bluuebunny/crossref_metadata_2025 huggingface dataset:
Protection of islet cells from inflammatory cell deathin vitro
Authors: BURKART V , KOLB H
Published: August 2010

Islet cells cocultured with activated macrophages are lysed within 15 h in vitro. We showed previously that nitric oxide generated by macrophages is a major mediator of islet cell death. We have now probed several pathways to interfere with the chain of events leading to islet cell death. Scavenging of extracellular oxygen radicals by superoxide dismutase and catalase did not improve islet cell survival. Scavenging of extra- and intracellular oxygen radicals by two potent substances, citiolone and dimethyl-thiourea, also did not reduce islet cell lysis, while a lipid-soluble scavenger, probucol, provided partial protection. These findings argue against a synergistic action of nitric oxide and oxygen radicals in islet cell toxicity. The inhibition of poly(ADP-ribose)polymerase by 3-aminobenzamide significantly improved islet cell survival. Selective inhibitors of cyclooxygenase, such as indomethacin or acetylsalicylic acid, did not improve islet cell survival. Full protection was seen in the presence of NDGA, an inhibitor of lipoxygenase, and partial suppression was caused by BW755c, an inhibitor of both lipoxygenase and cyclooxygenase. We conclude that inflammatory islet cell death caused by activated macrophages involves the activation of arachidonic acid metabolism and of poly(ADP-ribose)polymerase, but that scavenging of oxygen free radicals provides little protection from lysis.
Correlation of serum cytokine and acute phase reactant levels with alterations in weight and serum albumin in patients receiving immunotherapy with recombinant IL-2
Authors: Deehan D J , Heys S D , Simpson W , Herriot R , Broom J , Eremin O
Published: August 2010

Recombinani IL-2 (rlL-2) has been used alone or in combination wiih other chemotherapeutic agents to enhance hosl defences against caneer. Prolonged administration of high doses, required for clinical efficacy, may precipitate serious dose-limiting loxicity. rlL-2-induccd ‘vascular leak syndrome’ leads lo hypotension, renal insufficiency, respiratory disturbances and other organ dysfunctions. Serial measurements of serunicylokincs and the acute phase protein C-rcactivc protein (CRP) were performed on nine palienls who received high-dose i.v. continuous therapy with rIL-2. The infiuence of these immunological parameters upon alleralions in patients' weight and serum albumin, as indicators of toxicity, was assessed. All patients experienced weight increases during the cycle (3-11% of total body weight). The serum levels of tumour necrosis factor (TNF-a) and CRP were highly predictive of aileralions in patients' weight (both P<0·001), while no correlation was found with lL-6 and weight change. Serum albumin tell linearly throughout the infusion cycle, but this showed no correlation with variations in serum levels of IL-6, TNF-α, or CRP. The complement components C3 and C4 were significantly reduced at thccndofthc infusion, suggesting a possible role for this cascade system in mediating ihesc clinical changes. The strong association between serum TNF-α and weight change, not previously documented, further supports the hypothesis that TNF-α is a key mediator in the pathogenesis of the ‘vascular leak syndrome’.
Photodynamic therapy; a comparison with other immunomodulatory treatments of adjuvant-enhanced arthritis in MRL-lpr mice
Authors: RATKAY L G , CHOWDHARY R K , NEYNDORFF H C , TONZETICH J , WATERFIELD J D , LEVY J G
Published: August 2010

Although numerous experimentat immunomodulalory regimens have been reported to be effective in the treatment of rheumatoid arthritis, they also produce undesirable side effects. An alternative specific modality of localized treatment is photodynamic therapy (PDT). In this study we treated 13-week-old MRL-lpr mice whose spontaneous arthritis was enhanced by intradermal injection of Freund's complete adjuvant (FCA). One group received transcutaneous photodynamic therapy at days 0, 10, and 20, following the FCA injection. The other groups were injected with 1 mg/kg per day indomethacin, 40 mg/kg per day cyclosporin A (CsA), or treated with 3 Gy sublethal whole body irradiation (WBI). The development of swelling was monitored for 1 month, at which time proteinurca, lymphadenopathy and the histopathology of the joints and kidneys were assessed. The results demonstrated that PDT and the conventional treatments significantly ameliorated swelling of the hindlimbs from 70%in the untreated FCA-injected animals to below the 19% level characteristic of the unmanipulated control. Histological examination showed a reduction in pannus fornamtion, and cartilage and bone destruetion, the characteristics of adjuvant-enhanced arthritis. PDT did not affect the survival rate, lymphoproliferation, or proteinuria of the treated animals. However, indomethacin increased proteinurea, and was less effective in preventing cartilage and bone destruction, furhtermore, lower doses of CsA and WBI exacerbated arthritis activity. These results indicate that photodynamic therapy can inhibit the development of adjuvant-enhanced arthritis in MRL-lpr mice with similar effectiveness to the conventional treatments, but without their negative side effects.
Epitope mapping of the 52-kD Ro/SSA autoantigen
Authors: FRANK M B , ITOH K , McCUBBIN V
Published: August 2010

Autoantibodies to Ro/SSA are commonly found in sera of patients with systemic lupus erythematosus (SLE) and primary Sjögren's syndrome. The presence of these antibodies is related to lymphopenia, photosensitive dermatitis, and pulmonary and renal disease, suggesting that they have an immunopathologic role [1-6]. We previously isolated a cDNA clone which encodes the 52-kD human Ro/SSA protein. In this study we have determined the number and location of epitopes recognized by SLF sera using recombinant proteins encoded by the full-length or overlapping subclones of this cDNA. An immunodominant epitope was detected using Western blots and ELISA on the NH:-terminal side of this protein's putative leucine zipper. The data suggest that 11 amino acid.s are critical for the recognition of this molecule by these autoantibodies. Although the titres of anti-52-kD Ro/SSA antibodies vary between different patient sera, no heterogeneity in the location of antigenic epitopes to which their autoantibodies bound was detected. This homogeneous pattern of reactivity to a single rather than multiple regions of this protein is unusual for lupus autoantigens which have been identified, and suggests that these antibodies may have arisen as by a cross-reaction to an epitope on another molecule.
Epitope mapping with synthetic peptides of 52-kD SSA/Ro protein reveals heterogeneous antibody profiles in human autoimmune sera
Authors: RICCHIUTI V , BRIAND J P , MEYER O , ISENBERG D A , PRUIJNJ G , MULLER S
Published: August 2010

