bluuebunny/crossref_metadata_2025 huggingface dataset:
Anti‐avian antibodies and rheumatoid factor in pigeon hypersensitivity pneumonitis
Authors: Aguilar León D. E. , Novelo Retana V. , Martínez‐Cordero E.
Published: March 2003

Background Although several immunological abnormalities may be present in pigeon hypersensitivity pneumonitis (HP), few specific hallmarks have been described.

Objective To determine whether the presence of rheumatoid factor (RF) could be useful to discriminate pigeon HP from asymptomatic breeders (AB) and other interstitial lung diseases.

Methods Fifty‐three patients with pigeon HP, 47 AB, 31 idiopathic pulmonary fibrosis (IPF) patients and a rheumatoid arthritis (RA) group were studied. IgM RF was determined through enzyme‐linked immunosorbent assay (ELISA) and western blot using human IgG and IgG Fc fragment as antigens. IgG and IgA anti‐avian antibodies (AA) against pigeon serum antigen were also measured. The use of F(ab′)2 fraction of peroxidase‐labelled anti‐human immunoglobulins prevented endogenous interferences. Possible cross‐binding of RF with avian antigens and the reactivity against human IgG by AA were studied.

Results RF tests were frequently positive in HP (52.8%) in comparison to AB (4.2%) and IPF (12.9%; P = 2.6 × 10−10 and 4.1 × 10−5). Therefore, the presence of RF in pigeon HP showed a sensitivity of 52% and was highly specific considering the results of AB and IPF (95 and 87%, respectively). The RA group revealed positive RF but negative AA tests. RF activity was confirmed through western blot using purified IgG Fc fragment. Overlapping levels of IgG and IgA AA were found in HP and AB. The frequency of AA was low in IPF. The cross‐reaction of RF with avian antigens was excluded, and no reactivity against human IgG by AA was detected. Other endogenous interferences were ruled out.

Conclusion No single immunological test may definitively distinguish pigeon HP from AB and other interstitial lung disorders; however, positive RF, together with high AA levels, seems to be useful in differentiating the diagnosis.
Effect of various stabilizing agents on Imperata cylindrica grass pollen allergen extract
Authors: Bijli K. M. , Singh B. P. , Sridhara S. , Gaur S. N. , Arora N.
Published: March 2003

Background Allergen extracts are unstable, heat labile or susceptible to proteases. Stability of allergen extracts is important for proper diagnosis and therapy of allergic disorders.

Objective The present study was undertaken to determine the preservation and stabilization conditions of Imperata cylindrica (Ic) grass pollen extract.

Methods The Ic extract was kept with 0.1 mε‐aminocaproic acid (EACA), 0.75 m sucrose, 5% glycerol, 0.03% human serum albumin (HSA) or 0.4% phenol for different time periods. The extracts were stored for 3, 6 and 12 months each at 4 °C, 4 °C with daily exposure to room temperature (RT) for 1 h, and RT. The quality of extracts was analysed by SDS‐PAGE, Western blot, ELISA, ELISA inhibition and skin test.

Results Extracts kept with EACA and sucrose retained most of the protein bands followed by glycerol as determined by SDS‐PAGE and Western blot during all storage periods and conditions in comparison with standard extracts. The extracts kept with HSA, phenol and without preservative (WP) showed protein degradation below 33 kDa after 3 months storage at all conditions. However, a 67‐kDa allergen was stable in these extracts. EACA extract required 75 to 120 ng of protein for 50% inhibition in IgE binding under different conditions, whereas standard extract required 70 ng for the same. ELISA also demonstrated high allergenic reactivity of EACA extract. ID test on allergy patients with EACA extract demonstrated same allergenic potency as that of standard extract.

Conclusion EACA is the best preservative/stabilizing agent of Ic pollen extract, followed by sucrose and glycerol. Ic extract kept with phenol, HSA and without preservative showed degradation within 3 months. EACA preserved extract is equally potent as that of standard extract up to 1 year's storage.
Allergen‐specific conventional immunotherapy decreases immunoglobulin E‐mediated basophil histamine releasability
Authors: Shim J.‐Y. , Kim B.‐S. , Cho S.‐H. , Min K.‐U. , Hong S.‐J.
Published: March 2003

Background Allergen‐specific immunotherapy has proven to be clinically effective in the treatment of patients with atopic asthma; however, the mechanisms are still unclear. Several noted immunological changes include an increase of the allergen‐specific IgG antibody, a reduction in the allergen‐specific IgE antibody subsequent to transient increase, an allergen‐specific T cell shift in cytokine production from Th2 to Th1, and a decrease in quantity and activity of basophils and mast cells.

Objective To analyse the changes of basophil histamine release in response to IgE‐mediated and non‐IgE‐mediated stimuli before and after conventional house‐dust mite immunotherapy in children who suffer from atopic asthma.

Methods Fourteen Dermatophagoides farinae (Df) sensitive asthmatic children with conventional immunotherapy were examined. Basophil histamine releasability was measured 0 months (just before immunotherapy), 4 months and 9 months after immunotherapy. Basophils were stimulated with Df and goat anti‐human IgE antibody as IgE‐mediated stimuli; and formyl‐Met‐Leu‐Phe (fMLP) and calcium ionophore A23187 as non‐IgE‐mediated stimuli. Accordingly, the asthma symptom score was used to assess clinical outcome and the skin test reactivity to Df was measured.

