Granulocyte Membranes Research Articles

Chemical characteristics of peripheral blood granulocyte biomembranes in frequently ill children with autonomic dysfunction syndrome

The problem of frequently ill children has extreme relevance in medical practice. A special group is FIC with autonomic dysfunction syndrome, born prematurely with perinatal damage of the central nervous system (CNS). In previous studies, we found that FIC who were born prematurely with perinatal damage of the central nervous system exhibit lower immunoreactivity than their healthy peers. Purpose of the work – to study the biochemical indicator of immunocompetent cells (the study of the phospholipid composition of granulocyte membranes) of the frequently ill children with autonomic dysfunction syndrome, born prematurely with perinatal damage to the central nervous system (CNS). Materials and methods. 68 children in the age of 6-7 years who are belonging to the group of frequently ill were examined. Out of 68 children, there were 36 children with autonomic dysfunction syndrome (SVD) born prematurely with perinatal hypoxic-ischemic damage to the central nervous system (group 1) and 32 children without autonomic dysfunction syndrome born on time without central nervous system damage (group 2). Results. A study of the phospholipid composition of blood granulocyte membranes of patients of the studied groups revealed significant differences comparison with the control group. The revealed changes in granulocyte biomembranes were more pronounced for FIC with SVD born prematurely with perinatal CNS damage than for children born on time without CNS and SVD damage. Conclusions. The obtained data allow us to conclude that FIL who were born preterm with perinatal damage of the central nervous system, changes in the biochemical characteristics of membranes are observed to a slightly greater extent than for children who were born on time without central nervous system damage. The revealed changes in immunocompetent cells are characterized by an increase in the polarity of the lipid component of biomembranes and a decrease in the relative content of neutral lipids in them. These violations lead to a change in protein-lipid interactions, which, as a result, leads to a change in the microviscosity of biomembranes and their structural and functional properties. At these children forme an inferior immune response to an infectious agent.

Randomized clinical trial of perioperative omega-3 fatty acid supplements in elective colorectal cancer surgery

Omega-3 fatty acids (n-3 FAs) may have beneficial clinical effects, and n-3 FA supplements may improve outcome after surgery. In a randomized double-blind placebo-controlled trial in single centre, patients referred for elective colorectal cancer surgery received either an n-3 FA-enriched oral nutritional supplement (ONS) (Supportan, 200 ml twice daily) providing 2.0 g eicosapentaenoic acid (EPA) and 1.0 g docosahexaenoic acid (DHA) per day, or a standard isocaloric and isonitrogenous ONS, for 7 days before and 7 days after surgery. The primary endpoint was infectious and non-infectious complications within 30 days of surgery. Secondary endpoints were length of hospital stay, intensive care unit admission, readmissions, and concentrations of marine n-3 FAs and arachidonic acid in granulocyte membranes. Some 148 consecutive patients (68 women, 80 men; mean age 71 (range 41-89) years) were randomized. There was no significant difference between groups in infectious or non-infectious postoperative complications (P = 1.000). Granulocyte levels of EPA, DHA and docosapentaenoic acid (DPA) were significantly higher in the n-3 FA-enriched supplement group compared with the control group (P < 0.001). The arachidonic acid level in granulocytes was significantly lower in the enriched group than in the control group (P < 0.001). EPA, DHA and DPA were incorporated into granulocytes in patients receiving n-3 FAs, but this was not associated with improved postoperative outcomes. NCT00488904 (http://www.clinicaltrials.gov).

Functional characterization of a synthetic abscisic acid analog with anti-inflammatory activity on human granulocytes and monocytes

The phytohormone abscisic acid (ABA), in addition to regulating several important physiological functions in plants, is also produced and released by human granulocytes and monocytes where it stimulates cell activities involved in the innate immune response. Here we describe the properties of an ABA synthetic analog that competes with the hormone for binding to human granulocyte membranes and to purified recombinant LANCL2 (the human ABA receptor) and inhibits several ABA-triggered inflammatory functions of granulocytes and monocytes in vitro: chemotaxis, phagocytosis, reactive oxygen species production and release of prostaglandin E 2 (PGE 2) by human granulocytes, release of PGE 2 and of monocyte chemoattractant protein-1 by human monocytes. This observation provides a proof of principle that ABA antagonists may represent a new class of anti-inflammatory agents.

