bluuebunny/crossref_metadata_2025_split huggingface dataset:
Distinct antigenic features of linear epitopes at the N-terminus and C-terminus of 65 kDa glutamic acid decarboxylase (GAD65): implications for autoantigen modification during pathogenesis
Authors: AL-BUKHARI T A M A , RADFORD P M , BOURAS G , DAVENPORT C , TRIGWELL S M , BOTTAZZO G-F , LAI M , SCHWARTZ H L , TIGHE P J , TODD I 
Published: March 2003

SummaryAutoantibodies to 65 kDa glutamic acid decarboxylase (GAD65) are produced in many patients with autoimmune polyendocrine syndrome type II (APS-II) or stiff-man syndrome (SMS) and are heterogeneous in their epitope specificities, recognizing both conformational and linear determinants. Major linear epitopes of GAD, which are recognized by autoantibodies in a minority of these patients, occur in the N-terminal and C-terminal regions. We have investigated antibody recognition of the N- and C-termini of GAD65 in relation to their structural features as an approach to understanding what modifications to the native GAD structure may occur that facilitate the generation of antibodies specific to linear epitopes in these regions during the autoimmune pathogenesis. A monoclonal antibody specific to the N-terminus of GAD65 bound both native and denatured GAD in ELISA, whereas monoclonal and polyclonal antibodies specific to the C-terminus of GAD bound only denatured GAD. These antibodies were epitope mapped using random peptide phage-display libraries and the epitopes related to a previously proposed structural model of GAD65. This has led us to propose that the α-helical secondary structure of the C-terminus of GAD65 must be denatured to generate linear epitopes. In contrast, the N-terminus is both surface exposed and linear in the native structure, but may be masked by membrane interactions, which must be broken to facilitate recognition by B cells.
Increased expression of mucosal addressin cell adhesion molecule-1 (MAdCAM-1) and lymphocyte recruitment in murine gastritis induced byHelicobacter pylori
Authors: HATANAKA K , HOKARI R , MATSUZAKI K , KATO S , KAWAGUCHI A , NAGAO S , SUZUKI H , MIYAZAKI K , SEKIZUKA E , NAGATA H , ISHII H , MIURA S 
Published: March 2003

SummaryAlthough  T  cell  involvement  in  Helicobactor  pylori-induced  gastritis  is  known,  mechanism  about  T cell recruitment is not understood. In this study we examined how mucosal addressin cell adhesion ­molecule-1 (MAdCAM-1) is involved in lymphocyte recruitment in murine chronic gastritis induced by H. pylori. C57 BL/6 mice were infected with Sydney strain (SS1). Six months after infection, the stomach was removed. The expression of adhesion molecules, MAdCAM-1, intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1), and the cell surface antigens CD4, CD8, CD45R/B220 or β7-integrin were determined by immunohistochemistry. A significant increase in CD4 lymphocytes was observed in the body portion of stomach in SS1-infected mice and most of these CD4 cells express β7-integrin, a known counter ligand for MAdCAM-1 molecule. Strong MAdCAM-1 expression was observed adjacent to these cells in the lamina propria as well as in the submucosa of SS1-infected stomach. Quantitative analysis showed that the area of MAdCAM-1 expression well correlated with the infiltration of β7-integrin positive lymphocytes. On the other hand, expression of ICAM-1 or VCAM-1 in the lamina propria was few even in the SS1-infected stomach. Increased expression of MAdCAM-1 was well correlated to the location of lymphocytes, which express CD4 and β7-integrin. These results suggest the possibility that MAdCAM-1 may be largely involved in the lymphocyte recruitment in the gastritis mucosa with H. pylori.
Nasal administration of CTB-insulin induces active tolerance against autoimmune diabetes in non-obese diabetic (NOD) mice
Authors: ASPORD C , THIVOLET C 
Published: March 2003