The reactivity of autoantibodies present in the sera of 489 palicnts with Sjögren's syndrome (SS), systemic lupus crythematosus (SLE) and other autoimmune diseases was investigated by ELISA using recombinani 52-kD SSA/Ro protein (rRo52) and 39 overlapping synthetic peptides representing the entire sequence of Ro52. We report that IgG antibodies reacting with rRo52 were present in the sera of a large number of patients with SS (67% of patients with primary SS and 46% of patients with SS associated with SLE), whereas they were less frequent (10–25%) in SLE, rheumatoid arthritis (RA), juvenile chronic arthritis (JCA) and mixed connective tissue disease (MCTD), and absent in scleroderma. Among the 39 peptides tested, live were recognized by sera from 30–65% of patients with SS, namely peptides representing residues 2 11, 107 122, 107 126, 277 292 and 365 382. Patients with JCA had raised levels of IgG antibodies reacting with peptides 2 11 and 365 382, and 51% of patients with MCTD had raised levels of IgG antibodies reacting with peptide 365 382. None of the five peptides was recognized by more than 20% of sera from patients with SLE and RA. Interestingly, and of importance in the field of diagnostic tests based on peptides, the reactivity of antibodies to the Ro52 synthetic peptides varied greatly according to the origin of sera. Inhibition experiments using either patients' sera or antibodies induced in rabbits against Ro52 peptides showed that the four domains 2-11. 107 122, 277 292 and 365 382 are accessible on the surface of the Ro52 protein. These regions may thus be involved in the induction of specific antibodies in autoimmune patients.
Selective increase of activation antigens HLA-DR and CD38 on CD45RO+ T lymphocytes during HIV-1 infection
Authors: KESTENS L , VANHAM G , VEREECKEN C , VANDENBRUAENE M , VERCAUTEREN G , COLEBUNDERS R L , GIGASE P L
Published: August 2010

Infection with HIV results in a progressive depletion of CD4* T cells and leads to significant in vivo lymphocyte phenotype changes. In this regard, the expression of HLA-DR and CD38 on CD8* T cells has been shown to increase dramatically with disease progression. We investigated the expression of both aetivation markers on CD4* T cells in HIV-1-infected subjeets at different clinical stages of infection and compared the in vivo activation of CD4* T cells with parameters of viral activity and CD8* T cell activation. Eresh peripheral venous blood was obtained from 54 HIVinfeeted subjects and from 28 uninfected healthy controls. Three-colour immunophenotyping of the CD4’T Cell subset showed that the proportion of CD4* T cells expressing HLA-DR (10% in HIV negative controls) or CD38 (62%. in HIV-negative controls) was higher in asymptomatic (P < 0·05 for CD38) and symptomatic (P< 0.001 for HLA-DR and CD38) HIV-infected subjects than in controls, whereas the proportion of CD4* T cells expressing CD45RO (54% in controls) remained relatively unchanged. Simultaneous expression of HLA-DR and CD38 on CD4 * T cells increased from 2·3% in controls to 11% (P<0·001) in asymptomatic and 22% (P < 0·001) in symptomatic HIV-infected subjects. This relative increase of CD38 and HLA-DR expression occurred mainly on CD4* T cells co-expressing CD45RO. Changes in expression of HLA-DR and CD38 on CD4 * T cells correlated with similar changes on CD8 * T lymphocytes, with the presence of HIV antigen in the circulation, and with the disease stage of HIV infection.
HIV-1 induces tumour necrosis factor and IL-1 gene expression in primary human macrophages independent of productive infection
Authors: HERBEIN G , KESHAV S , COLLIN M , MONTANER L J , GORDON S
Published: August 2010

Cylokines such as tumour necrosis factor-alpha (TNF-a) and IL-Iβ may play a role in immunopalhogcncsis of AIDS, We studied early effects (05-48 h) of monocytotropic (ADA) or tymp ho tropic (1MB) strains of HIV-1 on TNF-α and IL-1β mRNA expression in primary human macrophages by a semi-quantitative reverse transcriptase-polymcrase chain reaction (RT-PCR) assay. Three-day-old monocyte-derived macrophages were exposed either to tissue culture supernatants containing virus (at multiplicity of infection (m.o.i.) of 005) or to control supernatants frceofvirionsandgpI20. ADA strain, but not IIIB. replicated in primary tissue culture-differentiated macrophages (TCDM). Soluble CD4 (sC D4) was used to inhibit binding of both strains to macrophages. We found that TNF-arand IL-lβ gene expression was induced by both strains 0-5-3 hafter addition of virus, and that enhanced expression of both cytokines was inhibited by sCD4. We conclude that C D4-dependcnl binding lo ihc cell surface is sufficient to enhance TNI′-α and ll.-lβ mRNA. whereas productive viral replication in primary human macrophages is not required. Therefore, similar pathways regulate gene expression of TNF-a and IL-Iβ by macrophages during initial infection by HIV-1 in vitro.
H-2b restriction of the immune response to the pl26Plasmodium falciparumantigen
Authors: BANIC D M , DELPLACE P , MAZINGUE C , CAMUS D
Published: August 2010

