bluuebunny/crossref_metadata_2025 huggingface dataset:
Materno–fetal passage of nutritive and inhalant allergens across placentas of term and pre‐term deliveries perfused in vitro
Authors: Loibichler C. , Pichler J. , Gerstmayr M. , Bohle B. , Kiss H. , Urbanek R. , Szépfalusi Z.
Published: March 2003

Background The pre‐ and postnatal environment appears to be of crucial importance for the manifestation of allergic diseases, which often begin during infancy. Although T cell reactivity of fetal origin to a range of common allergens is present in most cord blood samples, the immunological basis remains unclear.

Objective In order to test the hypothesis of transplacental allergen transfer we studied double‐sided open ex vivo perfusion experiments of isolated placental cotyledons with the nutritive allergens beta‐lactoglobulin (BLG) and ovalbumin (OVA) and the inhalant major birch pollen allergen Bet v1.

Methods Placentas of full‐term and pre‐term newborns were obtained immediately after delivery to recover functionally active maternal and fetal circulations. Thus, a fetal artery and a fetal vein were cannulated and perfused with pure medium (fetoplacental circulation), whereas the intervillous space of placentas was flushed with allergen containing medium by puncture of the basal plate (maternoplacental circulation). Samples that were collected throughout the perfusion experiment from fetal venous outflow were tested by allergen‐specific enzyme‐linked immunosorbent assays (ELISA) for the presence of allergens indicative of materno–fetal transplacental passage.

Results We observed transplacental transfer of BLG, OVA and Bet v1 in placentas of term as well as premature deliveries. The respective allergen was readily detectable in fetal effluent at the beginning of the perfusion experiment and allergen levels reached a plateau after about 2 h. The steady state transfer rate of BLG and OVA in term placentas was 0.012% ± 0.001 and 0.013% ± 0.001 of total dose, i.e. 130.21 ± 7.41 ng/mL and 115.83 ± 6.07 ng/mL, respectively. The observed transfer rate of Bet v1 after 2 h of perfusion was 0.155% ± 0.034 of total dose, that is 2.41 ± 1.36 ng/mL. Transplacentally transferred concentration of BLG and OVA in pre‐term placentas increased continuously throughout perfusion time from 5.32 ± 0.92 ng/mL at 1 min to 87.53 ± 21.93 ng/mL at 120 min and 1.35 ± 0.31 ng/mL at 1 min to 112.87 ± 5.25 ng/mL at 150 min, respectively.

Conclusion Allergen‐specific cord blood reactivity may be attributed to low levels of allergens crossing the human placenta and providing the fetus with the necessary stimulus for T cell priming.
Allergens, Der p 1, Der f 1, Fel d 1 and Can f 1, in newly bought mattresses for infants
Authors: De Boer R.
Published: March 2003

Background To avoid allergen exposure of newborn babies, the use of a new mattress for the baby bed may be recommended. However, it is not certain that new mattresses are always free of allergens.

Objective In the present study the allergen content of new infant mattresses was investigated.

Methods Dust samples were vacuumed from 90 new mattresses for infant beds bought in 50 different Dutch shops, and the concentrations of Der p 1, Der f 1, Fel d 1 and Can f 1 were determined by radioimmunoassays.

Results Most mattresses contained some allergen and often the allergen concentrations were surprisingly high. Only 15 of the 90 mattresses contained no detectable amounts of any of the four allergens. The highest concentration found for each allergen was 3.1, 46.5, 20.2 and 95.7 µg/g of dust, respectively. However, the total amount of allergen in a mattress was still rather low because the new mattresses contained only modest amounts of dust. Baby mattresses more often contained an increased allergen load than the larger, standard‐sized, infant mattresses. This may be caused by differences in manufacturing procedure. Also, mattresses that were sold without a plastic encasement more often contained an increased allergen load.

Conclusions It is advisable to buy a mattress that is wrapped in plastic, but it may still contain a substantial amount of allergen. Thorough vacuuming of a newly bought mattress before it is installed on a child's bed, is also advisable. After instalment, regular vacuuming of the mattress and washing of the bed linen as well as measures to eliminate allergen reservoirs in other parts of the house are important, because our observations indicate that mattresses easily pick up allergens from the environment.
T cell cytokine responses to outer membrane proteins of Haemophilus influenzae and the house dust mite allergens Der p 1 in allergic and non‐allergic subjects
Authors: Epton M. J. , Hales B. J. , Thompson P. J. , Thomas W. R.
Published: March 2003

Background Haemophilus influenzae are ubiquitous colonizers of the nasopharynx, Little is known about the T cell cytokine responses to the antigens of these bacteria and whether or not the responses may interact with responses to aeroallergen.

Objective To measure the T cell cytokine responses to conserved outer membrane protein antigens of Haemophilus influenzae and to house dust mite allergen of subjects allergic to the house dust mite and of subjects without allergic sensitization.

Methods T cell responses were measured by in vitro proliferation and cytokine release from peripheral blood monocytes (PBMC). The allergen used was Der p 1 and outer membrane proteins were recombinant polypeptides representing the OMP6 and D15 antigens.

Results The PBMC of most subjects had proliferative responses to OMP6 and D15, which were highly correlated. The pattern of cytokine release was Th1 biased with high levels of IFN‐γ and usually little IL‐5 or IL‐13 although PBMC from a few subjects did release IL‐5 independent of allergic status. IL‐10 release was readily detected. There was no difference in the anti‐OMP cytokine response of PBMC from subjects without any known allergy and the responses of PBMC from subjects who were highly allergic to house dust mite. The responses to the Der p 1 allergen showed the expected Th2 cytokine release.

