bluuebunny/crossref_metadata_2025 huggingface dataset:
Inhibition of cellular activation of retroviral replication by CD8+ T cells derived from non-human primates
Authors: POWELL J D , BEDNARIK D P , FOLKS T M , JEHUDA-COHEN T , VILLINGER F , SELL K W , ANSARI A A
Published: July 2010

To test the hypothesis that CD8+ T cells inhibit viral replication at the level of cellular activation, an Epstein-Barr virus (EBV)-transformed cell line (FEcl) from a simian immunodeficiency virus (SIV)-seropositive sooty mangabey monkey was transfected with a human CD4 gene and shown to be replication-competent for HIV-1, HIV-2 and SIV. Utilizing a dual-chamber culture system, it was found that inhibition of viral replication can be mediated by a soluble factor. The FEcl cell line was transiently transfected with an LTR-driven CAT reporter gene. It was found that autologous CD8+ T cells markedly inhibited CAT activity. Furthermore, co-transfection of the FEcl cell line with an LTR-driven tat plasmid and LTR-CAT was able to quantitatively mitigate the suppressive effect. Thus, this inhibition appears to be directed at cellular mechanisms of viral transcription. Control transfections with an LTR-driven CAT plasmid with a mutation at the NFkB binding site yielded no CAT activity, suggesting that most viral replication as measured by CAT activity is dependent, to a large extent, upon cellularly derived NFkB binding proteins.
Soluble pIasma IL-2 receptors and maIaria
Authors: RILEY E M , ROWE P , ALLEN S J , GREENWOOD B M
Published: July 2010

PIasma levels of soluble IL-2 receptor (sIL-2R) were measured by immunoassay in 180 individuals, aged 1–70 years, living in a maIaria-endemic community in West Africa. slL-2R levels were compared with age. maIaria parasitacmia. maIaria-associated morbidity and cellular immune responses to PIasmodium falciparum antigens. PIasma levels of sIL-2R were independently associated with both age and patent maIaria parasitacmia. No significant association was observed between IL-2R levels and concurrent maIaria morbidity (i.e. Fever associated with maIaria), but the number of individuals with clinical maIaria at the time of sampling was small. Although there was no association between pIasma sIL-2R levels and in vitro proliferativc responses of peripheral blood mononuclear cells (PBMC) to a number of defined maIaria antigens, we did find a significant negative association between sIL-2R and in vitro proliferation of unslimulatcd PBMC. High levels of sIL-2R (up to 5500 U ml) were detected in the pIasma of maIaria-infected individuals: this is indicative of a vigorous cellular immune response to malaria antigens in vivo and does not support the notion that maIaria infections are generally immunosuppressive. Indeed, we found that, at the low levels of parasitacmia present in study subjects, there was no significant difference in the mean prolifcrative response to maIaria antigens in infected subjects when compared with uninfected subjects.
Primary structure of a variable region of the VκI subgroup (ISE) in light chain deposition disease
Authors: ROCCA A , KHAMLICHI A A , AUCOUTURIER P , NOËL L-H , DENOROY L , PREUD'HOMME J-L , COGNÉ M
Published: July 2010

Although structural abnormalities of monoclonal immunoglobulin light chains (LC) are suspected to play a determinant role in non-amyloid light chain deposition disease (LCDD), this condition is as yet poorly documented at the molecular level, since only three sequences have been reported to date. In a case of myeloma-associated LCDD, the patient's urine contained an unglycosylated κ Bence Jones protein made up of dimers and monomers with an apparent molecular mass of 25000 which was assigned to the VκI subgroup by N-terminal amino acid sequencing. The complete variable region sequence of the monoclonal κ chain produced by the malignant plasma cells was amplified by polymerase chain reaction (PCR) using small amounts of material obtained by bone marrow aspiration. The sequence of three independently amplified cDNA clones derived from a normal-sized κ messenger RNA was identical to that of the urinary κ chain. The κ mRNA had an overall normal structure made up of a VκI sequence rearranged to JκI- Several unusual features of the variable region (the first complete VκI sequence reported in LCDD) included three substitutions that introduced hydrophobic residues at spatially close positions. The strategy associating N-terminal sequence determination and cDNA cloning by PCR could help in accumulating new sequence data and improving our understanding of LCDD pathogenesis.
Renal fibroblasts are sensitive to growth-repressing and matrix-reducing factors from activated lymphocytes
Authors: KITAMURA A , KITAMURA M , NAGASAWA R , MARUYAMA N , MITARAI T , TAKAHASHI T , ISODA K
Published: July 2010

Various forms of nephropathy accompany interstitial fibrosis with lymphocytic infiltration. To probe the relationship between lymphocyte-derived factors and renal fibroblasts, we studied the effect of culture supernatant from lymphocytes stimulated by concanavalin A (ConASN) on the growth and matrix metabolism of rat kidney fibroblasts. 3H-thymidine incorporation and Northern analysis, respectively, revealed that ConASN repressed cell growth and the mRNA level of collagen type l, but dramatically elevated the steady-state expression of metalloproteinase transin/stromelysin. The growth inhibitor in ConASN was moderately heat-sensitive and less than 5 kD in molecular size, qualities that differed from those of transforming growth factor-beta (TGF-β), IL-1β, IL-6, and tumour necrosis factor-alpha (TNF–α)– The matrix regulatory factor in ConASN was highly heat-sensitive and more than 30 kD in size. Among several lymphokines tested. TNF-a produced the same effects as ConASN on the metabolism of extracellular matrix. We hypothesize that lymphocyte-derived factors have a significant role in the attenuation of renal fibrogcnesis, as well as its progression, via inhibiting cell growth and matrix accumulation.
Ontogeny and induction of adhesion molecule expression in human fetal intestine
Authors: DOAN A , MacDONALD T T , SPENCER J
Published: July 2010

