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PubMed1997

Effects of non-steroidal antiallergic eyedrops on the complement-mediated histamine release from human cells.

Leukocytes from ten allergic patients (five allergic to dust-mites and five allergic to pollen) were treated with N-acetyl aspartyl glutamic acid (NAAGA) 4.9%, disodium cromoglycate (DSCG) 2%, lodoxamide (LODO) 1%, and levocabastine (LEVO) 0.5% (concentrations representing the pharmaceutical eyedrop preparations) for 20 minutes. Degranulation was then induced with Complement (rHu5Ca). Histamine was measured in the supernatant with ELISA. LODO and LEVO were inactive in blocking histamine released from human cells, and paradoxical unexpected effects were found with these two agents. They both induced significant histamine release in almost 100% of the samples. DSCG was able to block histamine release in seven patients out of nine (ranging between 5 and 34%). NAAGA was the most active agent on human cells and was able to block basophil degranulation in nine patients out of nine (inhibition ranging between 4 and 66% of total histamine pool).

Allergens↗
PubMed2005

Comparative analysis of genetically engineered immunodeficient mouse strains as recipients for human myoblast transplantation.

The development of an optimized animal model for the in vivo analysis of human muscle cells remains an important goal in the search of therapy for muscular dystrophy. Here we examined the efficiency of human myoblast xenografts in three distinct immunodeficient mouse models. We found that different conditioning regimes used to provoke host muscle regeneration (i.e., cardiotoxin versus cryodamage) had a marked impact on xenograft success. Tibialis anterior muscle of Rag2-, Rag-/gammac-, and Rag-/gammac-/C5- mice was treated by cardiotoxin or cryodamage, submitted to enzymatic digestion, and analyzed by cytofluorometry to quantitate inflammatory cells. Human myoblasts were injected into pretreated muscles from immunodeficient recipients and the cell engraftment evaluated by immunocytochemistry, 4-8 weeks after transplantation. Donor cell differentiation and dispersion within the host muscles was also investigated. Host regeneration in cardiotoxin-treated mice was accompanied by a higher inflammatory cell infiltration when compared to that induced by cryodamage. Accordingly, when compared to the cardiotoxin group, more human myogenic cells were found after cryodamage. When the distinct immunodeficient mice were compared, we found that the alymphoid strain lacking the complement component C5 (Rag-/gammac-/C5- mice) was the most efficient host for human muscle xenografts, when compared with C5(+)Rag-/gammac- mice or Rag- mice. Our results demonstrate that cryolesion-conditioned muscles of Rag-/gammac-/C5- mice provide the best environment for long-term in vivo human myoblast differentiation, opening the way for a novel approach to study the pathophysiology of human muscle disorders.

Animals↗
PubMed2001

Production of chemokines in vivo in response to microbial stimulation.

Members of the chemokine gene superfamily are known to play a central role in leukocyte extravasation; however, their involvement in acute inflammation in response to micro-organisms has not yet been well studied. We have therefore investigated the role of murine macrophage-inflammatory protein (muMIP) 1alpha and muMIP-2 in the inflammatory response mounted against the bacteria Salmonella enteritidis and the Sacchromyces cerevisiae cell wall component, zymosan. Leukocyte extravasation was monitored in murine s.c. air pouches. Both agonists induced accumulation of leukocytes in a dose- and time-dependent manner, with the response peaking after 4 h and declining thereafter. The inflammatory exudate comprised mainly neutrophils; however, an increase in eosinophil accumulation was also observed in response to zymosan. The production of both muMIP-1alpha and muMIP-2 increased with time in response to both the agonists, although production was more sustained in response to the bacteria. Prior treatment of mice with neutralizing Abs against muMIP-1alpha or muMIP-2, either alone or in combination, failed to attenuate the accumulation of leukocytes in response to the agonists. In contrast, the anti-muMIP-2 Abs significantly inhibited leukocyte recruitment in response to S. enteritidis in complement-deficient mice. Taken together, these data show that while muMIP-1alpha and muMIP-2 are produced in response to phagocytosis of micro-organisms in s.c. tissue, under these circumstances components of the complement pathway appear to play a dominant role in the recruitment of neutrophils.

Animals↗
PubMed2000

Drusen associated with aging and age-related macular degeneration contain proteins common to extracellular deposits associated with atherosclerosis, elastosis, amyloidosis, and dense deposit disease.

