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ID PMID Title PublicationDate abstract
9175912 Gammalinolenic acid and dihomogammalinolenic acid suppress the CD3-mediated signal transdu 1997 Jun Gammalinolenic acid (GLA; 18:3n6) and dihomogammalinolenic acid (DGLA; 20:3n6) suppress lymphocyte activation, and GLA administration reduces joint swelling and tenderness in rheumatoid arthritis patients with active synovitis. In an effort to dissect the mechanisms whereby GLA, DGLA, and other fatty acids influence lymphocyte function, we examined their effects on anti-CD3 monoclonal antibody (mAb)-mediated early signaling events in human T cells. Peripheral blood mononuclear cells from healthy individuals were incubated overnight at 37 degrees C with or without 10 microg/ml fatty acid and then loaded with the calcium binding fluorescent dye indo-1. Fatty acids did not affect the efficiency of indo-1 loading, and they did not alter cell surface membrane expression of the CD3 molecule. Anti-CD3 mAb (G19-4)-induced intracellular calcium [(Ca2+)i] changes were monitored by flow cytometry in negatively selected human T cells. The ratio of violet to blue fluorescence, which is proportional to (Ca2+)i, was measured over time. Cells enriched with GLA and DGLA but not cells enriched with eicosapentaenoic acid (20:5n3) displayed a significant reduction in anti-CD3 mAb-induced early and late (Ca2+)i responses. T cells loaded with GLA, DGLA, or medium alone displayed similar increases in (Ca2+)i in response to the endoplasmic reticulum Ca2(+)-ATPase inhibitor thapsigargin. Anti-CD3 mAb-mediated inositol phosphate production was also diminished in GLA- and DGLA-treated cells. These experiments suggest that GLA and DGLA suppress T cell activation by interfering with early events in the signal transduction pathway.
9061309 An enzyme immunoassay for polymorphonuclear leucocyte-mediated fibrinogenolysis. 1997 Feb Upon stimulation, polymorphonuclear leucocytes (PMNs) release potent serine proteases, i.e. elastase, cathepsin G and proteinase 3, which contribute to the degradation of tissue and plasma components. Here, we describe the development of a plasma test to assess PMN-mediated fibrinogenolysis as a biochemical marker for actual PMN-derived proteolysis in vivo, useful for monitoring therapeutic efficacy, i.e. of elastase inhibitors. We generated a monoclonal antibody (MAb), designated 1-1/B3, with a high affinity for elastase-degraded fibrinogen (EDF). The epitope for 1-1/B3 becomes exposed in a time-dependent manner during digestion of fibrinogen with purified PMN-derived serine proteases and with isolated PMNs in vitro. However, 1-1/B3 does not react with plasma fibrinogen or with fibrin(ogen) degradation products generated by plasmin or by other active proteases that may occur locally, i.e. metalloproteases and lysosomal cathepsins. On the basis of MAb 1-1/B3, we developed a plasma test for the assessment of PMN-mediated fibrin(ogen) degradation products (PMN-FDP). In a panel of control plasmas, we observed concentrations of PMN-FDP of 8.2 +/- 0.9 ng mL-1 (n = 18). These values were increased twofold in patients with alpha 1-proteinase inhibitor deficiency (18.6 +/- 3.3 ng mL-1; n = 12; P < 0.0001) and even more in patients with sepsis (365.7 +/- 97.7 ng mL-1; n = 16; P < 0.0001). Furthermore, synovial tissue extracts from patients with rheumatoid arthritis contained increased levels of PMN-FDP, compared with synovial tissue extracts (P < 0.005) from patients with osteoarthritis.
9310825 Monocyte-dependent regulation of T lymphocyte activation through CD98. 1997 Sep CD98 is a 125 kDa heterodimer, which is strongly expressed on the surface of activated and proliferating cells. Its expression is strikingly regulated during T cell differentiation and activation, but the role of CD98 during T lymphocyte responses is not yet understood. We report here that proliferation of resting peripheral blood mononuclear cells (PBMC) induced by lectin, superantigen (SAg) or conventional antigens was blocked by anti-CD98 heavy chain (CD98hc) mAb. In contrast, anti-CD98hc did not block responses of T cell clones or lines. Anti-CD98hc inhibited IL-2 receptor expression and progression of T cells from G1 to S phase, but did not reduce expression of the IL-2 gene. Anti-CD98hc mAb did not regulate the initial activation events involving the TCR and co-receptor structures, but instead inhibited T lymphocyte responses even when added 18 h or more after the activation stimulus. Further experiments demonstrated that anti-CD98 was not directly affecting T cells in this system, but was instead acting on accessory cells. This was supported using a novel xenogeneic system that takes advantage of the lack of xenoreactivity of purified human T cells against mouse splenocytes. Despite absence of a direct xenoresponse to murine spleen cells, human T cells were activated by SAg presented by murine splenic antigen-presenting cells (APC). Murine anti-human CD98hc did not block T cell proliferation in this system. Furthermore, responses using monocyte-depleted PBMC as APC were not blocked by anti-CD98hc. Taken together, the present data suggests that triggering of human monocyte CD98 can suppress T cell proliferation by a process that halts progression through the cell cycle of recently activated T lymphocytes. This may represent a novel pathway for monocyte regulation of T cell activation.
