Aspects on the alveolar accumulation of T cells in sarcoidosis.
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Bronchoalveolar Lavage Fluid↗
Biomedical subjects
J Hed
Publications and source records attributed to J Hed.
Endocytosis of cigarette-smoke condensate by rabbit alveolar macrophages in vitro measured as fluorescence intensity.
It has previously been shown that alveolar macrophages (AMs) from smokers have increased fluorescence compared to AMs from nonsmokers. In the present investigation, AMs lavaged from rabbits were exposed to a cigarette-smoke condensate (CSC) in order to study its influence on the fluorescence of AMs. Flow cytofluorometry was used. Alveolar cells exposed to 0.01% of CSC showed a fluorescence which increased with higher concentrations of the CSC. Incubation with CSC for 5 min was enough to give a significant rise (p less than 0.001) in cell fluorescence compared to controls. After incubating fluorescent cells with untreated non-fluorescent AMs, fluorescent material was distributed to the non-fluorescent AMs within 30 min. Further more, fluorescence decreased when exposed cells were cultured in CSC-free medium. When incubating CSC with blood leucocytes, an almost threefold increase in fluorescence was observed among the phagocytic cells at 37 degrees C compared to 4 degrees C, whereas the fluorescence in the non-phagocytic cell population only showed a minor enhancement. Endocytosis of fluorescent material in CSC can explain the strong fluorescence seen in AMs from smokers. Exocytosis and re-endocytosis of the material by new AMs may explain the slow decline in the fluorescence of AMs observed after cessation of smoking.
Animals↗
High prevalence of celiac disease in healthy adults revealed by antigliadin antibodies.
Sera from 1866 healthy blood donors and from 40 untreated adults with celiac disease were analyzed using a micro-ELISA assay. Blood donors with IgA antigliadin activity greater than 40 units corresponding to the 96.8th percentile and IgG antigliadin activity greater than 20 units corresponding to the 91.3rd percentile were selected for further investigation and jejunal biopsy. Seven of 49 blood donors with high IgA antigliadin activity showed mucosal lesions typical for celiac disease. None of the donors with high IgG antigliadin activity (35 subjects) but without high IgA activity had such mucosal lesions. A prevalence of celiac disease of at least 1/256 was observed in the donor group. There were significant age-group differences in IgA antigliadin activity. In the present study, a high IgA antigliadin activity had a positive predictive value between 18% and 25% in individuals without symptoms indicative of celiac disease depending on the way the cut-off points were chosen. In contrast, the positive predictive value of high IgG antigliadin activity alone was estimated to be 0%.
Adolescent↗
Quenching of intracellular autofluorescence in alveolar macrophages permits analysis of fluorochrome labelled surface antigens by flow cytofluorometry.
We report a new technique in which the autofluorescence of alveolar macrophages from smokers is quenched by crystal violet. This technique permits immunostaining of surface antigens of these cells and enables the stained cells to be analysed by flow cytofluorometry. The variable solubility of crystal violet makes it important to characterize the crystal violet solution by its quenching properties and not rely on the assumed concentration of dissolved dye. High concentrations of crystal violet lowered the number of cells and gave a decreased amount of surface antigen (CD11b). However, a lower concentration of crystal violet could be used if the cells were fixed with paraformaldehyde (4%) and the membranes were permeabilized with n-octyl-beta-D-glucopyranoside (0.6%). Using a phagocytic model with FITC-conjugated particles we were able to show that this treatment gave an efficient permeabilization of phagolysosomal membranes.
Antigens, Surface↗
A flow cytometric method to measure the stimulated mobilization and the intracellular pool of the adhesion promoting glucoprotein Mac-1.