SummaryNasal administration of beta cell-derived auto-antigens has been reported to suppress the development of autoimmune diabetes. We investigated the tolerogenic effects of insulin conjugated to the B subunit of cholera toxin (CTB). Nasal administration of 1 µg of CTB-insulin significantly delayed the incidence of diabetes in comparison to CTB treated mice. However, administration of 4 or 8 µg of the conjugate had no protective effect. Protection induced by CTB-insulin was transferred to naive recipients by splenic CD4+ T cells. This result favours an active cellular mechanism of regulation, which was lost using higher (4–8 µg) or lower (0·1–0·5 µg) amounts of the conjugate. When co-administered with diabetogenic  T  cells,  splenic  T  cells  from  CTB-insulin-treated  mice  reduced  the  lymphocytic  infiltration  of the islets. Reverse transcription-polymerase chain reaction analysis of recipients’ pancreatic glands revealed an increase of TGF-β and IL-10 transcripts after donor mice tolerization, while levels of IFN-γ and IL-4 RNAs were unchanged. We observed a significant increase of T cell proliferation after unspecific stimulation in the spleen and pancreatic lymph nodes 24 h after CTB-insulin administration in ­comparison to control treatment. Higher amounts of IL-4 and IFN-γ   were noticed in pancreatic lymph nodes of tolerized mice upon in vitro stimulation. Antigen-specific unresponsiveness after immunization and upon subsequent in vitro exposure to homologous antigen was obtained in nasally treated animals. Our results underlined the importance of nasal mucosa as an inducing site of tolerance and provided evidence for similar mechanisms of action to what has been described for the oral route, which favoured a CTB-insulin specific effect.
Up-regulation of the dendritic cell marker CD83 on polymorphonuclear neutrophils (PMN): divergent expression in acute bacterial infections and chronic inflammatory disease
Authors: IKING-KONERT C , WAGNER C , DENEFLEH B , HUG F , SCHNEIDER M , ANDRASSY K , HÄNSCH G M 
Published: March 2003

SummaryUpon cultivation with interferon-γ (IFN-γ) and granulocyte/macrophage-colony stimulating factor (GM-CSF) polymorphonuclear neutrophils (PMN) acquire characteristics of dendritic cells, including expression of major histocompatibility complex (MHC) class II antigens, of the co-stimulatory antigens CD80, CD86 and of CD83, the latter considered to be specific for dendritic cells. Dendritic-like PMN were also able to present to T cells antigens in a MHC class II-restricted manner. To assess whether dendritic-like PMN are also generated in vivo, cells of patients with acute bacterial infections and of patients with chronic inflammatory diseases (primary vasculitis) were tested. During acute infection up to 80% of PMN acquired CD83, but remained negative for MHC class II, CD80 or CD86. PMN of patients with primary vasculitis expressed MHC class II antigens, CD80 and CD86, but not CD83, indicating that up-regulation of MHC class II and of CD83 are not necessarily linked to each other. Indeed, parallel studies with PMN of healthy donors showed that while IFN-γ and granulocyte/macrophage colony stimulating factor (GM-CSF) induced both, MHC class II and CD83, tumour necrosis factor (TNF)-α selectively induced de novo synthesis of CD83. The function of CD83 on PMN is still elusive. A participation in the MHC class II-restricted antigen presentation could be ruled out, consistent with the segregation of MHC class II and CD83 expression. Regardless, however, of its function, CD83 expression could serve as a marker to differentiate between acute and chronic inflammation.
Induced sputum-retrieved matrix metalloproteinase 9 and tissue metalloproteinase inhibitor 1 in granulomatous diseases
Authors: FIREMAN E , KRAIEM Z , SADE O , GREIF J , FIREMAN Z 
Published: March 2003

SummaryMatrix metalloproteinases (MMPs) capable of degrading various components of connective tissue matrices, and tissue inhibitor metalloproteinases (TIMPs) are considered important in lung parenchymal remodeling and repair processes in pulmonary diseases. Induced sputum (IS) is a reliable noninvasive method to investigate pathogenesis, pathophysiology and treatment of lung disease. This study was designed to determine whether IS-MMP9/TIMP1 levels demonstrate lung parenchymal remodeling in sarcoidosis (SA) and Crohn's disease (CRD) patients. Sputum was induced and processed conventionally in 13 SA patients, 18 CRD patients and 9 controls. Two-hundred cells were counted on Giemsa-stained cytopreps, and T lymphocytes subsets (CD4 = T helper and CD8 = T suppressor cytotoxic cells) were analysed by FACS using monoclonal antibodies.MMP-9 and TIMP-1 were measured using commercial ELISA kits. MMP-9 concentrations, but not those of TIMP-1, were significantly greater in the sputum supernatant in SA and CRD patients compared to controls (P = 0·018 and P= 0·0019, respectively). The molar ratio, MMP-9/TIMP-1, was significantly higher in SA and CRD patients compared to controls (P = 0·008 and P= 0·024, respectively). Gelatinase species having a molecular weight similar to that of MMP-9 were demonstrated by zymographic analysis. MMP-9 levels were highly correlated with the CD4/CD8 ratio and DLCO capacity in SA but less in CRD patients. MMP-9 levels in IS provide a sensitive marker for pulmonary damage.
Interferon-gamma levels in nasopharyngeal secretions of infants with respiratory syncytial virus and other respiratory viral infections
Authors: JOSHI P , SHAW A , KAKAKIOS A , ISAACS D 
Published: March 2003

