bluuebunny/crossref_metadata_2025 huggingface dataset:
Functional activities of synthetic anaphylatoxic peptides in widely used biological assays
Authors: KOLA A , KLOS A , BAUTSCH W , KRETZSCHMAR T , KÖHL J
Published: July 2010

A comparison study was carried out between the modern ATP release assay (ARA) with guinea-pig platelets and the traditional guinea-pig ileum contraction assay (ICA). The biological activities of the anaphylatoxin C3a and synthetic C3a analogue peptides were determined in both assays. In dose-response curves with C3a, a human C3a peptide with the last 21 amino acids of the C terminus (C3a 56–77) and a peptide with 13 amino acids which was acylated N-terminal with the aromatic fluorenylmethoxycarbonyl group and an aminohexanoyl group (Fmoc-Ahx YRRGRAAALGLAR) were tested. The ARA turned out to be 100 times more sensitive than the ICA. In contrast to previous reports the 21 amino acid long C3a analogue peptide did not exhibit full C3a activity but only 7% (ARA) or 12% (ICA). The potentiation of biological activity in the ARA by coupling non-peptide acyl-residues N terminal to peptidic C3a analogues could be confirmed with Fmoc-Ahx-YRRGRAAALGLAR in the ICA. In addition, the tri-peptide Fmoc-Ahx-LAR displayed C3a specific activity in the ICA demonstrated by desensitization experiments.
The concentration of the C-type lectin, mannan-binding protein, in human plasma increases during an acute phase response
Authors: THIEL S , HOLMSKOV U , HVIID L , LAURSEN S B , JENSENIUS J C
Published: July 2010

Two ELISAs for estimating mannan-binding protein (MBP) were constructed and the concentration of MBP in plasma was followed in patients undergoing major surgery and in patients having a malarial attack. In both cases increases of MBP in the plasma were observed. The relative increase and the kinetics varied from person to person. The concentration of MBP increased between 1·5- and three-fold following surgery. In some patients an increase was seen at day 1 whereas in others the increase was not observed until days 3–9. In the malaria patients an increased level of MBP was maintained during 30 days of treatment with chloroquine. The relative increase in MBP was independent of the presurgery or premalaria levels.
Haemodialysis as a model for studying endogenous plasma DNA: oligonucleosome-like structure and clearance
Authors: RUMORE P , MURALIDHAR B , LIN M , LAI C , STEINMAN C R
Published: July 2010

The rale of clearance of extracellular plasma DNA in man has important implications for palhogenetic mechanisms in systemic lupus erythematosus (SLE). as well as for certain other clinical states. Present knowledge of this parameter is derived exclusively from studies of injected, naked DNA in animals. Recent information indicates that the physiologic form of plasma DNA in SLE is that of oligonucleosome-like molecules rather than of naked DNA and consists of mullimeric complexes of DNA bound to histone. probably arising from an apoptolic process. In order to study the rate at which these oligonucleosome-like complexes are removed from plasma and to do so in man rather than experimental animals, we exploited the observation that during haemodialysis large amounts of DNA arc released, apparently within the dialysis coil, into the patient's plasma. Since this release appears to cease promptly with termination of the procedure, it offered the potential for estimating the rale of removal of such DNA from human plasma. Moreover, If that DNA. as postulated, were shown to possess an oligonucleosome-like structure resembling that found endogenously in human SLE, the relevance of such information to the human disease state would be further enhanced. The present results support the conclusion that DNA released into plasma during haemodialysis possesses such an oligonucleosome-like structure. The plasma half-life of that DNA in man was found not to exceed 4 min. The highly dynamic state thus implied for extracellular endogenous plasma DNA in man has important implications for pathogenelie mechanisms dependent on dsDNA in SLE. Moreover, individuals undergoing chronic haemodialysis. who are thereby exposed to a very large cumulative amount of such DNA, might serve as models for studying its long-term sequelae.
Hodgkin's cells express a novel pattern of adhesion molecules
Authors: ELLIS P A , HART D N J , COLLS B M , NIMMO J C , MacDONALD J E , ANGUS H B
Published: July 2010

Adhesion molecules play an important role in the functioning of the immune system, particularly with regard to cell-cell interactions and antigen presentation. Several adhesion molecules are expressed on Hodgkin's disease-derived cell lines and these arc important in their molecular interactions as antigen presenting cells (APC). There are no data regarding the expression of many of these adhesion molecules on Reed-Slernbcrg cells and its mononuclear variant (Hodgkin's cells (HC)) present in pathological material. To obtain this information we undertook an immunohistolo-gical study on material from 18 cases of Hodgkin's disease using a panel of MoAbs to examine the expression of adhesion molecules on HC. The HC were shown to express the integrin β1 subfamily molecules. LFA-I (CD11a) and p150,95 (CD11c)in high density but lacked CR3(CD11b). All of the immunoglobulin gene superfamily adhesion molecules studied were present to some degree on HC. with ICAM-2, in particular, showing moderate to strong expression in most cases. The Hermes antigen CD44 was present in high density but leukosialin (CD43), another molecule present on diverse leucocyte types, was. in general, not detected on HC. These new data showing that ICAM-1, ICAM-2 and LFA-3 are, like LFA-1, expressed on HC emphasize the ability of HC to act as APC. The known adhesion molecule phenotype of the recently defined haematopoietic lineage of human dendritic cells (DC) is broadly similar to that of HC. perhaps supporting the hypothesis that some HC represent a malignancy of an APC (DC) lineage.
Structure and expression of themb-1transcript in human lymphoid cells
Authors: LEDUC I , PREUD'HOMME J-L , COGNÉ M
Published: July 2010

