bluuebunny/crossref_metadata_2025 huggingface dataset:
Actuarial rate of clinical and biological progression in a cohort of 250 HIV-1-seropositive subjects
Authors: VENET A , TOURANI J-M , BELDJORD K , EME D , EVEN P , ANDRIEU J-M
Published: July 2010

This study was undertaken to define the risk of AIDS in a cohort of 250 HIV-seropositivc patients identified by their clinical and biological status. All patients were enrolled between October 1985 and March 1988. They were classified according to clinical classes A, asymptomatic (n= 97); B. lymphadenopathic(n= 123); and C, AIDS-related complex, (n= 30). Also as CD4 cell stages 1 (CD4 ± 600/μl;n= 126); 2(CD4 < 600 and ± 300/μ1; n= 83); and 3 (CD4 < 300/μl; n= 41); and serum p24 antigen positive (n= 48) or negative (n= 202). All patients were evaluated every 3–6 months, until AIDS development or April 1989: 29 cases of AIDS occurred during the follow-up period. The risk of AIDS in class C is very high (64% at 2 years) compared with the 3-year risk of classes A (13%) and B (25%). On the other hand the three CD4 stages have significantly different prognosis (stage 1 6%; stage 2 22%; and stage 3 89%; P < 10−2). Antigen p24 negative and positive patients have also different prognosis (18% and 53%; P < 10−4). Interestingly. p24 antigen conserved its prognostic value in stage 2 (positive 37%. negative 16%) while stages I are at low risk of AIDS and stages 3 at high risk whatever their p24 antigen status. We have also identified the risk of becoming stage 3 and/or p24 antigen positive in p24 antigen negative patients at stages 1 and 2 (respectively, 18% and 47%). This classification should serve to design randomized trials better with experimental drugs with earlier end-points than AIDS onset.
Alveolar macrophages in AIDS patients: increased spontaneous tumour necrosis factor-alpha production inPneumocystis cariniipneumonia
Authors: KRISHNAN V L , MEAGER A , MITCHELL D M , PINCHING A J
Published: July 2010

In order to assess the role of alveolar macrophages and their products in the control of Pneumocystis carinii pneumonia (PCP) and other infections in AIDS, bronchoalveolar lavage cells and peripheral blood mononuclear cells from HIV-positive AIDS/ARC patients (with and without PCP) and HIV-negative patients were counted and cultured in vitro; spontaneous and LPS-induced tumour necrosis factor-alpha (TNF-α) production was measured. Markedly increased spontaneous TNF-α production by alveolar macrophages and, to a lesser extent, peripheral blood monocytes was found in HIV-positive patients with active PCP but not in patients without the infection. Higher TNF production was associated with lower counts of Pneumocystis in the bronchoalveolar lavage fluid. These results suggest that TNF-α production by macrophages may play an important role in the control of Pn. carinii infection in AIDS.
Heterogeneity of binding reactivity to different phospholipids of antibodies from patients with systemic lupus erythematosus (SLE) and with syphilis
Authors: LOIZOU S , MACKWORTH-YOUNG C G , COFINER C , WALPORT M J
Published: July 2010

The binding specificities were investigated of anti-phospholipid antibodies derived from sera from 55 patients with SLE and related diseases, and from 33 patients with syphilis. Antibodies from both these groups of patients bind strongly to cardiolipin in solid-phase immunoassays, but only anti-phospholipid antibodies from patients with autoimmune diseases are associated with thrombotic complications and recurrent spontaneous abortions. IgG anti-phospholipid antibodies from both groups of patients cross-reacted with a range of negatively charged phospholipids, but binding to neutral phospholipids was largely restricted to sera from patients with syphilis. A monoclonal IgMλ anti-cardiolipin antibody, derived from a patient with autoimmunity, was used to inhibit binding of anti-phospholipid antibodies to cardiolipin and to phosphatidic acid. This antibody inhibited the binding of autoimmune sera to cardiolipin more strongly than sera from syphilis patients, but the converse pattern of inhibition of binding to phosphatidic acid was observed. The VDRL litre correlated with anti-phospholipid antibody activity in sera from syphilis patients, but not from those with autoimmunity. Lupus anti-coagulant activity correlated weakly with IgG antibody levels to each of the negatively charged phospholipids among the patients with autoimmunity. Lupus anticoagulant activity did not correlate uniquely with any anti-phospholipid antibody specificity. These results provide further documentation of the great heterogeneity of anti-phospholipid antibodies associated with autoimmune disease and syphilis.
Reactivity of human monoclonal IgM with nerve glycosphingolipids
Authors: HAUTTECOEUR B , SCHMITT C , DUBOIS C , DANON F , BROUET J C
Published: July 2010

