Leukocyte oxygen radical production determines disease severity in the recurrent Guillain-Barré syndrome

<p>Abstract</p> <p>Background</p> <p>The recurrent Guillain-Barré syndrome (RGBS) is characterized by at least two GBS episodes with intervening remission. In a previous study of monophasic GBS, we reported that the magnitude of oxygen radical production ("respiratory burst") in peripheral blood leukocytes was inversely correlated to disease severity. The present study sought to establish a similar correlation in patients with RGBS.</p> <p>Methods</p> <p>Oxygen radical production in leukocytes was induced by formyl-Met-Leu-Phe (fMLF), Trp-Lys-Tyr-Met-Val-Met-NH₂(WKYMVM), or phorbol myristate acetate (PMA) and assessed by quantifying superoxide anion formed by the leukocyte NADPH oxidase.</p> <p>Results</p> <p>Disease severity, assessed using the MRC score, was negatively correlated to superoxide anion production triggered by fMLF or WKYMVM (p = 0.001 and 0.002, respectively; n = 10). Superoxide anion production also was significantly lower in RGBS patients with incomplete recovery after stimulation with fMLF (p = 0.004) or WKYMVM (p = 0.003).</p> <p>Conclusion</p> <p>We conclude that a lower respiratory burst in leukocytes is strongly associated with a severe course of RGBS.</p

Applications of Site-Specific Labeling to Study HAMLET, a Tumoricidal Complex of α-Lactalbumin and Oleic Acid

umor cells), and its tumoricidal activity has been well established.-acetylgalactosaminyltransferase II (ppGalNAc-T2) and further conjugated with aminooxy-derivatives of fluoroprobe or biotin molecules.We found that the molten globule form of hLA and αD-hLA proteins, with or without C-terminal extension, and with and without the conjugated fluoroprobe or biotin molecule, readily form a complex with OA and exhibits tumoricidal activity similar to HAMLET made with full-length hLA protein. The confocal microscopy studies with fluoroprobe-labeled samples show that these proteins are internalized into the cells and found even in the nucleus only when they are complexed with OA. The HAMLET conjugated with a single biotin molecule will be a useful tool to identify the cellular components that are involved with it in the tumoricidal activity

Respiratory burst and severity of demyelinating diseases

Multiple sclerosis (MS) and the Guillain-Barré syndrome (GBS) are tissue-specific inflammatory diseases of the central and the peripheral nervous system, respectively. A contemporary analysis infers that these are complex autoimmune disorders. Issues remaining to be solved are the factors determining susceptibility and the extreme variability in severity displayed by these diseases. The present study examines whether this variability is related to a basal function of the innate immune defence, regulating the intensity of inflammation. The severity of MS and GBS were evaluated by standard scoring systems, the Multiple Sclerosis Severity Score and the Medical Research Council Score. In addition, hard endpoints such as the need for intensive care unit treatment and the time to independent walking were used in the GBS, which was also evaluated for its proneness to recur. A possible relationship between these clinical parameters and the function of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase was examined. Phagocytes are endowed with this oxygen radical-forming enzyme, which reduces molecular oxygen to form several reactive oxygen species such as superoxide anion. This process, the “respiratory burst”, is a pivotal part of the innate defence against invading micro-organisms. The NADPH oxidase also has a regulatory influence upon the adaptive immune system. A lack of this enzyme elicits a human disease (Chronic Granulomatous Disease) characterized by extensive spontaneous inflammation, while recent studies in animal models imply that a deficiency of NADPH oxidase activity is related to the severity of organ-specific autoimmunity. The respiratory burst was assayed in the stationary (attack-free) phase of relapsing or slowly progressive multiple sclerosis (N = 60), in the monophasic GBS (N = 23), and in the recurrent GBS (RGBS) (N = 10), each with one age-matched healthy control analyzed simultaneously. The assay was performed by stimulating peripheral leukocytes by peptides, and measuring the amount of superoxide anion produced. The respiratory burst was markedly weaker in the group of GBS patients with a severe course (p = 0.0004 - 0.04). The same relationship was found in RGBS where the severity was expressed as degree of remission (p = 0.001 - 0.004) and individual recurrence proneness (interval between relapses and the time from onset to the second relapse, p = 0.006 - 0.03). An analogous relationship was also demonstrated between a weaker respiratory burst and a severe course of multiple sclerosis (p = 0.0035 - 0.04). In conclusion, the present study demonstrates that the intensity of the respiratory burst markedly contributes to the extreme variability in the severity of these demyelinating disorders. The innate immune system regulates the intensity rather than the susceptibility to these diseases. While loss of this system results in spontaneous autoinflammatory disease, we found that a low function predisposes for a more severe autoimmune disease. The mechanism may be a less effective control of infection and/or of the adaptive immune system

Oxygen radical production in leukocytes and disease severity in multiple sclerosis.

