bluuebunny/crossref_metadata_2025 huggingface dataset:
Age-related changes in surface antigens on peripheral lymphocytes of healthy children
Authors: OSUGI Y , HARA J , KURAHASHI H , SAKATA N , INOUE M , YUMURA-YAGI K , KAWA-HA K , OKADA S , TAWA A
Published: July 2010

The age-related changes in proportion of various subsets within lymphocytes were investigated in cord blood and peripheral blood from healthy children and adults. The percentages of T and B cells did not show age-related changes, whereas natural killer (NK) cells increased significantly with age. Within lymphocytes or the CD3+ T cell population the proportion of CD45RAbright+ lymphocytes decreased and that of CD45RO+ cells increased, while that of CD45RAdim+ cells showed no age-related change. Within lymphocytes, the percentage of CD45RAbright+ CD4+ cells decreased, together with a decline of that of CD4+ cells. The proportions of CD45RAbright+ CD8+ cells and S6F1bright+ CD8+ cells increased with age, and the age-dependent increase of the proportion of CD8+ cells seems to be mainly attributable to the increases in these subsets. The CD45RAdim+ CD4+ and CD45RAdim+ CD8+ cells co-expressing CD45RO at a low level nevertheless showed no age-related changes. In γδ T cells, both δTCS1+ and δTCS1- T cells increased with age, but the δTCS1-γδ T cells increased more than the δCS1+ subset. Among lymphocytes, the percentages of CD20+, CD21+ and CD22+ cells remained similar, with no age-related changes, but the proportion of CD5+ cells within lymphocytes or B cells decreased. The proportions of CD16+ NK cells among lymphocytes increased with age, and this change was attributable to the increase of CD56+ cells.
Effect of HIV vertical transmission on the ontogeny of T cell antigens involved in the regulation of humoral immune response
Authors: Brugnoni D , Soresina A , Airo' P , Ugazio A G , Notarangelo L D , Cattaneo R , Duse M
Published: July 2010

HIV infection causes progressive impairment of humoral immunity, including defective specific antibody production. To evaluate whether vertical HIV infection interferes with the expression on CD4+ lymphocytes of developmentally regulated molecules, that play a crucial role in the generation of immunological memory (CD45 isoforms) and in attainment of antibody responses (CD40L), 22 HIV-infected children and 36 seroreverted children born to HIV+ mothers were studied. The percentage of CD40L+ PBMC after activation in vitro with phorbol myristate acetate (PMA) plus ionomycin was lower in HIV-infected children than in controls (P < 0·004). This correlated with the depletion of CD4+ lymphocytes (r= 0·75; P < 0·001). CD40L expression rose progressively with age (r= 0·36: P= 0·03) in seroreverted children, but not in HIV-infected children, suggesting that while in normal children in vivo antigen stimulation results in progressive attainment of CD40L expression and thus to effective T–B cell cooperation), this process is largely defective in HIV-infected children, contributing to the genesis of humoral immune deficiency. The proportion of CD4+ cells bearing the CD45RO isoform was increased among HIV-infected infants during the first years of life. However, the percentage of CD4+ CD45RO+ peripheral blood mononuclear cells (PBMC) progressively increased with age in controls (r= 0·69; P= 0·03), but not in HIV-infected children, showing that while vertical transmission of HIV does not prevent CD45RO expression early in life, it is associated with a disturbance of the physiological process of antigen priming, contributing to poor immunological memory to T cell-dependent antigens.
In vitrostimulation of peripheral blood mononuclear cells (PBMC) from HIV- and HIV+ chancroid patients byHaemophilus ducreyiantigens
Authors: Van Laer L , Vingerhoets J , Vanham G , Kestens L , Bwayo J , Otido J , Piot P , Roggen E
Published: July 2010

The cellular immune responses to fractionated Haemophilus ducreyi antigens, coated on latex beads, were assessed in patients with chancroid and in controls, using an in vitro lymphocyte proliferation assay. Several tractions of H. ducreyi antigen revealed stimulating activity. However, only the molecular size ranges 91–78 kD, 59–29 kD, and 25–21 kD induced proliferation that may be specifically related to H. ducreyi infection. Lymphocytes from four HIV- patients, successfully treated for chancroid, were not stimulated by H. ducreyi antigen. In general, lymphocytes from HIV+ chancroid patients were less responsive to H. ducreyi antigen compared with those from HIV- chancroid patients. However, two HIV-infected patients showed exceptionally strong responses to high molecular weight fractions. To our knowledge this is the first report demonstrating that H. ducreyi contains specific T cell-stimulating antigens. Based on this work, further identification and purification of the T cell antigens is feasible.
γδ T cells in rhesus monkeys and their response to simian immunodeficiency virus (SIV) infection
Authors: Gan Y H , Pauza C D , Malkovsky M
Published: July 2010

Recent reports of the increase in peripheral blood γδ T cells in HIV+ patients prompted us to examine the γδ T cell system in rhesus monkeys (Macaca mulatta) and the responses of these cells to SIV infection. Our results reveal differences in the γδ T cell subset composition and their expression of CD8 in the peripheral blood of monkeys and humans. The outgrowth of T cells in response to Daudi cells is similar to that in humans, but the exposure to IL-2 stimulates preferentially the simian Vγ1 subset rather than the Vγ9/Vγ2 subset as found in humans. Upon SIV infection of the monkeys, we observed a transient increase of the percentage of total γδ T cell and the Vγ9 subset. γδ T cells from infected animals also express more activation markers such as CD69, CD44 and the memory marker CD45RO. However, they respond to a lesser degree to Daudi or IL-2 stimulation in the outgrowth experiments compared with uninfected animals, although the subset composition of total γδ T cells is similar in infected and uninfected animals. The results clearly indicate that γδ T cells in rhesus monkeys are influenced by SIV infection. The detailed analysis of the γδ T cell response to SIV infection can serve as a model for understanding human γδ T cell responses to HIV infections.
Immunological markers indicating the effectiveness of pharmacological treatment in human hydatid disease
Authors: RiganÒ R , Profumo E , Ioppolo S , Notargiacomo S , Ortona E , Teggi A , Siracusano A
Published: July 2010