The receptor for complement factor C3bi (Mac-1 or CR3) belongs to a complex of leukocyte surface glucoproteins (CD11/CD18) that are essential for chemotaxis and adhesion of human polymorphonuclear leukocytes (PMN). Granulocytes can increase their surface expression of Mac-1 upon stimulation and it is proposed that this depends on a rapid mobilization of an intracellular pool of Mac-1. In the present study we describe a cell membrane permeabilization method that enables the detection of the intracellular pool of Mac-1 in granulocytes by flow cytometry. The method is based on the use of the non-ionic detergent n-octyl-beta-D-glucopyranoside (OG) to permeabilize the cell membranes of paraformaldehyde-prefixed leukocytes. It is shown that fMLP (5 x 10(-7) M)-treated cells expose 85% of the total detectable amount of Mac-1 molecules on the surfaces. The method makes it possible to measure the total detectable pool, the efficiency of Mac-1 mobilization and the in vivo expression of the receptor. This could be of value when evaluating the role of adhesion proteins in the inflammatory response.
Adolescent↗
Dust exposure in coeliac disease: a case-referent study.
Case series of coeliac disease show that chronic allergic alveolitis (farmers' lung) and fever reactions due to exposure to organic dust (organic dust toxic syndrome) commonly occur among subjects with coeliac disease and dermatitis herpetiformis, these being related disorders. In this case-referent study 105 cases of coeliac disease and dermatitis herpetiformis were compared with 237 referents from the general population by means of a mail inquiry regarding exposure to various environmental factors. Increased odds ratios were obtained with exposure to various farm animals and more clearly for cotton dust, although numbers were few. Animal husbandry in Sweden invariably means heavy exposure to organic dust. The fact that comparatively few persons reported dust exposure may be of doubtful validity in view of the high frequency of exposure to farm animals reported by the cases.
Adult↗
Antibody responses to hepatitis C virus and its modes of transmission in dialysis patients.
Five of 72 patients dialysed at the same dialysis unit developed elevated alanine aminotranspherase (ALT) levels attributed to acute non-A, non-B hepatitis (NANBH). Histopathologic findings consistent with NANBH were present in four of them. Serological screening for antibodies to hepatitis C virus (anti-HCV) was performed in all 72 cases. Three of the patients with NANBH and 2 of the other 67 patients had positive tests. Low and transient levels of anti-HCV were noted in 2 patients with NANBH in spite of chronic hepatitis. Only 1 of 5 patients with NANBH was known to have had blood transfusions indicating other, as yet undefined, modes of transmission of HCV for the others. Although antibody responses to HCV might be transient or low, testing for anti-HCV should be considered in dialysis populations.
Alanine Transaminase↗
Raised IgG and IgM in "epidemic" IDDM suggest that infections are responsible for the seasonality of type I diabetes.
Serum levels of immunoglobulins G, A and M were quantitatively measured at diagnosis and at regular intervals for four years in 92 type I (insulin-dependent) diabetes patients. The patients were 0.8-15.99 years of age at diagnosis. Thirty-six of them got diabetes during periods of high incidence (the "epidemic" group) and 56 of them were diagnosed during periods of seemingly low incidence (the non-"epidemic" patients). Fifty percent (18/36) of the "epidemic" group had infections less than two months preceding diagnosis as compared to 29% (16/56) (p less than 0.01) of the non-"epidemic" patients. At diagnosis immunoglobulins G, and M in the "epidemic" group were 11.28 +/- 2.0 and 1.97 +/- 0.77 as compared to 9.9 +/- 2.3 (p less than 0.01) and 1.31 +/- 0.58 (p less than 0.001) respectively in the non-"epidemic" patients. The same highly significant differences were observed when mean values of IgG and IgM were compared between children who had infections less than two months before diagnosis and those without preceding infections. Except for slightly higher (p less than 0.12) total (OKT3) T-lymphocytes and higher (p less than 0.03) B-lymphocytes at diagnosis in the "epidemic" group, there were no significant differences in quantitative T- and B-lymphocyte subpopulations between various groups. 6.3% (2/32) of the patients who had preceding infections had HLA-DR3/non-DR4 genotypes as compared to 30.6% (15/49); p less than 0.001, of those patients without preceding infections.(ABSTRACT TRUNCATED AT 250 WORDS)
Adolescent↗
The inhibition of CR1 mobilization of human granulocytes by the presence of erythrocytes. A possible mechanism for intravascular regulation of granulocyte modulation.
