, persistence and delving into the subject as well as great motivation. The guidebook itself is a separate booklet. The booklet goes through the whole sales process in practise starting from the customers’ arrival, going through mapping the needs, introducing the products and closing the sale, as well as generating additional sales and dealing with customers leaving the shop. Top salespersons and their qualities are introduced at the end of the booklet