The Effect of n-3 Fatty Acids on C-Reactive Protein Levels in Patients With Chronic Renal Failure

Cardiovascular disease (CVD) is the leading cause of mortality in patients with chronic renal failure (CRF). C-reactive protein (CRP), a strong independent risk marker of CVD, is elevated in a large proportion of patients with CRF. The long-chain n-3 polyunsaturated fatty acids (PUFA) have cardioprotective effects, which may be partly attributed to their anti-inflammatory properties. The study objective was to investigate the effect of n-3 PUFA on serum levels of CRP in patients with CRF. We performed a randomized, double-blind, placebo-controlled study. The study took place at an outpatients clinic at the Department of Nephrology, Aalborg Hospital, Denmark. The study comprised 46 patients (30 men and 16 women; mean age 59 +/- 11 years) with a serum creatinine level in the range of 150 to 400 micromol/L. The patients were randomly assigned to daily supplementation with 2.4 g n-3 PUFA or identical capsules containing 2.4 g of olive oil (control) for 8 weeks. CRP was measured with a high-sensitivity C-reactive protein (hs-CRP) assay and the content of n-3 PUFA in granulocyte membranes before and after supplementation. The n-3 PUFA concentration increased in granulocytes after the n-3 PUFA supplements but was unaltered by the control oil. A nonsignificant reduction in hs-CRP was observed in the n-3 PUFA group after supplementation (2.46 vs. 1.47 mg/L; P = .06), and hs-CRP was unaltered by the control oil (3.27 vs. 3.14 mg/L; P = .12). There was no difference in median hs-CRP change in the two groups. A trend was seen toward a reduction in hs-CRP in the n-3 PUFA group, but there was no significant difference in hs-CRP levels when both groups were compared.

Soluble adhesion molecules and marine n-3 fatty acids in patients referred for coronary angiography

Objective: To investigate the relationship between soluble cellular adhesion molecules (sCAMs) and the extent of coronary artery disease (CAD) in patients with stable angina pectoris. Methods and results: Two hundred and ninety-one subjects had fasting levels of circulating intercellular adhesion molecule-1(sICAM-1), vascular cellular adhesion molecule-1 (sVCAM-1), sP-selectin and contents of n-3 polyunsaturated fatty acids (n-3 PUFA) in granulocyte membranes and adipose tissue determined before undergoing elective coronary angiography. Levels of soluble VCAM-1 (983 ± 216 versus 893 ± 196 ng/l, p < 0.001), ICAM-1 (318 ± 140 versus 290 ± 75 ng/l, p < 0.05) and P-selectin (90 ± 27 versus 80 ± 23 ng/l, p < 0.01) were significantly increased in subjects with significant CAD compared to subjects with no significant stenoses. In a linear regression analysis, both sVCAM-1 and sP-selectin, but not sICAM-1, correlated to the presence and the severity of CAD. Both sICAM-1 and sP-selectin were significantly correlated to current smoking status and a history of myocardial infarction. The content of total n-3 PUFA and docosahexaenoic acid in adipose tissue was marginally, but significant positively correlated to VCAM-1. Conclusion: sVCAM-1 and sP-selectin may serve as markers of CAD in patients with stable angina pectoris. Only sVCAM-1 was weakly correlated to n-3 PUFA in adipose tissue.

Soluble adhesion molecules in healthy subjects: a dose-response study using n-3 fatty acids

Long-chain n-3 polyunsaturated fatty acids (PUFA) may protect against atherosclerotic disease, and serum levels of soluble cellular adhesion molecules (sCAMs) possibly reflect the inflammatory process underlying atherosclerosis. We studied the effect of n-3 PUFA dietary supplementation on the serum levels of sP-selectin, soluble intercellular adhesion molecule-1 (sICAM-1) and soluble vascular adhesion molecule-1 (sVCAM-1), and the correlation between sCAMs and the fatty acid composition of granulocyte membranes. Sixty healthy volunteers were randomly assigned to receive a daily supplement of n-3 PUFA 6.6 g, n-3 PUFA 2.0 g, or olive oil for 12 weeks in a double blind design. A significant negative correlation was found between serum sICAM-1 levels and the DHA content of granulocyte membranes at entry. After supplementation with 6.6 g of n-3 PUFA, there was a significant decrease only in sP-selectin, which a gender subanalysis showed to be more marked in men. Among the women, there was a significant decrease in sICAM-1 in the PUFA 2.0 g group and a significant increase in sVCAM-1 in the PUFA 6.6 g group. The results indicate that high-dose supplementation with n-3 PUFA decreases sP-selectin levels in healthy subjects, thus suggesting a decrease in platelet reactivity or endothelial activation. However, the effect of n-3 PUFA on sCAMs is complex and may depend on gender and n-3 PUFA dose.