Results In contrast to pre‐immunotherapy activity, 4 and 9 months after immunotherapy there were significant decreases in histamine release by Df and by anti‐IgE antibody. The histamine release by fMLP and by calcium ionophore showed no significant changes after immunotherapy. Histamine release by Df demonstrated significant correlation to that by anti‐IgE antibody and by fMLP, yet there was no observable correlation between histamine release by Df and by calcium ionophore. The asthma symptom score decreased significantly 4 and 9 months after immunotherapy and showed significant correlation with histamine release by Df. The skin test reactivity (allergen/histamine ratio) remained constant 4 months after immunotherapy, but decreased significantly 9 months after immunotherapy.

Conclusion Basophils have the potential to play an important role in the early clinical improvement of conventional immunotherapy in children with atopic asthma, which may be a result of the decreased IgE‐mediated histamine releasability during immunotherapy.
Local release of eosinophil peroxidase following segmental allergen provocation in asthma
Authors: Erpenbeck V. J. , Hohlfeld J. M. , Petschallies J. , Eklund E. , Peterson C. G. B. , Fabel H. , Krug N.
Published: March 2003

Background Eosinophil peroxidase (EPO) is an eosinophilic basic protein, which leads to increased permeability and damage of bronchial epithelial cells in asthma.

Objective As little is known about its local expression and release in humans the intracellular expression in lung and peripheral eosinophils and the concentrations of EPO in bronchoalveolar lavage (BAL) fluid and serum was investigated in patients with asthma.

Methods Twelve mild atopic asthmatic and nine control subjects underwent segmental sham and allergen challenge. EPO concentrations in BAL fluid and serum were determined by immunoassay and flow cytometry was used to determine the intracellular expression of EPO in BAL‐derived and peripheral eosinophils.

Results In asthmatic patients a large increase in BAL eosinophils – total cells: median 9.5 × 106 (range: 0.5 to 455.0 × 106); relative: 38% (1 to 91%) – was detectable 24 h following allergen challenge, but peripheral blood eosinophil counts did not change. Concentrations of EPO in BAL fluid increased from 1 µg/L (1.0 to 6.8 µg/L) to 42 µg/L (5.6 to 379.6 µg/L; P < 0.01) after allergen but not after saline challenge (1.5 µg/L; 1.0 to 21.9 µg/L), whereas in control subjects all measurements were below the detection limit. Serum concentrations of EPO increased slightly from 18.3 µg/L (3.0 to 56.8 µg/L) to 27 µg/L (3.8 to 133.9 µg/L; P < 0.05) 24 h after allergen challenge in asthmatic patients. Furthermore, the intracellular expression of EPO (measured as mean fluorescence intensity) was decreased in BAL eosinophils compared with blood eosinophils (mean fluorescence intensity 29 (7 to 71) vs. 48 (20 to 85); P < 0.01) after allergen challenge.

Conclusion The finding of increased EPO concentrations in the BAL fluid and decreased intracellular EPO expression in pulmonary eosinophils of asthmatic patients reflects the allergen‐triggered release of EPO into the bronchial space.
Extended freeze‐dried Mycobacterium bovis Bacillus Calmette–Guérin induces the release of interleukin‐12 but not tumour necrosis factor‐α by alveolar macrophages, both in vitro and in vivo
Authors: Hubeau C. , Singer M. , Lagranderie M. , Marchal G. , Vargaftig B.
Published: March 2003

Background Airway hyper‐responsiveness (AHR), chronic airway inflammation and predominance of the T helper type‐2 (Th2; IL‐4, IL‐5, IL‐13) over the Th1 (IL‐2, IFN‐γ) immune response are hallmarks of asthma. Alveolar macrophages (AM) are the most numerous cells in the airway lumen, where they represent the first immune cell population encountered by inhaled antigens. AM act as antigen‐presenting cells (APC) and they release various soluble mediators and enzymes. AM thus play a prominent role in the modulation of the local immunity in airways. In allergic airways, AM have been implicated in the pathogenesis of inflammation by promoting the Th2 versus the Th1 cytokine patterns.

Objectives Infections with attenuated bacteria or challenges with bacterial products may involve AM. Such stimuli have been shown to potentially restore the Th1/Th2 balance in asthmatic airways, but they also induce the release of inflammatory mediators. We investigated the response of AM when stimulated by two preparations of non‐proliferating Bacillus Calmette–Guérin (BCG).

Methods We evaluated the cytokine production by AM from BP2 and C57BL/6 mice when cultured with heat‐killed (HK) and extended freeze‐dried (EFD) BCG. We then investigated in vivo the release of soluble factors in the airway lumen of mice after instillation of these BCG preparations. Finally, we studied the profile of cytokine transcripts in the lung of mice pre‐treated with BCG and then challenged with ovalbumin (OVA).

Results HK BCG induced the production of both TNF‐α and IL‐12, and did not prevent high levels of Th2 cytokine transcripts. In contrast, EFD BCG induced a response dominated by the production of IL‐12, with no later over‐expression of Th2 cytokine transcripts.

Conclusion Our results show that EFD BCG induce the release of the Th1‐promoting cytokine IL‐12 by AM, without the deleterious effects of HK BCG. These data suggest that EFD BCG may be considered as a potential novel treatment to restore the Th1/Th2 imbalance in asthma.
Neonatal eosinophilic pustular folliculitis
Authors: Buckley D. A. , Munn S. E. , Higgins E. M.
Published: March 2003

Eosinophilic pustular folliculitis (EPF) of infancy is a rare disorder which may begin in the neonatal period and cause considerable parental anxiety. It must be distinguished from other causes of a pustular eruption in neonates, including infection and erythema toxicum neonatorum, and rare disorders such as transient neonatal pustular melanosis, infantile acropustulosis and Langerhans' cell histiocytosis. Skin smears and occasionally skin biopsy may be necessary to reach a diagnosis. We report a case of a Caucasian child with an unusually early onset of EPF in the first day of life. We wish to emphasize the importance of recognizing this self-limiting condition in order to prevent inappropriate antimicrobial treatment.
Lipoatrophy semicircularis induced by trauma
Authors: Gruber P. C. , Fuller L. C.
Published: March 2003