We examined the reactivity of monoclonal IgM of sera from patients with neuropathy and monoclonal IgM, with or without antibody activity to myelin-associated glycoprotein (MAG), as well as sera from non-neurologic patients with Waldenström's macroglobulinaemia, with various nerve glycolipids extracts or with purified gangliosides. As expected from previous studies, all (five cases) anti-MAG IgM stained two glycolipids, the chemical characteristics of which corresponded to sulphated glucuronyl-paragloboside (SGPG) and sulphated glucuronyl-lactosaminyl-paragloboside (SGLPG). Five of 12 sera from patients with neuropathy whose IgM was devoid of anti-MAG reactivity stained nerve extracts greatly enriched (98%) with SGPG and SGLPG. Three of these five sera reacted with additional glycolipids and/or gangliosides. Two of 16 sera from patients with macroglobulinaemia without neuropathy reacted strongly with both SGPG and SGLPG. The latter finding as well as the detection of low titre of anti-sphingolipid antibodies in normal sera may cast a doubt on the pathogenetic significance of this antibody activity.
IgA subclass antibodies to gliadin in serum and intestinal juice of patients with coeliac disease
Authors: VOLTA U , MOLINARO N , FRATANGELO D , BIANCHI F B
Published: July 2010

Serum IgA anti-gliadin antibodies (AGA) were positive in 25 (68%) of 37 untreated adults with coeliac disease belonging mostly to IgAl subclass (88%) and only in a few cases to IgA2(12%). Anti-secretory component IgA AGA were present in serum of seven patients (28%) by immunofluores-cence and in nine (36%) by ELISA. The search for IgA AGA in jejunal juice of eight untreated children with coeliac disease was positive in seven cases (88%), with consistent finding of anti-secretory component IgA AGA. These antibodies belonged with equal proportion to IgAl and IgA2 subclasses. This study shows that in intestinal secretions of untreated coeliac disease cases the IgA immune response to gliadin is confined to polymeric anti-secretory component IgA with the same prevalence of IgAl and IgA2 subclasses, while in serum IgA AGA are largely monomeric, more frequently of IgAl than of IgA2 subclass, and with a lower proportion of polymeric anti-secretory component IgA (20–36%). The finding of secretory IgA AGA in serum of patients with coeliac disease could result from a spill-over from the intestinal mucosal synthesis into the circulation.
T cell reactivity to the purified mycobacterial antigens p65 and p70 in leprosy patients and their household contacts
Authors: ADAMS E , GARSIA R J , HELLQVIST L , HOLT P , BASTEN A
Published: July 2010

T cell reactivity to the 70 and 65 kD (p70 and p65) protein antigens derived from Mycobacterium bovis BCG strain was studied by measuring the proliferative responses of peripheral blood mononuclear cells from members of an isolated Aboriginal community resident in the Torres Straits islands. In the nine index leprosy cases the pattern of responsiveness to the purified antigens paralleled that to whole sonicates from M. leprae and BCG. In the 40 contacts of the index cases, a high correlation was observed between the responses to p70 and p65 as well as to the crude sonicates. Significant T cell responses to the purified antigens, as well as the crude sonicates, were obtained with cells from the majority of contacts. Limiting dilution analysis of precursor frequencies in the contacts confirmed the immunogenicity of the purified antigens and excluded both a mitogenic component and the presence of suppressor cells in those moderate or low responders whose blood contained sufficient precursors to be tested. p70 appeared to be more potent in stimulating a proliferative response than p65 at equivalent protein concentrations. No correlation between responder status to either antigen and disease type was detected in families. These findings provide confirmation of the importance of p70 and p65 as major T cell immunogens in man and indicate that they are both potential candidates for inclusion in a bivalent vaccine for leprosy and tuberculosis.
The effects ofPlasmodium falciparummalaria on immune control of B lymphocytes in Gambian children
Authors: WHITTLE H C , BROWN J , MARSH K , BLACKMAN M , JOBE O , SHENTON F
Published: July 2010

Children living in hyperendemic malarious regions have high immunoglobulin levels and an increased frequency of Burkitt's lymphoma. In a study of Gambian children which endeavours to explain these findings we showed that acute P. falciparum malaria caused spontaneous activation and growth of their B lymphocytes in vitro. A high proportion of these cells contained Epstein-Barr nuclear antigen (EBNA). In ancillary experiments aimed at explaining these findings, CD4 helper cells from adult donors were destroyed with monoclonal antibody and complement. This manoeuvre resulted in loss of cytotoxic T cell control of their B lymphocytes when infected with Epstein-Barr virus (EBV). In children with acute malaria, both spontaneous immunoglobulin and antibody production by B cells was increased yet CD4 helper cell control over these cells, as measured by responses to pokeweed mitogen, was found to be intact. Spontaneous and concanavalin A-driven lymphocyte proliferation was depressed. We infer from these findings that in patients with P. falciparum malaria loss of cytotoxic T cell control of the EBV in B cells, possibly due to destruction or dysfunction of a subset of CD4 cells responsible for induction of suppressor/cytotoxic CD8 cells, leads to activation and proliferation of foci of B cells containing EBV. The expanded pool and rapid turnover of these cells may increase chances of malignant transformation leading to the genesis of Burkitt's tumor. Partial loss of suppressor mechanisms coupled with normal CD4 helper/inducer activity may result in high serum levels of immunoglobulin which are characteristic of persons living in malarious regions.
Immunohistochemical detection of terminal complement complex and S protein in normal and pre-eclamptic placentae
Authors: TEDESCO F , RADILLO O , CANDUSSI G , NAZZARO A , MOLLNES T E , PECORARI D
Published: July 2010