9839926 A major Sm epitope anchored to sequential oligopeptide carriers is a suitable antigenic su 1998 Nov 1 A sensitive, highly reproducible, solid-phase enzyme immunoassay (ELISA), was developed in order to investigate whether the synthetic heptapeptide PPGMRPP-a major epitope of the Sm autoantigen-anchored in five copies to a sequential oligopeptide carrier (SOC), [(PPGMRPP)5-SOC5] is a suitable antigenic substrate to identify anti-Sm/antibodies. Sera with different autoantibody specificities [45 anti-Sm, 40 anti-U1RNP, 40 anti-Ro (SSA)/La(SSB) positive, 21 Antinuclear antibody positive, but negative for antibodies to extractable nuclear antigens (ANA + /ENA - ) and 75 normal human sera, ANA negative] and 75 sera from patients with rheumatoid arthritis (RA) were tested for anti-(PPGMRPP)5-(SOC)5 reactivity in order to evaluate the specificity and sensitivity of the method to detect anti-Sm antibodies. RNA immunoprecipitation assays for the detection of anti-Sm and anti-U1RNP antibodies and counter immunoelectrophoresis (CIE) for the detection of anti-Ro(SSA) and anti-La(SSB) antibodies were used as reference techniques. The sensitivity of the method was 98% and the specificity was 68% for the determination of anti-Sm antibodies, while for the determination of anti-Sm and/or anti-U1RNP reactivity (antibodies to snRNPs) the corresponding values were 82% and 86%, respectively. In a comparison of the above assay with an ELISA, using Sm/U1RNP purified complex as immobilized antigen it was shown that the sensitivity of the anti-Sm/U1RNP ELISA in detecting anti-snRNPs was 74%; in addition sera with anti-Sm antibodies gave higher binding in the anti-(PPGMRPP)5-(SOC)5 ELISA compared with anti-Sm/U1RNP ELISA. Intra- and inter-assay precision was measured on four sera with reactivities extending into a wide range of absorbance values showed that the intra-assay coefficient of variation (CV%) ranged from 2.7 to 6 and the inter-assay CV% ranged from 9 to 14.5. These results indicate that the PPGMRPP peptide anchored to a pentameric SOC as a carrier is a suitable antigen for detecting anti-Sm antibodies and that the above ELISA is a rapid, reproducible and valuable screening method to test anti-Sm/U1RNP reactivities.
9780181 The role of Ets-1 in mast cell granulocyte-macrophage colony-stimulating factor expression 1998 Oct 15 Ets-1 is a transcription factor with restricted expression in lymphocytes, and it has been implicated in the regulation of T cell genes such as TCR alpha, TCR beta, CD4, IL-2, and TNF-alpha. We show in this study that Ets-1 is also expressed in some mast cells constitutively and can be induced in primary mast cells with stimuli that activate mast cells. We also show that Ets-1 plays a role in the regulation of granulocyte-macrophage CSF (GM-CSF), a cytokine expressed by activated mast cells. We have characterized a murine growth factor-independent mast cell line, FMP6-, derived from a factor-dependent cell line, FMP1.6. FMP6- has acquired a distinct connective tissue mast cell-like phenotype, as characterized by the expression of mast cell proteases MMCP-4 and MMCP-6, expression of IL-12, and the down-regulation of IL-4. The parental FMP1.6 cell line displays a mucosal mast cell-like phenotype. FMP6- cells have increased Ets-1 expression and achieve growth-factor independence by the autocrine production of GM-CSF and IL-3. Transient transfection of an Ets-1 expression construct in FMP6- cells results in transactivation of a GM-CSF reporter, while a point mutation in the consensus Ets binding site in the conserved lymphokine element, CLE0, abolishes Ets-1 transactivation. Importantly, antisense Ets-1 demonstrates an ability to repress the activity of the GM-CSF reporter. These data suggest a role for Ets-1 in mast cell growth regulation and activation, and because of the central role of mast cells in inflammatory processes, such as asthma and rheumatoid arthritis, they identify Ets-1 as potentially contributing to the pathophysiology of such diseases.