Conclusion The outer membrane protein antigens of the ubiquitous colonizing bacteria Haemophilus influenzae induce Th1 cytokine responses which are similar for PBMC from non‐allergic individuals and subjects with a high degree of allergy to the perennial house dust mite allergen and strong Th2 responses to Der p 1.
Phage‐displayed Bet mim 1, a mimotope of the major birch pollen allergen Bet v 1, induces B cell responses to the natural antigen using bystander T cell help
Authors: Schöll I. , Wiedermann U. , Förster‐Waldl E. , Ganglberger E. , Baier K. , Boltz‐Nitulescu G. , Scheiner O. , Ebner C. , Jensen‐Jarolim E.
Published: March 2003

Background and objective In previous studies we have generated mimotopes of Bet v 1, the major birch pollen allergen, by biopannings of phage‐display random peptide libraries. In the present study, we analysed the humoral and cellular immune response to Bet v 1‐mimotopes.

Methods The mimotope CFPYCYPSESA, designated Bet mim 1, was used for intraperitoneal immunizations of BALB/c mice in phage‐displayed form. For examination of the humoral immune response, enzyme‐linked immunosorbent assay (ELISA) experiments were applied. Stimulation capacities were investigated in cultured mouse splenocytes and in humoral Bet v 1‐specific T cell clones.

Results We demonstrated that the Bet mim 1‐induced murine antibody response against Bet v 1 was predominated by the IgG1 isotype. In these mice only the phage‐displayed mimotopes, but neither the allergen nor the synthetic Bet mim 1‐mimotopes were able to stimulate proliferation of cultured splenocytes. Using Bet v 1‐specific T cell clones of allergic patients, phage‐displayed and synthetic mimotopes were unable to stimulate T cell proliferation. Moreover, tolerance induction to Bet v 1 in mice by intranasal administration of Bet mim 1‐phages or Bet mim 1‐peptide failed.

Conclusion Taking these results together, our data indicate that Bet mim 1 mimics a Bet v 1‐epitope on the B cell but not on the T cell level. We suggest that the phage itself is responsible for the recruitment of T cells providing bystander help in the formation of a mimotope‐specific humoral response.
The relationship of alcohol consumption to total immunoglobulin E and the development of immunoglobulin E sensitization: the Copenhagen Allergy Study
Authors: Linneberg A. , Petersen J. , Nielsen N. H. , Madsen F. , Frølund L. , Dirksen A. , Jørgensen T.
Published: March 2003

Background Several studies in patient populations have reported a positive association between alcohol consumption and serum total IgE. Furthermore, we have previously reported a positive association between alcohol consumption and the prevalence of skin prick test (SPT positivity) to inhalant allergens in a population‐based cross‐sectional study.

Objective To investigate the relationship of alcohol consumption to levels of serum total IgE and the development of IgE sensitization to inhalant allergens.

Methods In 1990, self‐reported consumption of alcohol, serum total IgE, SPT positivity and specific IgE positivity to inhalant allergens were assessed in 1112 subjects, aged 15–69 years, participating in a population‐based cross‐sectional study in Copenhagen, Denmark. In 1998, they were invited to a follow‐up and 734 were re‐examined (participation rate 69.0%). Adjustment for potential confounders was performed by using multivariable regression analyses.

Results In non‐atopic (specific IgE negative) subjects there was a positive association between alcohol consumption and the concentration of total IgE (P = 0.001). During the follow‐up period, 45 and 33 subjects developed SPT positivity and specific IgE positivity, respectively. There was no significant association between alcohol consumption and the development of SPT positivity or specific IgE positivity. However, the risk of developing SPT positivity tended to increase with increasing consumption of alcohol (P = 0.055).

Conclusions This epidemiological study confirms that alcohol consumption has an influence on levels of serum total IgE. A significant association between alcohol consumption and the development of IgE sensitization was not established. However, there seems to be a lack epidemiological data on this issue.
Analysis of the sensitization profile towards allergens in central Africa
Authors: Westritschnig K. , Sibanda E. , Thomas W. , Auer H. , Aspöck H. , Pittner G. , Vrtala S. , Spitzauer S. , Kraft D. , Valenta R.
Published: March 2003

Background Almost no information is available regarding the prevalence of IgE‐mediated allergies and the disease‐eliciting allergens in tropical Africa.

Objective To study IgE‐mediated allergies and the allergen profile in allergic patients from Zimbabwe.

Methods The frequency of sensitization to common environmental allergen sources was determined by skin prick testing in 650 allergic patients from Zimbabwe. Fifty representative sera were analysed for IgE reactivity to 20 respiratory and 20 food allergen extracts by multiallergen extract testing. The IgE reactivity profiles to recombinant pollen and mite allergens were compared between grass pollen‐ and mite‐sensitized patients from Zimbabwe and central Europe. Sera from grass pollen‐allergic patients were also analysed for IgE reactivity to nitrocellulose‐blotted natural timothy grass and Bermuda grass pollen allergens.

Results IgE‐mediated allergies were found to be common in Zimbabwe. Similar to the situation in central Europe, mites and grass pollens represented the most prevalent allergen sources. However, the IgE reactivity profiles determined with single recombinant pollen and mite allergens revealed interesting differences between the European and African patients, which most likely reflect the local allergen exposure.