The mb-1 gene encodes a protein associated with membrane-bound immunoglobulins (mlg) and it has been suggested that it may play a role in signal iransduction. Using a murine probe, we cloned a human complementary DNA homologous to the murine mb-1 sequence. Its complete sequence is in full agreement with a recently published human cDNA sequence but differs from a previously reported partial sequence. We studied mb-1 expression in human cells at various maturation stages. Large amounts of a single 1·4 kb transcript were detectable in B cell lines carrying mlg of the μ, γ, α1 or α2 isotype. The mb-1 mRNA was also expressed in prc-B cells and in cells expressing truncated membrane μ chains devoid of associated light chains. Only trace amounts of mb-1 mRNA were found in tissue samples containing numerous plasma cells, while no mRNA was delected in several plasmacytoma cell lines, indicating that expression is shut down in plasma cells. No signal was found in T cells or in non-lymphoid tissues. Altogether, these results show that the human mb-1 gene is expressed in prc-B cells and B lymphocytes, regardless of the isotype of the mlg heavy chain and is no longer expressed in plasma cells.
Characterization of cytokine gene expression in CD4+ and CD8+ T cells after activation with phorbol myristate acetate and phytohaemagglutinin
Authors: LEUNG J C K , LAI C K W , CHUI Y L , HO R T H , CHAN C H S , LAI K N
Published: July 2010

Cytokinesare important mediators involved in the development of effector cells and in the regulation of immune responses. The gene expression of these mediators in T cell subset has yet to be fully elucidated. Using sensitive reverse transcription-polymerasc chain reaction (RT-PCR). the kinetics of cytokine gene expression in human CD4+ and CD8+ T cells were examined. CD4+ T cells were more readily activated by phorbol myrislatc acetate (PMA) and phytohaemagglutinin (PHA) than CD8+ T cells in terms of the IL-2 receptor (IL-2R) mRNA expression. Quantitative differences in cytokine gene expression between CD4+ and CD8+ T cells were confirmed and higher levels of cytokine mRNAs were induced in CD4+ than in CD8+ T cells. Early induction of IL-2 mRNA was observed in both T cell subsets. The demonstration of diffcrenl kinetics of cytokine gene expression illustrates one of the examples of the complexity of immunoregulation. The differential response of cytokine gene expression in different T cell subsets should be taken into consideration when clinical studies in cytokine production by peripheral blood mononuclcar cells arc interpreted.
Interference of Wegener's granulomatosis autoantibodies with neutrophil Proteinase 3 activity
Authors: van de WIEL B A , DOLMAN K M , van der MEER-GERRITSEN C H , HACK C E , von dem BORNE A E G Kr , GOLDSCHMEDING R
Published: July 2010

Classic anti-neutrophil cytoplasmic autoantibodies (C-ANCA) are disease-specific markers of Wegener's granulomatosis (WG). The possible pathogenetic role of these autoantibodies, which are directed against Proteinase 3 (PR3), is not yet clear. We studied the effect of C-ANCA on PR3 proteolytic activity and on the complcxation of PR3 with alpha1-antitrypsin (α1AT). C-ANCA IgG from eight patients with active WG significantly inhibited PR3 proteolytic activity, particularly towards elastin (median 84.2% inhibition). C-ANCA IgG significantly inhibited the complexation of PR3 with α1AT (median 58.8% inhibition). Moreover, addition of purified PR3 to C-ANCA-positive sera from WG patients yielded less complexes with α1AT (median 44.8%) compared with sera containing perinuclear anti-neutrophil cytoplasmic autoantibodies (P-ANCA) or ANCA-negative sera. These findings indicate the existence of a hitherto unknown property of C-ANCA, which may be of importance in the pathogenesis of WG.
The B cell repertoire in patients with systemic autoimmune diseases: analysis of Epstein-Barr virus (EBV)-inducible circulating precursors that produce autoantibodies against nuclear ribonucleoprotein (nRNP)
Authors: OKAWA-TAKATSUJI M , AOTSUKA S , UWATOKO S , SUMIYA M , YOKOHARI R
Published: July 2010

Peripheral blood B cells from patients with systemic autoimmune disease and healthy volunteers were immortalized using EBV and the frequencies of B cell precursors that produced immunoglobulin class-specific antibodies against anti-nRNP, a specific marker for mixed connective tissue disease, were assessed using limiting dilution analysis. The frequencies of EBV-induced B cell precursors that produced IgG anti-nRNP were correlated closely with the serum titres of the corresponding autoantibodies, which indicates that B cell precursors that produced potentially pathogenic autoantibodies could be immortalized from the peripheral blood of the patients by EBV. In contrast, the frequency of EBV-induced B cell precursors that produced IgM anti-nRNP in patients with systemic autoimmune disease was comparable to that in healthy volunteers and greater than those that produced IgG and IgA anti-nRNP. Moreover, many of the clones that produced IgM antibodies against nRNP reacted with other autoantigens, such as double-stranded DNA, single-stranded DNA and rabbit IgG. These polyreactive IgM antibodies are believed to belong to the ‘natural antibodies’, to be coded by the germline immunoglobulin V genes, and to react with evolutionarily conserved structural cellular components, including nRNP. Our finding that nRNP is one of the target antigens for this polyreactive autoantibody may lead to the elucidation of the origin of the pathogenic IgG and IgA anti-nRNP antibodies found in sera from patients with systemic autoimmune diseases.
Fibroblast growth factors in connective tissue disease associated interstitial lung disease
Authors: THORNTON S C , ROBBINS J M , PENNY R , BREIT S N
Published: July 2010