Age-related macular degeneration (AMD), a blinding disorder that compromises central vision, is characterized by the accumulation of extracellular deposits, termed drusen, between the retinal pigmented epithelium and the choroid. Recent studies in this laboratory revealed that vitronectin is a major component of drusen. Because vitronectin is also a constituent of abnormal deposits associated with a variety of diseases, drusen from human donor eyes were examined for compositional similarities with other extracellular disease deposits. Thirty-four antibodies to 29 different proteins or protein complexes were tested for immunoreactivity with hard and soft drusen phenotypes. These analyses provide a partial profile of the molecular composition of drusen. Serum amyloid P component, apolipoprotein E, immunoglobulin light chains, Factor X, and complement proteins (C5 and C5b-9 complex) were identified in all drusen phenotypes. Transcripts encoding some of these molecules were also found to be synthesized by the retina, retinal pigmented epithelium, and/or choroid. The compositional similarity between drusen and other disease deposits may be significant in view of the recently established correlation between AMD and atherosclerosis. This study suggests that similar pathways may be involved in the etiologies of AMD and other age-related diseases.

Aging↗
PubMed1975

Physicochemical characterization of chemotatic lymphokines produced by human T and B lymphocytes.

Ostensibly pure populations of T and B lymphocytes were separated from peripheral human blood by a sequential rosetting method. These cells, and mononuclear leukocyte (MNL) cell preparations (60 to 85% T cells), were cultured in vitro and the supernatants of these cultures were assayed for chemotactic lymphokine (CTX) activity. B lymphocytes were activated to produce CTX by binding erythrocytes sensitized with antibody and complement (EAC) to their C3 receptors and phytohemagglutinin (PHA) stimulation of isolated T cells was used to produce T cell-derived CTX. Sephadex G-100 gel filtration chromatography of supernatants obtained from T and B cell cultures showed that both cell types produce a CTX of approximate molecular weight 12,500 daltons. This result is identical to that previously obtained in characterizing the CTX produced by buffy coat leukocytes. Isoelectric focusing of lymphocyte supernatants and chemotactically active Sephadex G-100 fractions showed that the CTX produced by B cells and PHA-stimulated MNL contained two peaks of lymphokine activity, a major peak at pH 10.1 and a minor peak at pH 5.6. Additionally, these studies show that the chemotactic complement peptide C5a has an isoelectric point of pH 8.7 and is antigenically distinct from T and B cell-derived CTX, although relatively homogenous by gel filtration, contain two isoelectrically distinct species. In addition, these findings suggest that T and B cells although possessing different membrane receptors and requiring different mechanisms of activation to initiate lymphokine synthesis, produce lymphokines with identical physiocochemical properties.

Animals↗
PubMed2003

[Protein content in blood plasma and its changes in patients of the neurological critical care unit].

Twelve blood plasma proteins were studied in 120 patients with isolated traumatic and nontraumatic cerebral hemorrhage. At all stages of the study a marked imbalance of blood proteins occurred which was independent of the etiological factor. Patients with craniocerebral trauma exhibited the phenomenon of the atypical response manifesting with low concentration of acute-phase proteins. The levels of the complement component C5 and transferrin in patients with cerebral vascular aneurysm rupture are shown diagnostically significant while follow-up of blood transtiretin can show the trend in the metabolic processes in patients with cerebral hemorrhage in critical condition.

Acute-Phase Proteins↗
PubMed1992

[Usefulness of the prevention of oxygen radical damage in the critical patient using the parenteral administration of reduced glutathione in high doses].

A hyperproduction of Oxygen Free Radicals (FRO) is frequently observed during stress, anoxia, hyperbarism and may worsen the clinical conditions of intensive care patients. The hyperproduction of FRO may be reduced by antioxidants. The glutathione (GSH) is frequently associated with organic antioxidant protective systems. Forty patients receiving a continuous infusion of 70 mg/Kg/die of GSH were compared with forty patients not receiving GSH; the patients in both groups were randomized for age, sex, and pathology. Some parameters which are indirect indexes of FRO hyperproduction were chosen: ethane in the expired air, plasma malondialdehyde, fibrinopeptide A and C5 activated complement fraction, also the erythrocyte membrane deformability was investigated. The results obtained in the group receiving GSH were compared with the control group and a significative difference was found indicating a reduced FRO production. These interesting results need more trials in order to confirm a real GSH involvement in the antioxidant organic protection. In any case the supplementation with antioxidants in the therapy of intensive care patients can be regarded as an interesting means to improve their clinical conditions.