9623824 Silicon analysis of breast and capsular tissue from patients with saline or silicone gel b 1998 Jun The silicone breast implant controversy rages on. Recent work has demonstrated that normal or baseline breast tissue silicon levels in women who had had no prior exposure to any type of breast implant may be as high as 446 microg/gm of tissue. These data ranged from 4 to 446 microg/gm of tissue, with a median of 27.0 microg/gm of tissue. In addition, numerous other epidemiologic and rheumatologic studies have demonstrated no association between silicone breast implants and any connective-tissue diseases. Despite these reports, the use of silicone implants remains restricted. The present study measured breast and capsular tissue silicon levels from 23 breasts in 14 patients with saline implants, and from 42 breasts in 29 patients with silicone implants. No patient in the saline implant group presented with signs or symptoms of connective-tissue disease. Patients with silicone implants, however, were divided into three groups based on the presence or absence of signs or symptoms of connective-tissue disease: group I, no symptoms or signs; group II, + symptoms, no signs; and group III, + symptoms, + signs. Six patients in group III were diagnosed with a specific connective-tissue disease, including systemic lupus erythematosus, rheumatoid arthritis, or scleroderma. The most common indications for implant removal or exchange were capsular contracture and implant rupture, although 41 percent of patients with silicone implants expressed media-related concern over the implant issue. The most common symptoms described by patients in groups II and III were joint pain and stiffness, arm pain and numbness, and fatigue. In all groups, capsular tissue silicon levels were significantly greater than breast tissue levels. This finding may indicate that the capsule serves as a barrier to the distribution of silicone from the implant into adjacent breast tissue. Although breast tissue silicon levels in patients with silicone implants were not significantly greater than those in patients with saline implants (p = 0.48), capsular tissue levels in patients with silicone implants were, indeed, significantly greater than those in patients with saline implants (p < 0.001). However, no statistically significant differences in tissue silicon levels were observed with relation to the presence or absence of connective-tissue disease signs or symptoms in patients with silicone implants (groups I to III). Therefore, these data strengthen the conclusion that there is no association between tissue silicon levels and connective-tissue disease.
9539788 An antagonistic vascular endothelial growth factor (VEGF) variant inhibits VEGF-stimulated 1998 Apr 14 Vascular endothelial growth factor (VEGF) is a potent mitogen with a unique specificity for endothelial cells and a key mediator of aberrant endothelial cell proliferation and vascular permeability in a variety of human pathological situations, such as tumor angiogenesis, diabetic retinopathy, rheumatoid arthritis, or psoriasis. VEGF is a symmetric homodimeric molecule with two receptor binding interfaces lying on each pole of the molecule. Herein we report on the construction and recombinant expression of an asymmetric heterodimeric VEGF variant with an intact receptor binding interface at one pole and a mutant receptor binding interface at the second pole of the dimer. This VEGF variant binds to VEGF receptors but fails to induce receptor activation. In competition experiments, the heterodimeric VEGF variant antagonizes VEGF-stimulated receptor autophosphorylation and proliferation of endothelial cells. A 15-fold excess of the heterodimer was sufficient to inhibit VEGF-stimulated endothelial cell proliferation by 50%, and a 100-fold excess resulted in an almost complete inhibition. By using a rational approach that is based on the structure of VEGF, we have shown the feasibility to construct a VEGF variant that acts as an VEGF antagonist.
11838958 Down-regulation of cell adhesion molecules LFA-1 and ICAM-1 after in vitro treatment with 2001 Nov The tumor necrosis factor-alpha (TNF-alpha) inhibitor thalidomide is known to be a potent modulator of host immunity, a potential treatment for autoimmune disorders such as rheumatoid arthritis (RA) and a treatment for complications of HIV-1 infection. RA is an autoimmune disease of the joints that has been associated with hyperactivity of lymphocytes and other leukocytes, over-expression of pro-inflammatory cytokines (TNF-alpha and IL-1) and chronic debilitating inflammation. Thalidomide may play a role in RA treatment by altering leukocyte function through down-modulation of cell adhesion molecules necessary for leukocyte migration to inflammatory sites. The present study investigates down-regulation of cell adhesion molecules (ICAM-1 and LFA-1) and decreases in cell-cell contacts between human T leukemic (CEM) cells and human umbilical vein endothelial cells (HUVEC) after thalidomide exposure. CEM cells were cultured in RPMI 1640 medium with 0, 10 or 50 microg/ml thalidomide, stained with fluorescent monoclonal antibodies specific to ICAM-1 and LFA-1 and expression was measured with flow cytometry. For cell-cell adhesion measurements, monolayers of HUVEC cultured in Kaign's F-12 medium were incubated with thalidomide treated CEM cells stained with calcein AM. Specific cell adhesion between the two cell types was visualized with fluorescence microscopy. Thalidomide treatment significantly reduced cell adhesion molecule expression in a dose-dependent fashion and inhibited HUVEC/CEM cell adhesion. These data support the hypothesis that thalidomide has modulatory actions on leukocyte functions through expression of cell adhesion molecules.