The relation of interferon-gamma (IFN-γ), IL-4, IL-10 production and specific IgE, total IgG, IgG subclass expression to the effectiveness of pharmacological treatment in human hydatid disease (Echinococcus granulosus infection) was evaluated in 27 hydatid patients divided into four clinical groups according to their response to albendazole/mebendazole therapy (full, partial, low and non-responders). After parasite antigen stimulation, peripheral blood mononuclear cells (PBMC) from full responders produced significantly more IFN-γ (P= 0·038), significantly less IL-4 (P= 0·001) and less IL-10 than PBMC from non-responders. PBMC from partial and low responders produced intermediate cytokine concentrations. ELISA determining immunoglobulin production showed that sera from all non-responders had IgE and IgG4 antibodies, both regulated by IL-4. In contrast to IgG4, IgE decreased rapidly in full responders. Full responders also showed the highest percentage of IgG3 reactions. Qualitative analysis of total IgG responses in hydatid patients’ sera determined by immunoblotting showed that binding profiles to hydatid cyst fluid antigen differed in the four groups of treated patients. Non-responders had the highest percentage of reactions to all subunits of antigens 5 and B, and full responders had the highest percentage of reactions to antigen 5 alone. The high IFN-γ production associated with a lack of IL-4 and low IL-10 production in the full responders, and vice versa the high IL-4 and IL-10 production associated with lack of or low IFN-γ production in the non-responders implies Th1 cell activation in protective immunity and Th2 cell activation in susceptibility to hydatid disease. IgE may be a useful marker of therapeutic success in hydatid patients with pretreatment specific IgE antibodies. IgG subclass responses and differential immunoglobulin subclass binding pattern to hydatid antigens may also be useful in the immunosurveillance of hydatid disease.
Interferon-gamma (IFN-γ) and IL-4 expressed during mercury-induced membranous nephropathy are toxic for cultured podocytes
Authors: Coers W , Vos J T W M , Van Der Meide P H , Van Der Horst M L C , Huitema S , Weening J J
Published: July 2010

The subepithelial immune deposits of Dorus Zadel Black (DZB) rats with mercury-induced membranous nephropathy consist of autoantibodies directed to laminin P1 and of complement. The animals develop massive proteinuria within 10–14 days which is associated with obliteration of foot processes of glomerular visceral epithelial cells (GVEC), or podocytes. Previous studies indicate that these autoantibodies are probably not the sole mediator of proteinuria and GVEC damage. In this study we investigated whether circulating or macrophage-derived cytokines can contribute to the GVEC changes as detected in vivo. In vivo at the height of the proteinuria. increased intraglomerular IFN-γ immunoreactivity was found. In diseased rats a five-fold increase in intraglomerular macrophages was found, but we could not detect intraglomerular IFN-α, IFN-β, IL-1β or tumour necrosis factor-alpha (TNF-α) by using immunohistology. Subsequently, we exposed cultured GVEC to these cytokines to investigate their cytotoxic effects on several physiological and structural parameters. IFN-γ and IL-4 were the only cytokines that exerted toxic effects, resulting in a rapidly decreased transepithelial resistance of confluent monolayers. which was closely associated with altered immunoreactivity of the light junction protein ZO-I. IL-4 also affected vimentin and laminin immunoreactivity. IFN-γ and IL-4 only interfered with monolayer integrity when added to the basolateral side of the GVEC, indicating specific (receptor-mediated) effects. Only IL-4 decreased the viability of the cells, and treated monolayers demonstrated an increased passage of the 44-kD protein horseradish peroxidase. From our experiments we concluded that IFN-γ subtly affected monolayer integrity at the level of the tight junctions, and that IL-4 additionally induced cell death. We hypothesize that the toxic effects of the cytokines IFN-γ and IL-4 as seen with cultured podocytes are necessary together with the autoantibodies. for the ultimate induction of proteinuria in mercury nephropathy in the DZB rat.
CD4+/CD8+ ratio of liver-derived lymphocytes is related to viraemia and not to hepatitis C virus genotypes in chronic hepatitis C
Authors: Pham B N , Martinot-Peignoux M , Mosnier J F , Njapoum C , Marcellin P , Bougy F , Degott C , Erlinger S , Cohen J H M , Degos F
Published: July 2010

The pathogenic mechanisms that lead to chronic hepatitis C are unknown. As hepatitis C virus (HCV) has been shown to induce T cell response, we assessed whether a particular T lymphocyte subset could be preferentially detected in the liver of patients with chronic hepatitis C in relation to viraemia or HCV genotypes. The immunophenotypes of liver-derived lymphocytes were analysed in 26 patients by flow cytometry and immunohistochemistry. Viraemia was quantified by branched DNA assay. Using this assay, HCV RNA was not detectable in six patients. HCV RNA was detected in 20 patients, and titres ranged from 8 to 137 × 106 Eq/ml. Genotyping was performed using a line probe assay. Type 1a, 1b, 2a, 3a and 4a were found to infect 2, 10, 2, 7 and 3 patients, respectively. The CD4+/CD8+ ratio of liver-derived lymphocytes was significantly higher (P < 0·01) in patients with detectable viraemia than in patients without detectable viraemia. In contrast, neither the percentage of γ/δ T lymphocytes nor that of CD2+CD57+ cells was different in the groups. When comparing the CD4+CD8+ ratio, the percentage of γ/δ T lymphocytes or CD2+CD57+ cells according to genotype, the differences were not significant. These results suggest that the CD4+/CD8+ ratio of liver-derived lymphocytes is related to viraemia but not to HCV genotypes in patients with chronic hepatitis C, and that T lymphocytes may be involved in the pathogenesis of liver lesions in chronic hepatitis C.
Anti-collagen antibodies in systemic sclerosis and in primary Raynaud's phenomenon
Authors: Riente L , Marchini B , Dolcher M P , Puccetti A , Bombardieri S , Migliorini P
Published: July 2010