Lipoatrophy semicircularis is thought to be a rare condition characterized by band-like horizontal depressions of the skin typically involving the lower limbs. Previous literature has suggested that repetitive trauma to the lower limbs could explain this condition; however, no direct causal link has ever been clearly established. There have also been several reports where no preceding history of trauma could be found. In our series we report seven cases of lipoatrophy semicircularis representing over one-third of the staff in a particular office. We propose that the most logical explanation for the indentations present in these individuals is repetitive trauma to their thighs by the sharp edge of the desks. The consistent nature of the distance between the floor and the horizontal indentations on the lower limbs despite differences in height weight and body mass index support this theory. It is likely that this condition is more common than initially thought.
Terbinafine treatment of Trichophyton equinum infection in a child
Authors: Amor E. , Gutiérrez M. J. , Lamoneda C. , Del Palacio A. , Pereiro M
Published: March 2003

A case of tinea faciae caused by Trichophyton equinum affecting a 5-year-old boy is described. The boy had ridden a pony a month earlier and responded to a 6-week course of treatment with oral and topical terbinafine.
Glucocorticoid inhibition of adjuvant arthritis synovial macrophage nitric oxide production: role of lipocortin 1
Authors: Yang Y H , Hutchinson P , Santos L L , Morand E F
Published: March 2003

Nitric oxide (NO) is a mediator of inflammatory injury which is inhibited by glucocorticoids and is implicated in rheumatoid (RA) and adjuvant arthritis (AA). The glucocorticoid-induced anti-inflammatory molecule lipocortin 1 is expressed in RA synovium, but the effects of lipocortin 1 on synovial inflammation have been little studied. We investigated the effects of glucocorticoids and lipocortin 1 on inducible NO synthase (iNOS) and glucocorticoids on the induction of lipocortin 1 in AA synovial macrophages. NO production was measured by Griess assay in supernatants of day 14 AA rat synovial explants and of synovial macrophages purified from enzyme-digested synovium and treated with lipopolysaccharide (LPS) 1 μg/ml, dexamethasone (DEX) 10−7 m, and anti-lipocortin 1 MoAb. iNOS and lipocortin 1 expression were detected by flow cytometry using specific MoAb. Cell surface lipocortin was determined by Western blot. NO was produced by all AA synovial explants and NO was released by cultured synovial macrophages (14.5 ± 2.1 μmol/24 h). iNOS was detected in synovial macrophages (ED-1+) by permeabilization flow cytometry. LPS increased synovial macrophage NO release (P < 0.0001) and iNOS expression (P = 0.04). DEX inhibited constitutive (P = 0.002) and LPS-induced (P < 0.001) NO release and iNOS expression (P = 0.03). DEX inhibition of synovial macrophage NO was associated with induction of cell surface and intracellular lipocortin 1. Anti-lipocortin 1 MoAb treatment reduced the inhibition of NO release by DEX (P = 0.002), but had no effect on iNOS expression. These findings demonstrate a role for lipocortin 1 in the inhibition by glucocorticoids of AA synovial macrophage iNOS activity.
Binding of gluten-derived peptides to the HLA-DQ2 (α1*0501, β1*0201) molecule, assessed in a cellular assay
Authors: Shidrawi R G , Parnell N D J , Ciclitira P J , Travers P , Evan G , Rosen-Bronson S
Published: March 2003

The nature of the immunopathogenic relationship underlying the very strong association of coeliac disease (CD) to the HLA-DQ (A1*0501, B1*0201) genotype is not known, but probably relates to binding of gluten-derived epitopes to the HLA-DQ (α1*0501, β1*0201) heterodimer (DQ2). These epitopes have not yet been defined. In this study we have tested the binding of various gluten-derived peptides to DQ2 in a cellular assay using Epstein–Barr virus (EBV)-transformed B lymphocytes and murine fibroblast transfectants. One of these peptides (peptide A), which has previously been shown to exacerbate the CD lesion in vitro and in vivo, was found to bind to DQ2, albeit only moderately, lending further credence to its possible role in the pathogenesis of CD. The nature of peptide A's binding to DQ2 was explored with truncated and conservative point substituted analogues and compared with the published DQ2 binding motif, the results of which explain the observed level of binding.
Characterization of porcine CD5 and CD5+ B cells
Authors: Appleyard G D , Wilkie B N
Published: March 2003

Evidence strongly supports a role for the lymphocyte transmembrane glycoprotein CD5 in intracellular signalling events, whereby antigen-dependent growth and differentiation signals are augmented. Apart from its role in activation-related signalling, CD5 has been regarded as a possible B cell lineage marker differentiating subsets, CD5+ B cells (also termed B1 cells) and conventional B cells (or B2 cells). To extend these investigations to the study of pigs, porcine B cells were examined for evidence of CD5 expression. The influence of cellular activation on CD5 expression and CD5's role in signal transduction events and lymphocyte proliferation were examined. Using an anti-porcine CD5 MoAb (b53b7), porcine B cells were shown to be heterogeneous for CD5 expression. As in other species, B lymphocyte CD5 expression is low (dull), while IgM is high (bright). Ten to 30% of pig blood B lymphocytes are CD5+, with the highest frequency in neonates. Anti-CD5 antibody treatment was sufficient to induce rapid but transient calcium ion flux in porcine peripheral blood lymphocytes (PBL). CD5 expression increased on PBL following treatment with phorbol myristate acetate (PMA), lipopolysaccharide (LPS), or immobilized anti-IgM. LPS, PMA, and concanavalin A (Con A) but not anti-CD5, anti-IgM, or combinations of these antibodies induced lymphocyte 3H-thymidine uptake. CD5+ B cells are a common constituent of porcine circulating lymphocytes and resemble B1 cells of mice, man and other species in CD5 expression, frequency and lymphoid organ distribution. Porcine CD5, like CD5 in other species, mediates signal transduction, leading to changes in intracellular calcium concentration, but this signal alone is insufficient to promote cell division. A subset of porcine B cells up-regulates CD5 expression following phorbol ester activation.
Improvement of the lymphoproliferative immune response and apoptosis inhibition upon in vitro treatment with zinc of peripheral blood mononuclear cells (PBMC) from HIV+ individuals
Authors: Neves I , Bertho A L , Veloso V G , Nascimento D V , Campos-Mello D L A , Morgado M G
Published: March 2003