Inbred BALB/c (H-2d), CBA (H-2k) and C57Bl/6 (H-2%) mice immunized with Plasmodium falciparum schizonls or culture supernatcs develop antibodies of different anligcnic specificities. It has been observed that C57B1/6 mice were unable to produce deteelable antibodies against the pl26 antigen (native molecule and p73 or p50 processed fragments) compared with other inbred miee. Similar results were obtained using BALBeongenlc mice with a lack of p126 antibody response in H-2b mice, while H-2d and H-2k mice produced antibodies against the pl26. Lymphoeyte proliferation assays performed by incubation of spleen cells with immunopurified pl26 were positive for immunized BALB/c (H-2d) and congenic H-2d or H-2k mice. On the other hand, no lymphocyte stimulation was observed with either C57B1/6 (H-2b) or congenic H-2b miee. These results suggest an MHC restriction of the immune response against the entire pi 26 (found in schizonts) and its p73 and p50 naturally processed fragments (found in culture supernates).
Natural autoantibodies, IgG antibodies to tetanus toxoid and CD5+ B cells in patients with Mediterranean visceral leishmaniasis
Authors:   THE LEISHMANIA STUDY GROUP, LOUZIR H , BELAL-KACHMI L , SASSI A , LAOUINI D , BEN ISMAIL R , DELLAGI K
Published: August 2010

Natural autoantibodies (NaAb) and IgG antibodies to tetanus toxoid (TT) were analysed in the sera of 38 children with active visceral leishmaniasis (VL) previously vaccinated with TT and in 30 healthy controls matched for sex and age. Patients exhibited high levels of NaAb to a panel of self antigens (tubulin, myosin. myoglobin, actin) contrasting to a low level of IgG to TT. Analysis of the circulating B cells in 26 untreated patients showed a low percentage of CD5+ per total B cells (3–66%, mean 36·6%) compared with 14 normal conirols (17·8–66·6%, mean 52·7%)(P<0·001). Evaluation of these parameters after antimonial therapy showed a significant decrease of the level of the NaAb (P<0.0005), and a spontaneous increase of the level of the IgG to TT without any vaccine boosting (P<0·01). In contrast, there was a significant increase in CD5+ B cells (P<0·0005). This result suggests that CD5+ B cells may be sequestrated in parasitized lymphoid organs and may be released after remission. These findings show that the polyclonal B cell activation that occurs during active VL involves mainly B cells bearing NaAb and are in favour of a functional dichotomy of B cells.
Antimicrobial action of antibodies againstGiardia muristrophozoites
Authors: BELOSEVIC M , FAUBERT G M , DHARAMPAUL S
Published: August 2010

The activities of immune serum and trophozoite-specific MoAb were examined in vitro and in vivo. Immune serum and anti-Giardia muris MoAb caused immobilization of the trophozoites in vitro and were cytotoxic for trophozoites in the presence of exogenous complement. Both immune serum obtained from experimentally infected mice and anti-G. muris MoAb admmistered directly into the duodenum of mice significantly reduced the number of trophozoites in the small intestine during the acute phase of the infection. These results suggest that serum antibodies play a central role in the elimination of the primary Giardia infection.
Suppression of pulmonary injury in experimental ‘Goodpasture's syndrome’ by deoxyspergualin (DSP)
Authors: LAN H Y , NIKOLIC-PATHRSON D J , ZARAMA M , KERR P G , ATKINS R C
Published: August 2010

DSP is a potent immunosuppressive drug which can prevcnt allograft rejection and suppress acute rejection episodes. In this study, the ability of DSP to suppress pulmonary injury in experimental Goodpasture's syndrome was investigated. Passive accelerated anti-glomerular basement membrane (GBM) disease was induced in rats by priming with rabbit IgG. followed 5 days later by injection of rabbit anti-GBM serum (day 0). Groups of five animals were treated with DSP (5 mg/kg iniraperitoneally per day) or saline (untreated) from day 0 until being killed on days 1,7,14or21. At day I, both DSP-treated and untreated animals exhibited similar pulmonary haemorrhage, oedema, and prominent perivascular leucocyte infiltration. Untreated animals subsequently developed severe widespread pulmonary damage including granulomatous lesions and extensive fibrosis, which correlated with infiltration of macrophages and immune-activated (IL-2R′) mononuelcar cells (P<0·01). Tumour necrosis factor-alpha (TNF-α), a known mediator of acute lung damage, was produced by pulmonary mononuclear cells throughout the experimental course. In contrast, DSP treatment resolved pulmonary haemorrhage, prevented the appearance of granulomatous lesions, and resulted in a histologically normal lung structure by day 21. This improvement was associated with a marked suppression of maerophage infiltration (P<0·001 versus untreated), accumulation of immune activated (IL-2R′) mononuelear cells (P<0·05 versus untreated), and TNF-α production (P<0.05 versus untreated). DSP treatment also suppressed the deposition of rat anti-rabbit IgG immunoglobulin and C3 along the alveolar basement membrane (P<0·05 versus untreated). In conclusion, DSP suppressed pulmonary injury in accelerated anti-GBM disease by acting on the local cellular immune response and the systemic humoral immune response. Further studies are warranted to determine whether this could be a useful drug for the treatment of Goodpasture's syndrome in humans.
Expression of interferon-gamma (IFN-δ), IL-10, IL-12 and transforming growth factor-beta (TGF-β) mRNA in synovial fluid cells from patients in the early and late phases of rheumatoid arthritis (RA)
Authors: Bucht A , Larsson P , Weisbrot L , Thorne C , Pisa P , Smedegård G , Keystone E C , Grönberg A
Published: August 2010