The frequency and specificity of antibodies to native and denatured collagens were evaluated in systemic sclerosis (SSc) and in primary Raynaud's phenomenon (PRP) by direct and competitive ELISA. Antibodies reactive with denatured collagen type I (CI) were found in 43% of the SSc sera, and anti-CIV and anti-CV in 31%. In PRP, anti-CI, anti-CIV and anti-CV antibodies were detected in 8% of patient sera. Anti-CI, anti-CIV and anti-CV antibodies reacted with determinants expressed on the native as well as on the denatured molecule. Anti-CI and anti-CIV were cross-reactive; a reactivity with CII and a lower one with CV were detected. Anti-CV antibodies also reacted with CI and CII and, in a smaller proportion of cases, with CIV. Anti-collagen antibodies, affinity-purified from blotted collagen IV and V and cyanogen bromide (CBr)-digested CI, displayed the cross-reactivities shown by inhibition studies on sera. Moreover, antibodies eluted from a CBr fragment of CI reacted with the other CBr fragments as well. These data show that one-third of SSc sera contain antibodies that react with epitopes expressed on native as well as on heat-denatured CI, CII, CIV and CV, and therefore have the potential to bind collagens in vivo.
Investigation of the complement receptor 3 (CD11b/CD18) in human rectal epithelium
Authors: Hussain L A , Kelly C G , Rodin A , Jourdan M , Lehner T
Published: July 2010

Rectal and cervicovaginal mucosa are common routes of transmission of HIV, although the mechanism of transmission is unknown. We have investigated human rectal and cervicovaginal epithelia for the expression of complement receptors (CR) and cell adhesion molecules which may be involved in HIV and other infections. In rectal mucosa, CR3 was detected in the surface and crypt epithelial cells by immunohistology, using MoAbs to CD18 and CD11b in 10 out of 15 specimens. RNA transcripts encoding both CD11b and CD18 were also demonstrated in surface and crypt epithelial cells by in situ hybridization. Although CD11b was detected in the epithelial cells in three out of the 14 cervicovaginal specimens, we were unable to detect CD 18. We suggest that expression of the CD11b/CD18 heterodimer might facilitate transmission of HIV by enhancing binding of HIV–antibody complexes in seminal fluid to epithelial cells. Alternatively, since intercellular adhesion molecule-1 (ICAM-1) is a receptor for CD11b/CD18, this may promote adhesion between epithelial cells and HIV-infected mononuclear cells in seminal fluid.
Peripheral cell-mediated immune response to mycobacterial antigens in inflammatory bowel disease
Authors: Rowbotham D S , Howdle P D , Trejdosiewicz L K
Published: July 2010

A mycobacterial etiology has been proposed In Crohn's disease (CD). We have sought evidence of increased or modified T lymphocyte immune responses to Mycobacterium tuberculosis and Myco. paratuber culosis in patients with CD (n = 13), compared with ulcerative colitis (UC; n = 17) and controls (n = 17). Peripheral blood cells were cultured with phytohaemagglutinin (positive mitogen control), mycobacterial purified protein derivative (PPD) preparations, lysates., column fractions and whole, heat-killed bacteria. Responses of T cells and T cell subsets were assessed by expression of activation markers (CD25. CD69). coupled with blastogenesis assays (3H-thymidine uptake) and estimates of proliferation. Virtually all patients responded to Myco. paratuberculosis and Myco. tuberculosis antigens. There were no significant differences between patient groups, although there was a very high overall correlation (r = 0.95; P<0.0001) between responses to the two mycobacterial species. Most of the activation and proliferative responses resided in the CD4± (T helper) subset. Although up to 15% of CD8± (suppressor/cytotoxic) cells also became activated, the CD8± cells did not proliferate subsequently. Cells expressing the alternate γω form of the T cell receptor (TCR γω±) did not activate or proliferate in response to mycobacterial antigens. There were no differences in any of these parameters between patient groups. We conclude that there is no specific increase or alteration in cell-mediated anti-mycobacterial immunity in inflammatory bowel disease (IBD). Thus our data do not support a mycobacterial etiopathology of Crohn's disease.
'Split tolerance’ induction by intrathymic injection of acetylcholine receptor in a rat model of autoimmune myasthenia gravis; implications for the design of specific immunotherapies
Authors: Ohtsuru I , Matsuo H , Fukudome T , Suenaga A , Tsujihata M , Nagataki S
Published: July 2010

