Membrane proteins as diagnostic biomarkers and targets for new therapies

Membrane proteins, especially plasma membrane proteins, form one of the most interesting classes of proteins among disease biomarker candidates. Because of their localization on the surface of cells and organelles, membrane proteins also represent potential drug targets. In this review, developments in the characterization of membrane proteins and their role in the treatment of disease, in particular cancer treatment, are presented.     

Salivary gland tumours: 25 years of experience from a single institution in Croatia

IntroductionThe aim of this study was to determine the types, frequency, distribution, and demographic characteristics of salivary gland tumours in a large representative sample.Patients and methodsWe retrospectively analysed the medical records of 779 patients with tumours of the salivary glands surgically treated from 1985 to 2009 at a single institution.ResultsThere were 500 benign and 279 malignant tumours. The average age of patients with benign tumours was 50 years and of malignant salivary gland tumours 56 years. No differences in age and incidence of tumours existed between males and females. The majority of the tumours occurred in the parotid gland (509), followed by the minor salivary glands (212), the submandibular gland (51) and lastly, the sublingual gland (7). Minor salivary gland tumours occurred most frequently on the palate, the pleomorphic adenoma being the most frequent benign tumour type and the adenoid cystic carcinoma being the commonest malignant tumour. Tumours of the sublingual gland were rare, but all were malignant. Malignant tumours were more common in the minor salivary glands and the submandibular gland.ConclusionThis large study of salivary gland tumours in Croatia could improve our understanding of the significant differences in the global distribution of salivary gland tumours which have been reported.     

Mesenchymal stem cells attenuate liver fibrosis by suppressing Th17 cells – an experimental study

This study investigates molecular and cellular mechanisms involved in mesenchymal stem cell (MSC)‐mediated modulation of IL‐17 signaling during liver fibrosis. Mice received CCl₄ (1 μl/g intraperitoneally) twice/week for 1 month. MSCs (1 × 10⁶), or MSC‐conditioned medium (MSC‐CM), were intravenously injected 24 h after CCl₄ and on every 7th day. Liver fibrosis was determined by macroscopic examination, histological analysis, Sirius red staining, and RT‐PCR. Serum levels of cytokines, indoleamine 2,3‐dioxygenase (IDO), and kynurenine were determined by ELISA. Flow cytometry was performed to identify liver‐infiltrated cells. In vitro, CD4⁺ T cells were stimulated and cultured with MSCs. 1‐methyltryptophan was used for inhibition of IDO. MSCs significantly attenuated CCl₄‐induced liver fibrosis by decreasing serum levels of inflammatory IL‐17, increasing immunosuppressive IL‐10, IDO, and kynurenine, reducing number of IL‐17 producing Th17 cells, and increasing percentage of CD4⁺IL‐10⁺ T cells. Injection of MSC‐CM resulted with attenuated fibrosis accompanied with the reduced number of Th17 cells in the liver and decreased serum levels of IL‐17. MSC‐CM promoted expansion of CD4⁺FoxP3⁺IL‐10⁺ T regulatory cells and suppressed proliferation of Th17 cells. This phenomenon was completely abrogated in the presence of IDO inhibitor. MSCs, in IDO‐dependent manner, suppress liver Th17 cells which lead to the attenuation of liver fibrosis.     

Mechanistic insight into the dermal delivery from nanoparticle-coated submicron O/W emulsions