In this study we examined the distribution of the adhesion molecules ICAM-1, VCAM-1 and E-selectin in human fetal intestine, to determine whether they may have a role in the development of gut-associated lymphoid tissue. Secondly, we studied the tempo of induction of these molecules after T cell activation in explants of human fetal intestine cultured in vitro. In the fetus from 11 to 20 weeks gestation, endothelial expression of ICAM-1 and diffuse staining of VCAM-1 was observed in the lamina propria. In contrast, there was intense expression of ICAM-1 and VCAM-1 in the developing Peyer's patches, suggesting that these molecules may be involved in the accumulation or organization of lymphoid tissue in the gut. After T cell activation in fetal intestinal explants, the expression of ICAM-1 and VCAM-1 was increased on most endothelial cells, leucocytes, and stromal cells in the lamina propria. Expression was maintained for at least 4 days. In contrast, the induction of E-selectin was rapid, and the expression was transient, despite the continuing presence of activated T cells and macrophages. This suggests that other factors are required to prevent the down-regulation of E-selectin to maintain the sustained expression sometimes observed in vivo.
High circulating leukaemia inhibitory factor (LIF) in patients with giant cell arteritis: independent regulation of LIF and IL-6 under corticosteroid therapy
Authors: LECRON J C , ROBLOT P , CHEVALIER S , MOREL F , ALDERMAN E , GOMBERT J , GASCAN H
Published: July 2010

Leukaemia inhibitory factor (LIF) is a cytokine which possesses a wide range of biological activities including, like IL-6, the capacity to stimulate acute phase protein (APP) synthesis. We have developed a sensitive and specific ELISA for human LIF, and tested the circulating cytokine levels in various disease stales, some of which are associated with inflammation. LIF was detected in 11/20 sera from patients with giant cell arteritis (GCA), a vasculitis syndrome affecting particularly the temporal artery, characterized by panarteritis with inflammatory cell infiltration. LIF levels were considerably elevated in some patients who also displayed elevated levels of IL-6 and C-reactive protein (CRP); however, no correlation was observed between the levels of circulating LIF and levels of IL-6 or CRP. Furthermore, LIF levels were not affected by corticosteroid therapy, whereas IL-6 and CRP decreased rapidly, as clinical symptoms resolved. A putative role for LIF in the persistence of hislological lesions is discussed. This is the first report of the presence of circulating LIF in sera. These results are in agreement with the complexity of induced inflammatory cylokines and corticoid regulation of APP synthesis observed in vitro and in vivo.
CR1 (CD35) and CR3 (CD11b/CD18) mediate infection of human monocytes and monocytic cell lines with complement-opsonized HIV independently of CD4
Authors: THIEBLEMONT N , HAEFFNER-CAVAILLON N , LEDUR A , L'AGE-STEHR J , ZIEGLER-HEITBROCK H W L , KAZATCHKINE M D
Published: July 2010

Peripheral blood and tissue mononuclcar phagocytes serve as major viral reservoirs in HIV-infected individuals. We investigated the role of complement receptors CR1 (CD35) and CR3 (CD11b/CD18) in mediating productive infection with complement-opsonized HIV-1 and HIV-2 of cultured normal human peripheral blood monocytes. the promonocytie cell line THP-l, the monocytic cell line Mono Mac 6 and the glial cell line U251-MG. Cells were infected with the HTLV-IIIB strain of HIV-1 or the LAV-2 strain of HIV-2 that had been preopsonized with fresh human normal HIV seronegative serum. Productive infection was assessed by syncytia formation, the MTT cytotoxicity assay and/or release of p24 antigen in culture supernatants. Using suboptimal amounts of virus to infect the cells, we observed a higher and earlier productive infection of the cells with complement-opsonized HIV than with unopsonized virus. The enhancing effect of complement was totally suppressed by blocking CR1 or CR3 function with F(ab)′2 fragments of anti-receptor MoAbs; while blocking of the LFA-1 antigen had no effect. The infection of monocytic cells with eomplement-opsonized virus occurred independently of CD4 since it was not inhibited by F(ab)′2 fragments of a MoAb against the gp 120 binding site of CD4 and since infection also occurred with Mono Mac 6 and U251-MG cells, which lack expression of the CD4 antigen and of CD4 mRNA. These observations suggest that complement may mediate productive infection of cells of the monocytic lineage with ‘lymphocylotropic’ HIV strains independently of CD4.
Purified human oral mucosal Langerhans cells function as accessory cells in vitro
Authors: BARRETT A W , ROSS D A , GOODACRE J A
Published: July 2010

Oral mucosal Langerhans cells (OMLC) may have an importanl role in the induction of immune responses to oral pathogens. In this study. anti-HLA-DR antibody-coated immunomagnctic beads were used to purity OMLC from suspensions of normal human buccal epithelium and the capacity of the purified cells to function as accessory cells (AC) was investigated. Electron microscopy was used to show that the purified cells possessed all recognized ultrastructural features previously described in epidermal Langerhans cells. Using T lymphocyte proliferation assays in hanging drop microcult ures, it was found that purified OMLC could function as AC for responses to concanavalin A by autologous T cells. Purification of OMLC from small biopsies of oral mucosa has enabled us to show that OMLC, like epidermal Langerhans cells, can function as AC in vitro.
The effects of retinol onin vitroimmunoglobulin synthesis by cord blood and adult peripheral blood mononuclear cells
Authors: WANG W , NAPOLI J L , BALLOW M
Published: July 2010