Adolescent↗
PubMed2003

No evidence for productive PERV infection of baboon cells in in vivo infection model.

OBJECTIVES: The discovery that pig endogenous retroviruses are infectious for human cells in vitro lead to vehement discussions about the possible risk of infection after clinical xenotransplantation. Since PERV transmission to non-human primate cells in vitro has been observed, similar to human cells, infection studies in non-human primates should represent the best model to analyze a potential PERV transmission after xenotransplantation. However, it is still open to discussion, whether non-human primate cells can be infected productively-similar to human cells- and whether those species are suitable to analyze PERV infection risks in vivo. METHODS: In vitro, only few cell types can be tested for susceptibility. We developed a pig to baboon cell transplantation model with special emphasis on B-cell effective immunosuppression, removal of anti Gal-alpha 1,3-Gal-antibodies, inhibition of the complement cascade and long term survival of transplanted cellular grafts. This model allows us to investigate in vivo, whether any baboon cell types may be permissive for productive PERV infection. The xenograft recipients were investigated for up to 535 days post transplantation. Gal-alpha 1,3-Gal-antibody and complement levels were monitored. Potential PERV transmission was analyzed, not only in PBMC, but in a variety of tissue samples as well as in serum and plasma samples by PCR, RT-PCR and by detection of RT-activity. Moreover, potential PERV specific immune responses were studied by a highly sensitive Western-Blot-assay. RESULTS: Despite several days of extremely low levels of Gal-alpha 1,3-Gal-antibody and complement, and despite of long term xenochimerism, no evidence for PERV infection was obtained in any of the tested tissues or in the tested serum samples. CONCLUSION: This study supplies further evidence for a low susceptibility of baboons towards productive PERV infection after xenotransplantation.

Animals↗
PubMedDate not supplied

Behçet's disease patients present high levels of deglycosylated anti-lipoteichoic acid IgG and high IL-8 production after lipoteichoic acid stimulation.

OBJECTIVES: Lipoteichoic acid (LTA), induces some of the clinical symptoms of Behçet's disease (BD) in a rat animal model. These results led to the hypothesis that LTA may also trigger BD in humans. We investigated the humoral and cellular immune response against LTA and lipopolysaccharide (LPS) in patients with BD, and compared these responses with those of patients with active chronic oral ulcers (OU) and normal controls. METHODS: Samples were obtained from 12 active BD, 12 inactive BD, 12 active OU and 12 normal controls. Anti-LTA, anti-LPS antibodies levels and the capacity of immune complexes anti-LTA IgG-LTA to activate complement were studied. Exposed mannose residues in anti-LTA IgG were analyzed in the four groups. The interleukin-8 (IL-8) production by peripheral blood mononuclear cells cultures after LTA and LPS stimulation was also studied in all groups. RESULTS: The capacity to bind mannan binding protein (MBP) of anti-LTA IgGs was significantly higher in BD and active OU patients relative to normal controls (p < 0.001). However, only active BD patients generated significantly higher levels of C5a than controls (p < 0.0001). The IgGs purified from the sera of BD patients showed a high specificity for LTA from Streptococcus sanguis or Streptococcus faecalis. LTA also stimulates the secretion of IL-8 in peripheral blood mononuclear cells isolated from active BD patients. Anti-LPS IgA and IgG titers were significantly higher only in active OU patients relative to normal controls (p < 0.0018). CONCLUSION: These results suggest a mechanism involving LTA from streptococci in the pathogenesis of BD.

Adult↗
PubMed2005

Improvement in the symptoms of smooth muscle dystonia during eculizumab therapy in paroxysmal nocturnal hemoglobinuria.

Aberrant smooth muscle dystonia during hemolytic episodes in paroxysmal nocturnal hemoglobinuria (PNH) is implicated in the symptoms of abdominal pain, dysphagia and erectile dysfunction. Here we report two PNH patients treated with the complement inhibitor, eculizumab. Complement inhibition has been sustained for over 2 years and results in resolution of intravascular hemolysis and amelioration of symptoms associated with smooth muscle contractions.

Abdominal Pain↗