Conclusions The striking differences regarding sensitization to grass pollen and mite allergens between African and European patients revealed by recombinant allergen‐based testing emphasize the need for component‐resolved allergy testing to optimize allergy prevention and therapy in different populations.
Humoral and cellular responses to gliadin in wheat‐dependent, exercise‐induced anaphylaxis
Authors: Lehto M. , Palosuo K. , Varjonen E. , Majuri M.‐L. , Andersson U. , Reunala T. , Alenius H.
Published: March 2003

Background Wheat‐dependent, exercise‐induced anaphylaxis (WDEIA) is a severe allergy where wheat ingestion together with physical exercise induces anaphylaxis. We have previously shown that patients with WDEIA have IgE antibodies against gliadin proteins and identified ω‐5 gliadin (Tri a 19) as a major allergen.

Objective The aim of this study was to examine gliadin‐specific IgG subclass, IgA and IgE antibodies, basophil histamine release and cell‐mediated responses in WDEIA.

Methods Sera and peripheral blood mononuclear cells (PBMC) were obtained from patients with WDEIA and from controls without wheat allergy. Serum antibodies to crude gliadin extract (CGE) and purified ω‐5 gliadin were measured by ELISA and basophil reactivity by histamine‐release test. Gliadin‐induced cell‐mediated responses were assessed by lymphocyte proliferation assay, and cytokine mRNA expression with real‐time quantitative PCR.

Results All patients with WDEIA, but none of the controls, had IgE antibodies to CGE and ω‐5 gliadin. Both allergens released high levels of histamine from the basophils of patients with WDEIA. Levels of IgA antibodies to CGE and ω‐5 gliadin were significantly elevated in the patients, but the distribution of IgG subclass antibodies showed no statistically significant differences between the two groups. Proliferative responses of PBMC to CGE were increased in patients with WDEIA, and stimulation of PBMC with CGE caused, both in patients and in controls, a clear induction of IL‐10 mRNA. Compared with the controls, induction of IL‐10 mRNA expression in patients with WDEIA was significantly (P < 0.01) suppressed.

Conclusion These results suggest that, in addition to IgE antibodies against ω‐5 gliadin, specific IgA antibodies may be involved in the pathogenesis of WDEIA. Decreased expression of IL‐10 mRNA in PBMC during gliadin stimulation may facilitate the development of gliadin‐specific T cell responses.
Analysis of sequential immunoglobulin E‐binding epitope of Japanese cedar pollen allergen (Cry j 2) in humans, monkeys and mice
Authors: Tamura Y. , Kawaguchi J. , Serizawa N. , Hirahara K. , Shiraishi A. , Nigi H. , Taniguchi Y. , Toda M. , Inouye S. , Takemori T. , Sakaguchi M.
Published: March 2003

Background Japanese cedar (Cryptomeria japonica; CJ) pollinosis has been reported to occur naturally in Japanese monkeys (Macaca fuscata) as well as in humans. Most human patients and monkeys with pollinosis have specific IgE for Cry j 2, a major allergen of CJ pollen.

Objective The main purpose of this study was to identify IgE B cell epitopes of Cry j 2 using a synthetic peptide in humans, monkeys and mice.

Methods We synthesized 38 overlapping peptides that span the entire length of Cry j 2. We examined the B cell epitopes of Cry j 2 that are recognized by IgE in the sera of human patients and monkeys with pollinosis and immunized mice using synthetic peptides of Cry j 2. We also examined the reaction of Cry j 2‐specific mouse monoclonal IgG antibodies to the peptides. Furthermore, we conducted a histamine release assay with leucocytes from a pollinosis patient using human serum albumin (HSA) conjugated with the peptides as a B cell epitope.

Results We found that 16 of the 20 pollinosis patients who had specific IgE to Cry j 2 also exhibited IgE reaction with some Cry j 2 peptides. Of these 16 patients, 10 exhibited IgE reaction with Cry j 2 peptide no. 13 (121GQCKWVNGREICNDRDRPTA140). Five of the seven monkeys with CJ pollinosis exhibited a reaction with peptide no. 13. Furthermore, IgE in mice immunized with Cry j 2 and two mouse monoclonal IgG antibodies reacted with peptide no. 13. Peptide no. 13‐conjugated HSA showed the release of histamine from basophils. Furthermore, to determine the minimum epitope in peptide no. 13, we conducted an enzyme‐linked immunosorbent assay inhibition test. The core of the epitope in humans, monkeys and mice was 124KWVNGREI131.

Conclusion We found that 124KWVNGREI131 is an important B cell epitope recognized by IgE in humans, monkeys and mice.
Marked improvement of the basophil activation test by detecting CD203c instead of CD63
Authors: Boumiza R. , Monneret G. , Forissier M.‐F. , Savoye J. , Gutowski M.‐C. , Powell W. S. , Bienvenu J.
Published: March 2003

Background The flow cytometric basophil activation test by detection of CD63 expression has been developed as an alternative method for in vitro diagnosis of IgE‐mediated reactions to various allergens. Despite promising initial studies, the test remains disappointing in terms of sensitivity. CD203c has recently been demonstrated as a specific activation marker of basophils that is rapidly up‐regulated after allergen challenge in sensitized patients.

Objective The goal of the present study was to compare basophil activation tests by using either CD203c or CD63 in the diagnosis of immediate‐type allergy to latex.

Methods Twenty‐seven patients (health care workers of our institution) who developed clinical features evocative of allergy after contact with latex were included and classified into two groups. Group 1 (n = 16) comprised true allergic patients who presented with typical signs of immediate allergic reaction associated with a positive skin test (prick test). Group 2 (n = 11) consisted of patients whose clinical history was not typical and had negative skin test. Twelve healthy subjects were also studied as controls. We compared the sensitivity of two triple‐staining flow cytometric protocols measuring basophil activation after latex stimulation: CD45‐IgE‐CD63 and CD45‐IgE‐CD203c.