The expression of immunoregulatory cytokines was investigated in freshly isolated synovial fluid mononuclear cells (SFMC) and peripheral blood mononuclear cells (PBMC) from patients with RA, using a quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) assay. IFN-γ, TGF-β, IL-10 and IL-12 (p40) transcripts were detected in SFMC of patients with early disease (<1 year duration) as well as in patients with long standing arthritis (>1 year). The expression of IFN-γ, IL-10 and IL-12 mRNA was increased in SFMC compared with RA PBMC. In addition, the expression was higher in RA SFMC than in PBMC from healthy control individuals. Immunoassay analysis of the secreted IL-12 heterodimer demonstrated increased levels in RA SF compared with levels found in serum from RA patients and control individuals. High levels of TGF-β mRNA were found in SFMC, but a significantly decreased TGF-β/β2-microglobulin (β2-M) ratio was found compared with PBMC from both patients and control individuals. IL-4 mRNA could not be detected, either in SFMC or in PBMC. Cytokine expression in RA PBMC did not differ from control PBMC, with the exception of a decreased TGF-β/β2-M ratio in RA patients with early disease. Our findings of IFN-7 mRNA and IL-12, but undetectable levels of IL-4 mRNA, suggest that the synovitis is characterized by a type 1 immune response. The presence of TGF-β and IL-10 mRNA indicates that immunosuppressive cytokines may also operate in the inflamed joint, although their level of expression may not be sufficient for down-modulation of immune activation.
A synthetic 10-kD heat shock protein (hsp10) fromMycobacterium tuberculosismodulates adjuvant arthritis
Authors: Ragno S , Winrow V R , Mascagni P , Lucietto P , Pierro F DI , Morris C J , Blake D R
Published: August 2010

The heat shock protein, hsp10, is an abundant protein in Mycobacterium tuberculosis (Mtb), its nucleotide sequence encoding a protein of 99 amino acids with a molecular mass of 10±7kD. This sequence is phylogenetically conserved, being represented by the GroES homologue of Escherichia coli. Hsp 10 and GroES are members of the chaperonin 10 family of molecular chaperones, and GroES is necessary for the optimal activity of GroEL, a member of the chaperonin 60 family and the E coli homologue of mycobacterial hsp65. Since hsp65 has been implicated in both experimental and human rheumatoid arthritis, we aimed to assess the immunomodulatory effects of its co-chaperonin, hsp10, in experimental arthritis. Our results show that an aqueous solution of a mycobacterial hsp10 delayed the onset and severity of adjuvant-induced arthritis in rodents when administered after disease induction but before joint involvement occurred. This biological activity was specific for the hsp10 of Mtb, since neither GroES nor the rat homologue was effective. Using synthetic hsp10 fragments, the activity was localized to the N-terminal region of the molecule. Assessment of circulating antibody levels to mycobacterial hsp10 and hsp65 indicated that all arthritic rats had increased litres to both hsp10 and hsp65: hsp10-treated rats showed further elevation of this humoral response not only to hsp10 but also to hsp65 when compared with the untreated arthritic control. This is the first report of the immunomodulatory activity of mycobacterial hsp10 in experimental arthritis, and exhibits a potential role for this co-chaperonin in pathophysiological situations.
Distribution of four polymorphisms in the tumour necrosis factor (TNF) genes in patients with inflammatory bowel disease (IBD)
Authors: Bouma G , Xia B , Crusius J B A , Bioque G , Koutroubakis I , von Blomberg B M E , Meuwissen S G M , Peña A S
Published: August 2010

In 153 patients with IBD, 64 with Crohn’s disease (CD), and 89 with ulcerative colitis (UC), as well as in 54 healthy controls (HC), the frequencies of four known di-allelic polymorphisms in the genes for TNF-α and lymphotoxin alpha (LTα) were investigated. In the Dutch population, the alleles of these four polymorphisms are present in only five combinations, called TNF haplotypes: TNF-C, -E, -H, -I, -P. Furthermore, the relation with the presence of perinuclear anti-neutrophil cytoplasmic autoantibodies (P-ANCA) was studied. A small, but statistically significant, association between the polymorphism at position -308 in the promoter region of the TNF-α gene and UC was found. The frequency of the uncommon TNF-α -308 allele 2 was found to be decreased in patients with UC compared with HC (allele frequency of allele 2 in UC patients 0±15 versus 0±25 in HC, P= 0±044). No significant differences in distribution of the TNF haplotypes were found between IBD patients and HC, although there was a tendency towards a higher frequency of the TNF-C haplotype in UC patients compared with controls (haplotype frequency 22%versus 13%; P= 0±19). No statistically significant differences in distribution of the TNF haplotypes were observed between P-ANCA-positive and P-ANCA-negative UC patients. The strength of the associations indicates that TNF genes are not markers for the predisposition to suffer from IBD. They may, however, be markers of subsets of patients with UC and CD.
Leucocyte activation by anti-lactoferrin antibodies bound to vascular endothelium
Authors: Peen E , Sundqvist T , Skogh T
Published: August 2010

Human polymorphonuclear neutrophil leucocytes (PMNL) prestimulated with the formylated tripeptide f-Met-Leu-Phe (fMLP) were activated to an immediate chemiluminescence (CL) response by polyclonal rabbit antibodies against human lactoferrin (Lf). This activation, indicating the formation of reactive oxygen species, was induced by intact IgG antibodies but could not be brought about by F(ab')2 fragments. Human Lf was also shown to adhere to the surface of cultured bovine aorta endothelial cells (BEC). When Lf-coated BEC grown on microcarrier beads were reacted with anti-Lf antibodies, an immediate CL response was achieved also with non-primed PMNL. Here, too, the reaction required intact IgG antibodies. Also, patient sera containing anti-Lf autoantibodies of IgG class were shown to activate fMLP-treated PMNL. The same effect was obtained (in a dose-dependent manner) with the gammaglobulin fraction from anti-Lf-positive patient serum. Further, anti-Lf-antibody-positive patient sera incubated with Lf-coated BEC beads were also able to activate non-stimulated PMNL to a chemiluminescence response. The results are discussed in relation to possible mechanisms of cell/tissue damage induced by anti-neutrophil cytoplasmic antibodies (ANCA).
Autoantibodies to human heat shock protein (hsp)60 may be induced by Escherichia coli groEL
Authors: Handley H H , Yu J , Yu D T Y , Singh B , Gupta R S , Vaughan J H
Published: August 2010

