Patients with Minimal Hepatic Encephalopathy Show Altered Thermal Sensitivity and Autonomic Function.

Cirrhotic patients may experience alterations in the peripheral nervous system and in somatosensory perception. Impairment of the somatosensory system could contribute to cognitive and motor alterations characteristic of minimal hepatic encephalopathy (MHE), which affects up to 40% of cirrhotic patients. We assessed the relationship between MHE and alterations in thermal, vibration, and/or heat pain sensitivity in 58 cirrhotic patients (38 without and 20 with MHE according to Psychometric Hepatic Encephalopathy Score) and 39 controls. All participants underwent attention and coordination tests, a nerve conduction study, autonomic function testing, and evaluation of sensory thresholds (vibration, cooling, and heat pain detection) by electromyography and quantitative sensory testing. The detection thresholds for cold and heat pain on the foot were higher in patients with, than those without MHE. This hyposensitivity was correlated with attention deficits. Reaction times in the foot were longer in patients with, than without MHE. Patients with normal sural nerve amplitude showed altered thermal sensitivity and autonomic function, with stronger alterations in patients with, than in those without MHE. MHE patients show a general decrease in cognitive and sensory abilities. Small fibers of the autonomic nervous system and thermal sensitivity are altered early on in MHE, before large sensory fibers. Quantitative sensory testing could be used as a marker of MHE.

In vitro response to Candida albicans in cultures of whole human blood from young and aged donors.

Invasive infections with opportunistic fungi, such as Candida albicans, have become an increasing problem in aged adults in recent years. This work investigates the influence of human ageing on C. albicans recognition by toll-like receptors (TLRs), essential components of the innate immune system, using a cohort of 96 young (15-42 years) and aged (>70 years) human volunteers. No significant differences between aged and young donors were observed on (1) cell surface TLR2, TLR6 and TLR4 expression on lymphocytes, monocytes and granulocytes, (2) production of cytokines [IL-8, IL-1beta, IL-6, IL-10, tumour necrosis factor (TNF)-alpha and IL-12p70] and prostaglandin E(2) (PGE(2)) by whole human blood in response to C. albicans and (3) fungicidal activity of whole blood. A statistically significant higher titre of natural anti-C. albicans antibodies was found in plasma of volunteers between 80 and 95 years old when compared with other age groups, probably as a consequence of the increased levels of serum Ig that has been described in elderly subjects. Therefore, the results indicate that the increased susceptibility to C. albicans infections in the elderly is not a consequence of defects in TLRs expression or signalling, nor of an impaired fungicidal activity of blood.

Genetically engineered hybrid proteins from Parietaria judaica pollen for allergen-specific immunotherapy.

BACKGROUND: Despite the use of conventional allergen-specific immunotherapy in clinical practice, more defined, efficient, and safer allergy vaccines are required. OBJECTIVE: The aim of the study was to obtain hypoallergenic molecules by deleting B-cell epitopes, which could potentially be applied to Parietaria judaica pollen allergy treatment. METHODS: Three hybrid molecules (Q1, Q2, and Q3) derived from fragments of the 2 major P judaica pollen allergens, Par j 1 and Par j 2, were engineered by means of PCR. Hybrid structures were compared with their natural components by means of circular dichroism, and their biologic activities were compared by using T-cell proliferation assays. Their IgE-binding activity was determined with Western blotting, skin prick tests, and enzyme allergosorbent and ELISA inhibition tests. RESULTS: The hybrid proteins, especially Q2 and Q3, revealed significantly reduced IgE reactivity compared with the natural allergens, as well as with the whole P judaica extract. Furthermore, in vivo skin prick tests showed that the hybrid proteins had a significantly lower potency to induce cutaneous reactions than the whole P judaica extract. Two (Q1 and Q2) of the 3 hybrid proteins induced a comparable T-cell proliferation response as that produced by the whole extract and natural allergens. CONCLUSION: Considering its reduced anaphylactogenic potential, together with its conserved T-cell reactivity, the engineered Q2 protein could be used in safe and shortened schedules of allergen-specific immunotherapy against P judaica pollen allergy. CLINICAL IMPLICATIONS: Recombinant hybrid Q2 is able to induce T-cell proliferation, thus evidencing a potential therapeutic effect. Its reduced IgE-binding capacity envisages an excellent safety profile.