11677200 Etanercept for active Crohn's disease: a randomized, double-blind, placebo-controlled tria 2001 Nov BACKGROUND & AIMS: We evaluated etanercept, a human soluble tumor necrosis factor receptor: Fc fusion protein, for the treatment of active Crohn's disease. METHODS: Forty-three patients with moderate to severe Crohn's disease were enrolled in an 8-week placebo-controlled trial. Patients were randomized to subcutaneous etanercept 25 mg or placebo twice weekly. The primary outcome measure was clinical response at week 4, defined as a decrease in the baseline Crohn's Disease Activity Index score > or =70 points or a Crohn's Disease Activity Index score <150 points. RESULTS: At week 4, 39% of etanercept-treated patients had clinical response as compared with 45% of placebo-treated patients (P = 0.763). The frequency of common adverse events including headache, new injection site reaction, asthenia, abdominal pain, Crohn's disease-related anemia, and skin disorders was similar in both groups. Likewise, the frequency of severe or serious adverse events was similar in both groups. CONCLUSIONS: Subcutaneous etanercept at a dose of 25 mg twice weekly is safe, but not effective, for the treatment of patients with moderate to severe Crohn's disease. The dose of etanercept administered in this study is that approved for rheumatoid arthritis. Higher doses or more frequent dosing may be required to attain a response in patients with active Crohn's disease.
11329612 Establishment and characterization of chondrocyte cell lines from the costal cartilage of 2001 Complete understanding of the physiology and pathology of the cartilage is essential to establish treatments for a variety of cartilage disorders and defects such as rheumatoid arthritis, congenital malformations, and tumors of cartilage. Although synthetic materials have been used in many cases, they possess inherent problems including wear of the materials and low mechanical strength. Autograft has been considered very effective to overcome these problems. However, the limitation of the transplant volume is a major problem in autograft to be overcome. The costal cartilage is the most serious candidate for donor site transplantation, since it is the largest permanent hyaline cartilage in the body. To investigate the possibility using the costal cartilage as a transplant source, we have established and characterized three mouse chondrocyte cell lines (MCC-2, MCC-5, and MCC-35) derived from the costal cartilage of 8-week-old male SV40 large T-antigen transgenic mice. At confluence, all the cell lines formed nodules that could be positively stained with alcian blue (pH 2.5). The size of nodules gradually increased during culturing time. After 2 and 6 weeks of culture, RT-PCR analysis demonstrated that all three cell lines expressed mRNA from the cartilage-specific genes for type II collagen, type XI collagen, aggrecan, and link protein. Furthermore, type X collagen expression was detected in MCC-5 and MCC-35 but not in MCC-2. Any phenotypic changes were not observed over 31 cell divisions. Immunocytochemistry showed further that MCC-2, MCC-5, and MCC-35 produced cartilage-specific proteins type II collagen and type XI collagen, while in addition MCC-5 and MCC-35 produced type X collagen. Treatment with 1alpha, 25-dihydroxyvitamin D(3) inhibited cell proliferation and differentiation of the three cell lines in a dose-dependent manner. These phenotypic characteristics have been found consistent with chondrocyte cell lines established from cartilage tissues other than costal cartilage. In conclusion, costal cartilage shows phenotypic similarities to other cartilages, i.e., articular cartilage and embryonic limbs, suggesting that costal cartilage may be very useful as the donor transplantation site for the treatment of cartilage disorders. Furthermore, the cell lines established in this study are also beneficial in basic research of cartilage physiology and pathology.