In this study we examined the effects of retinol (ROH), a metabolic precursor of retinoic acid (RA), on Staphylococcus aureus Cowan I (SAC)-induced immunoglobulin synthesis of cord blood mononuclear cells (CBMC) and adult peripheral blood mononuclear cells (PBMC). ROH augmented SAC-induced IgM synthesis of CBMC by 5·9±1·5-fold (n= 7, mean ± s.d.), and IgG synthesis of adult PBMC by 16·3 ±5·1-fold (n= 3) at optimal concentrations of 10−6 m and 10−11 m, respectively. No augmenting effects could be demonstrated for the other immunoglobulin isotypes. Time-course studies showed that the synthesis of IgM by CBMC was accelerated with detectable immunoglobulin in supernatant fluids starting on day 3. ROH augmented immunoglobulin synthesis of CBMC stimulated by Epstein-Barr virus (EBV), a T cell-independent polyclonal activator, and of EBV-transformed B cell clones (2·5 ± 0·2 and 41 ± 1·5-fold increase, respectively), which suggests that ROH can act directly on B cells to enhance immunoglobulin synthesis. In contrast, when ROH was preincubated with cord blood T cells, washed and added to the B cell-enriched fraction with SAC, no increase (0·9–1·8-fold) in IgM synthesis was obtained. Thus, the principal mechanism(s) by which ROH augments immunoglobulin synthesis is by acting on B cells. This is in contrast to the immunoglobulin-enhancing effects of RA which is mediated by T cells, or T cell products, e.g. cytokine. Our studies suggest that RA and ROH may have different pathways of immunoglobulinenhancing effects, perhaps mediated by different retinoid binding proteins resulting in gene activation and immunoglobulin synthesis.
Peri-operative modulation of cellular immunity in patients with colorectal cancer
Authors: NICHOLS P H , RAMSDEN C W , WARD U , TREJDOSIEWICZ L K , AMBROSE N S , PRIMROSE J N
Published: July 2010

The peri-operalive cellular immune response is depressed in patients with gastrointestinal cancer, a factor which may facilitate maligtiant dissemination. We have investigated the effects of perioperative rIL-2 and a combination of rlL-2 and interferon-alpha (IFN-α) on both peripheral blood lymphocyte function and number in patients undergoing surgical resection for colorectal cancer. Fifty-two patients were randomly allocated to either control, rIL-2 or rIL-2 with IFN-α treatment arms. In vitro studies were performed pre-operatively and on post-operative days I, 4, 7 and 10. Natural ikller (NK) and lymphokine-activated killer (LAK) cell function were profoundly depressed in control patients (P < 0·001; P < 0·001), an effect abrogated in both treatment groups; indeed NK function was augmented in the rIL-2 and IFN-α group on the first post-operative day in association with an increase in the percentage of cells expressing CD16 and CD56 (P < 0.01). Flow cytometric analysis of lymphocyte subsets in the control group was unremarkable, except for an early post-operative fall in numbers of lymphocytes. Treatment with either rIL-2 or rIL-2 and IFN-α produced an initial profound reduction in T lymphocyte numbers, followed by a ‘rebound’ lymphocytosis of activated CD3+ T cells, as demonstrated by a significant increase in co-expression of CD25, CD38, and CD45RO. No significant differences were observed between either of the treatment groups. Adjuvant immunotherapy affects peri-operative anti-tumour immune responses, and this may influence long term outcome in patients undergoing surgery for gastrointestinal cancer.
Up-regulation of alveolar macrophage platelet-derived growth factor-B (PDGF-B) mRNA by interferon-gamma fromMycobacterium tuberculosisantigen (PPD)-stimulated lymphocytes
Authors: WANGOO A , TAYLOR I K , HAYNES A R , SHAW R J
Published: July 2010

Macrophage production of PDGF-B is believed to be important in the pathogenesis of diseases where chronic lung inflammation develops into fibrosis. Since tuberculosis is characterized by chronic inflammation and tissue fibrosis, we asked if lymphokincs from lymphocytes stimulated by the Mycobacterium tuberculosis antigen PPD, contained factors capable of increasing human alveolar macrophage PDGF-B mRNA. Supernatants from both phytohaemagglutinin (PHA)- and purified protein derivative (PPD)-stimulated lymphocytes, when added lo macrophages. induced an increase in the mRNA of PDGF-B, but not transforming growth factor-beta (TGF-β). When lymphocytes from contacts of patients with tuberculosis, patients with tuberculosis, and normal subjects were compared following PPD stimulation, the lymphocytes from the contacts had the greatest proliferation response, the greatest production of inierferon-gamma (IFN-γ), and their lymphokincs induced the greatest increase in PDGF-B mRNA in macrophages. Recombinant human IFN-γ reproduced this ability of lymphokines to increase macrophage PDGF-B mRNA. Finally, the increase in macrophage PDGF-B mRNA following incubation with supernatants from PPD-stimulated lymphocytes was shown to be due to IFN-γ, when the increase in macrophage PDGF-B mRNA was prevented by addition of anti-human IFN-γ antibody to the lymphocyte supernatant This study indicated that antigen-stimulated lymphocytes released IFN-γ. which in turn resulted in an increase in PDGF-B mRNA in alveolar macrophages. Such a mechanism provides a link between the DTH response and the first stages of a fibrotic reaction, and may offer an explanation for the progression of chronic inflammation lo fibrosis, as occurs in the lungs of patients with untreated pulmonary tuberculosis.
Seroreactivity with thePlasmodium falciparumblood stage antigen Pf332 in adults and children from malaria-endemic regions
Authors: IQBAL J , PERLMANN P , GREENWOOD B M , BERZINS K
Published: July 2010