Clinical improvement has been described in AIDS patients submitted to zinc therapy, but the mechanisms involved are not well understood. In order to evaluate the effect of the zinc ions in the enhancement of the immune response, we tested its role in the lymphoproliferative response to a mitogen, as well as in the prevention of apoptosis. The mitogenic effect of zinc (10−4 m ZnCl2) on the lymphocyte proliferative response was observed in healthy controls as well as in HIV-1+ asymptomatic individuals. Very low stimulation index could be observed in AIDS patients (CD4+ < 200/mm3). However, zinc treatment of phytohaemagglutinin (PHA; 5 μg/ml)-stimulated PBMC cultures significantly enhanced 3H-thymidine incorporation in both asymptomatic and symptomatic groups. A decreased percentage of apoptotic cells could be identified in cell cultures from HIV-1+ individuals submitted to zinc treatment compared with cells treated only with PHA, as detected by both flow cytometry and agarose gel electrophoresis. Further studies with zinc supplementation associated to anti-retroviral therapy would be of great interest to evaluate the in vivo role of this oligoelement in the improvement of the immunological functions of HIV-1-infected individuals and AIDS patients.
Increased IL-10 production by stimulated whole blood cultures in primary IgA nephropathy
Authors: De Fijter J W , Daha M R , Schroeijers W E M , Van ES L A , Van Kooten C
Published: March 2003

Most patients with primary IgA nephropathy (IgAN) have a significantly higher memory repertoire of IgA1-producing B lymphocytes in their bone marrow together with high plasma levels of IgA1. The connection between the mucosal immune system and the bone marrow compartment is probably based on traffic of either antigen-presenting cells (APC) or antigen-specific lymphocytes. Cytokines play an important role in the proliferation and differentiation of lymphoid cells. In order to mimic the in vivo situation as much as possible, we assessed cytokine production profiles ex vivo in 23 IgAN patients and matched controls, using lipopolysaccharide (LPS)- or phytohaemagglutinin (PHA)-stimulated whole blood (WB) cultures. Interferon-gamma (IFN-γ), IL-2, IL-6, IL-10 and tumour necrosis factor-alpha (TNF-α) production in culture supernatants were determined by cytokine-specific ELISAs. Compared with controls, PHA-stimulated cultures resulted in significantly higher IL-10 (P < 0.001), IL-2 (P < 0.005) and IFN-γ (P < 0.001) levels in IgAN patients, but no significant differences in TNF-α or IL-6 levels were found. In LPS-stimulated cultures, the only significant difference (P < 0.001) between the two groups was the increased IL-10 production in IgAN patients. The enhanced cytokine production in stimulated WB cultures suggests altered monocyte-related T cell responses in patients with IgAN. Increased IL-10 production may eventually result in an increased number of IgA-producing B lymphocytes in the bone marrow. In addition, high levels of endogenous IL-10 may down-regulate the effector functions of monocytes, or possibly APC in general, and consequently the IgA response at the mucosal level.
Kinetics of purified protein derivative (PPD) proliferation reflects underlying suppressor mechanisms revealed by limiting dilution analysis (LDA) in patients with extrapulmonary tuberculosis (TB)
Authors: Lukey P T , Latouf S E , Ress S R
Published: March 2003

Mononuclear leucocytes from the blood (PBML) and effusion (EML) of patients undergoing pericardiocentesis were assayed for proliferative response to purified protein derivative of Mycobacterium tuberculosis (PPD). Of the 23 patients tested, 10 had culture-positive tuberculous effusions, while 13 had non-tuberculous aetiologies. Three different kinetic responses were identified: (i) accelerated responses (found in 70% of EML from patients with culture-positive tuberculous effusions); (ii) ‘flat’ responses (found in 10% of EML from patients with culture-positive tuberculous effusions); and (iii) normal kinetic responses. These differences in kinetic response may reflect underlying immune mechanisms important in the immunopathogenesis of TB. In order to address this possibility we performed LDA on a selection of patients with culture-positive extrapulmonary TB: three patients with accelerated responses, two with normal responses, and one with a ‘flat’ response. The results confirm the previously reported accumulation of PPD-specific responder cells in the effusion of patients with TB. Cell-mediated suppressor mechanisms (as shown by ‘V’-shaped LDA curves) were found in the blood of one patient and the effusion of another. In both cases ‘flat’ PPD-proliferative responses were observed. However, the LDA data also suggested the presence of in vivo mechanisms limiting the clonal burst size. Thus it appears that immune responses in extrapulmonary TB are influenced by an array of inhibitory mechanisms, modulation of which may influence the outcome of infection.
Enhanced prostaglandin E2 production by monocytes in atopic dermatitis (AD) is not accompanied by enhanced production of IL-6, IL-10 or IL-12
Authors: Snijders A , Van Der Pouw Kraan T C T M , Engel M , Wormmeester J , Widjaja P , Zonneveld I M , Bos J D , Kapsenberg M L
Published: March 2003