11310382 Role of autoimmunity in nonviral chronic liver disease. 2000 Nov OBJECTIVE: To evaluate the prevalence and clinical profile of autoimmune hepatitis (AIH) in patients with chronic liver disease. METHODS: Four hundred and thirty five consecutive patient with chronic liver disease seen in our department from January 1997 to December 1998 were studied with detailed history and clinical examination. All the patients underwent liver function tests, ultrasonography, isotope liver scanning, viral markers, autoimmune markers ANA, ASMA, LKM1 and AMA (by immunofluorescence technique) and liver histology whenever permissible. Appropriate work up for Wilson's disease was done whenever suspected clinically. Diagnosis of autoimmune hepatitis was made by the composite scoring system by international autoimmune hepatitis group. Twenty out of the 435 patients met the criteria of definite autoimmune hepatitis and seven patient had probable autoimmune hepatitis. Forty out of 408 patients showed markers of autoimmunity positive but did not qualify diagnosis of AIH on composite scores. RESULTS: Demographic profile of 27 patients with autoimmune hepatitis was as follows; male:female ratio 1:8, mean age 39.8 +/- 13 years (Range 4-65 years); mode of presentation as cirrhosis 11/27 (40.7%), chronic hepatitis 12/27 (44.4%) and acute hepatitis 4/27 (14.8%). Elevated serum bilirubin levels were seen in 12 (44.4%) patients while mean serum aminotransferases levels were 249 +/- 343 and 262 +/- 418 respectively. Other disease associations seen were as follows: diabetes in 4 (14.8%), rheumatoid arthritis in 3 (11%), hypothyroidism in 2 (7.4%) and ulcerative colitis in 1 (3.7%). The pattern of autoimmune markers was ANA +ve 23/27 (85%) (+ve titres of ANA > 1:80 in adults and 1:20 in children), ASMA +ve in 16/27 (59.2%) (+ve titres of ASMA > 1:40) and LKM1 in 3 patients. AMA in tires less than 1:80 was found in 3 patients. Liver histology changes seen were lymphoplasmacytic infiltrates (100%), bridging necrosis (93%), liver cell rossetting (80%) and fibrosis with or without cirrhosis (50%). CONCLUSION: Autoimmune liver disease is not uncommon in India and should be suspected in all patients with chronic liver disease, especially in non-viral, non-alcoholic, female patients. The diagnosis of AIH should however be made on the composite scoring system given by international group and not only on the presence or absence of autoimmune markers.
11297551 Inhibition of NF-kappa B activity by thalidomide through suppression of IkappaB kinase act 2001 Jun 22 The sedative and anti-nausea drug thalidomide, which causes birth defects in humans, has been shown to have both anti-inflammatory and anti-oncogenic properties. The anti-inflammatory effect of thalidomide is associated with suppression of cytokine expression and the anti-oncogenic effect with inhibition of angiogenesis. It is presently unclear whether the teratogenic properties of thalidomide are connected in any way to the beneficial, anti-disease characteristics of this drug. The transcription factor NF-kappaB has been shown to be a key regulator of inflammatory genes such as tumor necrosis factor-alpha and interleukin-8. Inhibition of NF-kappaB is associated with reduced inflammation in animal models, such as those for rheumatoid arthritis. We show here that thalidomide can block NF-kappaB activation through a mechanism that involves the inhibition of activity of the IkappaB kinase. Consistent with the observed inhibition of NF-kappaB, thalidomide blocked the cytokine-induced expression of NF-kappaB-regulated genes such as those encoding interleukin-8, TRAF1, and c-IAP2. These data indicate that the therapeutic potential for thalidomide may be based on its ability to block NF-kappaB activation through suppression of IkappaB kinase activity.
11201597 Aortic aneurysm in patients with autoimmune diseases treated with corticosteroids. 2000 Sep BACKGROUND: Aortic aneurysm is a rare but life-threatening cardiovascular complication in patients with autoimmune disorders. The purpose of this study was to clarify the characteristic clinical features and the pathological mechanism of aneurysmal formation in those patients treated with corticosteroids. METHODS: Among 429 patients operated on for abdominal aortic aneurysm during the past 10 years, six patients with autoimmune diseases treated with corticosteroids (one with progressive systemic sclerosis, one with rheumatoid arthritis and four with systemic lupus erythematosus) were reviewed retrospectively. Their data were compared with those of 391 patients with atherosclerotic aneurysms with no autoimmune disorders. The resected aneurysmal walls of the six patients were also compared histopathologically with those of the last six consecutive patients in the control group. RESULTS: The average age of the patients with autoimmune disease was younger than that of the control group (53.8+/-16.6 vs 71.8+/-7.8 years; p<0.05). Patients with autoimmune disease had received long-term corticosteroid therapy for 15-32 years; mean 22.2+/-6.5 years. Pathological examination showed that the destructive change of the medial elastic lamina in the autoimmune disease group was wider than that in the controls. Most patients had no complications in the postoperative follow-up period (5.1+/-3.2 years), while one patient died of rupture of a dissecting aneurysm two years after operation. CONCLUSIONS: Prolonged corticosteroid treatment probably plays a major role in the disintegration of connective tissue of the media, possibly together with primary aortic wall involvement and/or vasculitic damage in patients with autoimmune disorders, which can result in aortic aneurysmal enlargement.