Terminal complement complex and S protein were searched for in term placentae obtained from 13 women with normal pregnancy and 15 patients with moderate or severe form of pre-eclampsia. Terminal complement complex was found to localize in the fibrinoid material of the decidua of the basal plate, in the stroma of the chorionic villi and in the vessel walls, as subendothelial deposits. S protein had a quite different distribution, being detected in the syncytiotrophoblast located both in the chorionic villi and in the decidua of the basal plate (DBP) and also on the endothelial cells of fetal stem vessels. Mild deposits of C3 were found in the decidua of the basal plate and also in the stroma and on the basal membranes of the villi. Reactivity for C9 neoantigen was also observed in the cytoplasm of some cells, which were recognized to be macrophages by the presence in their cytoplasm of acid phosphatase and by their reaction with a monoclonal antibody specific for macrophages. Differences in complement deposition in normal and pre-eclamptic placentae were essentially quantitative. Possible mechanisms of complement activation are discussed.
Augmentation of the human monocyte/macrophage chemiluminescence response during short-term exposure to interferon-gamma and tumour necrosis factor-alpha
Authors: KUMARATILAKE L M , FERRANTE A , BATES E J , KOWANKO I C
Published: July 2010

The effects of short-term (30 min) pre-incubation of human monocytes and macrophages (3-day cultured monocytes) with leucocyte-derived human interferon-gamma (IFN-γ) and recombinant human tumour necrosis factor-alpha (rTNF-α) were examined. Pre-incubation of either monocytes or macrophages with rTNF-α or IFN-γ (100 U/5 × 105 cells) augmented their respiratory burst to formyl-L-methionyl-L-leucyl-L-phenylalanine (fMLP), measured by the luminol- and lucigenin-dependent chemiluminescence assay. In addition, both cell types showed a burst of respiratory activity in the presence of rTNF-α or IFN-γ only. The effects of IFN-γ were removed by adsorption with an anti- IFN-γ monoclonal antibody and those of rTNF-α were abolished by heating at 100°C, or by the addition of anti-TNF-α monoclonal antibody. The results demonstrate that both IFN-γ and rTNF-α are stimulators of monocytes and macrophages, and rapidly alter the capacity of the cells to respond to fMLP, which binds to cell surface receptors.
In vivotreatment with anti B-220 monoclonal antibody affects T and B cell differentiation
Authors: ASENSI V , HIMENO K , KAWAMURA I , SAKUMOTO M , NOMOTO K
Published: July 2010

The B220 cell marker is expressed on B cells and on T cell precursors. In order to determine the involvement of the B220 antigen on murine lymphoid differentiation, we treated 5-10-week-old mice periodically with a specific anti-B220 antibody, RA3-6B2, a non-cytolytic IgG2b. After the third injection, a significant reduction (P < 0·02) in the number of thymocytes and less dramatically in the number of splenocytes was observed. This reduction was predominantly due to a decrease of cells carrying the following markers: Thy-1.2+, Lyt-1+, Lyt-2.3+, L3T4+, and asGMl+. Mitogenic response to concanavalin A, phytohaemagglutinin and lipopolysaccharide, mixed lymphocyte reaction, cytotoxic T cell activity, and plaque-forming cell generation were significantly decreased after the treatment (P < 0·01). These results show that the in vivo treatment with anti-B220 monoclonal antibody reduced the number of T and B cells and modified their functional activity. This suggests that the B220 antigen is involved in the maturation of both T and B cells.
Impairedin vitrosurvival of monocytes from patients with HIV infection
Authors: MÜLLER F , ROLLAG H , GAUDERNACK G , FRØLAND S S
Published: July 2010

In vitro survival of monocytes (MO) was studied in 59 patients with HIV infection of different clinical stages. MO from 61 donors and 12 healthy seronegative homosexual men were also examined. Compared with the number of MO seeded, the percentage of adherent monocyte-derived macrophages (MDM) present after 10 days was significantly lower in patients with HIV infection than in the controls. However, the number of viable, non-adherent MO/MDM was similar in patients and controls. Our data indicate markedly decreased in vitro survival of MO from patients with HIV infection. After 10 days, the MDM population in the patient cultures was significantly less differentiated than the control cells, assessed by immunocytochemical staining with monoclonal antibodies against differentiation antigens. Reduced in vitro survival of MO/MDM was associated with low numbers of CD4+ and CDS+ lymphocytes in blood, reduced lymphocyte mitogen responses, presence of HIV p24 antigen in serum and advanced clinical stage. Decreased in vitro survival of MO/MDM may be associated with HIV replication in the cells. Although the level of HIV replication in the cultures was low as assessed by measurement of HIV p24 antigen in culture supernatants and staining of MO/MDM for HIV antigens, cytopathogenic effects of HIV or HIV products cannot be ruled out.
Elevated transcription of heat shock protein gene in scleroderma fibroblasts
Authors: DEGUCHI Y , SHIBATA N , KISHIMOTO S
Published: July 2010