It has earlier heen reported that the human monoclonal antibody (MoAb 33G2) and polyclonal antibodies reactive with Pf332 may interfere in vitro with the erythrocytic cycle of Plasmodium falciparum at two potential target sites for protective antibodies, indicating that the antigen may constitute an important target for immune responses during malaria infections, MoAb 33G2 shows its highest reactivity with repeated sequences in the antigen Pf332 and also cross-reacts with determinants in Pf155/RESA. This study was conducted in order to assess the prevalence of seroreactivity against Pf332 in individuals residing in areas of different malaria endemicity, and in children with different degrees of disease severity. We now report that individuals resident in malaria-endemic regions show a high prevalence of seroreactivity to antigen Pf332 repeat sequences. The mean antibody concentrations were significantly higher in donors from Liberia, Madagascar and Gambia compared with Thai and Colombian donors, probably reflecting the higher degree of exposure in the African regions. Although the levels of such antibodies in individual sera correlated well with the levels of antibodies to one Pf155/RESA repeat peptide, only a minor part of the peptidereactive antibodies were cross-reactive between the two antigens. In Gambian children, the mean concentrations of antibodies reactive with Pf332 or Pf155/RESA peptides were significantly higher in children with severe than with mild malaria. Further longitudinal studies are needed to evaluate the capacity of Pf332 to induce potentially protective or harmful antibody responses.
Experimental murine paracoccidioidomycosis: relationship among the dissemination of the infection, humoral and cellular immune responses
Authors: SINGER-VERMES L M , CALDEIRA C B , BURGER E , CALICH V L G
Published: July 2010

The dissemination of Paracoccidioides brasiliensis cells to the heart, omentum/pancreas, spleen, liver and lungs, assessed by colony forming unit (CFU) counts, the levels of specific antibodies to this fungal agent (by ELISA), and the specific DTH reaction were studied in susceptible (B10.A) and resistant (A/Sn) mice. The animals were infected intraperitoneally with P. brasiliensis yeast cells and were evaluated 2, 4, 12 and 16 weeks later. The mosl remarkable differences between the two mouse strains were observed 16 weeks after infection, when B10.A mice displayed high numbers of CFU in all examined organs, except the heart, high antibody titres, and depressed DTH response. At this point. A/Sn mice presented low or absent CFU in all organs, low antibody litres and expressive DTH response. The CFU counts were shown to be a reliable parameter to discriminate susceptible from resistant animals. The fungal load in the most affected organs correlated wilh the antibody litres and was inversely correlated with the intensity of the DTH reaction. The patterns of immune response in this model mimic human paracoccidioidomycosis, in which high specific antibody levels and depressed DTH reactions are found in multifocal and severe forms of the disease.
Ascarisreinfection of slum children: relation with the IgE response
Authors: HAGEL I , LYNCH N R , DI PRISCO M C , ROJAS E , PÉREZ M , ALVAREZ N
Published: July 2010

Total and Ascaris-specific serum IgE levels were measured in a group of 98 Ascaris-infected children from a slum area of Caracas. Venezuela, in whom the infections were eliminated by regular treatment for 22 months with the anthelmint Oxantel/ Pyrantel (‘Quanlrel’). The children were re-evalualed at the end of the treatment programme, and then 8 months later, at which time reinfection was assessed. Total IgE levels at the beginning of the study were significantly higher in the children who became reinfected after treatment. compared with those who did not. The anthelmint treatment caused a significant decrease in the tolal IgE levels in most of the children, and after a period of 8 months without treatment these continued to decrease in the non-reinfected group, but increased again in the reinfected children. The reverse pattern was found for Ascaris-specific IgE antibody levels, and in fact an inverse correlation was found between total and anti-Ascaris IgE levels. Striking associations were found between reinfection and high pretreatment values of total IgE, but low levels of specific IgE antibody. These data support the concept that specific IgE antibody may participate in the protection against helminthic infection, and suggest that the polyclonal stimulation of IgE synthesis caused by these parasites may reduce the effectiveness of such responses. The results also indicate that different individuals have varying propensities to respond polyclonally to the helminths, and this influences their resistance to infection.
Duodenal intraepithelial γ/δ T cells and soluble CD8, neopterin, and β2-microglobulin in serum of IgA-deficient subjects with or without IgG subclass deficiency
Authors: NILSSEN D E , AUKRUST P , FRØLAND S S , MÜLLER F , FAUSA O , HALSTENSEN T S , BRANDTZAEG P
Published: July 2010

Expression of the γ/δ T cell receptor (TCR) on CD3+ intracpithclial lymphocytes (IELs) was studied by two-colour immunofluorescence in duodenal tissue sections from healthy (n= 6) or infection-prone (n = 7) subjects with selective IgA deficiency (IgAD), and subjects (n = 4) with combined IgAD and IgG subclass deficiency. TCRγ/δ+ IEL proportions in selective IgAD subjects (median 6·3%, range 1·0–41%) and in those with combined deficiency (median 4·5%, range 1±2·33%) were well within the range (0·3–38%) for histologically normal controls (n= 11), but the healthy IgAD subgroup tended to show raised TCRγ/δ+ IEL proportions (median 13·6%) compared with the other two subgroups. Also the number of TCRγ/δ+ IELs per intestinal length unit was relatively high (median 13·9/mm) in the healthy IgAD subjects, and significantly raised (P < 0·03) compared with controls (median 3·2/mm). Paired staining revealed that most TCRγ/δ+ IELs in both selective IgAD (98%) and combined deficiency (99%) were CD8, and a large fraction (median 84% and 63%, respectively) expressed the Vδ1/Jδ1-encoded epitope. The total number of CD3’ IELs (mostly CD8+) was similar to controls. IgAD subjects, and especially the healthy subgroup, had significantly increased serum concentrations of soluble CD8 (P < 0·0002), neopterin (P < 0·005), and β2-microglobulin (P < 0·007). which was similar to our previous observations in common variable immunodeficiency, and probably reflected stimulation of cell-mediated immunity. In addition, the increased TCRγ/δ+ IELs might reflect a component of compensatory surface protection in the healthy IgAD subgroup.
Mannan-binding protein—levels in plasma and upper-airways secretions and frequency of genotypes in children with recurrence of otitis media
Authors: GARRED P , BRYGGE K , SØRENSEN C H , MADSEN H O , THIEL S , SVEJGAARD A
Published: July 2010