The 65-kD hsp from Mycobacterium tuberculosis has been reported to induce an autopathogenic subset of T cells in at least two animal models of autoimmune disease. Reports of increased expression of human hsp60 in the inflamed synovial tissue of rheumatoid arthritis (RA) patients, increased proliferation of RA synovial fluid T cells to mycobacterial hsp65, and increased levels of anti-mycobacterial hsp65 antibody in synovial fluid, have suggested that the highly homologous human (hu) hsp60 may be recognized as an autoantigen in RA patients. In the present study, we have examined by ELISA the serum IgG antibody levels to mycobacterial hsp65 and hu hsp60, as well as to the Escherichia coli hsp60, groEL, in patients with RA, systemic lupus erythematosus (SLE), Reiter’s syndrome, active tuberculosis, and normal controls. In all these groups, the levels of anti-groEL and anti-hu hsp60 were significantly higher than the anti-mycobacterial hsp65. Anti-hu hsp60 was positively correlated with anti-groEL, but not with anti-mycobacterial hsp65. Anti-hu hsp60 was competitively inhibited by either soluble groEL or hu hsp60, but little or none by mycobacterial hsp65. Reiter’s sera were found to have somewhat higher levels of anti-groEL and anti-hu hsp60 than did normal controls. We conclude that IgG anti-hu hsp60 autoantibodies arise primarily as a consequence of the humoral immune response to E. coli groEL through the recognition of cross-reactive epitopes.
Enhancing effect of oxygen radical scavengers on murine macrophage anticryptococcal activity through production of nitric oxide
Authors: Tohyama M , Kawakami K , Futenma M , Saito A
Published: August 2010

We examined the roles of reactive nitrogen intermediates (RNI) and reactive oxygen intermediates (ROI) in interferon-gamma (IFN-γ)-induced cryptococcostatic activity of murine peritoneal macrophages using NG-monomethyl-L-arginine (L-NMMA), a competitive inhibitor of RNI synthesis, and superoxide dismutase (SOD) and catalase, oxygen radical scavengers. IFN-γ-activated macrophages produced nitric oxide (NO) in a dose-dependent manner, as measured by increased nitrite concentration in the culture supernatant. IFN-γ also enhanced the suppressive effect on cryptococcal growth in a similar dose-dependent manner. The induction of killing activity and NO production by an optimal dose of IFN-γ (100 U/ml) was virtually suppressed by 500 μM L-NMMA. These results confirmed the importance of the RNI-mediated effector mechanism in anticryptococcal activity of macrophages. SOD and catalase significantly enhanced the cryptococcostatic activity of macrophages induced by a suboptimal dose of IFN-γ (20 U/ml). The augmenting effect of these reagents was mediated by NO, since they potentiated the production of NO by macrophages and their effects were totally blocked by L-NMMA. Our results indicate that the IFN-γ-induced anticryptococcal activity of macrophages is dependent mostly on RNI, and suggest that the ROI system down-regulates the effector mechanism for cryptococcostasis by suppressing the RNI system.
Allergenic epitopes of ovalbumin (OVA) in patients with hen’s egg allergy: inhibition of basophil histamine release by haptenic ovalbumin peptide
Authors: Honma K , Kohno Y , Saito K , Shimojo N , Horiuchi T , Hayashi H , Suzuki N , Hosoya T , Tsunoo H , Niimi H
Published: August 2010

We studied allergenic determinants that induce hypersensitivity to OVA, the major allergen in egg allergy, using immunoblot and histamine release assays. Immunoblot analysis demonstrated a part of the OVA epitope was in the C-terminal region comprising residues 347-385 (OVA347-385). Histamine was released from basophils of a patient with egg allergy upon stimulation with the OVA fragment corresponding to OVA347–385. Furthermore, detailed epitope mapping using overlapping peptides (residues 347-366, OVA-A; residues 357-376, OVA-B; and residues 367-385, OVA-C) in the OVA 347-385 region was carried out using the histamine release assay. In order for histamine release from basophils to occur, the allergen must possess two or more allergenic determinants located on the protein molecule at distances that would be equivalent to the distances between IgE molecules on the membrane surface. These results suggest that there are at least two epitopes that bind IgE antibodies on each OVA peptide. In addition, one epitope that binds IgE antibodies in two patients appears to reside in the haptenic peptide OVA357-366 (OVA-B1). The histamine release from basophils stimulated by OVA-B was completely inhibited by OVA-B1 in one of these patients. Similarly, OVA-B1 inhibited the histamine release produced by OVA-A in the other by more than 40%. These results suggest that haptenic synthetic peptides could regulate the allergic reaction in the effector phase if common epitope(s) recognized by IgE antibodies in the patients with egg allergy can be found. These are the first studies that provide an antigen-specific approach to inhibiting histamine release from basophils by a haptenic peptide recognized by IgE antibodies in an allergic disorder.
Effects of leukotriene C4 and D4, histamine and bradykinin on cytosolic calcium concentrations and adhesiveness of endothelial cells and neutrophils
Authors: Heimbürger M , Palmblad J E W
Published: August 2010