Experimental autoimmune myasthenia gravis (EAMG) in the Lewis rat, induced by a single injection of acetylcholine receptor (AChR) protein, is a model used to study human myasthenia gravis (MG), The production of anti-AChR antibodies In the animal model and human MG is T cell-dependent, and AChR-specific T cells have been considered as a potential target for specific immunotherapy. Intrathymic injection of antigens induces antigen-specific tolerance in several T cell-mediated autoimmune models. We examined the effect of intrathymic injection of AChR on T cell responses and the production of antibodies to AChR in EAMG rats. Primed lymph node cells from rats receiving intrathymic injection of AChR exhibited reduced proliferation to AChR with marked suppression of interferon-gamma (IFN-γ) secretion in the antigen-stimulated culture, compared with those of rats injected with PBS. However, neither anti-Narke AChR nor anti-rat AChR antibody production was suppressed or enhanced in intrathymically AChR-injected animals compared with that of animals injected intrathymically with PBS or perithymically with AChR. This ‘split tolerance’ may be attributable to the suppression of type-1 T helper cells (Th1). Our results suggest that the suppression of Th1 function alone may not be sufficient for the prevention of antibody-mediated autoimmune diseases.
An immunosuppressive murine leukaemia virus induces a Th1 → Th2 switch and abrogates the IgM antibody response to sheep erythrocytes by suppressing the production of IL-2
Authors: Faxvaag A , Espevik T , Dalen A
Published: July 2010

Many retroviruses have tropism for cells in the immune system and have a propensity to induce immunosuppression in the host. Some of the effects of retroviruses on immune cell function are thought to be mediated through cytokines. Friend ImmunoSuppressive virus-2 (FlS-2) is a low oneogenic murine leukaemia virus (MuLV) that induces lymphadenopathy and immunosuppression in NMRI mice. The role of T cell cytokines during the generation of a primary antibody response in healthy and FIS-2-infected mice was studied following the antibody response to sheep erythrocytes by an in vitro immunization (IVI) technique. In cultures from FIS-2-infected mice, the antibody response was reduced compared with cultures from uninfected mice and the production of the Th2 cytokines IL-4 and IL-6 was elevated, whereas the Th1 cytokines IL-2, interferongamma (IFN-γ) and tumour necrosis factor-alpha (TNF-α) were reduced. The suppressed antisheep erythrocyte antibody response in cultures from mice infected with FIS-2 seemed to be caused by an insufficient production of IL-2, since addition of recombinant IL-2, stimulated the antibody response. This effect was also observed in cultures depleted of T cells, indicating a direct effect of IL-2 on B cells. A switch to a Th2 cell response and suppression of IL-2 production might play a central role in the immune cell dysfunction induced by FIS-2.
Immune responsiveness inMycobacterium avium-infected mice: changes in the proportion of T cell subsets and antibody production during the course of infection
Authors: Xu D L , Goto Y , Amoako K K , Nagatomo T , Uchida K , Shinjo T
Published: July 2010

The C57B1/6 susceptible (BegS) and its resistant (Begr) congenic mouse, previously developed by retrogressive backcrossing, were infected with 1 × 106 colony-forming units (CFU) of Mycobacterium avium and bacterial growth and their immune responses during the early and prolonged periods of infection were examined. There was a high proliferation in the liver and spleen of BegS mice, whereas no proliferation was observed in the Begr mice. Similarly, the sizes and weights of these organs were much higher than those of their Begr counterparts. The size and number of granulomas in Begr were also found to be higher than those of Begr. The CD3+ and CD4+ subsets increased dramatically in both mice during the early stage of infection. However, in the later phase of the infection, these populations decreased dramatically in Begr mice, but not in Begr mice, resulting in a depression in cell-mediated immune responses. No significant decrease in cellmediated immune responses was observed in Begr mice even after prolonged infection. ELISA was performed to determine the antibody levels in both mice, and it was found that serum IgG and IgM levels in Begs were comparatively higher than those in Begr mice throughout the period of infection. The Beg gene therefore may have an important role in the maintenance of resistance not only in the early phase but also in the later phase of Myco. avium infection.
Reactive arthritis-associated bacteria can stimulate lymphocyte proliferation in non-exposed individuals and newborns
Authors: Chieco-Bianchi F , Hedley K , Weissensteiner T , Panayi G S , Kingsley G H
Published: July 2010

In reactive arthritis (ReA) a specific T cell response to the triggering bacterial antigen is present in the synovial fluid, while in paired peripheral blood T cells the response is markedly reduced. The proliferative response to ReA-associated bacteria in the peripheral blood of ReA patients was compared with that seen in the blood of healthy adults, who denied exposure to these microbes. and in the umbilical cord blood of newborns, who have clearly not been exposed to bacterial antigen. Peripheral blood mononuelear cells (PBMC) from non-exposed adults and those from umbilical cord blood proliferated to ReA-associated bacteria, whilst little response was seen in ReA PBMC. The response was MHC class Il-restricted, required processing of the bacterial antigen, was seen in both CD45RO+ and CD45RA+ subsets, and was not oligoclonal. These T cell responses are similar to those previously demonstrated in non-exposed individuals to malaria, leishmania and trypanosoma antigen, and may reflect the existence of ‘natural’ T cell immunity to ReA-associated bacteria. The lack of such responses in ReA peripheral blood may suggest that such ‘natural’ responses may restrict the dissemination or progression of infection.
A component of the medicinal herb ephedra blocks activation in the classical and alternative pathways of complement
Authors: Ling M , Piddlesden S J , Morgan B P
Published: July 2010