C-reactive protein, dietary n-3 fatty acids, and the extent of coronary artery disease

The acute-phase reactant C-reactive protein (CRP) has emerged as an independent risk factor for coronary artery disease. Experimental and clinical studies provide evidence of anti-inflammatory effects of n-3 polyunsaturated fatty acids (PUFA) derived from fish. We have studied the effect of marine n-3 PUFA on CRP levels in 269 patients referred for coronary angiography because of clinical suspicion of coronary artery disease. All patients filled out a food questionnaire regarding fish intake. The n-3 PUFA content of granulocyte membranes was determined and the concentration of CRP in serum was measured using a highly sensitive assay. The results were related to angiographic findings. CRP was significantly higher in patients with significant coronary stenoses than in those with no significant angiographic changes (p <0.001), but the CRP levels were not associated with the number of diseased vessels. Subjects with CRP levels in the lower quartile had a significantly higher content of docosahexaenoic acid (DHA) in granulocytes than subjects with CRP levels in the upper quartile (p = 0.02), and in a multivariate linear regression analysis, DHA was independently correlated to CRP (R 2 = 0.179; p = 0.003). The inverse correlation between CRP and DHA may reflect an anti-inflammatory effect of DHA in patients with stable coronary artery disease and suggest a novel mechanism by which fish consumption may decrease the risk of coronary artery disease.

Marine n-3 fatty acids, wine intake, and heart rate variability in patients referred for coronary angiography.

Dietary n-3 polyunsaturated fatty acids (PUFAs) derived from fish may reduce the incidence of sudden cardiac death (SCD). In addition, wine drinking is suggested to have a protective effect against cardiovascular death. We included 291 patients referred for coronary angiography in whom ischemic heart disease was suspected and all of whom completed a food questionnaire regarding fish and wine intake. The n-3 PUFA composition of granulocyte membranes and of adipose tissue was measured. In addition, 24-hour heart rate variability (HRV) was analyzed. Fish intake was positively associated with the level of n-3 PUFAs in adipose tissue. Significant positive correlation coefficients were found between HRV indices and the levels of n-3 PUFAs in granulocytes. Wine intake was also significantly positively related to HRV, but the patients with the highest wine intake also had the highest intake of fish, as documented by a high n-3 PUFA content in adipose tissue. Multiple linear regression analysis revealed that traditional factors such as treatment with ss-blockers, smoking, age, and previous myocardial infarction were independently related to HRV, and furthermore that n-3 PUFAs (but not wine intake) were significantly independently associated with HRV. The close positive association between n-3 PUFAs and HRV in patients suspected of having ischemic heart disease may indicate a protective effect of n-3 PUFAs against SCD. This may partly explain the reduction in SCD observed in humans with a modest intake of n-3 PUFA. Wine intake was also positively correlated with HRV, but this correlation was no longer significant after controlling for the cellular level of n-3 PUFA.

Tobacco smoking induces expression of very-high-affinity nicotine binding sites on blood polymorphonuclear cells.

The targets of nicotine in the central nervous system (CNS) have been identified as nicotinic acetylcholine (ACh) receptors. Because of their localization in the brain, no data are available about their in vivo modifications. However, nonneuronal nicotine binding sites have been identified on peripheral blood cells. The present study was designed to evaluate the effects of tobacco smoking on granulocyte nicotine binding sites. Binding assays were performed on granulocyte membranes using (-)(3H)nicotine and were analyzed by the Scatchard method in nonsmokers (n=10), smokers (n=10), and ex-smokers (n=10). In nonsmokers, a single-affinity binding site was detected with Kd = 1.08 +/- 0.05 x 10 -9 M. In contrast, in smokers, two different classes of binding sites were identified: one with Kd1 = 2.80 +/- 0.81 x 10 -11 M and another with Kd2 = 3.92 +/- 0.58 x 10 -9 M, similar to the binding site in nonsmokers. Moreover, a twofold increase in nicotine binding-site density was observed in smokers. Ex-smokers recovered a single class of binding sites similar to those observed in nonsmokers when they had stopped smoking for more than 1 yr, whereas recent ex-smokers (1 to 8 mo) displayed a pattern similar to that in smokers, as demonstrated by the persistence of two classes of nicotine binding sites. Chronic nicotine exposure induces modifications of nicotine binding sites on granulocytes. It is noteworthy that the persistence of such alterations corresponds to the very high rate of relapse into smoking observed during the early stages of tobacco cessation. Consequently, monitoring of nicotine binding sites could constitute an interesting approach to understanding the pharmacologic mechanisms involved in tobacco dependence.

