Human autoantibodies against a desmosomal protein complex with a calcium-sensitive epitope are characteristic of pemphigus foliaceus patients.

Pemphigus foliaceus (PF) patients have antibodies against a tightly, but noncovalently bound complex of polypeptides, which consists of desmoglein I (DGI) and other, possibly desmosomal, proteins. Most PF antibodies bind a calcium-sensitive epitope on this complex and chelation of calcium destroys the reactivity of these sera with the complex, but not the complex itself. The PF sera that do bind the desmosomal complex in the absence of calcium are those sera capable of binding denatured DGI on immunoblotting, and these same sera also immunoprecipitate only DGI when the desmosomal complex is dissociated with SDS. These findings demonstrate that autoantibodies against a complex of desmosome-associated proteins are characteristic of PF and define a calcium-sensitive conformational epitope on this complex.

Incidence and survival of childhood bone cancer in northern England and the West Midlands, 1981-2002.

There is a paucity of population-based studies examining incidence and survival trends in childhood bone tumours. We used high quality data from four population-based registries in England. Incidence patterns and trends were described using Poisson regression. Survival trends were analysed using Cox regression. There were 374 cases of childhood (ages 0-14 years) bone tumours (206 osteosarcomas, 144 Ewing sarcomas, 16 chondrosarcomas, 8 other bone tumours) registered in the period 1981-2002. Overall incidence (per million person years) rates were 2.63 (95% confidence interval (CI) 2.27-2.99) for osteosarcoma, 1.90 (1.58-2.21) for Ewing sarcoma and 0.21 (0.11-0.31) for chondrosarcoma. Incidence of Ewing sarcoma declined at an average rate of 3.1% (95% CI 0.6-5.6) per annum (P=0.04), which may be due to tumour reclassification, but there was no change in osteosarcoma incidence. Survival showed marked improvement over the 20 years (1981-2000) for Ewing sarcoma (hazard ratio (HR) per annum=0.95 95% CI 0.91-0.99; P=0.02). However, no improvement was seen for osteosarcoma patients (HR per annum=1.02 95% CI 0.98-1.05; P=0.35) over this time period. Reasons for failure to improve survival including potential delays in diagnosis, accrual to trials, adherence to therapy and lack of improvement in treatment strategies all need to be considered.

Identification of pemphigus vulgaris antigen extracted from normal human epidermis and comparison with pemphigus foliaceus antigen.

Immunoprecipitations of cultured keratinocyte extracts have shown that pemphigus vulgaris (PV) sera bind a polypeptide of 210,000 mol wt with disulfide-linked chains of 130,000 and 85,000 mol wt. To identify proteins in normal human skin recognized by PV antibodies, we performed immunoprecipitations of normal human epidermal extracts. All 22 PV sera tested immunoprecipitated a complex of polypeptides (PV complex) of 210,000, 130,000, and 85,000 mol wt, after reduction. One- and two-dimensional gel electrophoresis showed that the 130,000- and 85,000-mol-wt polypeptides of the PV antigen from both cultured keratinocytes and epidermis have identical charges and sizes. In addition to precipitating the PV complex, 14 of 22 PV sera also have antibodies to a calcium-sensitive epitope on a different complex of polypeptides (PF complex) which has previously been shown to be precipitated by all pemphigus foliaceus (PF) sera. The PF complex consists of polypeptides of 260,000, 160,000, 110,000, and 85,000 mol wt. Although the majority of PV sera also precipitate the PF complex, no PF sera precipitate the PV complex. Thus, PV and PF can be absolutely distinguished on a molecular level using the patients' autoantibodies. The PV and PF complexes, although distinct, have certain similarities. The 85,000-mol-wt polypeptide of each is identical. The 160,000-mol wt-peptide of the PF complex and the 130,000-mol-wt peptide of the PV complex have the same isoelectric point and both are capable of disulfide linkage to the 85,000-mol-wt polypeptide. The PV and PF complexes are closely related and may prove important in cell adhesion.

EACR-MRS conference on Seed and Soil: In Vivo Models of Metastasis.

New experimental tools are urgently required to better understand the metastatic process. The importance of such tools is underscored by the fact that many anti-cancer therapies are generally ineffective against established metastases. This makes a major contribution to the fact that metastatic spread is responsible for over 90% of cancer patient deaths. It was therefore timely that the recent "Seed and Soil: In Vivo Models of Metastasis" conference held in Berlin, Germany (27-29 of November 2017) aimed to give an in-depth overview of the latest research models and tools for studying metastasis, and to showcase recent findings from world-leading metastasis researchers. This Meeting Report summarises the major themes of this ground-breaking conference.

IgA immune complexes in patients with dermatitis herpetiformis occur in the absence of IgA rheumatoid factor.

