Monoclonal antibody U36, a suitable candidate for clinical immunotherapy of squamous-cell carcinoma,recognizes a CD44 isoform

At present, tumor-targeting with monoclonal antibodies (MAbs) is among the most promising novel adjuvant-therapy modalities for the treatment of patients with minimal residual disease of head-and-neck squamous-cell carcinoma (HNSCC). For this purpose we developed MAb U36, recognizing a 200-kDa antigen expressed on the outer cell surface of squamous-cell carcinomas and their normal counterparts. Clinical radioimmunoscintigraphy (RIS) and biodistribution studies have shown that the MAb-U36-defined antigen is a suitable target molecule for antibody-based therapy of head-and-neck cancer. In the present study we further characterized the antigen by cDNA cloning. The cDNA was isolated by expression cloning in COS-7 cells. Sequence analysis and database searching revealed that the MAb-U36-defined antigen is identical to the squamous-cell-specific CD44 splice variant epican. The epitope recognized by MAb U36 was mapped by screening overlapping synthetic peptides of the epican-specific region encoded by exon 7–11 (v3–v7), and appeared to be located in the v6 domain. The applicability of MAb U36 for targeting human tumors of various origin expressing the CD44v6 domain is discussed. © 1996 Wiley-Liss, Inc.     

Fumarylacetoacetase mutations in tyrosinaemia type I

Sixty-two hereditary tyrosinaemia type I (HT1) patients of various ethnic origins were classified clinically into acute, chronic, or intermediate phenotypes and screened for the 14 published causal mutations in the fumarylacetoacetase (FAH) gene. Restriction analysis of PCR amplified genomic DNA identified 74% of the mutated alleles. IVS12+5G→A, predominant in the French Canadian HT1 patients, was the most common mutation found in 32 alleles in patients from Europe, Pakistan, Turkey, and the United States. IVS6-1G→T, encountered in 14 alleles, was common in Central and Western Europe. There was an apparent “Scandinavian” 1009G→A combined splice and missense mutation (12 alleles), a “Pakistani” 192G→T splice mutation (11 alleles), a “Turkish” D233V mutation (6 alleles), and a “Finnish” or northern European W262X mutation (7 alleles). The remaining mutations were rare. Some of the mutations seem to predispose for acute and other for more chronic forms of HT1, but in our material no clearcut genotype phenotype correlation could be established. © 1996 Wiley-Liss, Inc.     

The relative risk of noncervical high-risk human papillomavirus-related (pre)malignancies after recurrent cervical intraepithelial neoplasia grade 3: A population-based study

Women with cervical intraepithelial neoplasia grade 3 (CIN3) have a long-lasting increased risk for noncervical high-risk human papillomavirus (hrHPV)-related (pre)malignancies. The aim of our study was to estimate this risk in women with recurrent CIN3 compared to women without a history of CIN3 and women with a single episode of CIN3. Women with a CIN3 diagnosis between 1990 and 2010 were obtained from the Dutch Pathology Registry (PALGA) and matched with a control group of women without CIN3. Analysis has been conducted in a subset of women with recurrent CIN3, defined as reoccurrence minimally 2 years post-treatment. Cases of noncervical hrHPV-related (pre)malignancies of the anus, vulva, vagina and oropharynx were identified until 2015 and incidence rate ratios (IRRs) were estimated. Then, 1,797 women with recurrent CIN3 were included with a median age of 34 years (range 18–76) and 31,594 person-years of follow-up. Women with recurrent CIN3 had an increased risk of developing noncervical hrHPV-related (pre)malignancies compared to women without CIN3 with an IRR of 25.96 (95%CI 6.32–106.58). The IRR was 2.48 (95% CI 1.87–3.30) compared to women with a single episode of CIN3. Studies on posttreatment follow-up and prophylactic hrHPV vaccination are warranted.     

Subjective dysphagia in older care home residents: A cross-sectional,multi-centre point prevalence measurement

Background

Dysphagia has been found to be strongly associated with aspiration pneumonia in frail older people. Aspiration pneumonia is causing high hospitalization rates, morbidity, and often death. Better insight in the prevalence of (subjective) dysphagia in frail older people may improve its early recognition and treatment.

Objective

First, to assess the prevalence of subjective dysphagia in care home residents in the Netherlands. Second, to assess the associations of subjective dysphagia with potential risk factors of dysphagia.

Design

Retrospective data-analysis of a cross-sectional, multi-centre point prevalence measurement.

Setting

119 care homes in the Netherlands.

Participants

Data of 8119 care home residents aged 65 years or older were included and analyzed.