Scleroderma is a systemic disorder characterized by fibrosis, which affects skin, lung, kidney and other organs. Heat shock protein (hsp) (70 kD) has been implicated as an essential element of cell function in cell growth and differentiation. To study the molecular basis of intracellular events in scleroderma fibroblasts, we compared the expression of hsp 70 gene in scleroderma and normal control fibroblasts by nuclear run on transcription assay and Northern blot assay. We show that scleroderma fibroblasts express more than eight times higher level of hsp 70 transcription in normal control fibroblasts at quiescent conditions in the absence of serum. After stimulation with serum, the transcription level of the hsp 70 gene is similar in scleroderma and normal control fibroblasts. Therefore, our results indicate an alteration/activation of intracellular events in scleroderma fibroblasts.
Lymphocyte populations in autopsy bone marrow sections from recipients of allogeneic marrow and non-transplant sudden death cases
Authors: DILLY S A , JAGGER C J , SLOANE J P
Published: July 2010

Femoral marrow, obtained at autopsy, was stained using immunohistological techniques, for T (CD2+) cells, B (CD19+) cells, helper/inducer (CD4+) T cells, suppressor/cytotoxic (CD8+) T cells and natural killer (HNK1+) cells. The numbers present in 13 recipients of allogeneic marrow, 14 to 140 days after transplantation, were compared with those in marrows from nine subjects with no haematological or malignant conditions. In marrow sections from non-transplant subjects, approximately 8% nucleated cells were CD2+ with CD4+ and CD8+ cells present in nearly equal numbers; 1–3% were CD19+ and generally less than 1% HNK1+. The percentages of CD19+ and CD4+ cells were significantly reduced after bone marrow transplantation but, if a correction factor for marrow cellularity was introduced, then CD2+ and CD8+ cell values were also low. The findings were compared with the number of cells transplanted, the time after transplantation, presence of graft-versus-host disease or infection and peripheral blood white cell count, but no correlation was found.
Modulation of human lymphocyte proliferation by amino acids
Authors: CHUANG J C , YU C L , WANG S R
Published: July 2010

The amino acids required for phytohaemagglutinin (PHA) induced lymphocyte proliferation were determined by the 3H-thymidine incorporation in amino acid-deficient media. Results indicate that the PHA-stimulated lymphocytes require alanine and serine in addition to 13 other amino acids present in Eagle's minimal essential medium (arginine, cysteine, glutamine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threoninc, tryptophan. tyrosine, and valine). The omission of any one of the 13 amino acids would stop almost completely the proliferation of PHA-stimulated lymphocytes. The omission of serine from RPMI 1640 medium caused a mean reduction of 64% of cell proliferation, while the addition of alanine to PRMI 1640 culture medium caused a mean increment of 52%. The lymphocyte proliferation appears to be modulated by amino acids in the culture medium, and for optimal growth of lymphocytes, all these 15 amino acids are essential.
Reactive oxygen species modify human DNA, eliciting a more discriminating antigen for the diagnosis of systemic lupus erythematosus
Authors: BLOUNT S , GRIFFITHS H , EMERY P , LUNEC J
Published: July 2010

During the development of an ELISA to measure anti-DNA antibodies in systemic lupus erythematosus (SLE) sera, native dsDNA was found not to be the most appropriate antigen to use in ELISA assays for differentiating between SLE patients and those with rheumatoid arthritis (RA), a disease also associated with circulating serum anti-DNA antibodies. By modifying the ELISA technique to incorporate human DNA, denatured by reactive oxygen species, to detect anti-DNA antibodies in SLE sera, results consistently showed an increase in antibody binding when compared with the native antigen; no such trend was observed in the comparable group of RA patients. Using this assay serum anti-dsDNA antibody levels were measured in a group of 20 controls, 20 RA patients (10 seropositive and 10 seronegative) and 30 SLE patients (15 with clinically active disease, 15 with inactive disease). A comparison with the standard radioimmunoassay used to measure anti-DNA antibodies for the diagnosis of SLE showed that the ELISA assay using modified DNA performed better than the standard radioimmunoassay offering an improvement in both clinical specificity and sensitivity. The improved method particularly reduced the problem of false-negative results for SLE patients shown clinically to be either mildly active or inactive.
Prevalence of hereditary properdin, C7 and C8 deficiencies in patients with meningococcal infections
Authors: SCHLESINGER M , NAVE Z , LEVY Y , SLATER P E , FISHELSON Z
Published: July 2010

High incidence of hereditary complement (C) deficiencies was found among 101 patients who had a meningococcal disease. This study revealed 11 non-related patients with complete C deficiency: five deficient in C7, three in C8, two in properdin and one in C2. Additional C-deficient individuals, most of them with no history of severe bacterial infections, were detected in family studies. The C8-deficient patients were found to have a selective deficiency of the C8-beta subunit and a reduced expression of the alpha/gamma subunit. Only a few families with properdin deficiency have been described so far. However, it is likely that frequent analysis of the activity of the alternative C pathway in survivors of severe bacterial infections will disclose numerous properdin-deficient patients. All our C7-, C8- and properdin-deficient patients are Sephardic Jews whose families originated from Morocco, Yemen (C7 and C8 deficient) or Tunisia (properdin deficient). This and other findings indicate that the type of complement abnormality found in association with meningococcal infections varies with the ethnic origin of the patient.
The effect of treatment with interferon-gamma on type II collagen-induced arthritis
Authors: NAKAJIMA H , TAKAMORI H , HIYAMA Y , TSUKADA W
Published: July 2010

