Hyperosmolar conjunctival provocation for the evaluation of nonspecific hyperreactivity in healthy patients and patients with allergy.

Background: Tissue hyperreactivity of target organs to nonspecific stimuli is known to be an important factor in influencing the clinical picture of allergic disease.

Objective: To identify the sensitivity and specificity of a hyperosmolar conjunctival provocation test in predicting conjunctival hyperreactivity and to relate this reactivity to the presence of ocular discomfort in subjects with and without allergy.

Methods: In 50 healthy patients and 19 patients with allergic conjunctivitis during remission phase, symptoms of ocular discomfort triggered by nonspecific stimuli were identified and graded with a discomfort score.

Undetectable phospho-STAT1 in peripheral blood mononuclear cells from patients with chronic hepatitis C who do not respond to interferon-alpha therapy.

Background: Recent studies have suggested that phosphorylated signal transducers and activators of transcription 1 (STAT1) plays an important role in interferon (IFN)-mediated biological functions, including antiviral activity. Moreover, it has been demonstrated that suppressors of the cytokine signal 1 (SOCS1) negatively regulates IFN activities.

Aims: To investigate the involvement of phospho-STAT1 in the response to IFN-alpha therapy in patients with chronic hepatitis C and to evaluate the negative regulatory effect of SOCS1 on STAT1 activation.

Beta-2-glycoprotein I expression on monocytes is increased in anti-phospholipid antibody syndrome and correlates with tissue factor expression.

It is well known that monocytes may play an active role in thrombogenesis, since they may express on their surface tissue factor, the major initiator of the clotting cascade. The results of this investigation demonstrate beta-2-glycoprotein I (beta2-GPI) mRNA expression by human peripheral blood monocytes, indicating that these cells synthesize beta2-GPI. In addition, we show beta2-GPI expression on cell surface of these cells by flow cytometric analysis, and the presence of this protein in cell lysate by Western blot.

Overexpression of lymphocytic GD3 ganglioside and presence of anti-GD3 antibodies in patients with HIV infection.

This study was undertaken to analyze the role of disialoganglioside GD3 in HIV infection and disease progression. We report here the results obtained by both ex vivo and in vitro experiments on (1) surface and cytoplasmic expression and distribution of GD3 in HIV-infected cells, (2) the presence of anti-GD3 antibodies in sera of patients with HIV infection in various stages of the disease, and (3) the association of GD3 expression with HIV-related apoptotic events. GD3 expression was determined by high-performance thin-layer chromatography (HPTLC) and lipid-bound sialic acid and by static and flow cytometric analyses in peripheral blood lymphocytes from 22 AIDS patients, 20 anti-HIV Ab(+) asymptomatic subjects, and 25 healthy donors.

Specificity of anti-phospholipid antibodies in infectious mononucleosis: a role for anti-cofactor protein antibodies.

The antigen specificity of anti-phospholipid antibodies in infectious mononucleosis (IM) was studied using ELISA for the detection of anti-beta2-glycoprotein I (beta2-GPI), anti-annexin V, anti-protein S and anti-prothrombin antibodies and TLC immunostaining for the detection of anti-phospholipid antibodies. This technique enabled us to look at antibodies reacting to 'pure' phospholipid antigens in the absence of protein contamination. Sera from 46 patients with IM, 18 with systemic lupus erythematosus (SLE), 21 with primary anti-phospholipid antibody syndrome (PAPS), 50 with Helicobacter pylori infection and 30 healthy blood donors were tested.

Colocalization and complex formation between prosaposin and monosialoganglioside GM3 in neural cells.

Prosaposin, the precursor of saposins A, B, C, and D, was recently identified as a neurotrophic factor in vitro as well as in vivo. Its neurotrophic activity has been localized to a linear 12-amino acid sequence located in the NH2-terminal portion of the saposin C domain. In this study, we show the colocalization of prosaposin and ganglioside GM3 on NS20Y cell plasma membrane by scanning confocal microscopy.

Overexpression of monosialoganglioside GM3 on lymphocyte plasma membrane in patients with HIV infection.

This study was undertaken to analyze both the GM3 expression on peripheral blood lymphocytes of HIV-infected patients and the relationship between ganglioside content and anti-GM3 reactivity. GM3 expression was determined as a percentage of lipid-bound sialic acid and by cytofluorimetric analysis in 25 AIDS patients, 20 anti-HIV+ asymptomatic subjects, 25 patients with different viral disease, and 25 healthy donors. GM3 distribution was analyzed by immunofluorescence and immunoelectron microscopy.

Characterization of autoantibodies to natural killer cells in HIV-infected patients.

Natural killer (NK) cells in HIV-infected patients have a reduced ability to generate non-MHC restricted cytotoxicity to a variety of target cells. The authors investigated antibodies to NK cells in HIV-infected patients and evaluated effects of these antibodies to NK cell numbers and function. Antibodies to NK cells were determined in 160 HIV-infected patients and 35 healthy controls.

Inhibition of protein S by autoantibodies in patients with acquired protein S deficiency.

This study was undertaken to analyze antibodies to protein S (PS) in patients with an acquired PS deficiency. Plasma from symptomatic patients with acquired (n = 14) or congenital (n = 10) PS deficiency and 10 healthy donors was screened for PS antibodies by immunoblotting and for anti-phospholipid antibodies. PS antibodies (IgG) were detected in five of the patients with acquired PS deficiency.