Results The CD203c protocol showed a higher sensitivity than the CD63 protocol (75% vs. 50%). In comparison, latex‐specific IgE sensitivity was found to be 69%. Furthermore, the magnitude of the basophil response was significantly higher with CD203c in comparison with CD63. Specificity was 100% for both protocols.

Conclusion Due to superior gating of basophils and a higher range of activation in response to allergen, the basophil activation test is markedly improved by use of CD203c instead of CD63.
Endemic (African) Kaposi's sarcoma presenting as a plantar tumour
Authors: Papadavid E. , Yu R. C. , Katsambas A. , Koumantaki E. , Chu A. C.
Published: March 2003

We present a case of the aggressive variant of African endemic Kaposi's Sarcoma (AKS) which presented as a large fungating and ulcerated plantar mass. Our patient responded extremely well to chemotherapy with no recurrence for 9 months after treatment completion. AKS is one of the most common cutaneous neoplasms in black Africans and although rare in Europe, it may be seen more frequently in the future because of the ease of international travel. The existing classification of KS into five different types (classic, African-endemic, iatrogenically immunocompromised patients, epidemic HIV-related and Mediterranean-endemic) cannot address fully the many anomalies described in the disease. The detection of a new herpes simplex-like viral DNA sequence (HHV-8) in different types of KS helps to explain some of the enigma described in this disease.
Searching for candidate genes in the new millennium
Authors: Bleck O. , McGrath J. A. , South A. P.
Published: March 2003

Completion of the entire sequence of the human genome is having a profound effect on the strategies biological scientists use to identify disease-associated genes. Laborious positional cloning approaches and traditional functional studies are gradually being transformed by emerging genomic and proteomic databases. Some of the exciting challenges investigators now face are the identification of new genes, determining the function of these genes, defining disease associations, and elucidating correlation between genotype and phenotype. To demonstrate how investigative methods for single-gene disorders are changing, we illustrate one possible approach in the search for the gene underlying the autosomal recessive genodermatosis, acrodermatitis enteropathica.
Superantigen activation of CD4+ and CD8+ T cells from HIV-infected subjects: role of costimulatory molecules and antigen-presenting cells (APC)
Authors: Vingerhoets J , Dohlsten M , Penne G , Colebunders R , Sansom D , Bosmans E , Kestens L , Vanham G
Published: March 2003

T cell receptor (TCR) triggering via superantigens induces decreased proliferative responses and increased apoptosis in T cells from HIV-infected patients compared with controls. Our aim was to delineate the role of intrinsic T cell defects, of APC dysfunction and of cytokines and costimulatory signal dysregulation in the deficient responses of CD4+and CD8+ T cells from HIV+ subjects to the superantigen Staphylococcus enterotoxin A (SEA). Proliferation and IL-2Rα up-regulation on SEA-stimulated CD4+and CD8+T cells in whole blood were reduced in HIV+ subjects with CD4 counts < 500, compared with controls. Neither addition of IL-2, IL-12 or phorbol myristate acetate (PMA) nor neutralization of endogenous IL-10, tumour necrosis factor-alpha (TNF-α), TNF-β or transforming growth factor-beta (TGF-β) could restore the decreased activation by SEA. Possible intrinsic T cell defects were studied by presenting SEA on HLA-DR-transfected Chinese hamster ovary (CHO) cells, co-expressing LFA3 and/or CD80, to purified T cells. In this system CD8+T cells from most HIV+ patients were hyporesponsive with regard to IL-2 production, IL-2Rα up-regulation and proliferation, whereas clearly reduced responses were only shown in CD4+T cells from AIDS patients. Similarly, apoptosis was increased in CD8+T cells from all patients, but only in CD4+T cells from AIDS patients. During HIV infection, the responses to TCR triggering through SEA are deficient in both T cell subsets. The intrinsic defect appears earlier during disease progression in purified CD8+T than in CD4+T cells, it occurs in conjunction with both CD2 and CD28 costimulation, and it is correlated with increased levels of apoptosis.
High levels of plasma IL-10 and expression of IL-10 by keratinocytes during visceral leishmaniasis predict subsequent development of post-kala-azar dermal leishmaniasis
Authors: Gasim S , Elhassan A M , Khalil E A G , Ismail A , Kadaru A M Y , Kharazmi A , Theander T G
Published: March 2003

Some patients develop post-kala-azar dermal leishmaniasis (PKDL) after they have been treated for the systemic infection kala-azar (visceral leishmaniasis). It has been an enigma why the parasites cause skin symptoms after the patients have been successfully treated for the systemic disease. We report here that PKDL development can be predicted before treatment of visceral leishmaniasis, and that IL-10 is involved in the pathogenesis. Before treatment of visceral leishmaniasis, Leishmania parasites were present in skin which appeared normal on all patients. However, IL-10 was detected in the keratinocytes and/or sweat glands of all patients who later developed PKDL (group 1) and not in any of the patients who did not develop PKDL (group 2). Furthermore, the levels of IL-10 in plasma as well as in peripheral blood mononuclear cell culture supernatants were higher in group 1 than in group 2.
Phenotypic changes in T cell populations during the reactivation of tuberculosis in mice
Authors: Howard A D , Trask O J , Weisbrode S E , Zwilling B S
Published: March 2003