Fibrosis is a major cause of morbidity and mortality in chronic inflammatory diseases, especially interstitial pulmonary disorders. Fibroproliferation is an important part of this fibrotic response, and is mediated largely through growth factors such as platelet-derived growth factor (PDGF), insulin-like growth factor (IGF) I and tumour necrosis factor-alpha (TNF-α). Although there is some evidence implicating these cylokines in fibrotic disorders, strong evidence in vivo is almost nonexistent. In order to ascertain the role that these factors play in inflammatory lung disorders associated with connective tissue diseases, alveolar mononuclcar cells have been obtained from subjects by bronchoalveolar lavage and assessed for the spontaneous release of fibroblast growth factors. The study population consisted of subjects with a variety of different connective tissue disorders, both with and without inflammatory pulmonary complications. It was found that lavage cells spontaneously secreted fibroblast growth factor activity over 24 h with maximum activity detected at 6 to 12 h. Growth factor activity could be detected in most subjects with connective tissue disease-associated inflammatory lung disease and some normal subjects, but the amount of growth factor activity was much higher in the former than in the latter. By means of antibody depletion experiments all growth factor activity from lavage cells of normal patients was attributable to TNF-α while patients with interstitial lung disease secreted large amounts of PDGF and fibronectin in addition to TNF-α. Approximately 40–50% of the total released growth factor activity could be accounted for by PDGF, and 100% by the combination of PDGF. TNF-α and fibronectin. While TNF-α is released from the bronchoalveolar lavage cells of many subjects, in addition, many patients with interstitial lung disease also release spontaneously, large amounts of fibroblast growth factor activity attributable to PDGF and fibronectin.
MRL/lpr→ severe combined immunodeficiency mouse allografts produce autoantibodies, acute graft-versus-host disease or a wasting syndrome depending on the source of cells
Authors: ASHANY D , HINES J J , GHARAVI A E , MOURADIAN J , DRAPPA J , ELKON K B
Published: July 2010

MRL/lpr (lpr) mice spontaneously develop a lupus-like illness as well as massive lymphadenopathy. Attempts to transfer autoimmunity by adoptive transfer or radiation bone marrow chimeras have been unsuccessful. Since severe combined immunodeficiency (SCID) mice have been engrafted with human and rat xenografts without apparent grafl-versus-host disease (GVHD), we subjected SCID mice to low-dose irradiation and reconstituted the mice with spleen cells from young or oldlpr mice or withlpr bone marrow. Fourteen out of twenty (70%) of SCID mice engrafted with spleen cells from oldlpr mice produced autoantibodies (anti-DNA and anti-Sm) without evidence of the severe lymphoid atrophy previously described forlpr spleen +/+chimeras. SCID mice engrafted with spleen cells from younglpr mice developed acute GVHD and 5/6 (83%) died within 4 weeks post-transfer. Although 8/11 (73%) of lpr→ SCID bone marrow allografts survived for at least 4 months, these mice developed a wasting disease characterized by lymphoid atrophy and fibrosis without the production of autoantibodies. None of the lpr→ SCID grafts resulted in the transfer of double negative T cells or the lymphoproliferative syndrome characteristic of MRL/lpr mice. These findings indicate that SCID mice can be engrafted with splenocytes from old MRL/lpr mice and that B cells continue to secrete autoanlibodies for several months in the SCID recipients. This study also demonstrates that, unlike i.p. transplant of xenogeneic cells, acute GVHD is a consistent feature of i.p. transplants of normal allogeneic mononuclear cells into SCID mice.
Anti-neutrophil cytoplasmic autoantibodies in patients with symptomatic HIV infection
Authors: KLAASSEN R J L , GOLDSCHMEDING R , DOLMAN K M , VLEKKE A B J , WEIGEL H M , SCHATTENKERK J K M EEFTINCK , MULDER J W , WESTEDT M L , VON DEM BORNE A E G KR
Published: July 2010

Antibodies against cytoplasmic antigens of neutrophils, producing perinuclear (p-ANCA) as well as cytoplasmic staining with central accentuation (c-ANCA), have been described in non-HIV-infected patients with specific pathology such as glomerulonephritis and vasculitis. Here, we report on a patient with a vasculitis-like syndrome and a positive ANCA-test who appeared to he infected by HIV. Further analysis revealed that ANCA, p-ANCA as well as c-ANCA without central accentuation can be demonstrated in the serum of HIV+ individuals. In a cross-sectional study on individuals indifferent stages of HIV infection, we found that the occurrence of ANCA was limited to the symptomatic stages of HIV infection: p-ANCA was found in one out of 10 ARC patients and in two out of II AIDS patients with malignancies (AIDS-MAL), but not in AIDS patients with opportunistic infections (AIDS-OI). c-ANCA was found in four of the ARC patients, in two of the 14 AIOS-OI patients and in two AIOS-MAL patients. The presence of ANCA was not related to the degree of hypergammaglobulinaemia nor to specific symptomatology. ANCA containing sera from HIV+ individuals did not read with HEp2 cells nor with cytoplasmic antigens of lymphocytes, natural killer (NK) cells or eosinophils. Five out of the 11 (two p-ANCA and three c-ANCA) sera reacted weakly with cytoplasmic antigens of moncytes. All sera reacted with karyoplasts but not with cytoplasts prepared from neutrophils. These results suggest that HIV-ANCA might be directed against myeloid cell-specific granule constituents. However, sandwich-ELISAs with MoAbs against granule antigens that are frequently the target antigens of ANCA in HIV individuals were negative. Also immunoprcecipitation and immunoblotting, using lysates of neutrophil granules, did not allow further identification of the target antigens of HIV-ANCA.
Frequencies of HIV-reactive B cells in seropositive and seronegative individuals
Authors: ZUBLER R H , PERRIN L H , DOUCET A , ZHANG X , HUANG Y-P , MIESCHER P A
Published: July 2010