We have investigated a possible association between recurrence of olitis media and low concentrations of mannan-binding protein (MBP) in plasma and upper-airway secretions. The protein concentration was measured in plasma (n= 76), nasopharyngeal secretions (n= 83) and middle ear effusions (n= 73) from otitis-prone children, children with less recurrence of acute otitis media, children with no previous history of acute otitis media, but suffering from secretory olitis media, and healthy children. Moreover, genetic polymorphisms associated with low MBP plasma levels were investigated in DNA from nasopharyngeal tonsils of 89 children with recurrence of otitis media. A wide range of M BP plasma concentrations was found. No statistically significant differences in M BP plasma concentration were observed between patients and controls. Nor was there any increased frequency of the genotypes associated with low MBP plasma concentrations. Thus, our results do not support the assumption that low concentration and/or MBP deficiency alone predispose to recurrence of otitis media in Caucasian children. MBP was detected in both nasopharyngeal secretions (1/175 of plasma level) and middle ear effusions (1/4 of plasma level), suggesting a role for the protein in the local mucosal immune defence system at these locations. In contrast. MBP was undetectable in 53 samples of mixed-saliva.
Modulation of adhesion molecule expression on endothelial cells during the late asthmatic reaction: role of macrophage-derived tumour necrosis factor-alpha
Authors: LASSALLE P , GOSSET P , DELNESTE Y , TSICOPOULOS A , CAPRON A , JOSEPH M , TONNEL A B
Published: July 2010

In a previous work we have demonstrated that in patients exhibiting a late allergic reaction (LAR), alveolar macrophages (AM) collected 18 h after bronchial allergen challenge produced high levels of IL-6 and tumour necrosis factor-alpha (TNF) which is known to up-regulate the endothelial cell expression of adhesion molecules participating in the development of the inflammatory reaction in bronchial asthma. For these reasons, we evaluated the effect of AM supernatants from asthmatic patients developing an LAR on intercellular adhesion molecule-1 (ICAM-1) and endothelial leucocyte adhesion molecule-1 (ELAM-1) expression by human endothelial cells. The expression of adhesion molecules was assessed by an ELISA method and compared with the effect of an optimal dose of human recombinant (hr) TNF. Results showed that AM supernatants, from challenged asthmatics developing an LAR, increased significantly the ICAM-1 and ELAM-l expression on endothelial cells to a level similar Io that obtained in thc presence of hrTNF (500 U/ml)(P<0·001 in both cases, respectively 90·4% and 75·2% of the level obtained with hrTNF). In contrast, AM supernatants from asthmatics at baseline or exhibiting, after challenge, a single early reaction had no significant effect on these parameters (P=NS in both cases, respectively 23·5% and 24·7% of the ICAM-1 expression, 22·7% and 15·3% of the ELAM-1 expression obtained with hrTNF). AM-derived TNF present in these supernatants was thought to play a key role in endothelial cell stimulation, since: (i) TNF concentration in AM supernatants correlated with its effect on ICAM-1 (r= 0·80. P 10−4) and ELAM-1 expression (r = 0·88, P 10–5); and (ii) a neutralizing anti-TNF antibody decreased their effect (68% and 80% respectively on ICAM-1 and ELAM-1 expression). Moreover, the role of IL-6 was excluded on the basis both of the hrIL-6 inefficiency to induce ICAM-1 and ELAM-1 synthesis, even in costimulation with hrTNF, and of anti-IL-6 antibody to neutralize the effect of AM supernatants. Our results suggest that, beside mast cells and lymphocytes, macrophages might participate in the induction of the local inflammatory reaction observed in bronchial asthma. During the LAR, cytokines and especially TNF are able, through an enhanced adhesion molecule expression on endothelial cells, to facilitate the bronchial cellular influx.
T cell epitopes of the major fraction of rye grassLolium perenne (Lol pI) defined using overlapping peptidesin vitroandin vivo. I. Isoallergen clone 1A
Authors: BUNGY POOR FARD G A , LATCHMAN Y , RODDA S , GEYSEN M , ROITT I , BROSTOFF J
Published: July 2010

One hundrcd and fifteen overlapping synthetic peptides spanning the entire sequence of the isoallergen clonelA of Lol p I from rye grass Lolium perenne were synthesized by the multi-pin technique. The peptides were overlapping 12mers, offset by two residues and overlapping by 10 residues. Sets of six adjacent overlapping peptides (except pool-1,15,20) were pooled and were used in vitro and in vivo to map the T cell epilopes on Lol p I. Six atopics who were skin test and RAST positive to rye grass showed T cell responses to L. perenne extract (LPE) and its major fraction (Lol p I). Five out of six showed T cell responses in vitro to peptide pool-17, while five non-atopics did not respond to any of the peptide pools. By testing the individual peptides of pool-17, we have located the T cell epitope on Lol p I. Interestingly, when we tested pool-17 and its single peptides in vivo by intradermal skin testing we found in one patient a typical DTH after 24–48 h to pool-17 and its peptides (peptides 3 and 4) which exactly matched the in vitro responses. By defining the T cell epitopes in this way a greater understanding of the allergic response to pollen will be obtained, and a more effective and less dangerous vaccine may be possible for treating patients with hay fever.
Analysis of cytokine profiles in synovial T cell clones from chlamydial reactive arthritis patients: predominance of the Th1 subset
Authors: SIMON A K , SEIPELT E , WU P , WENZEL B , BRAUN J , SIEPER J
Published: July 2010