Hormone replacement therapy affects various immune cell subsets and natural cytotoxicity.

The effects of hormone replacement therapy (HRT) on lymphocytes and granulocytes have never been determined in detail. Ten healthy menopausal women (age 49-51 years; menopause less than 2 years) were treated for 6 months by administering transdermal estradiol (100 micrograms/day for 21 consecutive days) and oral medroxyprogesterone acetate (10 mg/day from day 10 to day 21). Days 22-28 were therapy-free. All subjects were examined during the first and the last month of treatment: evaluations were carried out on days 0, 8, 21 and 28. CD4+CD45RO+ cells were found to be significantly reduced on day 8. CD56+ cells and CD8+CD11b+ cells were decreased on day 21 and recovered basal level on day 28. Natural killer cell function was transiently increased on day 8 and greatly reduced on day 21. During the first month of therapy, the expression of Leu8 and CD11b antigens on granulocyte membranes was significantly affected by HRT. Taken together, the results indicate that HRT selectively affects various immune cell subsets.

S-Prenylated Cysteine Analogs Inhibit Receptor-Mediated G Protein Activation in Native Human Granulocyte and Reconstituted Bovine Retinal Rod Outer Segment Membranes

We have previously shown that the S-prenylated cysteine analogue N-acetyl-S-trans,trans-farnesyl-L-cysteine (L-AFC) inhibits basal and formyl peptide receptor-stimulated binding of guanosine 5'-O-(3-thiotriphosphate) (GTP[S]) to and hydrolysis of GTP by membranes of HL-60 granulocytes and have presented evidence suggesting that this inhibition was not caused by reduced protein carboxyl methylation [Scheer, A., & Gierschik, P. (1993) FEBS Lett. 319, 110-114]. We now report a detailed analysis of the structural properties of S-prenylated cysteine analogues required for this inhibition and demonstrate that S-prenylcysteines also suppress basal and receptor-stimulated GTP[S] binding to human peripheral neutrophil and HL-60 granulocyte membranes when stimulated by formyl peptide and complement C5a, respectively. S-Prenylcysteines did not affect pertussis toxin-mediated [32P]ADP-ribosylation of Gi proteins. The inhibitory effect of L-AFC was reversible and was not mimicked by farnesylic acid. L-AFC also interfered with GTP[S] binding to retinal transducin when stimulated by light-activated rhodopsin in a reconstituted system. This inhibitory effect was fully reversed upon increasing the concentration of either the G protein beta gamma dimer or the activated receptor. On the basis of these results, we suggest that S-prenylated cysteine analogues like L-AFC inhibit receptor-mediated G protein activation by specifically and reversibly interfering with the interaction of activated receptors with G proteins, most likely with their beta gamma dimers, rather than by inhibiting alpha.beta gamma heterotrimer formation.

P-glycoprotein expression and function in circulating blood cells from normal volunteers