Peripheral blood mononuclear cells (PBMC) from HIV-infected seropositive (HIV+) but not from normal, seronegative (HIV-) individuals are known to produce anti-HIV antibodies in vitro, in the absence or presence of pokeweed mitogen (PWM). Previous studies showed that up to 20–40% of spontaneously immunoglobulin-secreting B cells from HIV+ individuals are HIV-specific. To analyse the frequency of anti-HIV B cells among “total” peripheral blood B cells in the present study, we used a limiting dilution assay in which EL-4 thymoma cells induce clones of immunoglobulln-secreting cells in activated as well as resting B cells. Anti-HIV B cells were detected not only in 11/12 HIV+ individuals (with frequencies from 1/910 lo 1/21 500 B cells cultured; one negative test was from a person undergoing seroconversion), but also in 4/9 HIV normal blood donors (1/16200 to 1/49000 B cells cultured) and in 3/6 newborns from HIV mothers (1/11 800 to l/26 600 B cells cultured). The mean frequency was nine times higher in the HIV individuals than in the normal donors. As in previous studies, only the cells from HIV individuals generated anti-HIV antibodies in PBMC bulk cultures with or without PWM. The relative proportion of specific anti-HIV antibody total immunoglobulin in PBMC bulk cultures was 800 times higher by the mean than in EL-4 B cell cultures from HIV individuals (whereby the total immunoglobulin secretion for equal numbers of B cells cultured was 500 times lower for PBMC). These different results obtained with different assays suggest that in seropositives most anti-HIV B cells belong to an activated B compartment which is quite small, even in a disease with B cell hyperactivity. Therefore, the specific B cells are strongly diluted among the EL-4 cell-responsive, total B cells. On the other hand, the EL-4 assay can detect HIV-reactive B cells in the B ceil repertoire of normal, non-infected individuals.
LFA-1-dependent OKT3-driven T cell clusters in common variable immunodeficiency
Authors: RUDNICKA W , ENGLISH N , FARRANT J , NORTH M E , BRYANT A E , EDWARDS A J , STACKPOOLE A , WEBSTER A D B , BALFOUR B M
Published: July 2010

The triggering of the TCR/CD3 complex by anti-CD3 (OKT3) antibody leads to the formation of T cell clusters. In cultures of T lymphocytes from most normal individuals, the peak of cluster formation occurs at 24 h. but with cells from patients with common variable immunodeficiency (CVI) it was seen earlier al 4–9 h; in addition, the clusters were larger than normal, particularly at 9 h. Cluster formation by CVI and normal cells was dependent on temperature and divalent cations, but did not require Fc receptors. Since OKT3 clustering is known to be dependent on the LFA-l/ICAM-l adhesion system, the effect of monoclonal antibodies directed against these molecules was tested. A potent inhibitor was the antibody against the common beta chain of the integrin family (CD 18). But of four MoAbs against the alpha chains (CD 11), three inhibited and one stimulated T cell aggregate formation. Increased expression of LFA-I or ICAM-1 on CVI patients'T cells could not be demonstrated. The accelerated clustering was therefore probably due lo an increase in the proportion of cells carrying the activated form of LFA-1. The formation of large numbers of homotypic lymphocyte clusters might reduce the effective interaction between Band T cells, thus contributing to the depression of immunoglobulin synthesis observed in this disease.
IL-1-like production in adriamycin-induced nephrotic syndrome in the rat
Authors: BRICIO T , MOLINA A , EGIDO J , GONZALEZ E , MAMPASO F
Published: July 2010

Rats receiving a single dose of adriamycin (7·5 mg/kg) develop heavy proteinuria and morphological abnormalities similar to those observed in minimal change nephrotic syndrome in humans. IL-1-concomitance between enhanced I-a display by resident glomerular macrophages. IL-1-like cytokine secreted by whole isolated rat glomeruli and proteinuria was observed in adriamycin-injected rats during the experimental protocol. In addition, in vitro studies have shown that after stimulation with adriamycin or lipopolysaccharide (LPS) this cytokine is mainly produced by resident glomerular macrophages in culture. Although the precise mechanism of proteinuria in this model needs to be further studied, our results indicate that IL-1-like cytokine could be an important mediator implicated in the structural and functional disturbances occurring at the glomerular capillary wall level in adriamycin nephrosis.
An anti-peptide antibody that recognizes a neo-antigen in the CR1 stump remaining on erythrocytes after proteolysis
Authors: BARBOSA J E , HARRISON R A , BARKER P J , LACHMANN P J
Published: July 2010

Previous studies of erythrocyte CR1 levels in systemic lupus erythematosus (SLE) and other diseases with in vovo complement activation have led lo the conclusion that CR1 levels fall because of loss of CR1 from erythrocytes by proteolysis —predominantly in the liver. In order to measure the existence of proteolysed CR1 remnants on erythrocytes an antibody was raised to a peptide corresponding to the CR1 sequence between the proximal standard consensus repeat (SCR) and the transmembrane segment. This antipeptide antibody recognizes a neo-antigen found on trypsinized erythrocytes which has been demonstrated to represent the “CRI-stump”, The anti- ‘CR1-stump’ antiserum detects proteolysed CR1 on the ex vivo erythrocytes of a patient with cold haemolytic antibody disease (CHAD). However, higher affinity antibodies will be needed to make anti- CR1 -stump a satisfactory diagnostic reagent.
Inhibition of the reactive proliferation of lymphocytes by activated macrophages: the role of nitric oxide
Authors: DENHAM S , ROWLAND I J
Published: July 2010