SUMMARYRespiratory syncytial virus (RSV) infection, one of the most common causes of hospitalization of children in developed countries, has been implicated as a cause of asthma. We aimed to characterize the cytokine profile in nasopharyngeal aspirates (NPAs) taken from infants during upper respiratory tract infection to investigate whether RSV induced a unique immune response as compared with other viruses. Additionally, we sought to determine whether this profile was influenced by the infants’ atopic status. A prospective birth cohort of babies at high risk of atopy was recruited. Ratios of a T-helper 1 (Th1) cytokine, interferon gamma (IFN-γ) and a T-helper 2 (Th2)-like cytokine, interleukin-10 (IL-10), in NPAs were determined during episodes of respiratory tract infections in the first year. The viral aetiology of the respiratory tract infections was determined using polymerase chain reaction (PCR), culture and immunofluorescence. Atopic status was ascertained at 1 year of age using skin prick tests. Participants were recruited antenatally and subsequently followed in the community. Sixty babies with one or both parents atopic were enrolled into the study. IFN-γ : IL-10 ratios in NPAs during upper respiratory tract infections and their correlation with viral aetiology and atopic status were the main outcome measures. The mean IFN-γ : IL-10 ratio was significantly lower (due to lower IFN-γ) during RSV infections than during infections with other viruses (P = 0·035). The cytokine ratio, however, did not differ between infants with or without wheeze during URTIs (P = 0·44), or between infants who were atopic or non-atopic (P = 0·49). This study suggests that RSV is associated with lower IFN-γ production in young babies, regardless of their atopic status, compared to upper respiratory tract infections where either another virus is detected or where no viral identification is made.
Influence ofMycobacterium tuberculosison differential activation of helper T-cells
Authors: TALREJA J , BHATNAGAR A , JINDAL S K , GANGULY N K 
Published: March 2003

SUMMARYHost defence against tuberculosis infection involves T-lymphocyte mediated cellular immune responses. In this study we assessed T-cell activation by studying the early signal transduction events and production of cytokines by human CD4+ T-cells. The study constituted of five groups of subjects: (a) untreated acid fast bacilli (AFB)+ve TB patients who have not started anti-tuberculosis therapy (ATT) [New]; (b) patients who have taken ATT for two months [2T]; (c) patients who have taken ATT for six months [6T]; (d) mantoux positive healthy controls [T+ve]; (e) mantoux negative healthy controls [T−ve]. We found that mantoux positive healthy controls produced significantly higher levels of IP3, intracellular Ca2+ and presented increased PKC activity when CD4+ T-cells were stimulated with M. tuberculosis H37Rv cell lysate as compared to mantoux negative controls. Furthermore, decreased expression of CD54 (ICAM-1) and reduced [Ca2+]i were seen in TB patients as compared to T+ve healthy controls. TB patients showed significantly lower levels of IL-2 and IFNγ and higher levels of IL-4 as compared to normal healthy controls, suggesting a diminished Th1 response. Thus, the reciprocal changes in cytokines, reduced [Ca2+]i levels, and CD54 expression in patients imply phenotype shifting of Th precursors to Th2 type in TB patients.
Analysis of gene expression in peripheral blood eosinophils from patients with atopic dermatitis andin vitrocytokine-stimulated blood eosinophils
Authors: OGAWA K , HASHIDA R , MIYAGAWA M , KAGAYA S , SUGITA Y , MATSUMOTO K , KATSUNUMA T , AKASAWA A , TSUJIMOTO G , SAITO H 
Published: March 2003