We have investigated the effects of recombinant murine interferon-gamma (rIFN-γ) on type II collagen-induced arthritis (CA) in DBA/1 mice. Therapeutic as well as prophylactic treatment with subcutaneous rIFN-γ, at 105 U/mouse six times a week, inhibited the development of CA without any obvious side effects. The accompanying suppression of anti-CII antibody responses may partly explain the inhibition of CA by rIFN-γ. The possible role of the anti-inflammatory effect of systemic IFN-γ in the inhibition of CA is discussed.
Expression of early activation antigen (CD69) during human thymic development
Authors: JUNG L K L , HAYNES B F , NAKAMURA S , PAHWA S , FU S M
Published: July 2010

The novel early activation antigen, EA1, has been shown to be induced by mitogens, antigens and the tumour promoter, phorbol myristate acetate (PMA), on human lymphocytes. This antigen has been designated to be CD69. EA1 has also been shown to be expressed on thymocytes without exogenous activation stimuli. In order to characterize further the expression of EA1 on thymocytes, the ontogeny of its expression was studied. EA1 appeared between 7 and 9.5 weeks of gestation, after colonization of the thymic rudiment with CD7+ T cell precursors, but before the onset of compartmentalization of the thymus into cortical and medullary zones. After cortico-medullary differentiation, the majority of medullary thymocytes expressed EA1 while only a fraction of the cortical thymocytes expressed this antigen. In the fetal and post-natal cortex, EA1 expression appeared to cluster in the subcapsular cortex. EA1+ cells were also scattered throughout the inner cortex. By two-colour fluorocytometric analysis of post-natal thymocytes, it was shown that EA1 was expressed on 30 to 65% of thymocytes. EA1 was expressed onCD4+ CD8+ as well as on the more immature CD4- CD8- thymocytes. In contrast to circulating T cells, thymocytes were much less responsive to PMA stimulation for the expression of EA1. Molecular characterization showed that EA1 on thymocytes had the same structure as that of activated peripheral T cells. In addition, thymic EA1 was constitutively phosphorylated. Thus, EA1 expression is acquired early during thymic development after colonization of the thymic rudiment by CD7+ T cell precursors. However, the specific role that EA1 may play in the activation and function of developing thymocytes remains to be determined.
Age-associated changes in CD8+ and CD16+ cell reactivity: clonal analysis
Authors: MARIANI E , RODA P , MARIANI A R , VITALE M , DEGRASSI A , PAPA S , FACCHINI A
Published: July 2010

A cloning technique was used to estimate the frequency of proliferating T cell precursors, the growth capacity of clone-forming cells and the functional activity of clones established in vitro from peripheral blood lymphocytes of young and old people. The mean frequency of proliferating precursors was lower in the elderly as was the proliferative capacity of CD8+ clones. In contrast, CD4+ and CD16+ clones showed a proliferation similar to that obtained from young subjects. When the clones were examined for their functional activity, CD4+ clones from both groups failed to show any cytolytic activity, while CD8+ clones exerted cytolysis against K562 and in antibody-dependent cell-mediated cytotoxicity but this function was reduced in clones derived from old subjects. Similarly, CD16+ clones from the elderly showed a decreased activity at some effector-to-target cell ratios. We conclude that the impaired functional activity (T or NK-dependent) found in the peripheral blood of aged subjects persists after in vitro selection when these cells are analysed at clonal level.
Expression of LFA-1 by a lymphoblastoid cell line from a patient with monosomy 21: effects on intercellular adhesion
Authors: TAYLOR G M , BRADDOCK D , ROBSON A J , FERGUSSON W D , DUCKETT D P , D'SOUZA S W , BRENCHLEY P
Published: July 2010

Monosomy 21 (M21) is a rare aneuploid condition which in certain cases leads to reduced levels of chromosome 21 gene products. We have prepared an Epstein-Barr virus lymphoblastoid cell-line (LCL) from patient with M21 who has immunological abnormalities, and analysed the expression of lymphocyte function-associated antigen-1 (LFA-1). This heterodimeric leucocyte integrin consists of CD11a (α) subunits non-covalently associated with CD 18 (β) subunits coded, respectively, by genes on chromosomes 16 and 21. To determine whether monosomy 21 results in decreased expression of LFA-1, monoclonal antibodies were used to compare the expression of CD 1 la and CD18 on the M21 LCL with LCL from trisomy 21 (Down's syndrome, T21), normal controls and a possible case of leucocyte adhesion deficiency. In addition, phorbol-ester-induced homotypic adhesion, an LFA-1-mediated effect, was compared in these LCLs. The results are consistent with a gene dosage mediated reduction of LFA-1 expression by the M21 LCL.
The generation of a ‘tolerogen’ after the ingestion of ovalbumin is time-dependent and unrelated to serum levels of immunoreactive antigen
Authors: PENG H-J , TURNER M W , STROBEL S
Published: July 2010