11168393 Unmasking a hyaluronan-binding site of the BX(7)B type in the H3 heavy chain of the inter- 2001 Feb The inter-alpha-inhibitor (I alpha I) family gathers together several plasma protease inhibitors such as I alpha I and pre-alpha-inhibitor (P alpha I) that are variously assembled from a set of polypeptide chain precursors designated H1P to H3P. In addition to their protease inhibitory activity, a major physiological function of I alpha I family members is hyaluronan (HA) binding and HA-dependent stabilization of the extracellular matrix surrounding various cell types. Also, binding of HA to these molecules has been shown to be an important event in tumor cell proliferation and rheumatoid arthritis. However, how HA and I alpha I family members first recognize each other has so far remained elusive. The so-called BX7B domain found in some HA-binding proteins is an HA-binding site in which B represents a basic amino-acid residue and X represents any nonacidic residue. This domain has now been identified in the N-terminal end of H3P that is a precursor of P alpha I. A series of wild-type or mutant recombinant H3P chains produced with a mouse cDNA expressed in Escherichia coli allowed us to demonstrate that this domain binds HA in a noncovalent fashion. Furthermore, unmasking this HA-binding activity required most of H3P to be trimmed off at its C-terminal end. The latter observation was confirmed with a natural, mature H3 chain purified from human plasma. Indeed, a thermolysin-generated, N-terminal fragment of this H3 chain strongly bound HA whereas the intact H3 chain did not. Therefore, in vivo, the HA-binding activity of the mature H3 chain within P alpha I may vary with the folding and/or fragmentation of this protein.
11029607 N-acetylcysteine replenishes glutathione in HIV infection. 2000 Oct BACKGROUND: Glutathione (GSH) deficiency is common in HIV-infected individuals and is associated with impaired T cell function and impaired survival. N-acetylcysteine (NAC) is used to replenish GSH that has been depleted by acetaminophen overdose. Studies here test oral administration of NAC for safe and effective GSH replenishment in HIV infection. DESIGN: Oral NAC administration in a randomized, 8-week double-blind, placebo-controlled trial followed by optional open-label drug for up to 24 weeks. SUBJECTS: HIV-infected, low GSH, CD4 T cells < 500 micro L(-1), no active opportunistic infections or other debilitation; n = 81. Study conducted prior to introduction of protease inhibitors. RESULTS: Whole blood GSH levels in NAC arm subjects significantly increased from 0.88 mM to 0.98 mM, bringing GSH levels in NAC-treated subjects to 89% of uninfected controls (P = 0.03). Baseline GSH levels in the placebo group (0.91) remained essentially the same during the 8 week placebo-controlled trial. T cell GSH, adjusted for CD4 T cell count and beta2-microglobulin levels, also increased in the NAC-treated subjects (P = 0.04). Adverse effects were minimal and not significantly associated with NAC ingestion. CONCLUSION: NAC treatment for 8 weeks safely replenishes whole blood GSH and T cell GSH in HIV-infected individuals. Thus, NAC offers useful adjunct therapy to increase protection against oxidative stress, improve immune system function and increase detoxification of acetaminophen and other drugs. These findings suggest that NAC therapy could be valuable in other clinical situations in which GSH deficiency or oxidative stress plays a role in disease pathology, e.g. rheumatoid arthritis, Parkinson's disease, hepatitis, liver cirrhosis, septic shock and diabetes.
10941877 Effect of low-to-moderate amounts of dietary fish oil on neutrophil lipid composition and 2000 Jul Although essential to host defense, neutrophils are also involved in numerous inflammatory disorders including rheumatoid arthritis. Dietary supplementation with relatively large amounts of fish oil [containing >2.6 g eicosapentaenoic acid (EPA) plus 1.4 g docosahexaenoic acid (DHA) per day] can attenuate neutrophil functions such as chemotaxis and superoxide radical production. In this study, the effects of more moderate supplementation with fish oil on neutrophil lipid composition and function were investigated. The rationale for using lower supplementary doses of fish oil was to avoid adverse gastrointestinal problems, which have been observed at high supplementary concentrations of fish oil. Healthy male volunteers aged <40 yr were randomly assigned to consume one of six dietary supplements daily for 12 wk (n = 8 per treatment group). The dietary supplements included four different concentrations of fish oil (the most concentrated fish oil provided 0.58 g EPA plus 1.67 g DHA per day), linseed oil, and a placebo oil. The percentages of EPA and DHA increased (both P < 0.05) in neutrophil phospholipids in a dose-dependent manner after 4 wk of supplementation with the three most concentrated fish oil supplements. No further increases in EPA or DHA levels were observed after 4 wk. The percentage of arachidonic acid in neutrophil phospholipids decreased (P < 0.05) after 12 wk supplementation with the linseed oil supplement or the two most concentrated fish oil supplements. There were no significant changes in N-formyl-met-leu-phe-induced chemotaxis and superoxide radical production following the dietary supplementations. In conclusion, low-to-moderate amounts of dietary fish oil can be used to manipulate neutrophil fatty acid composition. However, this may not be accompanied by modulation of neutrophil functions such as chemotaxis and superoxide radical production.