In contrast to its clearly defined role as a multidrug efflux pump in neoplastic cells, the physiologic function of P-glycoprotein (P-gly) in normal cells is unclear. Recent reports identifying P-gly in normal blood and bone marrow suggest that hematopoietic development or function may be dependent on P-gly. To understand the normal function of P-gly in the blood, its level of expression and function must first be quantitated relative to a known standard. In this study, P-gly, MDR1 gene expression, and P-gly function were quantitated in normal leukocytes. P-gly and MDR1 expression were analyzed in individual leukocyte lineages (T-helper, T-suppressor, monocyte, granulocyte, B- lymphocyte, NK cell) from normal volunteers. P-gly on the cell surface was detected by fluorescent double-labeling for lineage (CD4, CD8, CD14, CD15, CD19, CD56, respectively) and P-gly (MRK16) with analysis by flow cytometry and in some cases immunoblot analysis. MDR1 mRNA analysis on purified lineages was performed using quantitative reverse transcription-polymerase chain reaction. P-gly function was determined for each lineage using dual-labeling for lineage and P-gly substrate (rhodamine 123). The P-gly expressing human myeloma cell line, 8226/Dox6, was used as a reference of comparison for levels of P-gly, MDR1 mRNA, and function. CD56+ cells expressed the highest levels of MDR1 mRNA followed by CD8+ &gt; CD4+ approximately equal to CD15+ &gt; CD19+ &gt; CD14+, with percentage values relative to Dox6 of 49%, 17%, 8%, 8%, 4%, and 2%, respectively. The assays for P-gly immunofluorescence and function correlated well with mRNA analysis except for CD15+ cells (granulocytes), which showed a moderate MDR1 mRNA level with a lack of both function and surface P-gly staining. Granulocyte membranes did show P-gly on immunoblot analysis when probed with either C219 or JSB1. We conclude that (1) P-gly and the MDR1 mRNA are expressed in normal leukocytes, (2) this P-gly expression is lineage specific with relatively high levels among CD56+ cells, and (3) the expression of P- gly in granulocytes is not associated with transport of the P-gly substrate, rhodamine 123, out of the cell.

P-Glycoprotein Expression and Function in Circulating Blood Cells From Normal Volunteers

AbstractIn contrast to its clearly defined role as a multidrug efflux pump in neoplastic cells, the physiologic function of P-glycoprotein (P-gly) in normal cells is unclear. Recent reports identifying P-gly in normal blood and bone marrow suggest that hematopoietic development or function may be dependent on P-gly. To understand the normal function of P-gly in the blood, its level of expression and function must first be quantitated relative to a known standard. In this study, P-gly, MDR1 gene expression, and P-gly function were quantrtated in normal leukocytes. P-gly and MDR1 expression were analyzed in individual leukocyte lineages (T-helper, T-suppressor, monocyte, granulocyte, B-lymphocyte, NK cell) from normal volunteers. P-gly on the cell surface was detected by fluorescent double-labeling for lineage (CD4, CD8, CD14, CD15, CD19, CD56, respectively) and P-gly (MRK16) with analysis by flow cytometry and in some cases immunoblot analysis. MOR1 mRNA analysis on purified lineages was performed using quantitative reverse transcription-polymerase chain reaction. P-gly function was determined for each lineage using dual-labeling for lineage and P-gly substrate (rhodamine 123). The P-gly expressing human myeloma cell line, 8226/Dox6, was used as a reference of comparison for levels of P-gly, MDR1 mRNA, and function. CD56+ cells expressed the highest levels of MDR1 mRNA followed by CD8+ > CD4+ ≅ CD15+ > CD19+ > CD14+, with percentage values relative to Dox6 of 49%, 17%, 8%, 8%, 4%, and 2%, respectively. The assays for P-gly immunofluorescence and function correlated well with mRNA analysis except for CD15+ cells (granulocytes), which showed a moderate MDR1 mRNA level with a lack of both function and surface P-gly staining. Granulocyte membranes did show P-gly on immunoblot analysis when probed with either C219 or JSB1. We conclude that (1) P-gly and the MDR1 mRNA are expressed in normal leukocytes, (2) this P-gly expression is lineage specific with relatively high levels among CD56+ cells, and (3) the expression of P-gly in granulocytes is not associated with transport of the P-gly substrate, rhodamine 123, out of the cell.

Two proteins associated with secretory granule membranes identified in chicken regulated secretory cells

Lately, we have identified two polypeptides of 92-94 kDa (GRL1) and 45-60 kDa (GRL2), expressed in cytoplasmic granules of chicken granulocytes and thrombocytes. Here, we report that GRL1 and GRL2 are widely distributed in all exocrine and several endocrine cell types, but not in neurons of the central nervous system, during late stages of embryonic development, as well as in newly hatched and two-month-old chickens. Immunogold studies in ultrathin frozen sections of pancreatic acinar cells show that GRL1 and GRL2 are co-localized at the periphery of zymogen granules, in granules fused with apical acinar membranes and on apical membranes of acini, while the pregranular compartments of the secretory pathway are weakly or not labeled. Semiquantitative morphometric studies indicate that GRL1 and GRL2 are equally distributed in secretory granules. A variety of physical and metabolic studies reveal that GRL2, a highly N-glycosylated polypeptide, is an intrinsic membrane protein, while GRL1 is a peripheral membrane polypeptide released by Na2CO3 treatment of granulocyte membranes. In all hematopoietic, exocrine or endocrine cells examinated, GRL1 shows identical electrophoretic patterns, while GRL2 is identified as a diffuse band, at 40-65 kDa, in hematopoietic and pancreatic cells. Taken together, the morphological and biochemical studies indicate that GRL1 and GRL2 are components of the secretory granule membrane in chicken exocrine, endocrine and hemopoietic cell types.