The phenotypic changes of T lymphocytes during the reactivation of latent Mycobacterium tuberculosis infection by activation of the hypothalamic–pituitary–adrenal (HPA) axis was monitored using flow cytometric analysis. Subsets of CD4+ and CD8+ lymphocyte populations from the lung, spleen and draining lymph nodes of infected mice were identified based on their differential expression of the cell surface antigens CD44 and CD45RB. Latent infection was characterized by an accumulation of both naive, activated and memory CD4 and CD8 T lymphocytes in the lung and mediastinal lymph nodes. No changes were observed in the spleen of mice with latent infection when compared with uninfected mice. Immediately following the activation of the HPA axis, a reduction in all CD4+ and CD8+ T cells in the lung and mediastinal lymph nodes was observed. This correlated with the reactivation of mycobacterial growth. The decrease was transient for memory and naive CD4 and CD8 T lymphocyte populations in the lung. However, the number of naive CD4 and CD8 T lymphocyte populations in the mediastinal lymph node following reactivation was less than that found in mice with latent infection. These data provide the first characterization of T lymphocyte populations which may be functionally involved in the immunological response to HPA axis-induced reactivation of M. tuberculosis infection.
HLA class II phenotype controls diversification of the autoantibody response in primary Sjögren's syndrome (pSS)
Authors: Rischmueller M , Lester S , Chen Z , Champion G , Van Den Berg R , Beer R , Coates T , Mccluskey J , Gordon T
Published: March 2003

The coexistence of anti-La (SS-B) and anti-Ro (SS-A) autoantibodies in pSS is probably explained by intermolecular spreading of autoimmunity toward different components of the La/Ro ribonucleoprotein (RNP). In order to evaluate the role of the HLA class II phenotype in controlling diversification of this autoantibody response, 80 patients with pSS were typed by polymerase chain reaction sequence-specific oligonucleotide (PCR-SSO) at the HLA class II loci DRB1, DQA1 and DQB1. Serum samples were examined for anti-La and anti-Ro by counterimmunoelectrophoresis and by ELISA using purified recombinant La and 60-kD Ro proteins. Patient sera were classified according to the extent of diversification of the anti-La, anti-Ro response including the presence or absence of precipitating anti-La antibodies. Immunogenic characteristics of these stratified groups were then studied. All patients with pSS, with or without autoantibodies to Ro and La, were found to have at least one of the HLA-DRB1 types DR2, DR3 or DR5. The HLA DR3-DQA1*0501-DQB1*02 (DR3-DQ2) haplotype was primarily associated with a diversified La/Ro RNP response containing precipitating autoantibodies to La (P < 0.001); whereas the haplotype HLA DR2-DQA1*0102-DQB1*0602 (DR2-DQ1) was associated with a less diversified La/Ro RNP response containing non-precipitating (restricted epitope) anti-La autoantibodies (P < 0.001). Anti-La-positive patients lacking both HLA-DR2 and HLA-DR3 all expressed the HLA-DQA1*0501 allele, which was present at increasing frequency with greater diversification of the anti-La/Ro autoantibody response. The association of distinct HLA haplotypes with different degrees of autoantibody diversification in patients with pSS suggests a model of HLA-restricted presentation of La/Ro peptide determinants to autoreactive helper T cells. We propose that non-precipitating anti-La responses are driven by limited intermolecular help from DR2-DQ1-restricted T helper cells recognizing Ro determinants. On the other hand, we speculate that the more diversified, precipitating anti-La responses obtain more efficient cognate T help from DR3-DQ2-restricted T helper cells recognizing La determinants, where HLA-DQA1*0501 may be a critical determinant for antigen presentation.
Identification of a peptide inducing experimental autoimmune uveoretinitis (EAU) in H-2Ak-carrying mice
Authors: Namba K , Ogasawara K , Kitaichi N , Matsuki N , Takahashi A , Sasamoto Y , Kotake S , Matsuda H , Iwabuchi K , Ohno S , Onoé K
Published: March 2003

When certain strains of mice bearing H-2Ak are immunized with the interphotoreceptor retinoid-binding protein (IRBP), EAU is induced. Thus far uveitogenic determinant(s) has not been determined in the H-2Ak mouse system. In addition it is hard to prepare purified IRBP. In the present study, to circumvent these problems we attempted to identify uveitogenic peptides derived from bovine IRBP in H-2Ak haplotype mice. Six peptides which had been selected according to the H-2Ak binding motif (Dxxxxxxxx[A, R, T]) were synthesized. We report here that all the peptides are immunogenic but only one peptide, K2, which consisted of IRBP201–216 residues, induces EAU in various mice carrying H-2Ak. Amino acid substitution of K2 revealed that the core region interacted with both H-2Ak and T cell antigen receptor (TCR). The amino acid sequence of the core region derived from bovine IRBP was identical to the corresponding region of mouse IRBP. In addition, K2 appeared to be a natural peptide antigen processed from bovine IRBP. Altogether, we concluded that K2 is one of the natural autoantigens involved in induction of EAU in H-2Ak mice.
IgG anti-endothelial cell antibodies (AECA) in type I diabetes mellitus; induction of adhesion molecule expression in cultured endothelial cells
Authors: Triolo G , Triolo G , Accardo-Palumbo A , Carbone M C , Ferrante A , Casiglia D , Giardina E
Published: March 2003

AECA were detected in 25 of 71 patients with type 1 diabetes mellitus and in two of 33 healthy subjects. Patients with diabetes of < 1 year duration and those with long-standing disease had the highest levels of these antibodies. Inhibition studies suggest that at least part of the AECA reactivity is due to cross-reactive anti-ssDNA antibodies. AECA-positive sera were able to increase intercellular adhesion molecule-1 (ICAM-1) and E-selectin on human umbilical vein endothelial cells (HUVEC). Increased binding of polymorphonuclear (PMN) cells was also found to accompany raised E-selectin expression. Soluble ICAM-1 and E-selectin were also found to be increased in the sera of AECA-positive patients. An effect of AECA on endothelial cell function is suggested in diabetes mellitus.
Catalase and α-enolase: two novel granulocyte autoantigens in inflammatory bowel disease (IBD)
Authors: Roozendaal C , Zhao M H , Horst G , Lockwood C M , Kleibeuker J H , Limburg P C , Nelis G F , Kallenberg C G M
Published: March 2003