10599887 Allele typing of human TNFA 5'-flanking region using polymerase chain reaction-preferentia 1999 Nov Tumor necrosis factor alpha plays a substantial role in a number of conditions such as inflammation, autoimmunity, insulin resistance and sleep. Three new single nucleotide polymorphisms, -1,031 T/C, -863 C/A and -857 T/C, were recently identified in the upstream 5'-flanking region of TNFA in the Japanese population. In the present study, we developed polymerase chain reaction (PCR)-preferential homoduplex formation assay for the single-step allele typing of TNFA, and determined the genotypes of 271 healthy unrelated Japanese individuals. Four haplotypes, -1,031/-863/-857 TCC, TCT, CAC and CCC, were found to constitute the majority, if not all, of the TNFA alleles of healthy Japanese population. These alleles were designated as TNFA-U01, -U02 -U03 and -U04, respectively, in the order of frequency. Based on HLA-A, -B and -DRB1 genotypes together with TNFA genotypes, multi-locus haplotypes were analyzed. Significant positive associations were observed between TNFA-U01 and A*3303, B*5201, B*4403, B*4601, B*0702, DRB1*1502, DRB1*0101, DRB1*1302, between TNFA-U02 and B*5401, B*3501, DRB1*0405, DRB1*0407, between TNFA-U03 and B*4006, B*4002, DRB1*0803, DRB1*0802, DRB1*0403, DRB1*0901, and between TNFA-U04 and B*4801. Four-locus haplotype estimation revealed that A*3303-B*4403-TNFA-U01-DRB1*1302, A*2402-B*5201-TNFA-U01-DRB1*1502 and A*2402-B*5401-TNFA-U02-DRB1*0405 constitute major extended haplotypes in Japanese. Interestingly, TNFA alleles previously shown to have a higher promoter activity (U02, U03) were found to form haplotypes with certain DRB1 alleles associated with T helper 1 (Th1)-dominant diseases such as rheumatoid arthritis, insulin dependent diabetes mellitus and Crohn's disease in Japanese. In contrast, TNFA allele with a low promoter activity (U01) is in linkage disequilibrium with the DRB1 alleles associated with T helper 2 (Th2)-dominant diseases such as atopic dermatitis and ulcerative colitis. These observations raise the possibility that TNFA upstream promoter region polymorphisms contribute to some of the HLA-disease associations.
9861620 Immunoscintigraphy (BW 250/183) in neonates and infants with fever of unknown origin. 1998 Nov Fever of unknown origin is defined as a temperature above 39.0 degrees C together with a white blood cell count > or = 15,000 mm-3, the duration of fever exceeding 2 weeks and a correct diagnosis not being obtained in the first week of hospitalization. In neonates and infants with fever of unknown origin, the localization of the infectious focus is often difficult and unsatisfactory. In this retrospective study, the clinical value of 99Tcm-labelled antigranulocyte antibodies for this group of patients was investigated. Thirty-two immunoscintigrams were performed using 185-259 MBq 99Tcm-labelled antigranulocyte antibodies (BW 250/183) in 30 neonates and infants (21 boys, 9 girls, mean age 29.4 +/- 2 months), who had fever of unknown origin. Immunoscintigraphy was carried out as whole-body images (n = 7) or single planar images (n = 25) 4 h and 24 h post-injection. In children with known cardiac failure, single photon emission tomography of the thorax was performed to diagnose endocarditis (n = 2). For verification, the results of the immunoscintigrams were compared with radiology (conventional radiography = 14, MRI = 5, CT = 3), biopsy (n = 2), blood culture (n = 10) and clinical follow-up after specific therapy. In 11 of 30 children (36%), the diagnosis of an infective focus was possible with immunoscintigraphy. The sensitivity and specificity of diagnosing infective foci was 72% and 95% respectively (n = 11; colitis = 2, infection of the central permanent catheter tip = 2, middle ear infection = 1, spondylitis/discitis = 3, osteomyelitis = 2, umbilical infection = 1). In vertebral body infections, all lesions were photopenic. In 18 children (60%), no infective focus was found on immunoscintigraphy. In this group of children, the main reason (n = 5) for fever of unknown origin was chronic juvenile rheumatoid arthritis. No uptake was seen in two infants with cardiac failure and suspected endocarditis on SPET. In 3 of the 18 patients (17%), localization of an infective focus was not possible with immunoscintigraphy or on other examinations. In these patients, the fever disappeared spontaneously after a few days of antibiotic therapy. In conclusion, we have shown that 99Tcm-anti-NCA-95 scanning is a safe method with a high sensitivity and specificity for detecting infectious foci in neonates and infants with fever of unknown origin. Furthermore, this method is easy to perform, since no withdrawal of blood is necessary.
