Maternal deprivation of rat pups increases clinical symptoms of experimental autoimmune encephalomyelitis at adult age

Maternal deprivation of neonatal animals has been shown to induce long-lasting changes in the reactivity of the neuroendocrine system. The aim of the present study was to investigate whether maternal deprivation also affects susceptibility to immune-mediated diseases such as experimental autoimmune encephalomyelitis (EAE) in adult life.To this end, 9-day-old rat pups were subjected to a short-lasting maternal deprivation for a period of 24 h. At the age of 8 weeks, we induced EAE in these rats by immunization with myelin basic protein (MBP) in complete Freund's adjuvant. Our data demonstrate that short-lasting maternal deprivation induces a marked increase in the severity of EAE in the animals in later life. The histopathological evaluation of spinal cord and cerebellum corresponded with the observed differences in clinical symptoms of EAE. Moreover, neonatal maternal deprivation affects macrophage functioning at adult age. In contrast, no differences were observed in in vitro mitogen- and MBP-induced cytokine production by splenocytes. LPS-induced corticosterone release did not differ either between maternally deprived and control animals. We conclude that short-lasting neonatal maternal deprivation of rat pups has long-lasting consequences for macrophage activity and for susceptibility to the inflammatory autoimmune disease EAE.     

The role of cyclo-oxygenase 1 and 2 activity in prostaglandin E(2) secretion by cultured human adult microglia: implications for Alzheimer's disease

Microglial cyclo-oxygenase (COX) expression is considered to be important in the pathogenesis of Alzheimer's disease (AD) and, therefore, constitutes a key target for therapeutic intervention. We investigated the influence of AD plaque associated factors on COX-1 and COX-2 expression and activity in adult human microglial cells in vitro. COX-2 immunoreactivity and mRNA were induced by lipopolysaccharide (LPS), not by AD plaque associated cytokines interleukin (IL)-1alpha, IL-1beta, IL-6, tumor necrosis factor (TNF)-alpha, or amyloid (A)beta(1-42). To assess functional COX activity, the release of PGE(2) into the culture medium was determined. LPS and also arachidonic acid (AA) dose-dependently stimulated PGE(2) release. The effects of AA are independent from induction of COX mRNA expression, or of de novo protein synthesis. No effects of either plaque-associated cytokines or Abeta(1-42) on PGE(2) secretion were seen, even when cells were co-stimulated with AA, to provide enough substrate. COX isotype selective inhibitors were used to discern relative contributions of COX-1 and COX-2 activities to microglial PGE(2) secretion. COX-2 and in part COX-1-selective inhibitors inhibited LPS-induced PGE(2) secretion, whereas the AA-induced PGE(2) secretion was reduced by COX-1-selective inhibitors only. Apparently, adult human microglia in vitro (1) constitutively express COX-1, and (2) do not express COX-2 upon exposure to either Abeta or plaque associated cytokines. In the light of microglial COX activity as a potential therapeutical target in AD, the data presented in this study suggest that classical NSAIDs, rather than selective COX-2 inhibitors, are more potent in reducing microglial prostaglandin secretion.     

Neuroinflammation and Alzheimer disease: clinical and therapeutic implications

In Alzheimer disease brains, the amyloid plaques are closely associated with a locally induced, nonimmune-mediated, chronic inflammatory response without any apparent influx of leukocytes from the blood. The present findings indicate that in cerebral A beta diseases (Alzheimer disease, Down syndrome, hereditary cerebral hemorrhage with amyloidosis-Dutch type), the clinical symptoms are determined to a great extent by the site of inflammatory response. It was found that the formation of the amyloid-microglia complex seems to be a relatively early pathogenic event that precedes the process of severe destruction of the neuropil. The idea that inflammation is implicated in Alzheimer pathology has received support from the epidemiologic studies indicating that the use of anti-inflammatory drugs can prevent or retard the Alzheimer disease process. In this contribution, we review the relationship between inflammation and clinical manifestation and the opportunities for anti-inflammatory treatments in Alzheimer disease.     

Frequent detection of human papillomavirus 16 E2-specific T-helper immunity in healthy subjects.

The incidence of genital human papillomavirus (HPV) infections is high in young, sexually active individuals. Most infections are cleared within 1 year after infection. The targets for the cellular immune response in this process of viral clearance remain to be identified, but the expression pattern of the E2 protein in early infection and low-grade cervical intraepithelial neoplasia renders this early protein a candidate antigen. Therefore, we studied the HPV16 E2-specific T-cell responses in more detail. Very strong proliferative responses against one or more peptide-epitopes derived from this antigen can be found in peripheral blood mononuclear cell cultures of approximately half of the healthy donors. Additional analysis revealed that at least a majority of these responses represent reactivity by memory CD4(+) T-helper (Th) 1-type cells capable of secreting IFN-gamma on antigenic stimulation. Interestingly, all of the E2 peptides against which strong responses were detected are clustered in the key functional domains of the E2 protein, which are conserved to considerable extent between HPV types. This suggests that HPV16 E2-specific Th memory may be installed through encounter with HPV types other than HPV16. Indeed, one HPV16 E2-specific Th clone was found to cross-react against homologuous peptides from other HPV types, but three other Th clones failed to show similar cross-reactivity. Therefore, part of the HPV16 E2-specific Th memory may relate to previous encounter of other HPV types, whereas the majority of the immune repertoire concerned is most likely established through infection with HPV16 itself. Our data are the first to reveal that the T-cell repertoire of healthy donors can contain particularly high frequencies of E2-specific memory Th cells and suggest that boosting of this immunity can be used for preventive and therapeutic vaccination against HPV-induced lesions.     