AD is associated with a bias of the T helper cells to show increased IL-4 and reduced interferon-gamma (IFN-γ) production. The production of IFN-γ and IL-4 and the development of Th cells into either high IFN-γ or high IL-4 producers is strongly influenced by factors produced by antigen-presenting cells (APC), like IL-12 and prostaglandin E2 (PGE2). IL-12 selectively enhances IFN-γ production and favours the development of IFN-γ-producing Th cells, whereas PGE2 selectively inhibits IFN-γ production by Th cells. The aim of this study was to test whether the increased IL-4/IFN-γ production ratio by Th cells in AD can be explained by an increased PGE2/IL-12 production ratio by the APC. Monocytes were used as APC source. PGE2 and IL-12 production by lipopolysaccharide (LPS)-stimulated monocytes from 12 AD patients and 12 non-atopic controls was determined using two complementary experimental systems, whole blood cultures and purified monocytes. In addition, we determined IL-6 production as a measure of monocyte activation, and IL-10 production because IL-12 production by monocytes is highly influenced by endogenously produced IL-10. The monocytes from AD patients showed normal production levels of IL-6 and IL-10, a two-fold, but non-significant decrease in IL-12 production, and a significantly (three-fold) higher PGE2 production than those from non-atopic controls. Here we show for the first time that enhanced PGE2 production by monocytes in AD is not accompanied by a general rise in cytokine production. We conclude that AD is indeed associated with an increased PGE2/IL-12 production ratio by monocytes.
cDNA cloning of a novel autoantigen targeted by a minor subset of anti-centromere antibodies
Authors: Muro Y , Yamada T , Himeno M , Sugimoto K
Published: March 2003

Using autoimmune serum from a patient with anti-centromere antibodies, we have identified and partially characterized a novel protein with a mol. wt of ≈ 27 kD (hereafter referred to as p27). A cDNA expression library was screened with this serum, and two overlapping inserts were isolated among three positive clones other than clones corresponding to centromere protein (CENP)-B and CENP-C. Analysis of the sequence showed an open reading frame of ≈ 0.6 kb encoding 199 amino acids with a predicted mol. wt of 21.5 kD. Immunoblotting analysis with bacterial recombinant p27 showed that ≈ 2% of anti-centromere antibody-positive patients had autoantibodies to p27, whereas only one of 215 autoimmune patients without anti-centromere antibodies reacted with the recombinant. All five cases with anti-p27 antibodies, who were diagnosed as having scleroderma and/or Sjögren's syndrome, showed internal organ involvement. Although affinity-purified anti-p27 human or mouse polyclonal antibodies failed to stain any cellular structures in an immunofluorescence study, the potential association of anti-p27 with anti-centromere antibodies suggests that this novel autoantigen might play a role in mitosis.
Circulating T lymphocyte subsets in coeliac disease (CoD) patients and healthy family members
Authors: Kerttula T O , Holm K , Partanen J , Polvi A , Mäki M
Published: March 2003

Increased proportions of circulating antigen-primed CD45RO+ TCR γδ cells have been found in untreated CoD patients. As certain immunological features are now found in both CoD and healthy persons carrying the HLA DQ2 heterodimer, we sought to establish whether healthy members of the families of CoD patients who are positive for HLA DQ2 and also have increased densities of TCR γδ intraepithelial lymphocytes (IEL) in their small bowel mucosa have elevated levels of circulating TCR γδ memory cells. Peripheral blood T cells were analysed by flow cytometry in 22 patients with CoD and 16 healthy family members. Untreated CoD patients had higher percentages of circulating CD45RO+ TCR γδ cells and CD45RO+ Vδ1+ cells than healthy family members. On the other hand, the amount of circulating Vδ1+ lymphocytes was lower in patients with CoD compared with healthy family members. In contrast, no differences were found between HLA DQ2+ and HLA DQ2− healthy family members in respect of circulating TCR γδ cell subsets. The change in circulating TCR γδ cell subsets found in patients with CoD is thus a consequence of an ongoing immunological process which diminishes on a gluten-free diet rather than a phenomenon directly caused by DQ2. These changes in peripheral blood are not found in healthy individuals who have the same HLA alleles DQA1*0501 and DQB1*0201 encoding the HLA DQ2 and who also have increased densities of TCR γδ IEL in their otherwise normal jejunal mucosa.
Abnormal T cell responses to bacterial superantigens in Behçet's disease (BD)
Authors: Hirohata S , Hashimoto T
Published: March 2003

This study examines the nature of T cell hypersensitivity in BD. Highly purified T cells from 32 BD patients, from 29 rheumatoid arthritis (RA) patients and from 14 healthy individuals were cultured with various concentrations of Staphylococcal enterotoxins (SE) B and C1 in the presence of monocytes for 5 days, after which the production of interferon-gamma (IFN-γ) was assessed. High concentrations of SE (1 ng/ml) stimulated BD T cells as well as control T cells to produce comparably high amounts of IFN-γ, whereas low concentrations of SE (1 pg/ml) stimulated BD T cells much more effectively than normal or RA T cells. The hypersensitivity of BD T cells to low concentrations of SEC1 was restored with RA monocytes instead of BD monocytes, whereas BD monocytes could not elicit the SEC1-induced IFN-γ production of RA T cells. Moreover, there were no significant differences between BD T cells and RA T cells in monocyte-independent IFN-γ production stimulated with low or high concentrations of immobilized anti-CD3, or in the monocyte-mediated enhancement of IFN-γ production stimulated with a low concentration of immobilized anti-CD3. These results confirm that T cell hypersensitivity is not confined to certain specific antigens in BD. More importantly, the data strongly suggest that abnormalities in signal transduction triggered by perturbation of T cell receptors, but not in that induced by cross-linking of CD3 molecules nor in that delivered through costimulation molecules, play an important role in the pathogenesis of BD.
Autoantibody prevalence in children with liver disease due to chronic hepatitis C virus (HCV) infection
Authors: Gregorio G V , Pensati P , Iorio R , Vegnente A , Mieli-Vergani G , Vergani D
Published: March 2003