Thirty to forty percent of patients with dermatitis herpetiformis (DH) have IgA-containing circulating immune complexes (IgA-CIC); however, the antigenic composition of these complexes as well as the role they play in the pathogenesis of DH are unknown. The failure to detect wheat protein in these IgA-CIC, despite the association of DH with gluten-sensitive enteropathy, suggests that the IgA-CIC in DH may be similar to those seen in the IgA nephropathies and represent IgA rheumatoid factor (RF)-IgG complexes. We have examined the sera of 32 patients with DH, 16 non-DH patients positive for RF by latex fixation, and 15 normal subjects for IgA and IgM RF using enzyme-linked immunosorbent assays (ELISAs) and for IgA-CIC using an anti-C3 ELISA. Thirteen of 16 (81%) latex fixation test-positive patients had IgA RF by ELISA and 15/16 (94%) had IgM RF by ELISA. The total amount of RF detected by the ELISA (IgA + IgM RF) correlated with the latex fixation titer (r = 0.678, p = 0.004) in these latex fixation-positive patients. Six of the 16 (38%) latex fixation-positive patients also were found to have IgA-CIC. Solid phase absorption using goat antihuman C3 decreased the levels of immune complexes but not the level of IgA RF, suggesting the IgA-CIC detected do not represent uncomplexed IgA RF. In contrast, although 12 of 31 (39%) patients with DH had IgA-CIC ranging in amount from 0.331-26.0 micrograms IgA/ml (nl less than 0.150 microgram IgA/ml), only 1 of 32 (3%) DH patients had detectable levels of IgA RF (7.0 micrograms IgA/ml, nl less than 2.0 micrograms IgA/ml). Low levels of IgM RF were found in 8/32 (25%) of patients with DH (1.1-1.6 micrograms IgM/ml, nl less than 1.0 microgram IgM/ml). These data document that IgA RF is not present in the sera of patients with DH independent of the presence or absence of IgA-CIC and that it is unlikely that the IgA-CIC present are IgA RF complexed with autologous IgG.

Drug-induced pemphigus: autoantibodies directed against the pemphigus antigen complexes are present in penicillamine and captopril-induced pemphigus.

Pemphigus is an autoimmune blistering disease characterized by circulating autoantibodies directed against the keratinocyte cell surface. The two variants, pemphigus foliaceus and pemphigus vulgaris, can be distinguished at the molecular level by immunochemical studies. The large majority of patients with pemphigus develop the disease spontaneously; however, there is a small group of patients who develop pemphigus after treatment with certain medications, of which penicillamine and captopril are the best documented. Most patients with drug-induced pemphigus have circulating and/or tissue bound epidermal cell surface autoantibodies; however, the molecular specificity of these autoantibodies has not been studied. We performed immunoprecipitation studies utilizing extracts of 125I-labeled suction blister epidermis and the sera of three patients with drug-induced pemphigus foliaceus (two due to penicillamine and one due to captopril) and one patient with captopril-induced pemphigus vulgaris. We found that the three patients with drug-induced pemphigus foliaceus had circulating autoantibodies that are directed against the pemphigus foliaceus antigen complex and that the one patient with drug-induced pemphigus vulgaris had circulating autoantibodies that are directed against the pemphigus vulgaris antigen complex. This study demonstrates that autoantibodies from drug-induced pemphigus patients have the same antigenic specificity, on a molecular level, as do autoantibodies from other pemphigus patients.

Human immunodeficiency virus in semen arises from a genetically distinct virus reservoir.

The reservoir of human immunodeficiency virus (HIV) in semen is unknown. Several lines of evidence suggest that semen HIV may not arise from the same reservoir of infection as peripheral blood. If true, the viral burden in the two compartments could be qualitatively and quantitatively different, a scenario of potentially profound significance for the design of effective strategies of treatment, disease monitoring, and infection containment. We report here that the ratio of infected to uninfected leukocytes in ejaculated semen specimens is highly discordant with paired blood samples, demonstrating that they derive from distinct populations of infected cells. In addition, infectious HIV was isolated from semen cells, but not from blood cells, of an individual on triple antiretroviral therapy; the absence of major resistance-conferring mutations in the semen virus indicates that it was replicating in isolation from the antiviral agents. The compartmentalization of blood and semen infection was further supported by genetic analysis of several infectious HIV clones isolated from semen cells and peripheral blood cells of another donor not on antiretroviral therapy. Protease gene sequence analyses revealed significant divergence of the two viral populations. These findings confirm the distinct compartmentalization of HIV in the semen of this study cohort, and support the concept that semen HIV arises from an isolated reservoir of infection that may function independently in the pathobiology of HIV disease.

Management of recurrent pelvic tumors.

The management of regional tumor recurrence in the pelvis traditionally has been a difficult problem for surgeons and oncologists. The only meaningful therapy for these patients is a potentially curative re-resection. The records and operative reports of 29 patients with regional pelvic tumor recurrence treated between 1981 and 1986 were reviewed. The operative procedures performed included three bowel resections, six abdominoperineal resections, eight pelvic exenterations, eight resections of tumor recurrence, and four conservative procedures. There was one operative death in this group. Significant morbidity was noted in the group but was clustered in a small number of patients operated on early in the series. The median follow-up in this series was 13 months (range, two to 51 months). Nineteen (65%) of the patients are surviving at a median follow-up of ten months (range, two to 51 months). The median survival (following resection) in the ten patients (35%) who died was 18 months. In 15 (52%) of the patients, a complete resection was performed. In this group, the survival is 80% with a median follow-up of 11 months. Seven (37%) are surviving with no evidence of disease. Palliation of symptoms occurred in 23 (79%) of the 29 patients. Radical resection of tumor recurrence in the pelvis can be performed with acceptable mortality and complication rates. This therapy should be considered for further clinical trials combining surgical and adjuvant therapy in patients with regional pelvic tumor recurrence.