In IBD, the target antigens of anti-neutrophil cytoplasmic autoantibodies (ANCA) have not been fully identified, which limits the analysis of the diagnostic significance as well as of the possible pathophysiological role of these antibodies. In this study, we identify the target antigens of ANCA in large groups of patients with ulcerative colitis (UC) and Crohn's disease (CD). Apart from antibodies against lactoferrin and bactericidal/permeability-increasing protein (BPI), which have been reported before, antibodies against two novel granulocyte antigens were identified: antibodies against a 57/56-kD doublet were found in 38% of samples from UC patients and in 26% of samples from CD patients, whereas antibodies against a 47-kD protein were found in 10% of samples from UC patients and in 18% of samples from CD patients. Partial purification and amino acid sequence analysis identified the 57-kD protein as catalase and the 47-kD protein as α-enolase. This study is the first to report catalase and α-enolase as granulocyte antigens for autoantibodies in IBD.
Selective CD8+ T cells accumulate in the lungs of patients with allergic asthma after allergen bronchoprovocation
Authors: Wahlström J , Dahlén B , Ihre E , Wigzell H , Grunewald J , Eklund A
Published: March 2003

Our objective was to study whether CD4+ or CD8+ T cells expressing particular T cell receptors (TCR) would accumulate in the lungs of patients with allergic asthma following allergen exposure. We thus analysed the TCR Vα and Vβ gene usage of CD4+ and CD8+lung and peripheral blood lymphocytes (PBL) of eight patients with allergic asthma before and 4 days after inhalation challenge with the relevant allergen. Lung cells obtained by bronchoalveolar lavage (BAL) and paired PBL samples were analysed by flow cytometry using a panel of anti-TCR V-specific monoclonal antibodies that encompass ≈ 50% of the T cell repertoire. Lung-limited T cell expansions were recorded in both the CD4+and the CD8+subsets. In BAL CD8+, out of a total of 126 analyses, the number of T cell expansions increased from two to 11 after challenge, some of them dramatic. In BAL CD4+the frequency of expansions was moderately increased already before challenge, but remained unchanged. A few expansions that tended to persist were noted in PBL CD8+. When analysing the overall change in TCR V gene usage the largest changes were also recorded in the BAL CD8+subset. Specific interactions between T cells and antigens may lead to an increased frequency of T cells using selected TCR V gene segments. In this study we demonstrate that following allergen bronchoprovocation in allergic asthmatic subjects, T cell expansions preferentially emerge in the lung CD8+T cell subset.
Distinct modulation by interferon-gamma (IFN-γ) of CD23 expression on B and T lymphocytes of atopic subjects
Authors: Corominas M , Mestre M , Bas J , Buendia E
Published: March 2003

The low-affinity IgE receptor (FcεRII/CD23) plays a role in IgE production. Cytokines participating in IgE synthesis also modulate CD23 expression on lymphocytes, but whether this modulation is different in atopic subjects remains unclear. We studied CD23 expression on B and T lymphocytes in 10 asthmatic patients with Dermatophagoides pteronyssinus hypersensitivity and 10 healthy non-atopic subjects. Studies were performed by flow cytometry, in phytohaemagglutinin (PHA) or IL-4-stimulated mononuclear cell cultures, alone or in the presence of IFN-γ. Soluble CD23 (sCD23) released in the culture supernatants was measured by enzyme-linked immunoassay. Both PHA and IL-4 induced the expression of CD23 on lymphocytes of atopic and non-atopic subjects. Whereas PHA increased both the percentage and mean fluorescence intensity of CD23+ B and T cells, IL-4 alone did not increase the percentage of CD23+ T cells. The effects of IFN-γ were different in both groups, since it was able to reduce the percentage of PHA-stimulated CD23+ T cells only in non-atopic individuals. In non-atopic subjects more than atopic, levels of sCD23 were increased in the supernatants of PHA and IL-4 cultures. These results show that the modulation of CD23 expression is different on B and T cells, and that IFN-γ acts differently in atopic and non-atopic individuals.
Endogenous glucocorticoids modulate neutrophil migration and synovial P-selectin but not neutrophil phagocytic or oxidative function in experimental arthritis
Authors: Leech M , Hutchinson P , Holdsworth S R , Morand E F
Published: March 2003

Pharmacologic glucocorticoids are powerful inhibitors of the inflammatory response at many levels, including leucocyte trafficking and function. The adhesion molecule P-selectin is a key participant in polymorphonuclear neutrophil (PMN) migration to sites of inflammation. The extent to which endogenous glucocorticoids influence PMN migration and activation is not clear. We used the glucocorticoid receptor antagonist RU486 to examine the effect of endogenous glucocorticoid blockade on PMN migration and function in carrageenan monoarthritis in the rat. Arthritis was induced by intra-articular injection of carrageenan and disease severity measured by PMN count in synovial lavage fluid. Decalcified frozen sections of injected joints were analysed for expression of P-selectin by immunohistochemistry. Adrenal glucocorticoid action was blocked in vivo with RU486 20 mg/kg. PMN phagocytosis and reactive oxygen species synthesis were measured by flow cytometry. Carrageenan injection was associated with severe arthritis (synovial lavage PMN 5.9 ± 0.7 × 106, P < 0.01 versus control) which was dose-dependent. P-selectin was not detected in normal joints but was abundant in joints injected with 500 μg carrageenan. RU486 resulted in exacerbation of carrageenan arthritis (9.7 ± 0.8 × 106, P < 0.05). RU486 also altered the threshold for disease induction, in that most RU486-treated animals were susceptible to arthritis at a dose of carrageenan (2.5 μg) which did not induce arthritis in most control-treated animals (P < 0.05), denoting an altered threshold for arthritis induction. RU486 treatment was associated with increased synovial P-selectin expression. Activation status as measured by PMN phagocytic and oxidative function were not influenced by endogenous glucocorticoid blockade. These findings suggest that endogenous glucocorticoids selectively influence PMN migration to inflamed joints via P-selectin expression, but have no effect on PMN activation status.
T cell receptor (TCR) Vβ gene usage in bronchoalveolar lavage and peripheral blood T cells from asthmatic and normal subjects
Authors: Hodges E , Dasmahapatra J , Smith J L , Quin C T , Lanham S , Krishna M T , Holgate S T , Frew A J
Published: March 2003