Methods

Subjective dysphagia was assessed by a resident's response to a dichotomous question with regard to experiencing swallowing problems. If a resident was not able to respond (e.g. residents with dementia or aphasia), the question was answered by the ward care provider, or the resident's file was consulted for registered swallowing complaints and/or dysphagia. Several residents’ data were collected: gender, age, (number of) diseases, the presence of malnutrition, the Care Dependency Scale score, and the body mass index.

Results

Subjective dysphagia was found in 751 (9%) residents. A final model for subjective dysphagia after multivariate backward stepwise regression analysis revealed eight significant variables: age (B −0.022), Care Dependency Scale score (B −0.985), ‘malnutrition’ (OR 1.58; 95% CI 1.31–1.90), ‘comorbidity’ (OR 1.07; 95% CI 1.01–1.14), and the disease clusters ‘dementia’ (OR 0.55; 95% CI 0.45–0.66), ‘nervous system disorder’ (OR 1.55; 95% CI 1.20–1.99), ‘cardiovascular disease’ (OR 0.81; 95% CI 0.67–0.99) and ‘cerebrovascular disease/hemiparesis’ (OR 1.74; 95% CI 1.45–2.10).

Conclusion

It seems justified to conclude that subjective dysphagia is a relevant care problem in older care home residents in the Netherlands. Care Dependency Scale score, ‘malnutrition’, and the disease clusters ‘dementia’, ‘nervous system disorder’, and ‘cerebrovascular disease/hemiparesis’ were associated with the presence of subjective dysphagia in this study. Age, ‘comorbidity’ and ‘cardiovascular disease’ showed very small influence.     

Coexistence of foam cells and hypocholesterolemia in mice lacking the ABC transporters A1 and G1

The concept that macrophages can become foam cells as a result of a disturbed balance between the uptake of cholesterol from lipoproteins and cholesterol efflux is generally accepted. ABCA1 and ABCG1 are two cholesterol transporters that may act sequentially to remove cellular cholesterol, but currently their combined role in vivo is unknown. We report here that targeted disruption of both ABCA1 and ABCG1 in mice, despite severe plasma hypocholesterolemia, leads to massive lipid accumulation and foam cell formation of tissue macrophages. A complete ablation of cellular cholesterol efflux in vitro is observed, whereas in vivo macrophage-specific reverse cholesterol transport to the feces is markedly decreased. Despite the massive foam cell formation of tissue macrophages, no lipid accumulation was observed in the vascular wall, even in mice of 1 year old, indicating that the double knockout mice, possibly because of their hypocholesterolemia, lack the trigger to attract macrophages to the vessel wall. In conclusion, even under hypocholesterolemic conditions macrophages can be converted into foam cells, and ABCA1 and ABCG1 play an essential role in the prevention of foam cell formation.     

Protein kinase C α and ε phosphorylation of troponin and myosin binding protein C reduce Ca2+ sensitivity in human myocardium

Previous studies indicated that the increase in protein kinase C (PKC)-mediated myofilament protein phosphorylation observed in failing myocardium might be detrimental for contractile function. This study was designed to reveal and compare the effects of PKCα- and PKCε-mediated phosphorylation on myofilament function in human myocardium. Isometric force was measured at different [Ca²⁺] in single permeabilized cardiomyocytes from failing human left ventricular tissue. Activated PKCα and PKCε equally reduced Ca²⁺ sensitivity in failing cardiomyocytes (ΔpCa₅₀ = 0.08 ± 0.01). Both PKC isoforms increased phosphorylation of troponin I- (cTnI) and myosin binding protein C (cMyBP-C) in failing cardiomyocytes. Subsequent incubation of failing cardiomyocytes with the catalytic subunit of protein kinase A (PKA) resulted in a further reduction in Ca²⁺ sensitivity, indicating that the effects of both PKC isoforms were not caused by cross-phosphorylation of PKA sites. Both isozymes showed no effects on maximal force and only PKCα resulted in a modest significant reduction in passive force. Effects of PKCα were only minor in donor cardiomyocytes, presumably because of already saturated cTnI and cMyBP-C phosphorylation levels. Donor tissue could therefore be used as a tool to reveal the functional effects of troponin T (cTnT) phosphorylation by PKCα. Massive dephosphorylation of cTnT with alkaline phosphatase increased Ca²⁺ sensitivity. Subsequently, PKCα treatment of donor cardiomyocytes reduced Ca²⁺ sensitivity (ΔpCa₅₀ = 0.08 ± 0.02) and solely increased phosphorylation of cTnT, but did not affect maximal and passive force. PKCα- and PKCε-mediated phosphorylation of cMyBP-C and cTnI as well as cTnT decrease myofilament Ca²⁺ sensitivity and may thereby reduce contractility and enhance relaxation of human myocardium.