Immunoelectron microscopy provides evidence for the presence of mitochondrial heat shock 10-kDa protein (chaperonin 10) in red blood cells and a variety of secretory granules

Hsp10 (10-kDa heat shock protein, also known as chaperonin 10 or Cpn10) is a co-chaperone for Hsp60 in the protein folding process. This protein has also been shown to be identical to the early pregnancy factor, which is an immunosuppressive growth factor found in maternal serum. In this study we have used immunogold electron microscopy to study the subcellular localization of Hsp10 in rat tissues sections embedded in LR Gold resin employing polyclonal antibodies raised against different regions of human Hsp10. In all rat tissues examined including liver, heart, pancreas, kidney, anterior pituitary, salivary gland, thyroid, and adrenal gland, antibodies to Hsp10 showed strong labeling of mitochondria. However, in a number of tissues, in addition to the mitochondrial labeling, strong and highly specific labeling with the Hsp10 antibodies was also observed in several extramitochondrial compartments. These sites included zymogen granules in pancreatic acinar cells, growth hormone granules in anterior pituitary, and secretory granules in PP pancreatic islet cells. Additionally, the mature red blood cells which lack mitochondria, also showed strong reactivity with the Hsp10 antibodies. The observed labeling with the Hsp10 antibodies, both within mitochondria as well as in other compartments/cells, was abolished upon omission of the primary antibodies or upon preadsorption of the primary antibodies with the purified recombinant human Hsp10. These results provide evidence that similar to a number of other recently described mitochondrial proteins (viz., Hsp60, tumor necrosis factor receptor-associated protein- 1, P32 (gC1q-R) protein, and cytochrome c), Hsp10 is also found at a variety of specific extramitochondrial sites in normal rat tissue. These results raise important questions as to how these mitochondrial proteins are translocated to other compartments and their possible function(s) at these sites. The presence of these proteins at extramitochondrial sites in normal tissues has important implications concerning the role of mitochondria in apoptosis and genetic diseases.

Premature calvarial synostosis and epidermal hyperplasia (Beare-Stevenson syndrome-like anomalies) resulting from a P250R missense mutation in the gene encoding fibroblast growth factor receptor 3

We report on a patient with a severe premature calvarial synostosis and epidermal hyperplasia. The phenotype was consistent with that of a mild presentation of Beare-Stevenson syndrome but molecular analysis of the IgIII-transmembrane linker region and the transmembrane domain of the gene encoding the FGFR2 receptor, revealed wild-type sequence only. Subsequently, molecular analysis of the FGFR3 receptor gene identified a heterozygous P250R missense mutation in both the proposita and her mildly affected father. This communication extends the clinical spectrum of the FGFR3 P250R mutation to encompass epidermal hyperplasia and documents the phenomenon of activated FGFR receptors stimulating common downstream developmental pathways, resulting in overlapping clinical outcomes. (C) 2001 Wiley-Liss, Inc.

Vascular endothelial growth factor-B-deficient mice show impaired development of hypoxic pulmonary hypertension

To test the hypothesis that Vegf-B contributes to the pulmonary vascular remodelling, and the associated pulmonary hypertension, induced by exposure of mice to chronic hypoxia. Methods: Right ventricular systolic pressure, the ratio of right ventricle/[left ventricle+septum] (RV/[LV+S]) and the thickness of the media (relative to vessel diameter) of intralobar pulmonary arteries (o.d. 50-150 and 151-420 mum) were determined in Vegfb knockout mice (Vegfb(-/-); n=17) and corresponding wild-type mice (Vegfb(+/+); n=17) exposed to chronic hypoxia (10% oxygen) or housed in room air (normoxia) for 4 weeks. Results: In Vegfb(+/+) mice hypoxia caused (i) pulmonary hypertension (a 70% increase in right ventricular systolic pressure compared with normoxic Vegfb(+/+) mice; P

Destructive periodontitis lesions are determined by the nature of the lymphocytic response