T cells are thought to play an important regulatory role in asthma, but little is known about the T cell repertoire of the human lung or whether asthma is associated with any specific repertoire changes. Flow cytometry and MoAbs to TCR VB (TCRBV) families were used to quantify bronchoalveolar lavage (BAL) and blood T cells from normal and atopic individuals. Clonality was then assessed by polymerase chain reaction (PCR) amplification of cDNA and gene scanning using consensus and family-specific TCRBV primers and confirmed by sequence analysis. In addition, blood and BAL T cell populations were studied pre- and post-allergen challenge in four patients with allergic asthma. The majority of TCRBV families detected in blood by MoAb staining were also represented in BAL. While differences between BAL and blood populations were evident in each individual studied, these differences were not consistent between individuals or between CD4+ and CD8+ T cell subpopulations. These results are in broad agreement with other published studies, but in contrast to previous work we found a consistent difference between TCRBV7 family usage in blood and BAL in all individuals studied, and a consistently increased proportion of CD4+ BAL T cells bearing BV5S2/3 in asthmatics only. After allergen challenge, the pattern of TCRBV gene usage was largely unchanged as judged by flow cytometry. Gene scanning of PCR products generated from consensus VB primers revealed polyclonal lymphocyte populations in blood and BAL from all seven atopic individuals: in one normal tested polyclonal populations were found in blood and oligoclonal populations in BAL. Selected families amplified with family-specific primers BV5S2/3, BV6 and BV7 (chosen because of their predominance in BAL compared with blood) were more variable and revealed predominant polyclonal populations in blood and polyclonal or oligoclonal populations in BAL. In one asthmatic patient a clonal BV5S2 family was found in BAL. Following allergen challenge there were no significant changes in polyclonality/oligoclonality/clonality in three cases, but in one case a clonal BV5S2 population was found after challenge, that had not been evident beforehand. The lung T cell repertoire is thus broadly representative of blood T cells, but shows population differences that may result from response to persistent exposure to airborne antigens common to normal and atopic individuals. Oligoclonal TCRBV family expansion appears to be primarily lung-specific but independent of atopic asthma, although our challenge data in one case support the concept that clonal populations may follow local allergen challenge. These data are consistent with selection and amplification of specific T cell families in the lung in response to local antigenic exposure.
Pirfenidone induces intercellular adhesion molecule-1 (ICAM-1) down-regulation on cultured human synovial fibroblasts
Authors: Kaneko M , Inoue H , Nakazawa R , Azuma N , Suzuki M , Yamauchi S , Margolin S B , Tsubota K , Saito I
Published: March 2003

Pirfenidone has been shown to modify some cytokine regulatory actions and inhibit fibroblast biochemical reactions resulting in inhibition of proliferation and collagen matrix synthesis by fibroblast. We have investigated the effect of pirfenidone on the expression of cell adhesion molecules. The synovial fibroblasts were treated with IL-1α in the presence or absence of pirfenidone (range 0–1000 μm), and assayed for the expression of adhesion molecules such as ICAM-1 and endothelial-leucocyte adhesion molecule-1 (E-selectin) by cell ELISA. Pirfenidone significantly down-regulated the expression of ICAM-1 on cultured synovial fibroblasts in a dose-dependent manner. In contrast, expression of E-selectin was not affected. Furthermore, we examined whether pirfenidone affects the cellular binding between cultured lymphocytes and IL-1α-stimulated synovial fibroblasts by in vitro binding assay and found their mutual binding was significantly suppressed in a dose-dependent manner by pirfenidone. It is speculated that down-regulation of ICAM-1 might be one of the novel mechanisms of action of pirfenidone. These data indicate a novel mechanism of action for pirfenidone to reduce the activation of synovial fibroblasts.
Characterization of the murine immune response to the murine TSH receptor ectodomain: induction of hypothyroidism and TSH receptor antibodies
Authors: Vlase H , Weiss M , Graves P N , Davies T F
Published: March 2003