Subpopulations of human T cells (Th0, Th1 and Th2) can be distinguished by their cytokine-sceretion pattern. Evidence is increasing from other studies that the outcome of a human disease may depend on the subpopulation of T cells that predominates at the site of inflammation. Reactive arthritis serves as a useful model of chronic inflammatory diseases, because the triggering antigen can be identified. Using this triggering antigen we raised 33 Tcell clones reactive with Chlamydia trachomatis and 25 T cell clones that were not reactive, all from the synovial fluid of two patients suffering from Ohlamydia-induced arthritis. Their cylokine secretion patterns for inlcrferon-gamma (IFN-γ), IL-2 and IL-4 were analysed, as also were mRNAs for IFN-γ and IL-10 by in situ hybridization. Out of the 33 antigen-reactive clones 23 showed a Th1 pattern with IFN-γ but not IL-4 secretion, while the remaining 10 exhibited a ThO pattern. The clones that did not react with Chlaniydia expressed all patterns of cytokine secretion, including a Th2 pattern, thus providing a control population that excludes bias in the sampling procedure. CD4 and CD8 clones displayed a similar cytokine-secretion pattern. In addition this study demonstrates for the first time the expression of IL-10 mRNA in Tcell clones derived from synovial fluid, and ihis was not confined to the Th2 subset. The Th1 response that Chlamydia provoke can be regarded as appropriate for such an obligate intracellular pathogen.
Remission of experimental autoimmune hepatitis is associated with antigen-specific and non-specific immunosuppression
Authors: LOHSE A W , MEYER zum BÜSCHENFELDE K-H
Published: July 2010

Experimental autoimmune hepatitis (EAH) is an animal model for autoimmune hepatitis. The disease is T cell-mediated and runs a subacute course, with maximal disease activity around week four after disease induction and a slow ensuing recovery. The aim of the present study was to investigate the immunoregulatory mechanisms that may account for recovery in EAH. It was found that T cell reactivity to liver antigens preceded histological disease, but at the peak of disease activity this T cell response was already suppressed. Active and antigen-specific suppression could be demonstrated, as irradiated splenocytes from animals at the beginning of recovery from EAH were able to suppress in vitro the T cell response to liver antigens by 42%. The response to an irrelevant antigen was suppressed by 16%, showing additional antigen non-specific suppression in vitro. The response to an in vivo immunization with an unrelated microbial antigen (tetanus toxoid) at the peak of disease was markedly reduced (by 90%). These data demonstrate in vitro and in vivo immunosuppression associated with the overcoming of and recovery from EAH. They stress the importance of immunoregulatory cycles in the control of autoimmune hepatitis.
Genetic analysis of the variable region genes encoding a monospecific human natural anti-DNA antibody
Authors: DALEY M D , MISENER V , OLEE T , CHEN P P , SIMINOVITCH K A
Published: July 2010

Recent evidence suggests that natural autoantibodies may play an integral rote in the development of the normal immune repertoire. To explore the genetic origins of these antibodies, we have isolated and sequenced the variable (V) region genes encoding both the heavy (H) and light (L) chains of a natural anti-DNA antibody, Kim It.4. The genes appear to be derived from the VH4.t8 (subgroup VHIV), JH5, Hum ILI (subgroup VλI) and Jλ3 germline genes. The origin of the H chain diversity gene is more obscure, being potentially derived from one or more of several germline genes, arranged in either the forward or reverse orientations. Both the Kim 11.4 VH and VL genes share significant degrees of similarity with those utilized in other autoantibodies, indicating that at least some degree of V restriction may exist in human autoreactive B cells. The pattern of nucleotide differences between the Kim 11.4 VH and VL genes and their putative germline counterparts suggests that the Kim 11.4 genes may have undergone somatic mutation and arisen as a result of antigen selection.
Expression of anticardiolipin cofactor, human β2-glycoprotein I, by a recombinant baculovirus/insect cell system
Authors: IGARASHI M , MATSUURA E , IGARASHI Y , NAGAE H , MATSUURA Y , ICHIKAWA K , YASUDA T , VOELKER D R , KOIKE T
Published: July 2010

A full-length cDNA coding a human β2-glycoprotein I (β2-GPI) was introduced into the baculovirus genome to construct a recombinant baculovirus. Spodoptera frugiperda (Sf9) cells were infected with the recombinant baculovirus. A protein (mol. wt 43000) reactive with anti-β2-GPI antisera was produced in the insect cells and secreted into the culture medium. The recombinant β2-GPI was purified from the culture supernatant by sequential cardiolipin (CL)-affinity column chromatography and gel filtration. The N-terminal amino acid sequence of the protein was identical to that of the native β2:-GPI purified from human sera, and a putative signal peptide was cleaved from the secreted form of the recombinant protein. The purified recombinant protein had a cofactor activity which enhances CL binding of anticardiolipin antibodies (aCL) in systemic lupus erythematosus (SLE) patients, as well as the native β2-GPI. Thus, the β2-GPI expressed in insect cells is an immunologically active cofactor.
Molecular mechanisms resulting in pathogenic anti-mouse erythrocyte antibodies in New Zealand black mice
Authors: SCOTT B B , SADIGH S , STOW M , MAGEED R A K , ANDREW E M , MAINI R N
Published: July 2010