It is now 35 years since Brandtzaeg and Kraus (1965) published their seminal work entitled Autoimmunity and periodontal disease. Initially, this work led to the concept that destructive periodontitis was a localized hypersensitivity reaction involving immune complex formation within the tissues. In 1970, Ivanyi and Lehner highlighted a possible role for cell-mediated immunity, which stimulated a flurry of activity centered on the role of lymphokines such as osteoclast-activating factor (OAF), macrophage-activating factor (MAF), macrophage migration inhibition factor (MIF), and myriad others. In the late 1970s and early 1980s, attention focused on the role of polymorphonuclear neutrophils, and it was thought that periodontal destruction occurred as a series of acute exacerbations. As well, at this stage doubt was being cast on the concept that there was a neutrophil chemotactic defect in periodontitis patients. Once it was realized that neutrophils were primarily protective and that severe periodontal destruction occurred in the absence of these cells, attention swung back to the role of lymphocytes and in particular the regulatory role of T-cells. By this time in the early 1990s, while the roles of interleukin (IL)-1, prostaglandin (PG) E-2, and metalloproteinases as the destructive mediators in periodontal disease were largely understood, the control and regulation of these cytokines remained controversial. With the widespread acceptance of the Th1/Th2 paradigm, the regulatory role of T-cells became the main focus of attention, Two apparently conflicting theories have emerged. One is based on direct observations of human lesions, while the other is based on animal model experiments and the inability to demonstrate IL-4 mRNA in gingival extracts. As part of the Controversy series, this review is intended to stimulate debate and hence may appear in some places provocative. In this context, this review will present the case that destructive periodontitis is due to the nature of the lymphocytic infiltrate and is not due to periodic acute exacerbations, nor is it due to the so-called virulence factors of putative periodontal pathogens.

The pathogenesis of oral lichen planus

Both antigen-specific and non-specific mechanisms may be involved in the pathogenesis of oral lichen planus (OLP). Antigen-specific mechanisms in OLP include antigen presentation by basal keratinocytes and antigen-specific keratinocyte killing by CD8(+) cytotoxic T-cells. Non-specific mechanisms include mast cell degranulation and matrix metalloproteinase (MMP) activation in OLP lesions. These mechanisms may combine to cause T-cell accumulation in the superficial lamina propria, basement membrane disruption, intra-epithelial T-cell migration, and keratinocyte apoptosis in OLP. OLP chronicity may be due, in part, to deficient antigen-specific TGF-beta1-mediated immunosuppression. The normal oral mucosa may be an immune privileged site (similar to the eye, testis, and placenta), and breakdown of immune privilege could result in OLP and possibly other autoimmune oral mucosal diseases. Recent findings in mucocutaneous graft-versus-host disease, a clinical and histological correlate of lichen planus, suggest the involvement of TNF-alpha, CD40, Fas, MMPs, and mast cell degranulation in disease pathogenesis. Potential roles for oral Langerhans cells and the regional lymphatics in OLP lesion formation and chronicity are discussed. Carcinogenesis in OLP may be regulated by the integrated signal from various tumor inhibitors (TGF-beta1, TNF-alpha, IFN-gamma, IL-12) and promoters (MIF, MMP-9). We present our recent data implicating antigen-specific and non-specific mechanisms in the pathogenesis of OLP and propose a unifying hypothesis suggesting that both may be involved in lesion development. The initial event in OLP lesion formation and the factors that determine OLP susceptibility are unknown.

Fate of swallowed interleukin 8 and TNF alpha and effect on the wistar rat gut

To evaluate the passage of cytokines through the gastrointestinal tract, we investigated the digestion of interleukin-8 (IL-8) and tumour necrosis factor α (TNFα), in vitro and in vivo, and their propensity to induce intestinal inflammation. We serially immuno-assayed IL-8 and TNFα solutions co-incubated with each of three pancreatin preparations at pH 4.5 and pH 8. We gavaged IL-8, TNFα and marker into 15 Wistar rats, and measured their faecal cytokine concentrations by ELISA and histologically examined their guts. IL-8 immunoreactivity was extinguished by all pancreatin preparations after 1 h of incubation at 37 °C. TNFα concentration progressively fell from 1 to 4 h with all enzyme preparations. Buffer control samples maintained their cytokine concentrations throughout incubation. No IL-8 or TNFα was detected in any rat faecal pellets. There was no significant proinflammatory effect of the gavaged cytokines on rat intestine. IL-8 and TNFα in aqueous solution could well be fully digested in the CF gut when transit time is normal and exogenous enzymes are provided, although cytokines swallowed in viscous sputum may be protected from such digestion. Copyright © 2011 Elsevier B.V. All rights reserved

Oral lichen planus: Causes, diagnosis and management

Oral lichen planus (OLP) is a chronic inflammatory disease of unknown etiology. In this paper we review the clinical and histological features of OLP, process of OLP diagnosis, causes of OLP, management of OLP patients and medical treatment of OLP lesions. Approximately 0.2 per cent OLP patients develop intra-oral carcinoma each year compared with approximately 0.005 per cent Australian adults. Possible mechanisms of increased oral cancer risk in OLP patients are presented. The aims of current OLP therapy are to eliminate mucosal erythema and ulceration, alleviate symptoms and reduce the risk of oral cancer. Patient education may improve the outcomes of OLP therapy and further reduce the risk of oral cancer in OLP patients. Although OLP may be diagnosed clinically, appropriate specialist referral is required for: (i) histological diagnosis; (ii) assessment of causative/exacerbating factors, associated diseases and oral cancer risk; (iii) patient education and management; (iv) medical treatment; and (v) long-term review and re-biopsy as required.