The thyrotropin receptor (TSHR) is the major autoantigen of human Graves' disease. In order to define the antigenicity of the TSHR in a defined model, we examined the immune response of BALB/c mice to immunization with a new bioactive, recombinant preparation of the ectodomain of the murine TSHR (mTSHR-ecd). Mice (n = 10) were immunized with 25–50 μg of insect cell expressed, purified and refolded, mTSHR-ecd in alum adjuvant containing pertussis toxin, on days 0, 21, 36, 50 and 70. Control mice received wild-type baculovirus-infected insect cell protein lysate, in a similar way. After 28 days, murine serum contained high titres of antibodies specific to mTSH-ecd and their titres continued to increase over 90 days. Antibody epitope mapping, using 26 peptides spanning the human TSHR-ecd, showed that a variety of regions of the ectodomain were antigenic. The earliest epitope included aa 22–41, but later two regions of reactivity were noted clustered towards the mid portion and carboxyl terminus of the ectodomain. The murine TSHR autoantibodies (TSHR-Abs) inhibited up to 78% of the binding of labelled TSH to native TSHR, demonstrating the presence of antibodies capable of blocking the native TSHR. We showed that these TSHR antibodies acted, in vitro, as TSH blocking antibodies, inhibiting TSH-induced generation of cyclic AMP in chinese hamster ovary (CHO) cells transfected with the hTSHR. Hence, the antibody response to mTSHR-ecd was potentially antagonistic in its influence on the TSHR. Assessment of thyroid function in the immunized mice showed a fall in serum total T3 by 90 days and markedly elevated murine TSH levels (from 64.0 to 239.6 ng/ml), confirming the onset of thyroid failure. However, thyroid histology remained grossly normal. These data demonstrate that mTSHR-ecd is a potent antigen with three major immunogenic regions. The induced mTSHR-Abs blocked TSH action in vivo and reduced murine thyroid function.
N-formyl-methionyl-leucyl-phenylalanine (fMLP) inhibits tumour necrosis factor-alpha (TNF-α) production on lipopolysaccharide (LPS)-stimulated human neutrophils
Authors: Vulcano M , Rosa M F Alves , Minnucci F S , Cherñavsky A C , Isturiz M A
Published: March 2003

During Gram-negative infections bacterial components, such as LPS and formylated peptides, exert profound physiological effects on polymorphonuclear neutrophils (PMN) resulting in increased neutrophil effector activities, including the generation of oxidative metabolites, degranulation, phagocytosis and cytokine release. There is not enough evidence about the relationships between LPS and formylated bacterial peptides in the triggering and regulation of the immune inflammatory response. In this study, we present evidence indicating that pretreatment of human PMN with a prototype formylated peptide such as fMLP results in the inhibition of TNF-α secretion, a key molecule that plays a central role in the pathogenesis of septic shock. This inhibitory effect of fMLP does not appear to alter the expression of LPS receptors or the transcriptional pathway of the TNF-α mRNA, but instead, fMLP reduces the expression of the membrane form of TNF-α on the PMN surface. These findings indicate that fMLP, a typical proinflammatory agent, could play, at least in determined conditions, an anti-inflammatory role.
Tumour necrosis factor (TNF) and TNF-related molecules in HIV-1+ individuals: relationship within vitroThl/Th2-type response
Authors: Rizzardi G P , Marriott J B , Cookson S , Lazzarin A , Dalgleish A G , Barcellini W
Published: March 2003

We examined the secretion and expression by peripheral blood mononuclear cells (PBMC) of TNF-α and TNF-related molecules with regard to Th1/Th2-type cytokine production. In 76 HIV+ patients at different disease stages and in 25 controls we measured cytokine (TNF-α/β, interferon-gamma (IFN-γ), IL-2, IL-4, IL-10), and activation marker secretion (sCD4, sCD8, sCD30) in phytohaemagglutinin (PHA)-stimulated and unstimulated PBMC cultures by ELISA, and membrane-bound TNF-α and CD30 expression by flow cytometry. We found an expansion of the TNF system in HIV+ individuals, that positively correlated with TNF-α, IFN-γ and sCD8, probably representing activation of the cytotoxic compartment. In advanced disease these correlations disappeared, and TNF-α and TNF-related molecules positively correlated with IL-10. Our results are in line with the hypothesis that an expanded TNF system is immunopathological in conjunction with Th2-type immunity in the advanced stage of disease and with the inexorable progression to disease seen when both IL-10 and TNF-α are elevated.
Regulation of cytokine expression by an autoreactive B cell clone derived from MRL/MP-lpr/lpr mice
Authors: Iwasaki T , Hamano T , Fujimoto J , Ogata A , Kakishita E
Published: March 2003

The B cell line, MRL159.5, was established by somatic hybridization between splenic MRL/MP-lpr/lpr (lpr) mice B cells and 2.52M, a hypoxanthine-aminopterine-thymidine (HAT) medium-sensitive B cell line mutant. It possessed a receptor molecule for mouse erythrocytes treated with bromelain (Br-MRBC) on its surface, likely to be an autoreactive B cell clone specific for Br-MRBC as detected by rosette-forming assay with Br-MRBC. MRL159.5 spontaneously produced IL-6 and secreted IgM, and was induced to augment IgM secretion when treated with Br-MRBC or IL-6. Triggering of CD40 led to an augmentation of IgM secretion as well as IL-6 expression. Blocking the binding of IL-6 to its cellular receptor through the use of inhibitory antibodies inhibited CD40-induced IgM secretion, suggesting a possible autocrine role of IL-6 for CD40-induced differentiation of this B cell hybridoma. Addition of IL-4 or Br-MRBC augmented IL-6 expression as well as IgM secretion by CD40-activated MRL159.5 cells. CD40 also augmented tumour necrosis factor-alpha (TNF-α) and granulocyte-macrophage colony-stimulating factor (GM-CSF) expression but resulted in decreased IL-10 expression. Furthermore, under conditions where IL-6 expression was augmented, IL-6Rα (gp80) expression was down-regulated, suggesting a negative feedback mechanism of an IL-6 autocrine loop in this hybridoma. These results demonstrate a role by which T cell-dependent activation through CD40 regulates an IL-6 autocrine loop, controlling differentiation of autoreactive B cells in autoimmune disease.