HCV infection and interferon-alpha (IFN-α) therapy have been associated with autoimmunity. To assess whether chronic liver disease (CLD) due to HCV infection or its treatment with IFN-α cause autoimmune manifestations, the prevalence of tissue autoantibodies in 51 children with chronic HCV infection and 84 with other CLD was analysed by standard techniques. Sixty-five percent of patients with chronic HCV infection, 66% with chronic hepatitis B infection and 60% with Wilson's disease were positive for at least one autoantibody. In the 51 subjects with chronic HCV infection (29 treated with IFN-α, 22 untreated), tested on 165 occasions over a median of 9 months (range 5–42 months), autoantibodies to nuclei (ANA), smooth muscle (SMA), gastric parietal cell (GPC) and/or liver kidney microsomal type 1 (LKM-1) were similarly prevalent in treated and untreated patients (90% versus 68%, P = 0.12). Positivity for SMA was present in 67%, GPC in 32%, ANA in 10%, LKM-1 in 8% of cases. Treatment with IFN-α had to be suspended due to transaminase elevation in one SMA-positive, one ANA-positive but in three of four LKM-1-positive patients. Our results show that: (i) autoantibodies are common in viral-induced hepatitis and Wilson's disease; (ii) positivity for SMA, GPC, ANA is part of the natural course of chronic HCV infection, their prevalence being unaffected by IFN-α; and (iii) IFN-α should be used cautiously in the treatment of LKM-1/HCV-positive patients.
Increase in dendritic cell numbers, their function and the proportion uninfected during AZT therapy
Authors: Gompels M , Patterson S , Roberts M S , Macatonia S E , Pinching A J , Knight S C
Published: March 2003

The effects of AZT treatment on the numbers, level of infection and function of peripheral blood dendritic cells (DC) were examined in patients with HIV infection. This was a cross-sectional study of patients before AZT treatment and up to 20 months after initiation of treatment. Numbers of DC separated by density gradients were below the normal range in patients before treatment, but increased between 3 and 12 months of treatment. The numbers of DC per provirus copy rose from around 100 cells to 5000 cells and this decrease in viral load in DC was significant between 3 and 20 months of treatment. The capacity of DC to stimulate allogeneic T cell proliferation was low before treatment and significantly higher between 6 and 12 months after the start of AZT. This study indicated that AZT treatment produced beneficial effects on DC by increasing their numbers, reducing the provirus load and increasing their function in stimulating T cells. These results support the thesis that the function of these potent antigen-presenting cells is important in development of immunological defects in AIDS, and that effects of AZT treatment on DC may provide a measure of its therapeutic effect.
Phenotypic and functional modulation of T cellsin vivoby extrathymic T cells when T cells with MHC class II disparity were injected into athymic nude mice
Authors: Tomiyama K , Watanabe H , Seki S , Ito M , Abo T
Published: March 2003

TCRhigh cells are generated by the mainstream of T cell differentiation in the thymus, whereas TCRint cells (or NK1.1+ T cells) are generated extrathymically in the liver and by an alternative intrathymic pathway. It is still unknown how these T cell populations interact in vivo with each other. To investigate the interaction of TCRint cells with TCRhigh cells, we used congenitally athymic nude (B6-nu/nu) mice which carry only TCRint cells in all immune organs. When TCRhigh cells from B6-C-H-2bm12 (bm12) mice (i.e. I-Abm12) were injected into B6-nu/nu mice (i.e. 1-Ab), the expanding T cell population was a mixture of TCRhigh cells of donor origin and TCRint cells of recipient origin. However, 9 Gy-irradiated nude mice permitted a full expansion of TCRhigh cells which expressed the IL-2Rα+β+ phenotype, namely, they were at the most activated state. These mice died of acute graft-versus-host disease (GVHD) within 5 days. On the other hand, non-irradiated nude mice suppressed the expansion of TCRhigh cells of donor origin and such TCRhigh cells continued to have the IL-2Rα±β+ phenotype. These mice could survive but showed signs of chronic GVHD thereafter. In both situations, CD4+αβ T cells expanded irrespective of donor or recipient origin. These results suggest that TCRint cells in the recipient mice possess a regulatory function in relation to donor TCRhigh cells; as a result, fully activated TCRhigh cells acquired the IL-2Rα+β+ phenotype and injured the host, but TCRhigh cells suppressed in vivo remained as the IL-2Rα±β+ phenotype and only partially injured the host.
Effects of IL-2 therapy in asymptomatic HIV-infected individuals on proliferative responses to mitogens, recall antigens and HIV-related antigens
Authors: Kelleher A D , Roggensack M , Emery S , Carr A , French M A , Cooper D A
Published: March 2003