In an attempt to investigate the molecular basis of the mechanisms underlying oral tolerance, we have evaluated the molecular and biological features of ovalbumin subjected to intestinal processing. Immunoreactive ovalbumin absorbed by the gut was measured by a sandwich ELISA at different times after feeding 25 mg ovalbumin to adult mice. Ovalbumin was detected as early as 5 min after the feed (36.7 ± 16 ng/ml; mean± 1 s.d.) and reached maximal levels at 1 h (73.3 ± 20 ng/ml). Pooled mouse serum, collected 5 min or 1 h after the feed, was transferred intraperitoneally into the naive recipients. Suppression of systemic delayed-type hypersensitivity (DTH) was found in mice receiving 0.8 ml of serum obtained 1 h after ovalbumin feeding but not when using serum obtained 5 min after feeding. In order to transfer samples containing similar levels of ovalbumin, an increased amount (1.3 ml) of serum collected 5 min post-feed was used in further experiments but again failed to induce DTH tolerance. Serum samples obtained 5 and 60 min after ovalbumin feeding were analysed by fast-protein liquid chromatography (FPLC) fractionation followed by ELISA. Both the charge characteristics and molecular weight of intestinally absorbed ovalbumin were indistinguishable from native ovalbumin. Although intact native ovalbumin is the only molecular species detected by ELISA, the results suggest that this has no role in the suppression of DTH responses.
Evidence for circulating activated cytotoxic T cells in HIV-infected subjects before the onset of opportunistic infections
Authors: VANHAM G , KESTENS L , GIGASE P , COLEBUNDERS R , VANDENBRUAENE M , BRIJ L , CEUPPENS J L
Published: July 2010

The activity of both cytotoxic T lymphocyte (CTL) and natural killer (NK) cells were measured cross-sectionally in 43 subjects seropositive for HIV, in 27 HIV- blood donors and in 24 HIV persons from the Outpatients Clinic for sexually transmitted diseases. CTL activity was evaluated using the HL-60 cells coated with OKT3 as the targets and freshly separated peripheral blood lymphocytes as the effectors. In 20 out of 43 HIV+ subjects, CTL activity was significantly enhanced in comparison to the HIV subjects. This lytic activity correlated positively with the percentages of CD3+ HLA-DR+, of CD8+ CR3- and of CD57+CD16- lymphocytes, and was greatly reduced after elimination of CD8+ of HLA-DR+ or of CD57+ cells. The median CTL activity seemed to increase from CDC group II to CDC group IV (Centers for Disease Control classification), but to return back to control levels in those patients with a history of opportunistic infections. NK function in HIV+ subjects was not significantly different from that in the blood donors. In seropositive patients, NK activity correlated positively with the percentages of both CD16+CD57+ and of CD8+ CR3+ cells and was strongly diminished after elimination of CD16 + or of CD57+ cells. There was no significant change in NK function according to the clinical stage. The data show that circulating CD8+HLA-DR+ CTJ57+ T cells in HIV+ subjects are activated cytotoxic T cells and point to progressive (over) activation of this T cell compartment until the onset of opportunistic infections.
In vitroproduction of interferon-gamma by peripheral blood from patients with Graves' disease, Hashimoto's thyroiditis and rheumatoid arthritis
Authors: MATSUBAYASHI S , AKASU F , KASUGA Y , SNOW K , KEYSTONE E , VOLPÉ R
Published: July 2010

The production of interferon-gamma (IFN-γ) by peripheral blood mononuclear cells (PBMC), CD4 cells, or CD8 cells in response to interleukin-2 (IL-2) stimulation has been studied; the samples were obtained from 12 healthy control subjects, 19 patients with Graves' disease (10 hyperthyroid and nine euthyroid), 13 patients with Hashimoto's thyroiditis (four hypothyroid and nine euthyroid), and 15 patients with rheumatoid arthritis (11 active and four inactive). A dose of IL-2 (25 U/ml) was utilized to induce IFN-γ by PBMC from all four groups. The incremental increase in IFN-γ values (with IL-2 stimulation minus without stimulation) was significantly less in PBMC from patients with Graves' disease, Hashimoto's thyroiditis, and rheumatoid arthritis than that in PBMC from control subjects. The values from PBMC in patients with Graves' disease in a euthyroid state were below normal but greater than those from patients with Graves' disease in a hyperthyroid state. The incremental increase in IFN-γ values from Graves' disease PBMC correlated with the serum TSH values (r=0.622, P < 0.01), but not with thyroid autoantibodies (anti-thyroid microsomal antibodies, anti-thyroid microsomal antibodies, nor TSH-binding inhibitory immunoglobulin activities). The incremental increase in IFN-γ from PBMC from both control subjects and Graves* disease was correlated with that from CD4 cells (r=0.711, P < 0.01), but not with that from CD8 cells. The production of IFN-γ in response to IL-2 from PBMC in Graves' disease correlated inversely with thyroid function, appearing to reflect the very effect of hyperthyroidism in this process. The precise explanation of these phenomena remains unclear. The decreased response of IFN-γ to IL-2 stimulation by PBMC from patients with Graves' disease, Hashimoto's thyroiditis, and rheumatoid arthritis seems to be a non-specific phenomenon occurring in both organ specific autoimmune disease and systemic autoimmune disease. It may be due to a down-regulation in autoimmune disease of CD4 cells in response to IL-2, a decreased level of IL-2 cellular receptors or a decreased receptor affinity, associated increased soluble IL-2 receptors, or a defect of the intra-CD4 cellular IL-2 signal to produce or release IFN-γ in the conditions studied.
Cord blood B cells are mature in their capacity to switch to IgE-producing cells in response to interleukin-4in vitro
Authors: PASTORELLI G , ROUSSET F , PENE J , PERONNE C , RONCAROLO M G , TOVO P A , DE VRIES J E
Published: July 2010