Human cytomegalovirus (HCMV)-specific CD4+ T lymphocyte response in AIDS patients with no past or current HCMV disease following HAART.

BACKGROUND: The incidence of Human Cytomegalovirus (HCMV) end-organ disease has dramatically decreased since the implementation of highly active antiretroviral therapies (HAARTs), but the precise immune mechanism whereby HCMV is controlled remains to be elucidated. OBJECTIVES: To investigate the effect of (HAART) on CD4+ T-cell immunity to HCMV in AIDS patients with no past or current HCMV disease. STUDY DESIGN: Seventeen patients were prospectively examined for CD4+ (CD45RO+ and CD45 RA+) T-cell counts (flow cytometry), HIV RNA load (Amplicor HIV test), HCMV leukoDNAemia and HCMV DNA in urine (nested PCR), lymphoproliferative response (LPR) to HCMV, phytohemagglutinin (PHA) and purified protein derived from Mycobacterium tuberculosis (PPD) by measurement of 5-bromo-2'-deoxyuridine incorporation to DNA (ELISA) and cytokine secretion (IFN-gamma, IL-4 and IL-10) by HCMV-stimulated peripheral blood mononuclear cell (PBMC) cultures (ELISA). RESULTS: Fifteen patients responded favorably to HAART (virologically, immunologically, or both). Of these, six patients presented LPR to HCMV at least once during follow-up, whereas most displayed detectable LPRs to PHA. IFN-gamma was detected at least once in supernatants of HCMV-stimulated PBMC cultures from 14 of the 17 patients. All but one patient tested negative for HCMV leukoDNAemia and HCMV DNA in urine, and none developed HCMV disease during the observation period. CONCLUSIONS: Control of HCMV replication and the absence of HCMV disease are not consistently associated with recovery and/or maintenance of LPR to HCMV in AIDS patients under HAART and with no prior HCMV disease. Whether detection of IFN-gamma by PBMCs upon HCMV antigenic stimulation may serve as a surrogate marker for protection against HCMV disease requires further investigation.

Elevated serum eotaxin levels in patients with inflammatory bowel disease.

OBJECTIVE: Eotaxin is a recently characterized chemokine with potent and selective chemotactic activity for eosinophils. Previous studies indicating that eosinophils accumulate and become activated in inflammatory bowel disease (IBD) led us to hypothesize that eotaxin is potentially involved in the pathophysiology of IBD and, therefore, that eotaxin would be increased in the serum of patients with IBD. The objective of this study was to test those assumptions. METHODS: We investigated 72 patients with IBD, 35 with ulcerative colitis, and 37 with Crohn's disease. A total of 27 patients had active and 45 inactive disease; 26 were receiving corticosteroids. Eotaxin serum levels were determined by solid phase sandwich ELISA. Lymphocytes, monocytes, and granulocyte subpopulations were determined in fresh blood samples with an automated autoanalyzer. RESULTS: Serum eotaxin levels were significantly higher in patients with Crohn's disease and in those with ulcerative colitis than in the control subjects (p < 0.0001). Patients with inactive Crohn's disease had significantly higher levels of eotaxin than patients with inactive ulcerative colitis (p < 0.05). We did not find significant differences for activity or inactivity of disease, nor for treatment with prednisone. A negative correlation (p < 0.05) was found between eotaxin serum level and eosinophil counts in peripheral blood in patients with Crohn's disease. CONCLUSIONS: There is an increased expression of eotaxin in IBD patients, suggesting that eotaxin may be involved in the pathogenesis of IBD. This increase is more accentuated in Crohn's disease and negatively correlates with the eosinophil number in peripheral blood. Our data support the increasing evidence that eosinophil are functionally involved in the pathophysiology of IBD.