Extracts of the herb Ephedra sinica have long been used in traditional Chinese medicine for the treatment of, among other conditions, acute nephritis. In preliminary studies it was shown that extracts of ephedra caused inhibition of complement in vitro. We thus set out to isolate the active component(s) of this herb, to examine the complement-inhibiting capacity in sera from different species, and to characterize the mechanism(s) by which it inhibits complement. Aqueous extraction of the herb followed by fractionation using thin layer chromatography (TLC) demonstrated that complement-inhibiting activity resided within a single band, hereafter termed the complementinhibiting component (CIC). which represents an as yet uncharacterized polyantonic carbohydrate molecule, TLC-purified CIC inhibited the classical complement pathway in all species tested (human, pig, guinea pig, rat and rabbit). Using erythrocyte intermediates and sera specifically depleted of individual components it was apparent that CIC inhibited C2. This- finding was confirmed using purified human C2, CIC causing a dose-dependent loss of C2 haemolytic activity. At much higher doses, CIC also showed some inhibiting effect in the terminal pathway, and this was shown to be due to inhibition of C9. In the alternative pathway CIC also showed inhibitory activity, although its site of action in this pathway remains unresolved. In Chinese medicine the herb is taken orally, though no studies of complement levels in patients taking the herb have been reported. Preliminary data indicate that oral administration in rats causes a partial inhibition of serum complement activity. Given the current enthusiasm for complement inhibition as a therapy for inflammatory diseases, this non-toxic, naturally occurring agent might be of therapeutic value.
Cyclosporin A (CsA) modulates the glomerular production of inflammatory mediators and proteoglycans in experimental nephrosis
Authors: Bustos C , GonzÁLez-Cuadrado S , Ruiz-Ortega M , GÓMez-Guerrero C , GonzÁLez E , Plaza J J , Hgido J
Published: July 2010

Nephrosis is characterized by glomerular epithelial cell injury and a decrease in the glomerular basement membrane (GBM) proteoglycan content. Although CsA is a useful treatment for a group of patients with this disease, its mechanism of action is unclear. We have previously shown that in experimental nephrosis there is an increase in the glomerular production of tumour necrosis factor-alpha (TNF-α) and platelet-activating factor (PAF). Here we have studied the effect of CsA on kidney generation of TNF-α and PAF in puromycin aminonucleoside (PAN) nephrosis as well as on the synthesis of proteoglycans by cultured glomerular epithelial cells. Rats receiving CsA had. on day 8 of PAN injection, a significant reduction in proteinuria, blood cholesterol levels and in interstitial mononuclear cells. A diminution in glomerular production and urinary excretion of TNF-α and PAF was also noted. In in vitro studies, at 24 h of incubation PAF and TNF-a induced in glomerular epithelial cells a significant decrease in proteoglycan synthesis. Neither PA F nor TNF-α had any significant effect on glomerular epithelial cell proliferation. CsA alone induced a dose-response increase in proteoglycan synthesis and a slight decrease in cell proliferation, CsA also reversed the inhibitory effect of PAF and TNF-α on proteoglycan synthesis. However, CsA did not alter the pattern of proteoglycan prtxiuction, remaining around 50% chondroitinase ABC-, 15% heparitinase-sensitive. Our results indicate that PAF and TNF-α could be implicated in the pathogenesis of nephrosis through the inhibition of proteoglycan synthesis by glomerular epithelial cells. The beneficial effect of CsA in nephrosis may be due to the recovery of the GBM charge selectivity caused by the normalization of glomerular PAF and TNF-α synthesis and the increase in proteoglycan synthesis by glomerular epithelial cells.
Recombinant soluble FcγRII inhibits immune complex precipitation
Authors: Gavin A L , Wines B D , Powell M S , Hogarth P M
Published: July 2010

Control of IgG immune complex formation and deposition is important in determining the nature and extent of subsequent immune effector responses, and appears to be aberrant in some autoimmune diseases. In this study we demonstrate that recombinant soluble FCγRII (rsFcγRII) is an effective modulator of immune complex formation, delaying immune precipitation in a manner which is dose-dependent, and can be specifically inhibited by anti-FcγRII MoAb Fab’ fragments. This inhibitory role in immune precipitation also provides a possible mechanist explanation for our previous demonstration of the efficacy or rsFcγRII as an inhibitor of immune complex-induced inflammation in the Arthus reaction in vivo. RSFcγRH inhibited immune complex precipitation in two different experimental systems. First, rsFc7RII inhibited the precipitation of 125I-bovine serum albumin (BSA)-anti-BSA complexes in a dose-dependent manner, while an irrelevant protein (soybean trypsin inhibitor) had no effect on the precipitation of the immune complexes. Moreover. RsFcγRII inhibited the precipitation of ovalbumin (OVA) anti-OVA complexes as determined by turbidimetric analysis, where the inhibition of immune complex precipitation by rsFc7RII was dose-dependent and was specifically blocked by prior ineubation with Fab’ fragments of a blocking MoAb to FcγRII. RSFcγRII could inhibit the precipitation of BSA anti-BSA complexes in the presence of excess bystander IgG and did not inhibit complement-mediated prevention of immune precipitation, demonstrating that rsFcγRII did not block C1 binding to the BSA anti-BSA complex. Unlike complement. RSFC7RIL could not cause re-solubilization of pre-formed precipitated BSA- anti-BSA complexes. Soluble FcγRS have been detected in biological fluids of normal and inflammatory disease patients., yet the role of SFcγR is still unclear. However, they now play a potential role in the modulation of immune complex solubility.
Mannose-binding protein in preterm infants: developmental profile and clinical significance
Authors: Lau Y L , Chan S Y , Turner M W , Fong J , Karlberg J
Published: July 2010