We compared the effects of leukotrienes B4, C4 and D4 (LTB4, C4 and D4) in vitro, as well as of histamine and bradykinin, on adhesive interactions between cultured umbilical vein endothelial cells (HUVEC) and polymorphonuclear neutrophils (PMN) and on cytosolic calcium transients, [Ca2+]i. in vitro. LTB4, but not LTC4 or LTD4 (at 1-100 nM), increased HUVEC adhesiveness for PMN, maximally 2.8-fold; in addition, PMN adhesion was augmented by LTB4 (but not by LTC4 and LTD4) to a plastic surface. Rapid, but smaller increments of HUVEC (but not of PMN) adhesiveness were induced by histamine and bradykinin (at 10 μM). Nonetheless, LTC4 and LTD4 (at 100 nM) induced rapid rises of [Ca2+]i in HUVEC, whereas γδ+100-fold higher concentrations were needed of histamine and bradykinin for similar rises. In PMN LTD4 (and LTB4) induced rapid increases of [Ca2+]i, whereas no significant effect was seen with LTC4, histamine or bradykinin. The [Ca2+]i responses to LTC4 and LTD4 were inhibited by the peptidoleukotriene receptor blocker SKF 104,353. Thus, LTB4 and the peptidoleukotrienes display disparate profiles as inducers of adhesion and calcium transients in PMN and HUVEC, indicating discrete differences in the stimulus response coupling for these closely related leukotrienes.
In vitroT cell unresponsiveness following low-dose injection of anti-CD3 MoAb
Authors: Ben-Amor A , Leite-De-Moraes M C , Lepault F , Schneider E , Machavoine F , Arnould A , Chatenoud L , Dy M
Published: August 2010

Anti-CD3 MoAb treatment is widely used as an immunosuppressive therapy. In the present study we examined the in vitro T cell response in mice having received 24 h before a single i.v. injection of 10 μg of anti-CD3 MoAb. We found that splenocytes from these mice displayed a dramatically decreased proliferative response to the T cell mitogens concanavalin A (Con A), anti-CD3, phytohaemagglutinin (PHA) and phorbol myristate acetate (PMA) + calcium ionophore, while the effect of lipopolysaccharide (LPS) was not impaired. T cell suppression persisted for about 10 days after anti-CD3 injection, returning to normal within 15 days. The F(ab')2 fragment of anti-CD3 had no such effect, indicating the requirement for in vivo activation. At the dose used, anti-CD3 resulted neither in T cell depletion nor in down-modulation of the CD3 T cell receptor (TCR) complex. The low proliferation was also not explained by apoptosis, following secondary challenge with Con A. Splenocytes from anti-CD3-injected mice were highly responsive to IL-2, but generated little or no IL-2, IL-3, IL-4 and interferon-gamma (IFN-γ) when exposed to Con A. Normal cytokine production could not be restored by the addition of optimal doses of IL-2 during Con A stimulation. Transforming growth factor-beta (TGF-β) was the only cytokine whose mRNA expression was not modified in stimulated splenocytes from anti-CD3-injected mice. Furthermore, anti-TGF-β antibodies increased Con A-induced T cell proliferation, but not cytokine production.
Effect ofin vivoactivation of natural killer (NK) cells by a tilorone analogue on the survival of mice injected intravenously with different experimental murine tumours
Authors: Algarra I , González A , Pérez M , Gaforio J J , Garrido F
Published: August 2010

We studied the effect of a tilorone analogue (RMI 10,874DA) and anti-asialo GM1 serum on the survival of BALB/c and C57B1/6 mice after i.v. injections of different syngeneic murine tumour cells. Tumour lines used were different clones from chemically (GR9 wild type, GR9.B9, B7.1.B4, B7.1.B5, B7.2.38), and ultraviolet light (GRUV3)-induced sarcomas; B16 melanoma and LSTRA and YC8 lymphomas. Pretreatment of mice with tilorone inhibited metastatic colonization and increased survival significantly in all cases. In some tumour systems, the effect was attenuated when high numbers of cells were injected. Abrogation of NK cells with anti-asialo GM1 serum significantly decreased (in all tumours and at different cell doses) survival in comparison with untreated mice injected with tumours, regardless of cell dose used. These results clearly suggest that NK cell activation in vivo by the tilorone analogue we tested prolongs survival and inhibits metastasis formation in mice, even when pretreatment consists of a single dose of the analogue.
Humanized anti-CD4 monoclonal antibody therapy of autoimmune and inflammatory disease
Authors: ISAACS J D , BURROWS N , WING M , KEOGAN M T , REBELLO P R U B , WATTS R A , PYE R J , NORRIS P , HAZELMAN B L , HALE G , WALDMANN H
Published: August 2010

We have investigated the biological and therapeutic properties of a humanized anti-CD4 MoAb, hlgGl-CD4, in patients with refractory psoriasis and rheumatoid arthritis (RA). hIgGl-CD4 is a modulating, non-depleting MoAb, which induced a first-dose reaction in most patients treated. It provided brief symptomatic relief in both conditions, and psoriasis appeared easier to control with conventional agents after MoAb therapy. At the doses used, hIgGl-CD4 did not synergize therapeutically with the pan-lymphocyte MoAb CAMPATH-1H (C1H) in patients with RA treated sequentially with both agents. There were no serious adverse effects definitely attributable to therapy. Our results are compared with those of other CD4 MoAb studies, and factors influencing the outcome of therapy are discussed.
Polyclonal T cell elimination by prolonged immunostimulation in an experimental model
Authors: GALDIERO F , GALDIERO M , NUZZO I , VITIELLO M , BENTIVOGLIO C , ROMANO-CARRATELLI C
Published: August 2010