Dialysate partitioning in the Genius batch hemodialysis system: effect of temperature and solute concentration

BACKGROUND: The Genius batch system contains a 75-L closed reservoir from which fresh dialysate is extracted at the top, and to which spent dialysate is returned at the bottom. In vivo studies have demonstrated that almost the entire amount of dialysate can be used before contamination of fresh with spent dialysate occurs. The question is raised whether density differences cause this separation, and what the relative contributions of temperature and solute content are. METHODS: As patient substitute, a container filled with dialysate was loaded with various amounts of urea. Temperature differences between spent and fresh dialysate were imposed by not heating the dialysate at the outlet line from the dialyzer (A), heating the outlet to obtain continuously equal temperatures at inlet and outlet (B), or to temperatures as in vivo (C). With a dialysate flow set at 300 mL/min, urea is not expected at the inlet before 250 minutes. RESULTS: With a urea concentration of 33 mg/dL, urea contamination at the dialysate inlet line occurred after 185 +/- 20 (A), 122 +/- 11 (B), and 175 +/- 12 minutes (C) of dialysis, whereas with 67 mg/dL, this happened at 219 +/- 5 (A), 162 +/- 11 (B), and 202 +/- 8 minutes (C). With 100 and 150 mg/dL, urea contamination appeared at 224 +/- 2 (A) and 204 +/- 14 minutes (B), and 227 +/- 5 (A) and 232 +/- 3 minutes (B), respectively. CONCLUSION: Both temperature differences between spent and fresh dialysate and solute content of spent dialysate contribute to dialysate partitioning in the Genius dialysis system.     

Diabetes-related symptoms and negative mood in participants of a targeted population-screening program for type 2 diabetes: The Hoorn Screening study

Objective: To determine the level of diabetes-related symptom distress and its association with negative mood in subjects participating in a targeted population-screening program, comparing those identified as having type 2 diabetes vs. those who did not. Research design and methods: This study was conducted within the framework of a targeted screening project for type 2 diabetes in a general Dutch population (age 50–75 years). The study sample consisted of 246 subjects, pre-selected on the basis of a high-risk profile; 116 of whom were subsequently identified as having type 2 diabetes, and 130 who were non-diabetic subjects. Diabetes-related symptom distress and negative mood was assessed ∼2 weeks, 6 months, and 12 months after the diagnosis of type 2 diabetes, with the Type 2 Diabetes Symptom Checklist and the Negative well-being sub scale of the Well-being Questionnaire (W-BQ12), respectively. Results: Screening-detected diabetic patients reported significantly greater burden of hyperglycemic (F=6.0, df=1, p=0.015) and of fatigue (F=5.3, df=1, p=0.023) symptoms in the first year following diagnosis type 2 diabetes compared to non-diabetic subjects. These outcomes did not change over time. The total symptom distress (range 0–4) was relatively low for both screening-detected diabetic patients (median at ∼2 weeks, 6 months, and 12 months; 0.24, 0.24, 0.29) and non-diabetic subjects (0.15, 0.15, 0.18), and not significantly different. No average difference and change over time in negative well-being was found between screening-detected diabetic patients and non-diabetic subjects. Negative well-being was significantly positive related with the total symptom distress score (regression coefficient β=2.86, 95% CI 2.15–3.58). Conclusions: The screening-detected diabetic patients were bothered more by symptoms of hyperglycemia and fatigue in the first year following diagnosis type 2 diabetes than non-diabetic subjects. More symptom distress is associated with increased negative mood in both screening-detected diabetic patients and non-diabetic subjects.     

The unfolded protein response is activated in Alzheimer’s disease

Alzheimers disease (AD) is, at the neuropathological level, characterized by the accumulation and aggregation of misfolded proteins. The presence of misfolded proteins in the endoplasmic reticulum (ER) triggers a cellular stress response called the unfolded protein response (UPR) that may protect the cell against the toxic buildup of misfolded proteins. In this study we investigated the activation of the UPR in AD. Protein levels of BiP/GRP78, a molecular chaperone which is up-regulated during the UPR, was found to be increased in AD temporal cortex and hippocampus as determined by Western blot analysis. At the immunohistochemical level intensified staining of BiP/GRP78 was observed in AD, which did not co-localize with AT8-positive neurofibrillary tangles. In addition, we performed immunohistochemistry for phosphorylated (activated) pancreatic ER kinase (p-PERK), an ER kinase which is activated during the UPR. p-PERK was observed in neurons in AD patients, but not in non-demented control cases and did not co-localize with AT8-positive tangles. Overall, these data show that the UPR is activated in AD, and the increased occurrence of BiP/GRP78 and p-PERK in cytologically normal-appearing neurons suggest a role for the UPR early in AD neurodegeneration. Although the initial participation of the UPR in AD pathogenesis might be neuroprotective, sustained activation of the UPR in AD might initiate or mediate neurodegeneration.