The New Zealand black (NZB) mouse strain is genetically predisposed to develop, at approximately 6 months of age, a spontaneous and severe autoimmune anaemia caused by production of pathogenic anti-mouse erythrocyte autoantibodies. In order to investigate the molecular mechanisms which lead to anti-mouse erythrocyte autoantibody production we have generated eight anti-mouse erythrocyte MoAbs producing hybridomas from splenocytes of 9- and 12-month-old NZB with spontaneous autoimmune anaemia. IgG2a was the predominant isotype, while IgM, IgG1 and IgG2b were each produced by one hybridoma cell line. All anti-mouse erythrocyte MoAbs were characterized for their antigen specificities. None of the MoAbs cross-reacted with ss- or dsDNA or with other species' erythrocytes, with the exception of one MoAb which cross-reacted with rat erythrocytes. None of the eight hybridomas was demonstrated to express surface or cytoplasmic CD5, suggesting that they derived from CD5- B lymphocytes. All hybridomas when implanted intraperitoneally into BALB/c mice caused anaemia. In order to define the genetic basis and investigate the molecular mechanisms resulting in pathogenic anti-mouse erythrocyte autoantibody production, the pattern of immunoglobulin variable region gene use has been studied. Five of the eight MoAbs whose IgVH genes were sequenced all have functionally rearranged genes from the VH J558 gene family. There is evidence for somatic point mutations in the complementarity-determining regions (CDR) of the IgVH genes in all of these five MoAbs when compared with the closest known germline gene. We suggest that these nucleotide sequence changes are likely to reflect selection by an antigen-driven mechanism. Furthermore, the data indicate that pathogenic anti-mouse erythrocytes are not derived from ‘natural’ autoantibodies.
Antibody-dependent cellular cytotoxicity and neutralizing activity in sera of HIV-1-infected mothers and their children
Authors: BROLIDEN K , SIEVERS E , TOVO P A , MOSCHESE V , SCARLATTI G , BROLIDEN P A , FUNDARO C , ROSSI P
Published: July 2010

The prognostic and protective role of antibodies mediating cellular cytotoxicity (ADCC) and neutralization was evaluated in sera of HIV-1-infected mothers and their consecutively followed children. The presence and titres of ADCC mediating and/or neutralizing antibodies in maternal sera did not predict HIV-1 infection in their respective children. No significant difference in the sera from the children was seen when comparing the presence of neutralizing antibodies between the uninfected and infected children. Stratification of the infected group according to clinical status revealed differences. Only one of 24 AIDS patients had a high neutralizing titre against IIIB. Four patients had a very low titre and the remaining had no detectable neutralizing antibodies at all. In contrast, 10/17 infected non-AIDS children had neutralizing antibodies. Similarly, no significant difference was seen when comparing the presence of ADCC-mediating antibodies between the uninfected and the infected group of children. However, a significantly higher frequency of ADCC was seen in the seropositive non-AIDS children compared with the AIDS children. This study clearly shows that the presence of antibodies mediating ADCC and neutralization in infected children, 0–2 years old, is associated with a better clinical status and delayed disease progression.
Programmed cell death (apoptosis) as a mechanism of cell death in peripheral blood mononuclear cells from cats infected with feline immunodeficiency virus (FIV)
Authors: BISHOP S A , GRUFFYDD-JONES T J , HARBOUR D A , STOKES C R
Published: July 2010

FIV is a lentivirus infection of cats which induces an immunodeficiency syndrome associated with curly qualitative defects in antigen-specific T cell function and with late quantitative detects in CD4+ T lymphocytes. We have observed that peripheral blood mononuclear cells (PBMC) from FIV-infected cats have impaired survival in culture. The mechanism of this in vitro dysfunction and depletion is not known. We have proposed that inappropriate induction of programmed cell death (apoptosis) could account for these in vitro defects. Here, we report that PBMC from FIV-infected eats, with impaired T cell blastogenesis and impaired survival in vitro, undergo an active cell death upon culture, which has the morphological and biochemical characteristics of programmed cell death (PCD). Apoptosis occurred in all six asymptomatic FIV-infected cats, and in none of the nine uninfected cats, which were studied. Changes in cell morphology under both light and electron microscopy, and fragmentation of genomic DNA were characteristic for apoptosing cells. Cell death was spontaneous and occurred in the absence of any stimuli, and culture with the T cell mitogen, concanavalin A (Con A), did not significantly enhance cell death. Activation-induced cell death was inhibited, in a dose-dependent, manner, by addition to the incubation medium of zinc, which has been shown to inhibit the action of endonuclease responsible for the characteristic fragmentation of DNA. Since apoptosis has recently been implicated in AIDS pathogenesis, FIV infection may prove useful to study this aspect of retroviral, in particular HIV, infection.
Comparative effects ofMycobacterium aviumglycopeptidolipid and lipopeptide fragment on the function and ultrastructure of mononuclear cells
Authors: POURSHAFIE M , AYUB Q , BARROW W W
Published: July 2010

Among the various lipids associated with the cell envelope of the Mycobacterium avium complex, the species-specific glycopeptidolipids (GPL) are responsible for distinguishing one serovar from another. In a continuing effort to study the immunonodulatory capabilities of these mycobacterial lipids, we have examined and compared the effects of the GPL and its lipopeptide fragment (β-lipid) on mononuclear cell function. It was observed that the lymphoproliferative response of murine splenic mononuclear cells to mitogen stimulation was reduced by both the GPL and its lipopeptide fragment. Although the responsiveness appeared to be down-regulated to a greater degree by the β-lipid, treatment with either GPL or β-lipid resulted in the release of soluble factors from peritoneal macrophages that caused suppression of the lymphoproliferative responsiveness of splenic mononuclear cells. Flow cytometric analysis of peritoneal macrophages revealed that treatment with the β-lipid fragment caused a marked decrease in expression of the C3bi complement receptor. Mac-1, on macrophages, whereas treatment with GPL resulted in a marked increase in the expression of Mac-2 receptor on macrophages. Treatment of peritoneal macrophages with either GPL or β-lipid resulted in the release of tumour necrosis factor (TNF), as determined by an 1929 biological cytotoxicity assay. Perturbation of macrophage membrane ultrastructure by both GPL and β-lipid was confirmed by electron microscopy, and may be a possible explanation for the resulting alterations in mononuclear cell function observed in this study.
Metabolic fate of monovalent and multivalent antibodies of Heymann nephritis following formation of surface immune complexes on glomerular epithelial cells
Authors: SINGH A K , KASINATH B S
Published: July 2010