The effects of IL-2 therapy on lymphoproliferative responses to mitogens, recall antigens and HIV epitopes were studied in asymptomatic HIV-infected patients enrolled in a phase II study of intermittent continuous intravenous (CIV) IL-2 and subcutaneous infusions of polyethylene glycol-modified (PEG) IL-2. Sixteen consecutive patients randomized to receive CIV IL-2 (n = 5), PEG IL-2 (n = 7) or anti-viral therapy alone (n = 4) were studied. All patients were vaccinated with tetanus toxoid (TT) before receiving therapy. Proliferative responses to phytohaemagglutinin (PHA), soluble anti-CD3, TT, streptokinase/streptodornase (SK/SD) and 11 previously described HIV-specific T-helper epitopes from gag and env were studied at weeks 0, 16, 30 and 48. Median CD4+ lymphocyte increases of 272 and 255 CD4+ cells/μl were observed in the CIV IL-2 and PEG IL-2 groups at week 48, while decreasing by 104 cells/μl in the anti-retroviral therapy alone group. At each time point proliferative responses to PHA, anti-CD3, TT and SK/SD were not different between treatment arms. Similarly, no differences in responses to HIV epitopes were found between the groups and no new responses to HIV epitopes were detected. IL-2 therapy results in a significant increase in peripheral blood CD4+ lymphocyte count, but this increase is not associated with quantifiable improvements in lymphoproliferative responses to mitogens, recall or HIV antigens.
Iodination of human thyroglobulin (Tg) alters its immunoreactivity. II. Fine specificity of a monoclonal antibody that recognizes iodinated Tg
Authors: Saboori A M , Rose N R , Burek C L
Published: March 2003

In a previous investigation, we found that murine MoAb 42C3, raised against human Tg, recognized Tg differently depending upon its level of iodination of Tg. A possible explanation for this finding is that iodine is directly involved with the specific epitope recognized by MoAb 42C3. In the present study, we report that the binding of MoAb 42C3 to iodinated Tg is inhibited by T4, T3, reverse T3 (rT3), triiodothyroacetic acid (triac), diiodothyronine (T2), diiodotyrosine (DIT), but not by thyronine (T0) or tyrosine. The order of inhibition of these iodinated compounds is T4 > T3 > rT3 > triac > T2 > DIT. The MoAb 42C3 does not have the same specificity as the T3, T4-receptor since the order of binding of these iodinated compounds on the receptor differed from the order of their inhibition of this MoAb. Monoclonal antibody 42C3 also recognized non-iodinated Tg that was subsequently iodinated in vitro. It failed to recognize another protein, bovine serum albumin, that was iodinated in vitro by the same method. These results suggest that iodinated tyrosines and thyronines determine the binding specificity of MoAb 42C3. The inhibitory effects of these compounds on MoAb 42C3 depend on their iodine content as well as location of iodine in the aromatic ring.
The murine buccal mucosa is an inductive site for priming class I-restricted CD8+ effector T cellsin vivo
Authors: Desvignes C , Estèves F , Etchart N , Bella C , Czerkinsky C , Kaiserlian D
Published: March 2003

The present study shows that Langerhans cells of the buccal mucosa and the skin share a similar phenotype, including in situ expression of MHC class II, the mannose receptor DEC-205 and CD11c, and absence of the costimulatory molecules B7.1, B7.2 and CD40 as well as Fas. Application of 2,4-dinitrofluorobenzene (DNFB) onto the buccal mucosa is associated with a rapid migration of dendritic cells (DC) to the epithelium and induction of B7.2 expression on some DC. Buccal sensitization with DNFB elicited a specific contact sensitivity (CS) in response to skin challenge, mediated by class I-restricted CD8+ effector T cells and down-regulated by class II-restricted CD4+ T cells, demonstrated by the lack of priming of class I-deficient mice and the enhanced response of class II-deficient mice, respectively. CS induced by buccal immunization is associated with priming of class I-restricted CD8+ effector T cells endowed with hapten-specific cytotoxic activity. Thus, the buccal epithelium is an inductive site, equivalent to the epidermis, for the generation of CS independent of CD4 help, and of cytotoxic T lymphocyte (CTL) responses mediated by class I-restricted CD8+ T cells. We propose that immunization through the buccal mucosa, which allows antigen presentation by epithelial DC efficient for priming systemic class I-restricted CD8+ CTL, may be a valuable approach for single-dose mucosal vaccination with subunit vaccines.
Autoimmune responses to the β cell autoantigen, insulin, and the INS VNTR-IDDM2 locus
Authors: Sarugeri E , Dozio N , Belloni C , Meschi F , Pastore M R , Bonifacio E
Published: March 2003

Type 1 diabetes is associated with autoimmunity to insulin. Genetic susceptibility to type 1 diabetes is polygenic and includes the INS VNTR-IDDM2 locus which may regulate the expression of insulin in pancreas and thymus. In order to determine whether insulin autoimmunity could be attributed to a genetic susceptibility conferred by the INS VNTR-IDDM2 locus, peripheral blood T cell proliferation to human insulin and insulin autoantibodies (IAA) was measured in patients with new onset type 1 diabetes and control subjects. IAA were detected in 21 of 53 patients and in none of 25 control subjects, while T cell responses were low (stimulation index range 0.4–7.2) and similar in both groups. Both antibody and T cell responses were higher in younger subjects and IAA were more prevalent in patients with the HLA-DR4 allele. No relationship was observed between humoral and cellular responses to insulin. No association was found between the INS VNTR-IDDM2-susceptible allele and insulin autoimmunity. Increased T cell responses and IAA were found in patients with either the diabetes-susceptible or the diabetes-protective INS VNTR-IDDM2 locus genotypes, and increased T cell responses were also found in control subjects with either susceptible or protective INS VNTR-IDDM2 locus genotypes. This study confirms that primary T cell proliferative responses to insulin are low and detectable also in control subjects. The detection of T cell proliferation and autoantibodies to insulin in subjects with and without the protective INS VNTR-IDDM2 locus genotypes does not support the hypothesis of an allele-specific capacity for tolerance induction which could determine a susceptibility to develop autoimmunity against the insulin protein and subsequently diabetes.
Existence of activated and memory CD4+ T cells in peripheral blood and their skin infiltration in CD8 deficiency
Authors: KATAMURA K , TAI G , TACHIBANA T , YAMABE H , OHMORI K , MAYUMI M , MATSUDA S , KOYASU S , FURUSHO K
Published: March 2003