The influence of silica nanoparticle coating of negatively and positively charged submicron emulsion oil droplets on the dermal delivery of a lipophilic fluorescent probe, acridine orange 10-nonyl bromide (AONB) using an ex vivo porcine skin model is reported. The skin retention and depth of the penetration of AONB significantly increased (p ≤ 0.05) up to a skin depth of ～265 µm by nanoparticle coating of negative lecithin-stabilised emulsion oil droplets especially when nanoparticles were added from the water phase. The extent and depth of penetration of AONB incorporated into positively charged silica-coated oleylamine-stabilised emulsions significantly increased up to the upper dermis (～290 µm) with more pronounced effect by nanoparticle incorporation from the water phase of the control oleylamine emulsion. The permeation of AONB through full-thickness porcine skin was negligible (<0.12% of the topically applied dose). The skin penetration profile of AONB was well correlated to the more facilitated transport of the electrostatically bond silica–AONB complex compared to free AONB as one of the potential mechanisms of the improved delivery. The skin permeation of silica nanoparticles was negligible (<1 µg mL^?1 after a 6-h exposure time) which demonstrated the potential of nanoparticle-coated emulsions for topical targeting. © 2009 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 99:890–904, 2010     

Melanotic neuroectodermal tumour of infancy: Report of two cases and review of the literature

Melanotic neuroectodermal tumour of infancy (MNTI) is an uncommon tumour affecting predominantly the craniofacial bones of the newborn infants. The neural crest origin of the tumour has been confirmed. MNTI is generally accepted as a benign tumour despite of its rapid and locally infiltrative growth. Recurrence rate varies between 10% and 60%, and malignant behaviour has been reported in 6.5% of MNTIs. Systematic review of the literature revealed 445 MNTIs published between 1918 and 2010. We present additional two cases of MNTI from our Department, typical in all terms, which equals a total number of 447 reported cases. One of our cases revealed histological features consistent with malignant behaviour, but at present, 18 months after the surgical excision, there is no evidence of recurrence. Biological behaviour of MNTI cannot be predicted by gross or histologic characteristics, thus early diagnosis and careful follow-up after the complete surgical excision is required.     

Effect of pinealectomy on immune reactions in the rat

Non-inbred Wistar rats were pinealectomized at birth or in adult life, and tested for classical immune responses. Neonatal pinealectomy did not exert any notable effect on immune capacity of rats. On the other hand, rats pinealectomized at 6 weeks of age showed partial and transient impairment of immune potential. Arthus reactivity to bovine serum albumin was diminished and oedema of the skin less pronounced, and delayed reactions were reduced and of short duration. Slight delay in homograft rejection was noted. The incidence of allergic encephalomyelitis was diminished, and no clinical signs were observed. The cellular make-up of lymphoid tissues of pinealectomized adult rats was normal.     

IL-17 producing CD4 T cells mediate accelerated ischemia/reperfusion-induced injury in autoimmunity-prone mice

Elements of the innate and adaptive immune response have been implicated in the development of tissue damage after ischemic reperfusion (I/R). Here we demonstrate that T cells infiltrate the intestine of C57BL/6 mice subjected to intestinal I/R during the first hour of reperfusion. The intensity of the T cell infiltration was higher in B6.MRL/lpr mice subjected to intestinal I/R and reflected more severe tissue damage than that observed in control mice. Depletion of T cells limited I/R damage in B6.MRL/lpr mice, whereas repletion of B6.MRL/lpr lymph node-derived T cells into the I/R-resistant Rag-1^−/− mouse reconstituted tissue injury. The tissue-infiltrating T cells were found to produce IL-17. Finally, IL-23 deficient mice, which are known not to produce IL-17, displayed significantly less intestinal damage when subjected to I/R. Our data assign T cells a major role in intestinal I/R damage by virtue of producing the pro-inflammatory cytokine IL-17.     

A technique for detection of agglutinating activity of antilymphocytic serum using formalinized and trypan-blue-stained lymphocytes

This paper describes technical details of a micro-reaction for the in vitro detection of agglutinating potency of antilymphocytic serum produced in rabbits with chicken, rat and dog thymus cells. The titration of antilymphocytic serum includes the use of microtitre plastic plates and lymphocytes treated with formalin and stained with trypan blue stain. Formalinized and stained lymphocytes represent a stable antigen of long durability, and the application of those cells in leucoagglutination increases the accuracy and sensitivity of the reaction.