Heymann nephritis of the rat has several similarities to human idiopathic membranous glomerulonephropathy, and therefore serves as an animal model for study of the human disease. The disease process in the rat is initiated by autoantibodies forming in situ immune deposits on the surface of the glomerular epithelial cell in the lamina rara externa region of the glomerular basement membrane. It is now understood that multispecific antibodies (like anti-gp600) form the nephritogenic deposits which cause proteinuria, while MoAb (like anti-gp300, anti-90 kD and anti-gp70) form only transient deposits which do not give rise 10 proteinuria. The reasons for differences between pathologic effects of mono- and multispecific antibodies are not known. Following characterization of putative antigens of Heymann nephritis by immunofluorescence, immunogold and immunoblot techniques, we have investigated the metabolic handling of a multispecific (anti-600), monospecific antibody (anti-gp70) and a MoAb (anti-gp330) by the cultured glomerular epithelial cell to gain an insight into the mechanism of nephritogenicity of multispecific antibody. Anti-gp600 reacted to multiple antigens in the 330-kD and 70-kD regions; anti-gp70 reacted to only the 70-kD region. Ultrastructurally, all three types of antigens were present on the plasma membrane, concentrated in the microvillar region. The cells were incubated with the antibodies, and clearance of the antibodies from the cells was evaluated. Following binding, all three antibodies were internalized by the cells. However, it was found that monoclonal anti-gp330 MoAb was cleared most rapidly from the cell (t1/2: 5 min), followed by anti-gp70 (t1/2; 30 min). Anti-gp600 was cleared at four times slower rate than anti-gp70(t1/2 2 h) by the cell. While anti-gp330 MoAb and monospecific anti-gp70 antibody were expelled from the cell in 25–32% digested form, the multispecific anti-gp600 was digested to the extent of only 5–8%. No immune complexes were detected in the medium with any of the three antibodies. The shed label was in intact IgG form. It is concluded that multispecific antibodies of Heymann nephritis are nephritogenic because of their slower clearance and digestion and therefore, higher accretion rate on the surface of the glomerular epithelial cell The differential handling of the antibodies by the glomerular epithelial cell offers an explanation for the in vivo differences in the nephritogenicity of these antibodies observed earlier.
Cationic and high affinity serum IgG anti-dsDNA antibodies in active lupus nephritis
Authors: SUENAGA R , ABDOU N I
Published: July 2010

To investigate differences between cationic anti-dsDNA antibodies during active and inactive nephritis, low- and high-affinity IgG anti-dsDNA antibodies were prepared from sera of a lupus patient and compared for their binding affinity, spectrotype, and idiotype expression. The ratio of high-affinity to low-affinity anti-DNA antibodies and the relative avidity of the high-affinity anti-DNA antibodies decreased when active nephritis became inactive. Isoelectric focusing showed that cationic anti-dsDNA populations were present predominantly in the high-affinity fraction during active nephritis and in the low-affinity fraction during inactive nephritis. Idiolypic analysis by ELISA and Western blotting showed that the high-affinity cationic anti-DNA antibodies during active nephritis were idiotypically different from their low-affinity counterparts during inactive nephritis. The differences in binding affinity and idiotypy of the cationic anti-dsDNA antibodies suggest that certain serum IgG anti-dsDNA antibodies with both cationic charge and high affinity may be associated with active nephritis.
A calreticulin-like protein co-purifies with a ‘60 kD’ component of Ro/SSA, but is not recognized by antibodies in Sjögren's syndrome sera
Authors: LU J , WILLIS A C , SIM R B
Published: July 2010

In this study, we used human tonsils for the isolation of the 60 kD component of the Ro/SSA autoantigen. following the method described by Wu et al. (J Immunol Methods 1989; 121:219–24). Western blot analyses were carried out using Ro/SSA-reactive human Sjögren's syndrome sera, to follow the autoantigen through the purification procedure. A 60 kD Ro/SSA component was eluted as a broad peak from a Mono Q column. Within this peak, a much more abundant protein, comigrating with the Ro/SSA component on SDS-PAGE, was also eluted. The more abundant protein was further purified on a Superose 12 column and its N-terminal sequence was shown to be identical to that of humat calreticulin. The 60 kD Ro/SSA autoantigen was also further purified on the Superose 12 column and was eluted as an asymmetric peak, with the majority being eluted at a position corresponding to 60 kD, whereas the calreticulin-like protein was eluted from the same column as an apparent dimer of approximately 120kD. A panel of five Ro/SSA-reactive human sera reacted with the purified Ro/SSA antigen, but not with the calreticulin-like protein. Therefore, it is clear that the calreticulin-like protein is not a Ro autoantigen and is distinct from the 60 kD Ro/SSA antigen. As the calreticulin-like protein is a much more abtitidant protein than the 60 kD Ro/SSA component, its co-purification with the autoantigen on ion-exchange and its close migration with the autoantigen on SDS-PAGE may explain why peptide sequences for human calreticulin were derived from apparent 60 kD Ro/SSA antigen preparations.