The effects of nitric oxide synthesis by activated macrophages on concanavalin A (Con A) stimulated lymphocyte proliferation and the modulation of these events by extraneous l-arginine concentration were investigated. In 1 mM or 3 mM exogenous l-arginine, inhibition of proliferation of a fixed number of lymphocytes was progressively inhibited in the presence of increasing numbers of macrophages. This inhibition was related to increased nitric oxide synthesis by the macrophages and was suppressed in the presence or NG-monomethyl-l-arginine (NMMA), a specific inhibitor of nitric oxide synthesis. Inhibition of nitric oxide synthesis by 500 μM NMMA was less effective at high concentrations of macrophages, and in 5 mM as compared with 1 mM l-arginine. In the absence of exogenous L-arginine, NMMA inhibited lymphocyte proliferation in the presence of low numbers of macrophages but appeared to promote proliferation at high macrophage concentrations. Membrane separation of lymphocytes and macrophages led to loss of the nitric oxide mediated inhibitory effect on lymphocyte division except at the highest concentrations of macrophages used. Inhibition of lymphocyte proliferation could not be associated with l-arginine depiction of the media by macrophages or by the action of nitrite ions, a product of nitric oxide oxidation.
Soluble IL-2 receptor levels in patients with Graves'ophthalmopathy
Authors: PRUMMEL M F , WIERSINGA W M , VAN DER GAAG R , MOURITS M P , KOORNNEEF L
Published: July 2010

In various autoimmune diseases circulating levels of soluble 1L-2 receptor (sIL-2R) seem to be related to disease activity. Because reliable parameters of disease activity in Graves' ophthalmopathy are lacking, we measured sIL-2R levels in 47 patients with this disorder, The patients had Graves' disease, but no other immune-mediated diseases, had not yet received specific treatment for their ophthalmopathy and were euthyroid during the entire study period. Twenty-one of the 47 patients (45%) had sIL-2R values above the upper normal limit of 650 U/ml. as established in 20 healthy controls. There were no differences between patients with normal (median 469, range 280–644 U/ml) and elevated (median 946, range 678–1588 U/ml) sIL-2R levels regarding duration or severity of the eye disease (as assessed clinically from the total eye score). However, patients with severely enlarged eye muscles had higher sIL-2R values than patients with less severely enlarged eye muscles on CT scan. Patients with elevated sIL-2R tended to have a higher response rate (71%) to a 3-month course of prednisone, than those with normal levels (46%; P=0081). Since a successful outcome of prednisone treatment might be representative for disease activity, the elevated sIL, −2R levels seem to reflect active inflammation. Although the practical relevance of this finding in individual patients is limited, it underscores the importance of cell-mediated immune responses in this thyroid-related eye disease.
Limiting-dilution analysis of T cell reactivity to mycobacterial antigens in peripheral blood and synovium from rheumatoid arthritis patients
Authors: CRICK F D , GATENBY P A
Published: July 2010

Limiting-dilution analysis (LDA) was used to quantify the frequency of Mycobacterium bovis BCG-and 65-kD-reactive T cells in paired samples of peripheral blood and synovial tissue from patients with rheumatoid arthritis, The frequency of BCG-reactive T cells detected in the peripheral blood of patients ranged from 1/585 to 1/7639 versus a control frequency range of 1/480 to 1/6773, The frequency of such cells in the synovium was found to be much lower than it was in peripheral blood; in fact, in 80% of patients synovial BCG-reactive T cells were not detected. The frequency of 65-kDreactive cells in the peripheral blood of each individual was lower than the frequency of BCG-reactive cells (range 1/3738 to 1/55 324), as would be expected. However, no synovial 65-kD-reactive cells were detected from any of the patients studied. The LDA assay for the 65-kD antigen was consistent with the single hit model, that for BCG was not. The relatively high proportion of mycobacterial-reactive precursors seen in the peripheral blood of non-vaccinated individuals may reflect a population of cells induced either by natural environmental exposure to mycobacteria or, given the highly conserved nature of heat shock proteins across phylogeny, by some other infection. The results also suggest that the frequent finding of reactivity to proteins such as the 65-kD heat shock protein contained within BCG may not be a generalized phenomenon in rheumatoid synovium.
Low-affinity antibodies against collagen type II produced by lymph node cells are associated with pathology in collagen-induced arthritis in rats
Authors: RAHMAN J , LOH J , STAINES N A
Published: July 2010

The relationship between the affinity of antibodies against type II collagen (CII) and arthritis was studied in rats immunized intradermally with bovine CII. Disease was associated with a higher mean titre of serum antibody and a lower mean functional antibody affinity (determined in a chaotropic dissociation assay) against both the immunizing bovine CII and homologous autoantigenic rat CII in comparison with the response in immunized rats that did not develop disease. The functional affinity of the antibodies present in the serum was found to correlate with that of antibodies produced in culture by cells from the lymph nodes draining the site of immunization with collagen. The reduction in mean functional affinity in the anti-collagen response may be the result of the increased production of antibodies of the lowest affinity and a consequent broadening of the affinity heterogeneity. It is proposed that production of low-affinity antibodies in the lymph nodes draining the site of immunization with collagen is important in the pathogenesis of collagen-induced arthritis in rats.
Effect of macrophage activation on killing ofListeria monocytogenes.Roles of reactive oxygen or nitrogen intermediates, rate of phagocytosis, and retention of bacteria in endosomes
Authors: HIGGINBOTHAM J N , LIN T L , PRUETT S B
Published: July 2010