An experimental model of immunological deficiency obtained by treating mice for 6 months with serum of human blood drawn from different healthy individuals has been studied. The results show that an alteration of a circulating lymphocyte population with alterations of the ratio CD4+/CD8+ appeared in mice stimulated for a long period with immunogens. Mice treated for 2–4 months showed an increase in B lymphocytes and a decrease in the total number of T lymphocytes, with a decrease in CD4+ lymphocytes and an increase in CD8+ lymphocytes. After 4 months, the CD8+ lymphocyte population started to decrease, with a ratio of CD4+/CD8+ reaching almost 1. In animals treated for 2–3 months, the mean survival time (MST) following experimental infection with Salmonella typhimurium presented a decrease to 5 days, and after 5–6 months of treatment presented a decrease to 3-2-5 days. The bacteraemia was modified in comparison with controls. Prolonged exposure to antigens also induced lymphocyte apoptosis: cells of animals treated for 4–6 months presented increased levels of apoptosis with a percentage that reached 30–35%. A semiquantitative evaluation of the level of heat shock protein (hsp) in splenic lymphocytes showed an increase in the presence of hsp60 and hsp70 in the first 3 months of treatment, which then remained constant for up to 6 months.
Cryptococcus neoformansinfection in mice previously infected with LP-BM5 MuLV, the agent of murine AIDS (MAIDS)
Authors: LACROIX C , CHAU F , CARBON C , SINET M , DEROUIN F
Published: August 2010

We studied susceptibility to experimental systemic cryptococcosis in mice previously infected with the retroviral complex LP-BM5 (responsible for murine AIDS). LP-BM5 was inoculated to C57B1/6 mice by intravenous (i.v.) injection 8 weeks before an i.v. challenge with 4×l03 CFU of Cryptococcus neoformans. Uninfected and singly infected mice were used as controls. LP-BM5 infection did not result in a significant increase in fungal burdens in the lungs or brains of co-infected animals compared to mice infected with C. neoformans alone. However, mortality was enhanced in the co-infected animals. The kinetics of splenocyte subsets differed in co-infected mice and LP-BM5-infected mice; the increase in CD4+, CD8+ and Ly5+ cells was only moderate in the former. Cytokine production by concanavalin A (Con A)-stimulated splenocytes from co-infected mice showed a marked decrease in the Thl response (IFN-γ, IL-2) and an increase in the Th2 response (IL-4, IL-10). Furthermore, cryptococcosis altered the course of MAIDS, inhibiting splenomegaly. This effect was not related to a decrease in ecotropic virus titres in the spleen or to improved in vitro responsiveness of spleen cells to Con A. The marked decrease in IFN-γ production in co-infected animals could partly explain the inhibition of LP-BM5-induced splenomegaly. This model of murine retroviral infection does not seem to be suitable for studying cryptococcosis in immunosuppressed animals, but remains valuable for investigating in vivo interactions between two pathogens.
IgA nephropathy-specific expression of the IgA Fc receptors (CD89) on blood phagocytic cells
Authors: TOYABE S , KUWANO Y , TAKEDA K , UCHIYAMA M , ABO T
Published: August 2010

We analysed the biochemical features of receptors for the Fc-region of IgA (FcαR, CD89) on blood monocytes and granulocytes of patients with IgA nephropathy (IgAN). FcαR on monocytes of IgAN were found to have a higher Mr (60-80kD) than those of control monocytes (50–75 kD) and granulocytes (55–75 kD) in both IgAN and controls as shown by immunoprecipitation analysis. Removal of N-linked carbohydrates from FcαR on monocytes of IgAN revealed a 32–36 kD protein core, the Mr of which was still higher than that of controls (28–32 kD). When FcaL transcripts were analysed by reverse-transcription-PCR, only one prominent band was visualized in PCR products from IgAN monocytes. Since the results thus far show that IgAN monocytes express FcαR protein and mRNA differently from granulocytes and control monocytes, PCR products were then cloned and sequenced. The predominant band in PCR products from IgAN monocytes was identical to that of the FcαR a.l transcript, and an additional 10 transcripts containing five novel transcripts were obtained from granulocytes and control monocytes. In three transcripts, we found an insertion sequence between the S2 and EC1 domains, suggesting the existence of a new exon. These results suggest a predominant usage of FcαR a.l among various transcripts of FcαR in IgAN monocytes.
Local macrophage proliferation in the pathogenesis of glomerular crescent formation in rat anti-glomerular basement membrane (GBM) glomerulonephritis
Authors: LAN H Y , NIKOLIC-PATERSON D J , MU W , ATKINS R C
Published: August 2010

Glomerular crescent formation is a feature of aggressive forms of glomerulonephritis. The conventional view of crescent formation within Bowman's space involves proliferation of parietal epithelial cells and the recruitment of blood monocytes. However, the potential role of local macrophage proliferation in this process has not been investigated. The current study examines macrophage proliferation within Bowman's space on the basis of expression of the proliferating cell nuclear antigen (PCNA) in a rat model of crescentic glomerulonephritis (accelerated anti-GBM disease). ED1+ macrophages accounted for 42% of cells within early cellular crescents, and 38% of these crescent macrophages were proliferating on the basis of PCNA expression. Macrophages became the dominant cell population in advanced cellular and fibrocellular crescents (64–71%), and there was a significant increase in the level of macrophage proliferation, with 62% and 67% of ED1+ macrophages expressing the PCNA, respectively. This high level of macrophage proliferation was confirmed by incorporation of bromo-deoxyuridine and the presence of mitotic figures within crescents. Indeed, macrophages accounted for 73% of all proliferating cells within advanced and fibrocellular crescents. Macrophage proliferation within Bowman's space was a local event, as shown by a lack of proliferating monocytes in the circulation, the presence of mitotic figures within crescents and a reciprocal relationship between the numbers of ED1+PCNA+ cells within Bowman's space compared with that in the capillary tuft during the progression from early to advanced and fibrocellular crescents. In conclusion, this study has changed the conventional view of the pathogenesis of crescent formation in glomerulonephritis with the demonstration of substantial local macrophage proliferation within Bowman's space. It is proposed that local proliferation is a major mechanism of macrophage accumulation within crescents and plays an important role in the progression of epithelial-dominated early cellular crescents to macrophage-dominated advanced and fibrocellular cellular crescents.
Recombinant proteinase 3 (Wegener's antigen) expressed inPichia pastorisis functionally active and is recognized by patient sera
Authors: HARMSEN M C , HEERINGA P , VAN DER GELD Y M , HUITEMA M G , KLIMP A , TIRAN A , KALLENBERG C G M
Published: August 2010