SummaryInvestigation of differentially expressed genes in eosinophils of patients with allergic diseases such as atopic dermatitis (AD) will provide important information for elucidating possible mechanisms of pathology. To identify novel genes that are expressed in AD, we compared gene expression in samples of peripheral blood eosinophils from AD patients and healthy volunteers. RNA was extracted from peripheral blood eosinophils. The expression of various genes, such as those for cytokine receptors, eosinophil activation marker, platelet activating factor (PAF) receptor, eosinophil-specific granular proteins and apoptosis-related genes, was confirmed using real-time reverse transcription–polymerase chain reaction (RT-PCR). Peripheral blood eosinophils of healthy volunteers were also isolated and stimulated for introduction of various cytokines. RNA was extracted and gene expression was monitored. Several genes, such as those for cytokine receptors (granulocyte-macrophage colony-stimulating factor (GM-CSF) receptor α and β chain and interleukin (IL)-3 receptor α chain), CD44 and PAF receptor were expressed at significantly higher levels in AD patients than in healthy volunteers. In addition, the anti-apoptotic genes, bcl-2 and bcl-xL, were expressed at increased levels in AD patients. No single gene expression correlated with clinical markers, such as eosinophil count or IgE levels. Expression of GM-CSF receptor β chain and IL-3 receptor α chain in isolated blood eosinophils of healthy volunteers was stimulated by IL-5, IL-4, interferon (IFN)-γ and GM-CSF. Expression of bcl-2 and bcl-xL was also increased after stimulation with IL-5, IL-4 or IFN-γ. The in vitro enhancement of cytokine-stimulated gene expression correlated well with the enhancement observed in clinical samples of eosinophils, suggesting that cytokines may affect gene expression in vivo in eosinophils of patients with AD.
LiveLeishmaniapromastigotes can directly activate primary human natural killer cells to produce interferon-gamma
Authors: NYLÉN S , MAASHO K , SÖDERSTRÖM K , ILG T , AKUFFO H 
Published: March 2003

SummaryNatural killer (NK) cells have been implicated in the natural protection and healing of leishmaniasis by their ability to secrete the macrophage activating cytokine interferon (IFN)γ. Previous studies have demonstrated that early production of interleukin (IL)-12 triggers IFNγ secretion by NK cells. Here we report that live Leishmania promastigotes (the form that is injected by the vector) can directly induce human peripheral blood NK cells from healthy donors to IFNγ secretion in the absence of IL-12 and professional antigen presenting cells. Killing of promastigotes abolishes this property. This novel mechanism of activation of the innate immune response may be relevant for establishment of infection and thus also the design of vaccines against leishmaniasis.
Clinical profile of primary hyperparathyroidism in adolescents and young adults
Authors: Loh Keh‐Chuan , Duh Quan‐Yang , Shoback Dolores , Gee Lauren , Siperstein Allan , Clark Orlo H. 
Published: March 2003

OBJECTIVEPrimary hyperparathyroidism (PHPT) is an uncommonly diagnosed condition among adolescents and young adults. We review the clinical characteristics of these patients based on our institutional experience.SUBJECTSPatients aged 12–28 years treated for PHPT at our institution from 1990 to 1996 were evaluated by a review of medical records and current follow‐up data. This consisted of 22 patients (8M:14F), constituting approximately 3% of all patients operated for PHPT during this period.MEASUREMENTSSerum and urinary calcium concentrations, renal function, and serum intact parathyroid hormone (iPTH) levels were measured in all patients. After biochemical confirmation of diagnosis, the patients completed a questionnaire to evaluate the presence of symptoms and/or conditions associated with PHPT. All the patients underwent parathyroidectomy and their tumour characteristics were evaluated. Surgical outcome was determined by measurements of serum calcium and iPTH levels postoperatively and during long‐term follow‐up.RESULTSA third of the patients were diagnosed by routine serum chemistry whereas two‐thirds presented with symptoms or conditions associated with hypercalcaemia. Non‐specific complaints such as fatigue or exhaustion, and weakness or lethargy constitute the most common findings on questionnaire review. A family history of PHPT was present in only 2 patients. The preoperative peak serum calcium levels ranged from 2.67 to 4.19 mmol/l (norm: 2.10–2.54 mmol/l), with a median of 3.07 mmol/l. Surgical pathologies revealed 59% solitary adenoma, 27% hyperplasia, 9% multiple adenomas and 5% carcinoma. Comparison between the adolescents (aged 12–18 years) and young adults (aged 19–28 years) revealed no differences in the clinical, pathological or laboratory profiles, except for a male predominance in adolescent patients. Fifteen patients had resection of one or more adenomas while 7 underwent subtotal parathyroidectomy. Six patients (27%) were reoperated cases, all received primary treatment elsewhere. All patients with benign PHPT were cured surgically, with a median follow‐up of 47 months (range 3–77 months). One reoperated patient developed permanent hypocalcaemia. One patient with carcinoma underwent several operations for recurrence; he is now eucalcaemic despite persistent disease at 80 months from diagnosis.CONCLUSIONSWe found a high incidence of multiglandular disease and relatively non‐specific symptomatology in our adolescent and young adult patients with primary hyperparathyroidism. In view of the heterogeneous clinical expression noted in young patients, one should consider primary hyperparathyroidism in the differential diagnosis of unexplained non‐specific complaints, and perform serum calcium estimations more readily in these subjects. Our experience suggests that primary hyperparathyroidism can be a serious disease with significant morbidity if left untreated, whereas parathyroidectomy provides successful results.
Prolactinomas express human heparin‐binding secretory transforming gene (hst) protein product: marker of tumour invasiveness
Authors: Shimon Ilan , Hinton David R. , Weiss Martin H. , Melmed Shlomo 
Published: March 2003