This study investigated the relationship between the formation of NADPH oxidase-dependent oxygen radicals in peripheral blood leukocytes (\u27respiratory burst\u27) and disease severity in patients with multiple sclerosis (MS). Oxygen radical production was induced by formyl-Met-Leu-Phe (fMLF), Trp-Lys-Tyr-Met-Val-Met-NH2 (WKYMVM) or phorbol myristate acetate (PMA) and was assessed by quantifying superoxide anion, i.e. the initial radical formed by the NADPH oxidase. Disease severity was evaluated using the Multiple Sclerosis Severity Score (MSSS). In patients with severe disease, the production of superoxide anion was significantly lower for all three inducers of radical formation (p=0.04-0.004). Our findings are supportive of a protective role of oxygen radicals in autoimmunity

The recurrent Guillain-Barre syndrome: a long-term population-based study

Objectives To describe a population-based material of patients with recurrent GuillainBarre syndrome (RGBS), examine the long time course, and search for factors predisposing to recurrence. Materials and methods We performed a follow-up study of the neurology and neurophysiology and a systematic study of the acute microbial serology of patients with RGBS. These parameters were compared with the results of a previous study of monophasic GBS. Results The patients with RGBS (n = 15) were retrieved from admissions of 229 patients with GBS during a 17-year period. They had 27 (median 3) episodes occurring at irregular intervals over decades. Of the 11 patients who accepted a follow-up examination, six were in full remission, and five had moderate sequelae. Nine had a demyelinating subtype, one had an axonal motor variant, and one patient with incomplete Miller Fisher syndrome had associated arachnoiditis. Two patients showed ultimate transition to a course similar to chronic inflammatory demyelinating polyneuropathy. Episodes were generally shorter in RGBS than in GBS, and an initial episode duratio

The recurrent Guillain-Barre syndrome: a long-term population-based study

Objectives To describe a population-based material of patients with recurrent GuillainBarre syndrome (RGBS), examine the long time course, and search for factors predisposing to recurrence. Materials and methods We performed a follow-up study of the neurology and neurophysiology and a systematic study of the acute microbial serology of patients with RGBS. These parameters were compared with the results of a previous study of monophasic GBS. Results The patients with RGBS (n = 15) were retrieved from admissions of 229 patients with GBS during a 17-year period. They had 27 (median 3) episodes occurring at irregular intervals over decades. Of the 11 patients who accepted a follow-up examination, six were in full remission, and five had moderate sequelae. Nine had a demyelinating subtype, one had an axonal motor variant, and one patient with incomplete Miller Fisher syndrome had associated arachnoiditis. Two patients showed ultimate transition to a course similar to chronic inflammatory demyelinating polyneuropathy. Episodes were generally shorter in RGBS than in GBS, and an initial episode duratio

Oxygen radical production and severity of the Guillain--Barré syndrome.

The NADPH oxidase-dependent formation of reactive oxygen species ("oxygen radicals") by phagocytic cells constitutes an important part of the innate immune defence against microorganisms. Recent studies in animal models imply that a deficient function of the NADPH oxidase may be linked to the development of autoimmunity, but a link between oxygen radical production and severity of autoimmune disease in humans has not been established. We have examined the oxygen radical production in peripheral blood leukocytes from patients with the Guillain-Barré syndrome (GBS). Leukocytes from GBS patients in a stationary phase 1-5 years after their acute episode were activated by the formyl peptide receptor (FPR) ligand formyl-Met-Leu-Phe (fMLF) or the closely related formyl peptide like receptor 1 (FPRL1) ligand Trp-Lys-Tyr-Met-Val-Met-NH2 (WKYMVM). The patients were dichotomized according to severity by 1) the requirement of intensive care unit treatment and 2) the ability to walk independently after 3 months. Our data show that the amount of superoxide release following challenge with either of the two agonists fMLF and WKYMVM was significantly lower in patients requiring intensive care unit treatment or unable to walk after 3 months. Results obtained with the global activator phorbol myristate acetate, as well as with fMLF in TNF alpha-primed leukocytes, suggested that the deficiency of oxygen radical production in patients with severe GBS was the result of a specific deficiency of radical production in response to FPR/FPRL1 ligands rather than an inherent deficiency of NADPH oxidase function