9442070 The glycosylation and structure of human serum IgA1, Fab, and Fc regions and the role of N 1998 Jan 23 The human serum immunoglobulins IgG and IgA1 are produced in bone marrow and both interact with specific cellular receptors that mediate biological events. In contrast to IgA1, the glycosylation of IgG has been well characterized, and its interaction with various Fc receptors (Fc Rs) has been well studied. In this paper, we have analyzed the glycosylation of IgA1 and IgA1 Fab and Fc as well as three recombinant IgA1 molecules, including two N-glycosylation mutants. Amino acid sequencing data of the IgA1 Fc O-glycosylated hinge region indicated that O-glycans are located at Thr228, Ser230, and Ser232, while O-glycan sites at Thr225 and Thr236 are partially occupied. Over 90% of the N-glycans in IgA1 were sialylated, in contrast to IgG, where < 10% contain sialic acid. This paper contains the first report of Fab glycosylation in IgA1, and (in contrast to IgG Fab, which contains only N-linked glycans) both N- and O-linked oligosaccharides were identified. Analysis of the N-glycans attached to recombinant IgA1 indicated that the Cα 2 N-glycosylation site contained mostly biantennary glycans, while the tailpiece site, absent in IgG, contained mostly triantennary structures. Further analysis of these data suggested that processing at one Fc N-glycosylation site affects the other. Neutrophil Fcα R binding studies, using recombinant IgA1, indicated that neither the tailpiece region nor the N-glycans in the C alpha 2 domain contribute to IgA1-neutrophil Fcα R binding. This contrasts with IgG, where removal of the Fc N-glycans reduces binding to the Fcγ R. The primary sequence and disulfide bond pattern of IgA1, together with the crystal structures of IgG1 Fc and mouse IgA Fab and the glycan sequencing data, were used to generate a molecular model of IgA1. As a consequence of both the primary sequence and S-S bond pattern, the N-glycans in IgA1 Fc are not confined within the inter-α-chain space. The accessibility of the Cα 2 N-glycans provides an explanation for the increased sialylation and galactosylation of IgA1 Fc over that of IgG Fc N-glycans, which are confined in the space between the two Cγ 2 domains. This also suggests why in contrast to IgG Fc, the IgA1 N-glycans are not undergalactosylated in rheumatoid arthritis.
9311285 [Human parvovirus B19 infection mimicking systemic lupus erythematosus: case report]. 1997 Aug Human parvovirus B19 (HPV-B19) has been known as the etiologic agents of erythema infectiosum in normal childhood, and chronic anemia and thrombocytopenia in immuno-compromised patients. Recently, this virus has been reported as the association with rheumatic manifestation such as rheumatoid arthritis and systemic lupus erythematosus (SLE). We described here a patient whose HPV-B19 infection was mimiking atypical symptoms of SLE at diagnosis, and was persistent because of immuno-suppressive therapy for SLE. A 34-year-old female was admitted to our hospital on 22 June 1995, presenting fever episode and cervical lymph node swelling. Before eighteen months, she was received methyl-predonisolone pulse therapy and plasma exchange by fresh frozen plasma for the treatment of Stevens-Johnson syndrome, and after several weeks these therapy she was suffered from viral infection with lymphadenopathies with a transient appearance of atypical lymphocytes in her peripheral blood smear. On laboratory examination at the present admission, her peripheral blood showed anemia, thrombocytopenia with atypical lymphocytes. Throughout her hospitalization, anti-nuclear antibody (ANA) suspected SLE including anti-DNA and anti-Sm antibody were all negative except of transient week positive ANA screening test. Her physical condition presented poor clinical course with fever elevation, increased ascites and renal dysfunction showing the elevation of CRP and circulating immune-complex (Clq binding method). Her serum was positive for IgM and IgG antibody against VP-1 and VP-2 antigen of HPV-B19 by ELISA in April 1996. And then, HPV-B19 DNA by polymerase chain reaction (PCR) was positive in bone marrow sample in March 1996, and also positive in spleen necropsy at death. We confirmed persistent chronic HPV-B19 infection by measurement of HPV-B19 IgM and IgG antibody by ELISA and HPV-B19 DNA by PCR. The plasmapheresis and administration of intravenous immunoglobulin showed the possible efficacy for her symptom throughout this clinical course. Moreover, bone marrow smear showed the finding of virus-associated hemophagocytic syndrome, and finally, she was died of cervical hemorrhage accompanied with disseminated intravascular coagulation syndrome on July 1996. HPV-B19 infection can present an atypical clinical picture that is highly suggestive of SLE. We suggest that the therapy of steroids and immuno-suppressive agents should be cautious, because these may potentially cause persistent chronic HPV-B19 infection and induced life-threatening clinical course.