The aim of this study was to determine the developmental profile of mannose-binding protein (MBP) in preterm infants. MBP was measured in 885 longitudinally collected serum samples from 168 preterm infants, and 63 were genotyped with respect to the codon 54 mutation in the MBP gene. MBP level/codon 54 genotyping were also determined on the cord blood of 146/123 term infants and 138/123 adults, respectively. The best cut-off values of MBP for dividing preterm, term infants and adults into ‘low’ and ‘high’ M BP groups were 400 ng/ml (55 low, 113 high), 700 ng/ml (35 low, 111 high) and 750 ng/ml (33 low. 105 high), respectively, by achieving the least number of misclassifications according to the codon 54 mutation. The relative risk of the ‘low’ groups for presence of the codon 54 mutation compared with ‘high’ groups were 42 4, 67–9 and 22–9 for preterm, term infants and adults, respectively (P KO 00001). The gestational age and birth weight of the ‘low’(n = 55) and ‘high’(n= 113) MBP groups of the 168 preterm infants were 29.5 ± 2.8 weeks, 30.5±2.8 weeks (p=0.03) and 1230±317g, 1277±289g (p = 0.35). respectively. The mean MBP levels of these two groups of preterm infants were different (P<0001) at all ages measured. As a whole group, the MBP level rose from a mean of 500 ng/ml at 25 weeks gestation to 1700ng/ml at 20 weeks post full-term. The mortality rates of ‘low’ and ‘high’ MBP groups of preterm infants were 22% and 12%, respectively (p-0.113). This difference in mortality was due to gestational age and birth weight standard deviation score (SDS) after adjusting for length of gestation and gender (p = 0.0001) rather than to low MBP levels (p = 0 65). MBP levels were not related to birthweight SDS score (P = 0 26). The mean ± sd. MBP levels for preterm, term infants and adults without the codon 54 mutation were 1225 ±701 ng/ml (n = 45), 2064 ± 829 ng/ml (n= 88) and 2473 ± 1395ng/ml (n = 95), respectively; the corresponding values for those with the codon 54 mutation were 130 ±275 ng/ml (n= 18), 533 ±665 ng/ml (n = 35)and 330±225ng/ ml (n= 28), respectively. Intra-uterine growth retardation in preterm infants does not influence MBP levels. For those without the codon 54 mutation, there is a significant difference in MBP level between the three age groups. For those with the codon 54 mutation, there is a significant difference between preterm and term infants, but not between term infants and adults. We conclude that there is a maturation in MBP levels for preterm infants, and that a moderately low MBP phenotype does not affect survival. We cannot exclude an effect of profoundly reduced MBP levels (characteristic of individuals homozygous for the codon 54 mutation), since no such preterm infant was identified in this study.
Acute phase proteins and recombinant IL-2 therapy: prediction of response and survival in patients with colorectal cancer
Authors: Simpson W G , Heys S D , Whiting P H , Eremin O , Broom J
Published: July 2010

Twenty-four patients with metastatic colorectal cancer were treated with recombinant IL-2 (rIL-2) by continuous intravenous infusion for 5 days (18 · 106 U/m2 per 24 h), followed by three injections of 5-fluorouracil (600 mg/m2) and folinic acid (25mg/m2) at weekly intervals. The response to treatment was assessed using standard UICC criteria (partial or complete response, stasis or progression of disease). The serum concentrations of the acute phase proteins; C-reactive protein (CRP), retinol binding protein (RBP), α1-antitrypsin (α1-AT), transferrin (TF) and albumin were measured. A response to therapy occurred in the tumours of seven (29%) of the 24 patients (two complete and five partial responses). All patients who demonstrated a response to treatment had a serum albumin level of > 37 g/l and a CRP level of · 10 mg/l. In contrast, of the 17 patients who did not respond to therapy, 12 (71%) had a serum albumin of less than 37 g/dl and a CRP of greater than 10 mg/l. Examination of the survival times of the 12 patients who had a pretreatment serum albumin level of less than 37 g/l revealed that all had died within 12 months of cessation of therapy. However, 58% of patients with pretreatment serum albumin levels of greater than 37 g/l survived for longer than 12 months. These results have shown that (i) patients who respond to rIL-2-based therapy and (ii) those patients who have prolonged survival times, can be identified by pretreatment measurement of serum levels of acute phase proteins.
Effects of anti-CD3 monoclonal antibodies on functional activity of lymphocytes: studiesin vivoandin vitro
Authors: Parlevliet KJ , Chamuleau M E D , Yong S-L , Raasveld M H M , Ten Berge I J M , Schellekens P TH A
Published: July 2010

Lymphocyte functional activity was tested in 38 renal transplant recipients receiving induction treatment with various anti-CD3 MoAbs, i.e. OKT3, T3.G2a (an IgG2a anti-CD3 MoAb) or T3.A (an IgA anti-CD3 MoAb of the same idiotype). During treatment with OKT3 and T3.G2a, lymphocyte response to phytohaemagglutinin-P (PHA), as determined with the use of a whole-blood lymphocyte culture technique, decreased significantly. However, during treatment with T3.A PHA response was not affected. Using a conventional lymphocyte culture technique, PHA response was unchanged during treatment with all three MoAbs, indicating that the immunosuppressive effect of OKT3 and T3.G2a is probably dependent upon the presence of MoAb in culture medium and is reversible. In addition, we tested in vitro inhibition of aspecific mitogen- or antigen-induced lymphocyte stimulation by OKT3, T3.A and T3.G2a. It appeared that at low concentrations (< 25ng/ml) T3.G2a and OKT3 exerted a stronger immunosuppressive effect than T3.A. However, at higher concentrations T3.A, OKT3 and T3.G2a were equally immunosuppressive. We conclude that the immunosuppressive effect of T3.A is caused by blindfolding. At low concentrations T3.G2a exerts its immunosuppressive effect mainly through modulation of the CD3 and/or T cell receptor complex, as a result of interaction with Fc receptors on monocytes. At higher concentrations blindfolding of the CD3/T cell receptor complex may contribute to immunosuppression.
The affinity of IgG antibodies to gag p24 and p17 in HIV-1-infected patients correlates with disease progression
Authors: Chargelegue D , Stanley C M , O'toole C M , Colvin B T , Steward M W
Published: July 2010