Neonatal B cells have been considered immature because of their impaired capacity to produce immunoglobulins in response to polyclonal activators in vitro. Here we demonstrate that cord blood mononuclear cells (MNC) produce normal levels of IgE in vitro when cultured in the presence of interleukin-4 (IL-4), indicating that the B cells are mature in their capacity to switch to IgE-producing cells. However, in contrast to adult peripheral blood T cells, cord blood T cells failed to produce detectable levels of IL-4 upon activation by phytohaemagglutinin (PHA) concanavalin A (Con A) or combinations of PHA and the phorbol ester TPA. Interferon-gamma (IFN-γ) production by cord blood T cells following activation by Con A or PHA was also strongly reduced. However, high levels of IFN-γ, significantly higher than those produced by adult T cells, were synthesized in response to combinations of PHA and TPA, indicating that IFN-γ production by cord blood T cells is not intrinsically defective. In contrast, cord blood T cells produced levels of IL-2 that were significantly higher than those obtained by adult T cells tested in parallel. Collectively, our data indicate that the minimal levels of IgE production measured in cord blood (< 1 U/ml) are not due to immaturity of the cord blood B cells, but may be associated with the failure of cord blood T cells to produce detectable levels of IL-4, which has been shown to be responsible for induction of IgE synthesis both in vitro and in vivo.
The capacity of interleukin-4 to inducein vitroIgE synthesis by B cells of patients with common variable immunodeficiency
Authors: PASTORELLI G , RONCAROLO M G , PERONNE C , TOVO P A , DE VRIES J E
Published: July 2010

Interleukin-4 (IL-4) has been shown to induce IgE synthesis by peripheral blood mononuclear cells (PBMC) of normal donors in vitro. However, induction of PBMC of patients with common variable immunodeficiency (CVI) with IL-4 resulted in IgE production in only two out of eight cases tested. PBMC of the first patient that produced IgE in response to IL-4 also secreted normal levels of IL-4 upon activation. PBMC of the second patient secreted very low levels of IL-4 in vitro which may account for the very low serum IgE levels in this patient. Of the other six patients who had very low serum IgE levels and whose PBMC failed to produce IgE in response to IL-4 in vitro, five did not secrete IL-4 upon in vitro activation. The capacity of the T cells to produce IL-4 was intact in the sixth patient. Collectively our data indicate the PBMC of the majority of patients with CVI are defective since they failed to respond appropriately to IL-4 and they failed to produce IL-4, contributing to the view that CVI is a heterogeneous disorder in which a variety of T and B cell defects occur.
Chronic oral administration of dexamethasone to rats increases cytotoxicity, but not interleukin-1 elaboration, by alveolar macrophages
Authors: BECK J M , SUZARA V V , SHELLITO J
Published: July 2010

Chronic administration of corticosteroids has been used to induce pulmonary infection in animals, but the specific mechanisms by which corticosteroids modulate pulmonary host defence have not been clarified. Specifically, little is known about how corticosteroids influence the function of lung cells, such as alveolar macrophages. Cytotoxicity and interleukin-1 elaboration are two important mechanisms of macrophage defence against pathogens. To determine whether chronic administration of dexamethasone alters cytotoxicity and interleukin-1 elaboration by alveolar macrophages, we studied alveolar macrophages from rats treated with oral doses of dexamethasone for 2 weeks. We found that unstimulated alveolar macrophages from dexamethasone-treated rats exhibited increased cytotoxicity compared with alveolar macrophages from control rats. Moreover, alveolar macrophages from both groups of rats showed enhanced cylotoxicity after in vitro interferon-gamma and lipopolysaccharide treatment, in a dose-dependent manner. Although no spontaneous interleukin-1 elaboration was detected from alveolar macrophages from either group of rats, lipopolysaccharide increased interleukin-1 elaboration by alveolar macrophages from both groups of rats equivalently. These results indicate that chronic oral administration of dexamethasone to rats increases cytotoxicity, and does not alter the capacity of alveolar macrophages to elaborate interleukin-1. Therefore, chronic corticosteroid administration appears to produce selective alterations in these defence mechanisms of alveolar macrophages.
Effect of IgG for intravenous use on Fc receptor-mediated phagocytosis by human monocytes
Authors: JUNGI T W , BRCIC M , KUHNERT P , SPYCHER M O , LI F , NYDEGGER U E
Published: July 2010