The role of macrophage activation in the killing of L. monocytogenes is unclear. Some studies suggest that activation for enhanced production of reactive oxygen and nitrogen intermediates may not be of central importance. Recent data have indicated an important role for interferon-gamma (IFN-γ) induced retention of L. monocytogenes in endosomes. Data from the present study indicate that proteose peptone-elicited macrophages from DBA2/J, CD-1, and C3H/HeN mice are listericidal. Activation of these ceils in vitro or 20 h by IFN-γ (20 or 500 U/ml) increased HM2O2 or nitrite production, but did not increase the number of L. monocytogenes killed during a subsequent 6-h or 7-h culture. Incubation of macrophages with IFN-γ plus lipopolysaccharide (LPS) caused greater activation and increased the number of Listeria killed during a 6-h or 7-h culture. However, this seems primarily attributable to enhanced phagocytosis. Proteose peptone-elicited macrophages were significantly more effective than resident macrophages in preventing the escape of L. monocytogenes from endosomes into the cytoplasm. This capability was not significantly enhanced by IFN-γin vitro. but was enhanced by IFN-γ plus LPS. This correlates well with the effects of these activation stimuli on killing of L. monocytogenes by proteose peptone-elicited macrophages. These results indicate that enhanced retention of L. monocytogenes in endosomes is induced by proteose peptone elicitation and that further macrophage activation in vitro by IFN-γ does not improve listericidal activity.
Tumour necrosis factor-dependent parasite-killing effects during paroxysms in non-immunePlasmodium vivaxmalaria patients
Authors: KARUNAWEERA N D , CARTER R , GRAU G E , KWIATKOWSKI D , DEL GIUDICE G , MENDIS K N
Published: July 2010

Plasmodium vivax malaria infections in non-immune individuals manifest as periodic clinical episodes of fever with chills and rigors known as paroxysms. We have demonstrated that in non-immune patients the period of paroxysm is associated with the transient presence of plasma factors which kill gametocytes, the intra-erythrocytic sexual stages of the malaria parasite which transmit the infection from humans to mosquito, rendering them non-infectious to mosquitoes. Gametocytc killing in paroxysm plasma is mediated by tumour necrosis factor (TNF) acting in conjunction with other essential serum factor(s). Plasma TNF levels were elevated during a paroxysm. In semi-immune individuals from a P. vivax-endemic area clinical symptoms of malaria are mild and the parasite killing factors are not induced during paroxysm. Serum TNF levels were correspondingly lower in endemic patients during a paroxysm. Human peripheral blood mononuclear cells (PBMC) can be stimulated in vitro by extracts of P. vivax blood stage parasites to produce TNF and associated parasite killing factor(s), thus simulating in vitro the events that occur during a paroxysm, this being the release of parasite exo-antigens by rupturing schizonts and the subsequent induction of PBMC to produce TNF and other parasite-killing factors. We were able to show that convalescent serum from P. vivax semi-immune individuals block the induction of TNF and parasite-killing factors by malaria antigens in vitro, presumably through antibodies that neutralize parasite exo-antigens. Thus, individuals living in malaria-endemic areas appear to acquire clinical immunity to malaria by avoiding their induction during infection; we have shown that one such mechanism is the neutralization of parasite exo-antigens that induce the production of parasite killing factors.
Evidence for transfer of cellular and humoral immunity to cytomegalovirus from donor to recipient in allogeneic bone marrow transplantation
Authors: BOLAND G J , VLIEGER A M , VERVERS C , De GAST G C
Published: July 2010

In order to study the importance of the immune status of the donor in the development of immunity after allogeneic bone marrow transplantation (BMT), we monitored 23 cytomegalovirus (CMV) antibody-positive BMT recipients for humoral and cellular immunity to CMV, of whom 12 had a CMV antibody-positive and 11 a CMV antibody-negative marrow donor. Lymphocyte proliferation to CMV recovered significantly earlier after BMT in recipients of marrow from a CMV+ donor (10·4 weeks after BMT) compared with the recipients of marrow from CMV- donors (16·7 weeks after BMT, P<0·05). This seemed to be specific, as lymphocyte proliferation to phytohaemagglutinin and Candida were not different between the two groups. IgM responses after active infection were seen in both groups, but initial IgG rises without IgM were seen only in recipients of marrow from CMV+ donors (P<0·05). Lymphocyte proliferative or humoral immune responses to CMV were not detected in any of the patients in a control group consisting of nine CMV- recipients. These results indicate that T cell memory to CMV is transferred with donor marrow from CMV+ donors, leading in most patients to direct IgG anti-CMV responses and to quicker recovery of cellular immunity to CMV.
Class- and subclass-specific pneumococcal antibody levels and response to immunization after bone marrow transplantation
Authors: LORTAN J E , VELLODI A , JURGES E S , HUGH-JONES K
Published: July 2010

Immunoglobulin class- and subclass-specific antibodies to a polyvalent pneumococcal capsular polysaccharide vaccine (Pneumovax II) were measured before and after immunization in children, 1 year or more after bone marrow transplantation for a variety of genetic disorders. The median titres of specific IgG, IgG1 and IgG2 pneumococcal antibodies fell significantly (P0·05) from pre-transplantation levels. The levels of pneumococcal antibodies in the patients before immunization were markedly lower than those in control children of comparable age, for antibodies of IgM, IgG, IgG1 and IgG2 classes (P= < 0·001 in each case). Apart from IgG2 antibodies, the median response to immunization with Pneumovax II was not significantly different from the controls (P0·05). However, because of the lower pre-immunization levels, the patients did not achieve a high post-immunization-specific antibody titre in any immunoglobulin class or subclass, when compared with normal children. Neither the pre-immunization specific antibody levels nor the response to immunization were affected by splenectomy or the presence of chronic graft-versus-host disease. Immunization of the donor before bone marrow harvest did not influence the level of specific antibody 1 year or more after transplantation. No significant correlation was found between the total serum IgG2, the patients'age at the time of assessment, or time after transplantation, and the IgG2-specific antibody response. The lack of specific antibodies and the poor IgG2 response to pneumococcal antigens may contribute towards the occurrence of infection with Streptococcus pneumoniae in the late post-transplantation period.
Neopterin release from human endothelial cells is triggered by interferon-gamma
Authors: ANDERT S E , GRIESMACHER A , ZUCKERMANN A , MÜLLER M M
Published: July 2010