The affinity of anti-gag antibody was studied for up to 9 years (1984–1993) in sera from 15 HIV-1+ patients with haemophilia. On the basis of their 1993 clinical status patients were divided into two groups: (i) patients who remained asymptomatic (n= 9); and (ii) those who progressed to AIDS between late 1987 and 1993. The affinity constants of antibody for p24 and p17 were determined by a double isotope fluid-phase radioimmunoassay; and the relationships between antibody affinity and titre, patient clinical course, CD4 cell counts and p24 antigenaemia were analysed. The affinity of p24- and p17-specilic antibody was up to 100 times greater in asymptomatic patients than in patients who progressed to AIDS. Patients who developed AIDS either lost or failed to develop high-affinity antibodies early in the infection. Asymptomatic patients maintained high-affinity antibodies for several years; however, in some of these patients the affinity of anti-p24 and p17 antibodies subsequently fell later in the study period. The presence of low-affinity antibody and progressive reduction in the titre of specific antibody were earlier predictors of disease onset than CD4 cell counts. The failure to either develop or maintain high affinity gag-specific antibody suggests an early impairment of T helper function in individuals who progressed to AIDS. The presence of antibody of high affinity could be essential in controlling virus replication and the onset of AIDS.
Linkage of IgA deficiency to Gm allotypes; the influence of Gm allotypes on IgA-IgG subclass deficiency
Authors: Oxelius V-A , Carlsson A-M , HammarstrÖM L , BjÖRkander J , Hanson L Å
Published: July 2010

IgA deficiency (IgAD) is the most common immunodeficiency, characterized by an arrest in B cell differentiation. It has a sporadic occurrence or variable inheritance pattern, and is also linked to the HLA genes. IgA deficiency is sometimes associated with IgG subclass deficiency. In this study the Gm allotypes, as genetic characteristics of the IgG1, IgG2 and IgG3, were analysed in 83 Caucasian IgAD individuals. Half of the patients presented with IgG4 < 0·01 g/l compared with 5% (P < 0·001) in a healthy population. Three of the 83 had significantly low IgG2 and four had significantly low IgG3 levels. Gm allotype frequencies in IgAD deviated compared with a normal population. Of the 83 patients, 44 (53%) showed homozygous G2m(“,”) expression on the IgG2 locus (33% in controls, P < 0·01). In IgAD the Gm(a, g) haplotype was more frequent (43%) compared with controls (31%, P < 0·01). The Gm homozygous phenotype Gm(a', g/a', g) was most common, found in 20 of 83 patients (24%, P < 0·05) compared with controls (14%). On the other hand the Gm(f,n,b) haplotype of IgAD was rare (28%) compared with controls (45%, P < 0·001). The low IgG4, < 0·01 g/l, found in 50% of the patients, was even more frequent (56–69%) among the G2m(“,”) phenotypes. IgG subclass levels were given for different Gm phenotypes of the IgAD group and compared with controls. Significantly low IgG4 was revealed in the Gm(a,“,g/a,”,g) phenotype (P < 0·01) and significantly low IgG2 in the Gm(a,“,g/f,”,b) phenotype (P < 0·01). The Gm(a,“,g/f,”,b) phenotype contained the three patients found with IgG2 levels < - 2 s.d., and the four patients with IgG3 levels < -2 s.d. were present among those with the homozygous Gm(a,“,g/a,”,g) phenotype; both phenotypes with G2m(“,”) on the IgG2 locus. The ‘compensatory’ increase of IgG was significant for both IgG1 and IgG3 in all Gm phenotypes, but in the Gm(a,“,g/f,”,b). Thus, the susceptibility of IgAD with the additional IgG antibody deficiencies, down-regulated IgG4 and IgG2/IgG3, is associated with Gm allotypes, especially the homozygous G2m(“,”) expression on the IgG2 locus.
Low serum levels of dehydroepiandrosterone may cause deficient IL-2 production by lymphocytes in patients with systemic lupus erythematosus (SLE)
Authors: Suzuki T , Suzuki N , Engleman E G , Mizushima Y , Sakane T
Published: July 2010

The principal cause of IL-2 deficiency, a common feature of both murine lupus and human SLE, remains obscure. Recent studies of our own as well as others have shown that dehydroepiandrosterone (DHEA), an intermediate compound in testosterone synthesis, significantly up-regulates IL-2 production of T cells, and that administration of exogenous DHEA or IL-2 via a vaccinia construct to murine lupus dramatically reverses their clinical autoimmune diseases. Thus, we have examined serum levels of DHEA in patients with SLE to test whether abnormal DHEA activity is associated with IL-2 deficiency of the patients. We found that nearly all of the patients examined have very low levels of serum DHEA. The decreased DHEA levels were not simply a reflection of a long term corticosteroid treatment which may cause adrenal atrophy, since serum samples drawn at the onset of disease, which are devoid of corticosteroid treatment, also contained low levels of DHEA. In addition, exogenous DHEA restored impaired IL-2 production of T cells from patients with SLE in vitro. These results indicate that defects of IL-2 synthesis of patients with SLE are at least in part due to the low DHEA activity in the serum.
Regulatory effects of IL-13 on synovial fluid macrophages and blood monocytes from patients with inflammatory arthritis
Authors: Hart P H , Ahern M J , Smith M D , Finlay-Jones J J
Published: July 2010