Monoclonal, anti-domain and anti-peptide antibodies assign the molecular weight 160,000 granulocyte membrane antigen of the CD66 cluster to a mRNA species encoded by the biliary glycoprotein gene, a member of the carcinoembryonic antigen gene family.

mAb directed against the CD66 cluster of granulocyte differentiation Ag recognize Ag of the carcinoembryonic Ag family. A major Ag in extracts from granulocyte membranes bound by CD66 antibodies exhibits a relative molecular mass of 160,000. According to recent data, this Ag may be a product of the biliary glycoprotein (BGP) gene that belongs to the CEA gene family. As a result of alternative splicing, the BGP gene is transcribed into at least seven distinct mRNA species. To identify splice variants of BGP, antisera were raised against the A2 domain expressed in bacteria and to a peptide comprising the C-terminal 23 amino acids encoded by the 3' exon of the BGP gene. The antisera and an mAb specific for members of the BGP family were used to identify potential BGP splice variants in granulocyte membranes. For comparison, the binding of antibodies to Ag purified from human bile was investigated. In the membrane preparation from granulocytes, the only Ag identified by the mAb, the domain antiserum and the peptide antiserum, was the Ag of M(r) 160,000 recognized by a CD66 antibody. These results indicate that the M(r) 160,000 granulocyte membrane Ag of the CD66 cluster is the product of the BGP-specific mRNA containing all coding sequences of the BGP gene. Among two major biliary glycoproteins present in human bile, the M(r) 115,000 Ag contains the A2 domain, whereas the domain is lacking in the "classical" biliary glycoprotein of M(r) 85,000. None of the bile Ag bound the peptide antiserum.

Rapid Degradation of NAD by Retinoic Acid-Differentiated HL-60 Granulocyte Membranes Prevents ADP Ribosylation

Pertussis and cholera toxins failed to ADP-ribosylate Gα s and Gα i in membranes isolated from retinoic acid-differentiated HL-60 granulocytes, although Gα i subunits were present. NAD was rapidly degraded in the presence of these membranes, primarily to ADP-ribose, to less than 10% of initial activity by 5 min. Metabolism of NAD was heat labile and inhibited by NADP, but not by imidazole or isonicotinic acid hydrazine. Pertussis toxin uncoupled LTB 4 receptors from G proteins in intact retinoic acid-differentiated HL-60 cells. Retinoic acid differentiation stimulates expression of a unique NAD-glycohydrolase activity in HL-60 granulocytes which prevents ADP-ribosylation in isolated membranes, but not intact cells.

Identification of membrane antigens in granulocytes and colonic carcinoma cells by a monoclonal antibody specific for biliary glycoprotein, a member of the carcinoembryonic antigen family

The gene coding for ‘biliary glycoprotein (BGP)’ is a member of the carcinoembryonic antigen (CEA) gene family. A monoclonal antibody (MAb) was induced against a BGP-preparation isolated from human bile. The antibody did not crossreact with the carcinoembryonic antigen (CEA) and different non-specific crossreacting antigens. The anti-BGP MAb was used to identify BGP-related antigens in membrane extracts from granulocytes and the colonic carcinoma cell line HT-29. In granulocyte membranes, a single antigen of M r 160 000 was bound. In membranes from HT-29 cells, a main antigen of M r 85 000 was present. At high antigen concentration, an additional antigen of M r 115 000 was identified. Since several transcripts of the BGP gene have been identified, the different BGP related antigens are probably products of alternatively spliced mRNAs.