Human umbilical vein endothelial cells (HUVEC) were investigated for their ability to produce neopterin, a biochemical marker for an activated immune system. Interferon-gamma (IFN-γ), IL-1α, IL-2, IL-6, tumour necrosis factor-alpha, granulocyte/macrophage colony stimulating factor, phytohaemagglutinin and concanavalin A were used to stimulate HUVEC. While IFN-γ induced neopterin release from HUVEC in a time- and dose-dependent manner, all the other cytokines used had no effect on neopterin production. High neopterin levels are found in patients with rejection episodes or infections. Our results suggest that not only monocytes and macrophages, which are known to synthesize neopterin, but also endothelial cells are responsible for these high serum neopterin levels.
Normal C3b receptor (CR1) genomic polymorphism in patients with insulin-dependent diabetes mellitus (IDDM): is the low erythrocyte CR1 expression an acquired phenomenon?
Authors: RUUSKA P E , IKÄHEIMO I , SILVENNOINEN-KASSINEN S , KÄÄR M-L , TIILIKAINEN A
Published: July 2010

Expression of the erythrocyte complement receptor (C3bR = CR1 = CD35) and its genomic polymorphism (HindIII RFLP) was studied in a group of 80 patients with IDDM, 31 healthy siblings and 101 healthy blood donors. Defective CR1 expression was found in 26% of the patients with IDDM compared with 9% of the controls (P<0.05) and 0% of the siblings. The CR1 gene polymorphism of the IDDM patients did not significantly differ from that of the controls. The presence of a 6.9 kb (L) CR1 gene fragment was associated with a low CR1 expression in the patients (P <0.05) and especially in the controls (P < 0.001). No significant association was found between the presence or absence of the HLA risk antigens for IDDM and CR1 expression. The results confirm that erythrocyte CR1 expression is genetically determined, but the CR1 deficiency associated with IDDM seems to be an acquired rather than a genetic phenomenon.
Reassessment of the relative prevalences of antibodies to gastric parietal cell and to intrinsic factor in patients with pernicious anaemia: influence of patient age and race
Authors: CARMEL R
Published: July 2010

Anti-parietal cell antibody has been reported in nearly all patients with pernicious anaemia in past studies, in contrast with anti-intrinsic factor (IF) antibody which occurs in only 50–70% of such patients. However, observations in the more diverse patient population at our hospital suggest that these prevalences, originally described in predominantly elderly, white patients of European origin, no longer apply. Anti-IF antibody was found in 70% of the 324 patients, with blacks (84%) and Latin Americans (69%) having a significantly higher prevalence than whites (55%). In contrast, only 55% of the 266 patients tested had anti-parietal cell antibody. It was noteworthy that this low rate was similar in all racial groups. However, patients lacking anti-parietal cell antibody were significantly younger than those who had the antibody (54.8±17.8 vs 59.6±16.2 years, P=0.022). Overall, a striking 30% of all patients had anti-IF antibody but not anti-parietal cell antibody, while only 13% had the latter antibody without having anti-IF antibody. This pattern was particularly striking among black patients. An interesting incidental observation was that gastrin levels were not associated with antibody status, but were significantly higher not only among women than among men but also among white and black patients than among Latin-American patients. The findings show that anti-parietal cell antibody is not found nearly as often in pernicious anaemia as has been reported in the past, and thus has no value as a diagnostic tool in pernicious anaemia. They also suggest clues to different expressions of pernicious anaemia or of its immunologic response, particularly among younger patients with the disease.
T lymphocyte anergy during acute infectious mononucleosis is restricted to the clonotypic receptor activation pathway
Authors: PÉREZ-BLAS M , REGUEIRO J R , RUIZ-CONTRERAS J , ARNAIZ-VILLENA A
Published: July 2010

The transient T cell anergy associated with acute infectious mononucleosis (IM) caused by the Epstein Barr virus has been analysed in a sample of 14 IM children. Peripheral blood mononuclear cells (PBMC) obtained from IM patients showed a significant specific impairment in their proliferative response to both phytohaemagglutinin (PHA; P <0.05) and to an anti-CD3 MoAb (P <0.001), although both responses reached normal control levels by addition of a submitogenic dose of either phorbol myristate acetate (PMA) or recombinant IL-2 (rIL-2). In contrast, activation signals delivered through other surface molecules (CD2, CD28) or other transmembrane pathways (PMA plus a calcium ionophore) elicited normal or high proliferative responses in most IM PBMC. In a group of live patients tested, the synthesis of IL-2 by IM PBMC in the presence of PMA was impaired when PHA or anti-CD3 was used as stimulus, but it reached normal levels with anti-CD2 or ionophore. Lastly, PHA failed to induce IL-2α receptor (IL-2Rα) expression in IM PBMC from four tested patients, but the presence of PMA completely corrected this defect. Taken together, these results strongly suggest that the T cell anergy associated with acute IM is due lo a T cell receptor (TCR)-specific impairment in the induction of genes involved in T cell proliferation (including those coding for IL -2 and IL-2R5α) upon membrane signalling to otherwise normal T lymphocytes, since CD2, CD28 and certain transmembrane activation pathways are uncoupled from CD3 in these particular pathological conditions (and perhaps in most in vivo situations). This and other similar experimental approaches to transient secondary immunodeficiencies may help to unravel the physiopathological role of different surface molecules in T cell activation.
The defect seen in the phosphatidylinositol hydrolysis pathway in HIV-infected lymphocytes and lymphoblastoid cells is due to inhibition of the inositol 1,4,5-trisphosphate 1,3,4,5-tetrakisphosphate 5-phosphomonoesterase
Authors: NYE K E , RILEY G A , PINCHING A J
Published: July 2010