The open reading frame of human proteinase 3 (PR3) without the prepro-peptide was cloned and expressed in Escherichia coli (rcPR3) and in Pichia pastoris (rpPR3). The 6-histidine tagged rpPR3 was efficiently secreted into culture supernatant from which it could be purified by immobilized metal chelate chromatography. Purified rpPR3 migrated as a single 32-kD band on SDS-PAGE and harboured protease activity that could be inhibited with inhibitors specific for serine-proteases. By indirect antigen-capture ELISA using rpPR3, 60% of sera from patients with Wegener's granulomatosis bound to the recombinant product, although it was not recognized in ELISA with directly coated rpPR3.
Elevated soluble Fas/APO-1 (CD95) levels in silicosis patients without clinical symptoms of autoimmune diseases or malignant tumours
Authors: TOMOKUNI A , AIKOH T , MATSUKI T , ISOZAKI Y , OTSUKI T , KITA S , UEKI H , KUSAKA M , KISHIMOTO T , UEKI A
Published: August 2010

Soluble Fas (sFas) is produced as translation products of alternative mRNA splicing, and antagonizes the membranous Fas molecule in Fas/Fas ligand interactions. We investigated the serum sFas levels in 64 Japanese silicosis patients with no clinical symptoms of autoimmune diseases or malignant tumours, using ELISA for sFas. The serum sFas levels in the silicosis patients were significantly higher than those in healthy volunteers. Elevated serum sFas levels were also detected in patients with systemic lupus erythematosus but, unexpectedly, no difference was observed in sFas levels between progressive systemic sclerosis patients and healthy volunteers. On the other hand, there was no significant difference in the expression of Fas on peripheral blood lymphocytes between the patients with silicosis and age-matched healthy volunteers. These observations provided the first evidence that serum sFas levels are elevated in silicosis patients without clinical symptoms of autoimmune diseases or malignant tumours. It remains to be clarified whether patients with elevated sFas levels have a tendency to develop autoimmune diseases later, or whether some other distinct factor(s) is necessary to initiate the progression of autoimmune diseases.
IL-7 sensitizes human pre-B cells but not pro-B cells to Fas/APO-1 (CD95)-mediated apoptosis
Authors: LEVY Y , BENLAGHA K , BUZYN A , COLOMBEL M , BROUET J-C , LASSOUED K
Published: August 2010

Homeostasis of human B cell development is maintained by a complex network of cytoplasmic and surface expressed molecules. Abnormalities in this process may result in the expansion of malignant B cell precursors in B lineage acute lymphoblastic leukaemia (ALL). ALL cells share surface antigens with normal early precursor B cells. We have studied here the role of Fas/APO-1 (CD95) antigen on leukaemic precursor B cell line growth and survival, and the modulation of its effects by signals involved in normal early B cell development. Four ALL cell lines representative of the early steps of B cell differentiation are shown to express surface Fas/APO-1 (CD95) antigen and to undergo apoptosis in the presence of anti-Fas cross-linking antibodies. This effect is strongly enhanced when pre-B, but not pro-B cells, are pretreated with IL-7 but not with IL-2, IL-3, IL-4 or IL-10. Furthermore, pre-B cell death induced by anti-Fas antibodies in combination with IL-7 is increased upon pre-B receptor but not CD19 cross-linking. Bcl-2 and Bax protein expression is not influenced by IL-7 or pre-BR stimulation in either pro-B or pre-B cell lines. These results indicate that signals involved in normal early B cell development can modulate the Fas (CD95)-mediated apoptosis of leukaemic precursor B cells.
Inhibition of interleukin-8 production in human endothelial cells byStaphylococcus aureussupernatant
Authors: Tajima A , Seki K , Shinji H , Masuda S
Published: August 2010

Recent reports have shown that Staphylococcus aureus infection increases the expression of cytokines and cell adhesion molecules in endothelial cells and enhances leucocyte migration, thereby resulting in bacterial elimination. In this study, we analysed the production of the chemokine interleukin (IL)-8 in human umbilical vein endothelial cells (HUVEC) infected with several S. aureus strains by using reverse transcription–polymerase chain reaction and enzyme-linked immunosorbent assay. We found that the avirulent strains (00–51 and 00–62) increased IL-8 production but the virulent strains (A17 and A151) decreased it at both the mRNA and protein levels. We considered that the inhibition of IL-8 production depended on certain inhibitory factor(s) secreted by bacteria. This was because S. aureus also abolished IL-8 expression in HUVEC treated with cytochalasin D, and the addition of culture supernatants of strains A17 and A151 decreased IL-8 production in HUVEC. This factor(s) in the bacterial culture supernatant inhibited both basal and tumour necrosis factor (TNF)-α-induced IL-8 production. In contrast, no inhibitory effect was observed on monocyte chemotactic protein-1 (MCP-1) production. These results indicate that S. aureus can down-regulate IL-8 release in endothelial cells through the secretion of inhibitory factor(s), and this may result in decreased neutrophil recruitment, thus interfering with the host immune response to bacterial infection.