BACKGROUND AND OBJECTIVEWe have shown previously that heparin‐binding secretory transforming gene (hst) overexpression in rat pituitary cells mediates lactotroph tumour growth and stimulates PRL transcription, and that transforming sequences of the gene, which encode fibroblast growth factor‐4 (FGF‐4), are expressed in human prolactinomas. To further determine the role of hst in human PRL‐secreting adenoma pathogenesis we studied the presence of hst protein in these tumours and other types of human pituitary adenoma.PATIENTS AND DESIGNPituitary adenoma tissue samples were obtained at surgery from 14 patients with PRL‐secreting adenomas, 5 patients with GH‐secreting tumours, 3 with ACTH‐secreting, and 13 patients with nonfunctioning tumours. Two normal pituitary tissue specimens were also studied. Clinical data, including tumour invasiveness assessed by preoperative MRI studies, were available. For hst protein immunolocalization, tumour frozen sections were immunostained with antihuman FGF‐4 antibody. Immunoperoxidase staining for the proliferation‐related nuclear antigen Ki‐67 was performed using MIB‐1 monoclonal antibody.RESULTSNormal anterior pituitary cells did not contain immunoreactive hst protein. Lactotrophs in five of 14 prolactinomas (36%) stained strongly for hst compared with immunoreactive pituicytes in only one of 21 nonfunctioning, GH‐, and ACTH‐secreting adenomas (P = 0.05). Immunoreactive hst in adenoma cells was detected in 3 of 5 invasive prolactinomas, and in 2 of 9 noninvasive PRL‐cell adenomas. Immunostaining for the proliferation‐related antigen Ki‐67 showed a higher proliferation index in hst‐positive adenomas (3.94 + 0.85%) as compared with those immunonegative for hst (1.98 + 0.7%; P = 0.05).CONCLUSIONShst protein may be directly involved in prolactinoma development or progression, particularly in invasive tumours, probably due to the growth promoting effects of FGF‐4.
Melatonin administration and pituitary hormone secretion
Authors: Kostoglou‐Athanassiou Ifigenia , Treacher David F. , Wheeler Michael J. , Forsling Mary L. 
Published: March 2003

OBJECTIVEThe relationship between the pineal gland and pituitary function remains controversial, while the role of melatonin in the adaptation of the organism to the light‐dark cycle of the environment is becoming increasingly recognized. The aim of this study was to investigate the effect of a manipulation of the melatonin rhythm on pituitary hormone secretion in man.DESIGNDouble‐blind controlled clinical study.SUBJECTSTen adult healthy male volunteers, aged 21–33 years, were studied on two occasions: once after the administration of melatonin 5 mg orally for 4 days at 1700 hours and once after the administration of placebo, at similar times. On the day of each study the subjects undertook their normal duties but refrained from taking heavy exercise, from smoking and drinking alcohol.MEASUREMENTSSerum cortisol, growth hormone, prolactin and plasma vasopressin, oxytocin, melatonin, sodium, potassium, osmolality and packed cell volume were measured over the following 24 hours.RESULTSThe cortisol peak was advanced and prolactin release increased after melatonin administration, while growth hormone was not affected. Vasopressin and oxytocin levels were found to increase during the night in the control study, but the period of the nocturnal increase in vasopressin concentrations was reduced after the administration of melatonin and the nocturnal increase of oxytocin was absent.CONCLUSIONAltering the melatonin rhythm may affect neuroendocrine function, influencing the nocturnal pattern of neurohypophysial hormone secretion, augmenting prolactin release and advancing the peak of cortisol release.