Lymphocytes infected in vivo with HIV or lymphoblastoid cells exposed in vitro to either HIV or its envelope glycoprotein (gp120) show a defect in inositol polyphosphate-mediated signal transduction together with an associated abnormality in intracellular calcium regulation. The defect in patients reverses after treatment with the anti-retroviral agent zidovudine (AZT). We present evidence that the defect is at the level of the lns (1,3,4,5)P4 5-phosphomonoesterase (PME) in these cells and that, though elevation of the intracellular ATP level partially down-regulates the activity of this enzyme. such changes alone are unable to account for the complete inhibition seen in HIV-infected cells.
Monocyte cytokine secretion induced by chemically-defined derivatives ofKlebsiella pneumoniae
Authors: HMAMA Z , LINA G , VINCENT C , WIJDENES J , NORMIER G , BINZ H , REVILLARD J P
Published: July 2010

The capacity of a K. pneumoniae membrane proteoglycan (Kp-MPG) and four of its chemically defined derivatives to activate human monocytes was studied by measuring immunoreactive IL-1β, IL-6 and tumour necrosis factor-alpha (TNF-α) in culture supernatants. Monocyte culture supernatants were also tested for their comitogenic activity on concanavalin A-stimulated thymocytes and for their cytotoxic activity on the mouse fibroblastic L929 cell line. The four Kp-MPG derivatives were: (i) an acylpoly(1-3)galactoside (APG); (ii) an APG preparation submitted to acid hydrolysis which removed all fatty acids but left intact the galactose chain of APG (GC-APG); (iii) a preparation obtained by mild alkaline hydrolysis, containing additional ester-linked C14 and C16 fatty acids bound to the APG molecule (EFA-APG); and (iv) a polymer of the latter compound (APG pol). Kp-MPG induced the synthesis of IL-1β. IL-6 and TNF-α with dose-responses and kinetics similar to those of Salmonella minnesota lipopolysaccharide (Sm-Re-LPS). APG pol and EFA-APG induced the secretion of the three cytokines with lower potency than Kp-MPG or Sm-Re-LPS. APG did not trigger any detectable cytokine production and GC-APG induced only borderline and inconsistent responses. Our data demonstrate the critical role of ester-linked C14 and C16 fatty acids in the triggering of monocyte response to Kp-MPG derivatives.
Relationship between IL-2 receptor expression and proliferative responses in lymphocytes from HIV-1 seropositive homosexual men
Authors: CHOPRA R K , RAJ N B K , SCALLY J P , DONNENBERG A D , ADLER W H , SAAH A J , MARGOLICK J B
Published: July 2010

Previous studies have shown that exogenous IL-2 does not correct the reduction in phytohaemagglu-tinin (PHA)-induced proliferation of lymphocytes from HIV-1 infected (HIV+) individuals. We investigated the mechanism of this reduction to determine if reduced expression of the complete IL-2 receptor (IL-2R) was responsible. In a series of experiments, PHA-stimulated lymphocytes from a total of 89 HIV− and 93 HIV+ homosexual men from the Baltimore Multicentre AIDS Cohort Study (MACS) were studied to determine the expression of messages for the α and β subunits of the IL-2R, the binding of 125I-IL-2 to high affinity IL-2R, and the effect of IL-2 on cell proliferation. Compared to HIV− donors, PHA-stimulated lymphocytes from most HIV+ donors demonstrated (i) a reduction in high affinity IL-2R expression that correlated with the reduction in the IL-2-induced proliferative response; and (ii) a reduction in expression of both IL-2R α- and β-chain mRNA which may be responsible for decreased high affinity IL-2R expression. However, lymphocytes from some HIV+ individuals had borderline low IL-2-induced proliferation despite normal or elevated expression of high affinity IL-2R. These results suggest that decreased expression of IL-2R may account, at least in part, for the lower proliferative response of cells from HIV+ donors.
Immunoglobulin G subclass responses to mycobacterial lipoarabinomannan in HIV-infected and non-infected patients with tuberculosis
Authors: DA COSTA C T K A , KHANOLKAR-YOUNG S , ELLIOTT A M , WASUNNA K M A , McADAM K P W J
Published: July 2010

Immunoglohulin G subclass responses to lipoarabinomannan (LAM) of Mycobacterium tuberculosis were determined by ELISA in both HIV-1 antibody positive (n=31) and negative (n=43) patients with tuberculosis (TB), Responses were also studied in a group of healthy controls (n= 16) and HIV-1 antibody positive (n=60) individuals without TB. IgG2 antibodies were the predominant subclass, being present in 25 of 43 non-HIV-infected TB patients (58%) and in 11 of 31 HIV-infected TB patients (35%). However. HIV+ TB patients also showed IgG4 (n= 16; 52%). and IgG1 (n=4, 13%) responses to LAM. whereas these subclasses were absent in sera from HIV TB patients. Individuals in both non-tuberculous control groups showed no antibody responses to LAM. The influence of HIV infection on B cell responses to LAM, and possible mechanisms for antibody-mediated regulation of immunity to TB, are explored.