Activated macrophages are central to the destructive processes of chronic inflammatory arthritis. In this study, it was hypothesized that IL-13, a product predominantly of'Th2-type’ lymphocytes, may be used therapeutically to down-regulate monocyte/macrophage activities at sites of chronic inflammation. Synovial fluid mononuclear cells were isolated from 12 patients with chronic inflammatory arthritis. Peripheral blood mononuclear cells (PBMC) were isolated at the same time as synovial fluid cells from all 12 patients, IL-13 significantly inhibited lipopolysaccharide (LPS)-induced tumour necrosis factor-alpha (TNF-α) production by mononuclear cells from peripheral blood, but not synovial fluid. In contrast, IL-13 inhibited LPS-induced IL-1β production by all cells, and as a positive response to IL-13, CD23 expression was increased on both cell populations. Blood monocytes cultured for 7 days with granulocyte-macrophage colony-stimulating factor (GM-CSF) or M-CSF responded to IL-13 in a manner similar to that detected for synovial fluid-derived cells, with suppression of LPS-induced IL-1β, but not TNF-α, production. In all experiments, the responses to IL-13 were very similar to those detected to IL-4, but differed from those measured with IL-10. Thus, the responses to IL-13 by synovial fluid cells and cultured monocytes are not equal to those of blood monocytes. The similar responses to IL-4 and IL-13 support claims of a common element for signalling from the IL-4 and IL-13 receptors. Furthermore, the activity of a common receptor chain may be altered by monocyte activation and differentiation.
IL-1β and IL-6 stimulate the production of platelet-activating factor (PAF) cultured rabbit synovial cells
Authors: Gutierrez S , Palacios I , Egido J , Zarco P , Miguelez R , GonzÁLez E , Herrero-Beaumont G
Published: July 2010

The aim of this study was to determine whether synovial cells are capable of producing PAF in the presence of cytokines such as IL-1βand IL-6 and other stimuli. Synovial cells were obtained from joints of healthy rabbits. PAF production was assayed by measurement of serotonin release in rabbit platelets and the incorporation of 3H-acetate into PAF. Synovial cells produced PAF after 5 min of incubation with ionophore A23187, reaching the maximal amount at 15 min (4·3 ± 0·7 ± 10−3 pmo1 of PAF/mg protein, P < 0·005, n= 4), and declining afterwards. The treatment of synoviocytes with IL-1β and IL-6 induced synthesis of PAF after 5 min of stimulation, reaching the greatest production at 15 min with IL-6 and 30 min with IL-1β (3·6 ± 1·1 ± 10−3 and 3·3 ± 1·2 pmol of PAF/mg protein, respectively, P < 0·05, n= 4). The incubation of the cells with PMSF, an inhibitor of acetylhydrolase, before the addition of the stimuli, increased the incorporation rate of 3H-acetate, suggesting a rapid degradation of PAF by synoviocytes. These results demonstrate that synovial cells can produce PAF after stimulation with agonists, such as ionophore, and cytokines. Thus, PAF, acting alone or with other mediators, could amplify the inflammatory joint reaction.
Immunohistological analysis of T cell functional subsets in chronic inflammatory periodontal disease
Authors: Yamazaki K , Nakajima T , Hara K
Published: July 2010

IL-2, interferon-gamma (IFN-γ), IL-4 and IL-6 producing T cells in periodontitis and gingivitis-affected human tissues were investigated by immunohistochemistry to clarify the relationship between T cell functional subsets and disease entity. Using alkaline-phosphatase anti-alkaline-phosphatase technique, the relative proportions of each cytokine-producing T cell were calculated in the crevicular 1/3, middle 1/3 and oral 1/3 areas selected in the connective tissue of sections. CD19:CD3 and CD4:CD8 ratios were determined on the serial sections. Compared with gingivitis tissues, the proportion of cytokine-producing cells in periodontitis-affected samples was higher overall in the crevicular 1/3 (P < 0·02). The middle 1/3 exhibited a higher percentage of cytokine-producing cells, except for IL-6-producing cells. Frequencies of cytokine-producing cells in the oral 1/3 did not differ. IL-4 was the prominent cytokine in periodontitis-affected tissues, with the highest proportion detected in the crevicular 1/3. The CD19:CD3 ratio was higher in periodontitis tissues irrespective of the location, indicating a B cell dominance in periodontitis lesions. Furthermore, a significant positive correlation between the proportion of IL-4-producing cells and the CD19:CD3 ratio was noted. The CD4:CD8 ratio consistently exceeded 2·0 in both periodontitis and gingivitis. These results suggest that immunoregulation of both periodontitis and gingivitis are T cell-dependent, but in periodontitis type 2 helper T cells predominate and thereby control B cell activation.
Recognition of a unique peptide epitope of the mycobacterial and human heat shock protein 65–60 antigen by T cells of patients with recurrent oral ulcers
Authors: Hasan A , Childerstone A , Pervin K , Shinnick T , Mizushima Y , Van Der Zee R , Vaughan R , Lehner T
Published: July 2010

T cell epitopes of the 65-kD heat shock protein (hsp) were investigated in patients with recurrent oral ulcers (ROU). Peripheral blood mononuclear cells were stimulated with overlapping synthetic peptide (15ers), derived from the sequence of the 65-kD hsp of Mycobacterium tuberculosis. Specific lymphoproliferative responses were stimulated only with peptide 91–105 in ROU, compared with healthy or disease controls (P < 0·01). This was confirmed by studying 760 short term cell lines generated with the 65-kD hsp and then stimulated with the peptides. The frequency of short term cells lines responding to peptide 91–105 in ROU was significantly greater than in healthy (P < 0.0001) or disease controls (P < 0·01). A comparative investigation with the homologous human 60-kD hsp peptide 116–130 also showed significantly greater lymphoproliferative responses in ROU than in healthy (P < 0·01) or disease controls (P < 0·001). The potential involvement of the T cell epitope 91–105 in the pathogenesis of ROU is supported by finding a significant increase in the lymphoproliferative responses stimulated with peptide 91–105 during the stage of ulceration, compared with remission in 9/11 patients studied sequentially (P < 0·05). The results suggest that oral ulceration might be initiated by the microbial hsp peptide 91–105 stimulating the mucosal Langerhans cells, which may generate autoreactive T cell clones primed to the homologous peptide 116–130.