Management of the urinary tract involved by recurrent cancer.

We present our experience from 1982 to the present in treating 33 patients with recurrent cancers (colorectal, 22; gynecologic, six; breast, two; melanoma, two; and lung, one) secondarily involving the genitourinary tract. All patients had severe symptoms that required palliation. Endoscopically placed stents relieved ureteral obstruction in 18 (75%) of 24 patients with widespread metastatic disease. Two patients required percutaneous nephrostomy tubes, and five required open operations. Good to excellent palliation was achieved in 23 of 24 patients. Mean survival in the group with diffuse metastases was 13 months (range, six to 29 months). Nine patients with localized recurrences underwent surgical procedures. For localized pelvic recurrences, total exenteration (with or without intraoperative radiotherapy) provided excellent palliation with low morbidity. At the time of this report, five of six such patients had no evidence of disease, and one had a small asymptomatic pelvic recurrence, with a mean follow-up of 13 months (range, five to 19 months).

Resection of cavoatrial renal cell carcinoma employing total circulatory arrest.

Intracaval extension of renal cell carcinoma to the right atrium is a life-threatening presentation that may result in fatal tricuspid valve obstruction or pulmonary embolization. From 1981 to 1989 we treated 10 patients with such extension of tumor, the last 7 of whom underwent resection in which hypothermic circulatory arrest was used. No postoperative deaths, myocardial infarctions, or strokes occurred. Four patients were alive with no evidence of disease at 4, 10, 16, and 39 months after resection, and 1 patient was alive with pulmonary and spine metastases at 34 months after resection. Two patients died of metastatic disease at 7 and 12 months. In the absence of diffuse metastatic disease, lymph-node involvement, or invasion of contiguous organs, radical resection of cavoatrial hypernephroma may result in excellent palliation and possibly a cure.

Semen leukocytes: friends or foes?

OBJECTIVE: To test the hypothesis that male reproductive tract leukocytes function in the elimination of abnormal spermatozoa from ejaculated semen. DESIGN: Semen specimens with > or = 2 x 10(6) nonspermatozoal cells/mL were examined for leukocytes and for mature sperm with ideal morphology. SETTING: Andrology laboratory of a Center of Assisted Reproductive Technology. RESULTS: Semen specimens with elevated concentrations of leukocytes contained a significantly higher frequency of sperm with ideal morphology than semen specimens with elevated numbers of immature germ cells and low numbers of leukocytes. CONCLUSIONS: The direct correlation between leukocyte density and sperm with ideal morphology supports the concept that sperm surveillance is a normal function of male reproductive tract leukocytes. Understanding such germ cell-leukocyte interactions may provide valuable new insights into immunologic control mechanisms in male reproductive tract tissues.

Breast cancer, side population cells and ABCG2 expression.

Recurrent metastatic breast cancer may arise in part due to the presence of drug resistant adult stem cells such as Side Population (SP) cells, whose phenotype has been demonstrated to be due to the expression of ABCG2. We hypothesised that SP may be identified in Fine Needle Aspirates (FNAs) and their presence may be determined by expression of ABCG2 in breast tumours. SP and non-side population cells (NSP) were isolated using dual wavelength flow cytometry combined with Hoechst 33342 dye efflux and analysed for expression of ABCG2 and chemoresistance. FNA samples used in SP analysis were matched with paraffin-embedded tissue which was used in immunohistochemical analysis to assess ABCG2 expression. Results were correlated to the pathobiology of the tumour. MCF7 and MDA-MB-231 cell lines contain SP cells. MCF7 SP have increased expression of ABCG2 and increased resistance to mitoxantrone compared to NSP cells. The presence of SP in FNAs were significantly associated with ER-negative (p=0.008) and with triple negative breast cancers (p=0.011) which were also found to have a significant increase in ABCG2 protein expression. ABCG2 transcript was detected in some but not all SP cell populations isolated from FNA samples.

Stability of singly hydrated silanone on silicon quantum dot surfaces: density functional simulations.

A key to understanding the optical characteristics of silicon quantum dots is the role of surface bonded species that introduce states to the band-gap. In particular, oxygen bonded in a silanone configuration is thought to be a source of shifts in emission during oxidation. We report the results of density-functional calculations examining the properties of such surface structures. We find single hydration of a simple, neutral silanone molecule leads to a barrierless conversion into a di-hydroxyl structure, and that similar processes are weakly activated on larger systems. However, we show that charging has a significant impact upon stability, with the attachment of an electron greatly increasing the barrier for converting silanone to di-hydroxyl termination. The relatively stable, negatively-charged silanone structures are predicted to lead to large red-shifts in the onset of optical absorption.