CD8 deficiency is a rare primary immunodeficiency caused by the defect of a tyrosine kinase, ZAP-70, which transduces signals from the T cell receptor. We report here a case of CD8 deficiency, having CD4+ T cells with a unique phenotype. The patient's T cells did not respond to anti-CD3 stimulation in vitro, suggesting that they were naive. However, many CD4+ T cells with activated and memory phenotypes, which expressed CD45RO+, HLA-DR+ and CD25+, were present in the peripheral blood, and these cells accumulated in the perivascular area of his infiltrative erythematous skin lesions. The patient's T cells could be activated by a high concentration of phytohaemagglutinin (PHA), indicating the presence of an alternate signalling pathway which bypasses ZAP-70 and activates CD4+ T cells in vivo. The origin and role of activated CD4+ T cells in the pathogenesis involved in the skin lesions are discussed.
Human Th1 responses driven by IL-12 are associated with enhanced expression of CD40 ligand
Authors: HIROHATA S
Published: March 2003

IL- 12 is the prominent inducer of Th1 responses in humans and in the mouse. CD40 ligand (CD40L) plays important roles in regulation of immune responses, including T cell-dependent activation of B cells and cytokine production by monocytes and dendritic cells. The present study examined the influences of IL-12 on the CD40L expression of activated human CD4+ T cells. IL-12 enhanced CD40L expression on CD4+ T cells stimulated with immobilized anti-CD3 in the complete absence of accessory cells, whereas IL-4 and IL-10 decreased it. Exogenous interferon-gamma (IFN-γ) did not increase CD40L expression on immobilized anti-CD3 stimulated CD4+ T cells at any time up to 168 h of culture. The IL-12-induced enhancement of CD40L expression on anti-CD3 activated CD4+ T cells was not influenced in the presence of a metalloproteinase inhibitor KB8301, which up-regulated CD40L expression by preventing the processing of membrane-bound CD40L, or B cells, which down-regulated CD40L expression by receptor-mediated endocytosis. These results indicate that IL-12 enhances the CD40L expression of activated CD4+ T cells independently of the IFN-γ production. The data thus suggest that Th1 responses induced by IL-12 might play an important role in the regulation of humoral immune responses through up-regulated CD40L expression.
Monocyte activation in rheumatoid arthritis (RA): increased integrin, Fcγ and complement receptor expression and the effect of glucocorticoids
Authors: TORSTEINSDÓTTIR I , ARVIDSON N G , HÄLLGREN R , HÅKANSSON L
Published: March 2003

The aim of this work was to study the expression of β1- and β2-integrins, CR1, CD44 and Fcγ receptors on peripheral blood monocytes in RA. The expression of these receptors was measured by flow cytometry, before and after treatment with low-dose prednisolone. Expression of the same receptors was also measured before and after treatment with metyrapone, a substance that inhibits the synthesis of cortisol in the adrenals. The expression of the β2-integrins CD11a, CD11b and CD18, of CD35 (CR1), and of FcγRII and FcγRI (CD32 and CD64) on monocytes was elevated in the RA patients compared with healthy controls, while the expression of the β1-integrins (CD29, CD49d, CD49f) was unaffected. A significant correlation between monocyte expression of CD64 and C-reactive protein (CRP), and blood platelet count, respectively, was found in the group of patients with RA. After 4–6 weeks of treatment with low-dose prednisolone, the expression on the monocytes of CD11a, CD11b, CD18, CD35, CD32 and CD64 was normalized. A significant correlation (r = 0.64, P = 0.02) was found between the decrease in expression of CD11b and clinical improvement after prednisolone treatment. Two days of metyrapone treatment, which significantly lowered the serum cortisol levels, elevated the expression of CD35 and CD49f. Priming of peripheral monocytes seems to be one of the mechanisms behind the recruitment of monocytes to the rheumatoid synovium. One reason for the good clinical effects of prednisolone in RA could be a down-regulation of adhesion and phagocytosis receptors on monocytes.
Candida albicanssuppresses nitric oxide (NO) production by interferon-gamma (IFN-γ) and lipopolysaccharide (LPS)-stimulated murine peritoneal macrophages
Authors: CHINEN T , QURESHI M H , KOGUCHI Y , KAWAKAMI K
Published: March 2003

We examined the in vitro effect of Candida albicans on NO production by macrophages. Candida albicans suppressed not only NO production but also expression of inducible NO synthase (iNOS) mRNA by murine IFN-γ and bacterial LPS-stimulated peritoneal macrophages. The suppression was not associated with inhibition but rather stimulation of IL-1β production. This effect was observed when more than 1 × 103/ml of Candida albicans were added to macrophage cultures (1 × 106 cells/ml) and reached a maximal level at 1 × 106/ml. The NO inhibitory effect of Candida albicans was mediated predominantly by as yet unidentified soluble factor(s) and to a lesser extent by direct contact. In addition, heat- or paraformaldehyde-killed Candida albicans did not show this inhibitory activity. Culture supernatant of Candida albicans also inhibited NO production by activated macrophages in a dose-dependent manner, and increased IL-1β production. Finally, the inhibitory effect was not mediated by IL-10 and transforming growth factor-beta (TGF-β), since neutralizing antibodies to these cytokines did not influence Candida albicans-induced reduction in macrophage NO production. Our results suggest that Candida albicans may evade host defence mechanism(s) through a soluble factor-mediated suppression of NO production by stimulated macrophages, and that the effect is independent of production of immunosuppressive cytokines such as IL-10 and TGF-β.