Prosaposin and prosaptide, a peptide from prosaposin, induce an increase in ganglioside content on NS20Y neuroblastoma cells.

Prosaposin has been recently identified as a neurotrophic factor eliciting differentiation in neuronal cultured cells (NS20Y). In this paper we investigate whether prosaposin and its active peptide (prosaptide) may modify the ganglioside pattern in neuroblastoma cells. The analysis by high performance thin layer chromatography did not reveal qualitative changes in the ganglioside pattern of NS20Y cells incubated in the presence of prosaposin, compared to control cells, but it did reveal an increase of the content of all three major resorcinol positive bands (GM3, GM2, GD1a).

Evidence for the existence of ganglioside molecules in the antigen of Entamoeba histolytica.

Gangliosides were found to be present in Entamoeba histolytica. They were extracted from lyophilized trophozoites of the pathogenic strain HM-1:IMSS and purified by high performance thin-layer chromatography. Two resorcinol-positive bands, comigrating with GM2 and GD1a were demonstrated, revealing the existence of ganglioside molecules in Entamoeba histolytica.

Anticardiolipin and anti-beta 2-GPI are two distinct populations of autoantibodies.

This study has been undertaken to assess whether anticardiolipin and anti-beta 2-GPI are two distinct populations of (auto)antibodies, and to clarify whether the beta 2-GPI region critical for phospholipid binding is also crucial for anti-beta 2-GPI reactivity. Fourteen of the 62 anticardiolipin (aCL) ELISA positive sera (22.6%) were positive for anti-beta 2-GPI by immunoblotting, 42 (67.

Cerebrospinal fluid antiganglioside antibodies in patients with AIDS.

In this study the presence of brain antiganglioside antibodies in the cerebrospinal fluid (CSF) of patients with HIV infection was analysed. CSF samples were collected from 45 patients with AIDS and from 45 anti-HIV negative subjects, 15 of whom presented aseptic meningitis. Nineteen AIDS patients had clinically well-documented encephalopathy.

Detection of antiphospholipid antibodies by immunostaining on thin layer chromatography plates.

There is increasing interest in the role of antiphospholipid antibodies in the so-called 'antiphospholipid antibody syndrome' (APS). The two major methods currently employed for detecting the autoantibodies are the solid phase ELISA and the LAI test (inhibition of phospholipid dependent coagulation assay). In our study we have tested the possibility of detecting antiphospholipid antibodies by immunostaining on thin layer chromatography (TLC) plates, since this technique permits the use of pure phospholipid molecules as antigen.

Autoantibodies against ganglioside GM3 represent a portion of anti-lymphocyte antibodies in AIDS patients.

In this study we analysed the relationship between anti-lymphocytic ganglioside antibodies and anti-lymphocyte antibodies in AIDS patients. Anti-lymphocytic ganglioside antibodies were detected by thin layer chromatography (TLC) immunostaining; three colour flow cytometry was used to analyse circulating antibodies against different lymphocyte subsets. Anti-lymphocytic ganglioside antibodies were detected in 23 out of 49 AIDS patients sera (46.

Role of autoimmunity in protein S deficiency during HIV-1 infection.

The objective of the study was to evaluate the role of autoimmune mechanisms in the pathophysiology of protein S deficiency during HIV-1 infection. In a prospective study the correlation between protein S activity and the presence of anti-protein S autoantibodies or anti-cardiolipin antibodies in HIV-1-positive patients and in a population of patients without HIV infection was investigated. Fifty-five HIV-1-infected patients and 15 hospitalized patients without HIV infection were analysed for protein S activity (functional assay), complement system activation, presence of autoantibodies against protein S (Dot Immunobinding) and levels of anti-cardiolipin IgG antibodies (ELISA).

Protein S and HIV infection. The role of anticardiolipin and anti-protein S antibodies.

It has recently been reported that a large proportion of patients with HIV infection have low free protein S levels. In this study we show that protein S (PS) activity levels, as well as PS antigen (Ag), were significantly lower in 35 HIV-1 infected patients than in the control population (p < 0.001).

GM3 as a target of anti-lymphocytic ganglioside antibodies in AIDS patients.

IgG antibodies reacting with the GM3-comigrating band extracted from pooled AIDS lymphocytes were detected in 33.3% of AIDS patients sera, in 8% of asymptomatic anti-HIV-positive subjects, in none of the sera obtained from asymptomatic anti-HIV-negative drug abusers, from patients with acute B and chronic C hepatitis, and from healthy donors. All positive sera reacted selectively with the GM3-comigrating band obtained from AIDS lymphocytes but not with the corresponding band from normal lymphocytes.

Evidence for the existence of ganglioside molecules on Pneumocystis carinii from human lungs.

This study was undertaken to assess whether glycolipid antigens (particularly gangliosides) are associated with Pneumocystis carinii obtained from human lungs. Gangliosides were extracted, purified in high performance thin-layer chromatography and stained with resorcinol. Two resorcinol-positive bands, co-migrating with GM1 and GD1a were demonstrated, suggesting the existence of ganglioside molecules on P.