In this study we show a spontaneous mobilization at 37 degrees of the complement receptor for C3b (CR1) of granulocytes prepared by a method in which erythrocytes were removed by specific lysis, as well as a method where granulocytes were prepared by dextran sedimentation at low temperature without using centrifugation. This increase of CR1-expression was not obtained when erythrocytes were present during the incubation. This inhibitory effect of erythrocytes was maximal at an erythrocyte:granulocyte ratio of 600:1 or more and was not caused by interference with the fluorescence of the immunoassay. EDTA plasma had no inhibitory effect on CR1 mobilization, indicating that the phenomenon was not due to plasma proteins, nor the used anti-coagulant. An increased CR1 mobilization was, however, obtained in the presence of erythrocytes if the granulocytes were simultaneously exposed to the chemotactic stimulus formyl-methionyl-leucyl-phenylalanine (FMLP) at the concentration 10(-9) M or more. However, to obtain a CR1 expression comparable to systems without erythrocytes, a 10-fold higher concentration of FMLP was needed. These results suggest that the inhibitory effect of erythrocytes on the spontaneous receptor mobilization of granulocytes could be a mechanism to keep the complement receptors and other surface structures within the cells while circulating in the blood, to be expressed at the cellular surface only by the appropriate signal, such as propagated by soluble mediators from an inflammatory focus.
Adolescent↗
Celiac disease and organic dust toxic syndrome.
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Adult↗
The effect of maternal avoidance of eggs, cow's milk, and fish during lactation on the development of IgE, IgG, and IgA antibodies in infants.
Serum levels of IgE, IgE antibodies to egg white (EW) and cow's milk (CM), IgG, and IgA antibodies to ovalbumin (OA) and beta-lactoglobulin (BLG) were measured in a group of 115 infants with a family history of atopy/allergy at birth and at 3, 6, 9, 12, and 18 months of age. The mothers of 65 infants avoided eggs, CM, and fish during the first 3 months of lactation (maternal antigen avoidance diet, D group), whereas the remaining 50 mothers had no diet restrictions (no maternal antigen avoidance diet, ND group). CM was introduced after 6 months of age and EW after 9 months. The only statistically significant difference between the D and ND group infants was a lower rate of specimens with IgE antibodies to EW and/or CM in the infants at 3 months of age (p = 0.008). IgE antibodies to EW and/or CM appeared in 62 infants during the study period and often during complete breast-feeding. In 40 of the infants, IgE antibodies appeared before the introduction of EW and CM into the diet. The IgE concentrations of the D and the ND group infants were similar. Cord-blood IgE was a poor predictor of atopy/allergy; for example, only seven of 103 infants with double heredity for atopy/allergy had values above the 90th percentile of our normal reference. The concentrations of IgG antibodies to OA and BLG were similar in the two groups. The levels decreased significantly (p less than 0.001) from birth to 6 months of age, indicating a passive placental transfer.(ABSTRACT TRUNCATED AT 250 WORDS)
Adult↗
Different cell surface and phagocytic properties in mononuclear phagocytes from blood and alveoli. A comparative study of blood monocytes and alveolar macrophages from human nonsmokers using flow cytofluorometry.
Flow cytofluorometry was used to compare blood monocytes (BMs) and alveolar macrophages (AMs) from the same nonsmoking subject (n = 13). Autofluorescence was quantified, cell surface markers (HLA-DR, CR3) were detected by monoclonal antibodies, and phagocytic ability was determined using C3b-coated yeast particles. AMs expressed more HLA-DR (p less than 0.001) and CR3 (p less than 0.01) on their surfaces than did BMs. The phagocytic capacity was enhanced in AMs compared to BMs (p less than 0.001) and the cells showed an increased autofluorescence (p less than 0.001) in the alveoli compared to blood. The findings suggest that the mononuclear phagocyte is activated when it migrates from blood to alveoli in order to adapt to the milieu in the alveolar space.
Adult↗
Presence of IgA and IgG antigliadin antibodies in healthy adults as measured by micro-ELISA. Effect of various cutoff levels on specificity and sensitivity when diagnosing coeliac disease.