In vivo andin vitro HeNe laser effects on phagocyte functions

The goal of this work was to evaluate the effect of helium-neon (HeNe) laser irradiation on immunocompetent cells. We used the in vivo skin window method and in vitro granulocyte function tests. The study of cellular migration showed a marked decrease in vitro and in vivo in a dose-independent manner. Superoxide release was not modified by laser irradiation. The granulocyte's aggregation, when using PHA and PMA, presented a reduction that was statistically very significant, not as a subordinate dose. An increase of the release of ATP was demonstrated only at 4 joules and precedes granulocyte aggregation. When using Ca2+ ionophore A23187 as stimulus, laser irradiation at 1, 2 or 4J did not show any modification of granulocyte aggregation. The monoclonal antibody 60.1, which identifies a membrane antigen fundamental for aggregation and chemotaxis, is expressed in normal amounts on granulocyte membranes both before and after irradiation with a HeNe laser. In fact, Laser irradiation preferentially attacks the area of the cellular centrosome that determines a modification of cellular morphology. The electron microscope and immunofluorescence study with a monoclonal antibody have pointed out a disorganization of the microtubules. The alteration of some of the granulocyte functions is correlated to the damage in the centrioles. The granulocyte mitochondrial system and surface membrane remain intact, and this explains the normal production and release of free radicals. Further experiments are necessary to evaluate the clinical application of lasers in various diseases with immunophagocytic pathogenesis.

Definition of CD 11a, b, c, and CD 18 Glycoproteins on Chemotactically Deficient Granulocyte Membranes in Patients Affected by Myeloid Disorders

We studied neutrophil chemotaxis and surface membrane glycoproteins in 12 patients suffering from myeloid disorders with abnormal karyotype using in vitro techniques in all 12. Chromosome studies were also carried out virtually simultaneously. We chose to study only patients showing a deficit of chemotaxis (p less than 0.001). Ten of these patients revealed a clonal chromosome abnormality in most of the leukemic cells. The monoclonal antibody technique using MoAb 60.1, 60.3, 60.5, OKM1, LFA-1 and 9E8 demonstrated normal leukocyte membrane glycoproteins CD 11a, b, c and CD 18 and therefore excludes that an abnormality of these is involved in the pathogenesis of altered leukocyte chemotaxis. No correlation between chemotactic deficit and any specific clonal chromosome abnormality was found.

Lymphocyte and granulocyte phosphatidylethanolamine N-methyltransferase: properties and activity in cystic fibrosis.

Human lymphocyte and granulocyte membranes contain an enzyme, phosphatidylethanolamine N-methyltransferase (PEMT), which catalyzes the transfer of a methyl group from S-adenosylmethionine to the polar head group of phosphatidylethanolamine to form phosphatidylmonomethylethanolamine. This enzyme, in lymphocyte membranes, has Km for S-adenosylmethionine of 7.01 +/- 2.9 (SD) microM, and specific activity 0.57 +/- 0.31 pmol/mg protein/15 min, is inhibited by S-adenosylhomocysteine, displays optimal activity at pH 8.0-9.0, and is stimulated by isoproterenol in dose-dependent, propranolol-inhibitable fashion, to a lesser extent by epinephrine, but not by norepinephrine, prostaglandin E1, concanavalin A, or adenosine 3':5' cyclic monophosphate, with or without phosphodiesterase inhibitors. Granulocyte membrane PEMT has Km for S-adenosylmethionine of 4.4 microM and specific activity 0.54 +/- 0.51 pmol/mg protein/15 min, is inhibited by S-adenosylhomocysteine, displays optimal activity at pH 8.0-9.5, and is stimulated by isoproterenol greater than epinephrine greater than norepinephrine, but not by prostaglandin E1, serum-treated zymosan, formyl-methionyl-leucyl-phenylalanine, or adenosine 3':5' cyclic monophosphate. Because activation of PEMT reportedly contributes to several processes known to be abnormal in cystic fibrosis, including coupling of the beta-adrenergic receptor to adenylate cyclase, activity of PEMT was compared in lymphocyte and granulocyte membrane preparations from cystic fibrosis patients and healthy controls, in which abnormal coupling of beta-adrenergic receptor to adenylate cyclase had been demonstrated. For both cell types, the Km and specific activity of PEMT were comparable in normal and cystic fibrosis samples. Therefore, the hypothesis that reduced PEMT activity accounts for the impaired coupling of beta-adrenergic receptor to adenylate cyclase in lymphocytes and granulocytes in cystic fibrosis is rejected.