In this study a micro-ELISA (ELISA = enzyme-linked immunosorbent assay) was established and used to evaluate IgA and IgG antigliadin antibodies in 1,866 healthy adults. There was a covariation between the level of IgA antigliadin antibodies and the total serum IgA concentration, probably due to an increased IgA response in some healthy subjects. We could not find any correlation between the presence of IgG and IgA antibodies in the healthy population using the 97.5th percentile as a cutoff value. The specificity of various cutoff levels was compared with the sensitivity of the test in a population of 40 patients with coeliac disease. IgA antigliadin antibodies had a high specificity (95%) at a cutoff value giving a high sensitivity (80%). This was not possible with IgG antigliadin antibodies which had a low sensitivity (40%) when the cutoff value was selected to give a high specificity. Due to the low prevalence of coeliac disease, a decrease in the specificity of the test will have a pronounced effect on the positive predictive value. The results indicate that only IgA antigliadin antibodies are useful markers when screening subjects with few typical symptoms for biopsy when diagnosing coeliac disease, whereas IgG antibodies are of low value because of their low specificity.
Adolescent↗
Alveolar macrophages from smokers show strong intracellular fluorescence.
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Fluorescence↗
A new membrane permeabilization method for the detection of intracellular antigens by flow cytometry.
This article describes a new cell membrane permeabilization method for the detection of intracellular antigens by immunofluorescence staining and flow cytometry. The number of cells remained unaltered and no cell aggregation or loss of intracellular antigenicity was observed after this permeabilization treatment. A mixed leukocyte population from human peripheral blood was used in this study and the leukocytes were fixed and permeabilized, which permitted monoclonal anti-vimentin antibodies to reach intracellular antigens. The stabilization of cell membranes and preservation of intracellular antigenicity was achieved with paraformaldehyde fixation. This pretreatment prevents cell destruction and subsequent treatment with the detergent n-octyl-beta-D-glucopyranoside results in permeabilization of the cell membrane. The procedure does not alter the expression of cell surface antigens, which is of importance if phenotypic characterization of intracellularly stained cells is to be undertaken. Furthermore, this simple, rapid and reproducible technique makes it possible to detect and distinguish between different human peripheral blood leukocytes without prior purification steps. The leukocyte subpopulations remain well-separated and easily detectable by flow cytometry.
Antibodies, Monoclonal↗
[Diagnosis of antibodies against leukocyte antigens].
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Antibodies↗
Improved cell depletion in a panning technique using covalent binding of immunoglobulins to surface modified polystyrene dishes.
A method for the chemical modification of plastic surfaces permits covalent binding of proteins and we have used this method in the development of an efficient panning technique. Thus, human peripheral T lymphocytes coated with mouse monoclonal antibodies directed against the CD4 marker may be selectively and reproducibly removed from a lymphocyte population by a short incubation in modified plastic dishes coated with rabbit anti-mouse IgG antibody. Due to the higher protein binding capacity of the dishes the use of the IgG fraction of the coating antibody was sufficient for optimal and reproducible results. In contrast, control dishes with passively adsorbed antibody required an affinity-purified fraction and even then were less efficient.
CD4-Positive T-Lymphocytes↗
Erythrocyte-mediated scavenging of reactive oxygen metabolites generated by human polymorphonuclear leukocytes during phagocytosis: comparison between normal and Down's syndrome blood cells.
The phagocytosis of complement-opsonized yeast particles by polymorphonuclear leukocytes from normal and Down's syndrome subjects was compared in the absence and presence of erythrocytes. Granulocytes from children with Down's syndrome showed a large increase of metabolic activity, as measured with chemiluminescence. This was not associated with autooxidative damage in the presence of erythrocytes. The results indicate that erythrocytes could exert an antioxidant effect on the granulocyte cell surface. This was reflected in an enhanced ingestion, which was more pronounced in the presence of Down erythrocytes with a higher superoxide dismutase and glutathione peroxidase content, than normal cells. Our conclusion is that the increase of reactive oxygen metabolites scavengers in Down's syndrome blood cells is of benefit for the homeostasis between generated reactive oxygen metabolites and their propagation.
Adolescent↗