Polyspecific IgG given intravenously at high doses (IVIG) is used for immunomodulatory therapy in autoimmune diseases such as idiopathic thrombocytopenic purpura and myasthenia gravis. It is assumed that the clinical effect is brought about in part by a modulation of mononuclear phagocyte function, in particular by an inhibition of Fc receptor (FcR) mediated phagocytosis. In the present study, the effect of IVIG on FcR-mediated phagocytosis by monocytes was analysed in vitro. Since monocytes exposed to minute amounts of surface-bound IgG displayed impaired phagocytosis of IgG-coated erythrocytes (EA), the effect of IVIG was studied with mononuclear cells suspended in teflon bags in medium containing 10% autologous serum and IVIG 2–10 mg/ml). Monocytes pre-exposed to IVIG and then washed, displayed impaired ingestion of EA when compared with control cells cultured in 10% autologous serum only. The decrease in phagocytosis was observed with sheep erythrocytes treated with either rabbit IgG or bovine IgGl and with anti-D-treated human erythrocytes. This suggests that phagocytosis via both FcR type I (FcRI) and type II (FcRII) was decreased. The impairment of phagocytosis was dependent on the presence of intact IgG and was mediated by IVIG from nulliparous donors and from multigravidae to the same extent, suggesting that alloantibodies contained in IVIG have a minor role in modulating FcR-mediated phagocytosis by monocytes. A flow cytometric analysis using anti-FcRI, FcRII and FcRIII monoclonal antibodies showed that IVIG treatment upregulated FcRI expression but did not significantly alter the expression of FcRII and FcRIII.
CD8+/DR+ T gamma cells inhibit the autologous mixed lymphocyte reaction
Authors: HAYNES M K , MILLER J , FULLER L
Published: July 2010

The proliferative response of T cells during autologous mixed lymphocyte reactions (AMLR) was affected by depletion of IgG Fc receptor+ T lymphocytes (Tg). Removal of Tg cells resulted in enhanced proliferation, and EA-rosette isolated Tg cells, when added to AM LR cultures as irradiated third components, reduced the uptake of 3H-thymidine by 63–87% in a dose-dependent manner. Negative selection using an avidin-biotin affinity chromatography technique demonstrated that the suppression was mediated by DR+ Tg cells; the major proportion of which also expressed the CD8 antigen. By comparing AMLR supcrnatants collected from control (lacking Tg) and suppressed (containing Tg) cultures on days 2, 3, and 4, it was established that supernatants from suppressed cultures had significantly reduced levels of cytokine activity. These data indicate that the CD8 +/DR+ Tg cells function as suppressor cells during an AMLR and reduce the proliferative response by inhibiting AMLR responder T cells from producing the cytokines necessary for in vitro growth.
Characterization of two monoclonal antibodies (UCL4D12 and UCL3D3) that discriminate between human mantle zone and marginal zone B cells
Authors: SMITH-RAVIN J , SPENCER J , BEVERLEY P C L , ISAACSON P G
Published: July 2010

Two new monoclonal antibodies (MoAbs), UCL3D3 and UCL4D12 were obtained following immunization with follicular lymphoma (UCL3D3) or low-grade primary B cell gastric lymphoma cells (UCL4D12). In normal splenic white pulp, tonsil and small intestinal Peyer's patches, UCL4D12 recognizes marginal zone B cells and a subpopulation of follicle centre cells, whereas mantle zone B cells are UCL4D12 negative. In contrast, UCL3D3 recognizes mantle zone B cells and follicular dendritic cells, but not marginal zone B cells or follicle centre B cells. Double-immunofluorescence studies showed that in the splenic white pulp, these antibodies stain reciprocally. The majority of UCL3D3+ cells are slgM+ andsIgD+ whereas a higher proportion of UCL4D12+ cells express surface IgM (sIgM) but not surface IgD (slgD). Less than 10% of splenic B cells express both 3D3 and 4D12 antigens. None of the cell lines tested expressed either antigen. Functional studies showed that both antigens play a role in B cell activation as the MoAbs increase the mitogenic effect of Staphylococcus aureus Cowan I on tonsil B cells. This effect was maximal at 72 h in culture. TPA activation was reduced, and no effect was observed with anti-immunoglobulin (anti μ) or CDw40 (G28.5). UCL3D3 and UCL4D12 did not show any stimulatory effect on their own. Biochemical studies show that both MoAbs recognize proteins of 80–90 kD under reducing conditions. These two MoAbs appear to recognize new B cell surface antigens which may be useful for identifying subpopulations of B cells.
Cytostasis of different tumours by a murine PPD-reactive CD4+ T lymphocyte clone is mediated by interferon-gamma and tumour necrosis factor alone or synergistically
Authors: WING M G , MONTGOMERY A M P , HARLEY C , LACHMANN P J
Published: July 2010

We have shown that a murine CD4+ PPD-reactive T lymphocyte clone was weakly cytotoxic towards the syngeneic tumour B16 melanoma and MC6A fibrosarcoma which had been coated with PPD using a monoclonal antibody-PPD heteroconjugale. Cell-free supcrnatants produced by PPD-stimulated T lymphocyte clones were however highly cytostatic for the two tumour targets when assayed over 48–72 h. In this study we have demonstrated good litres of tumour necrosis factor (TNF) and interferon-gamma (IFN-γ) in the supernatants. which accounted for their observed cylostatic activity on the tumour targets. The high level of cylostasis seen with the B16 melanoma using the supernatants could be attributed to their sensitivity to the cytostatic activity of IFN-γ; the lower levels of cytostasis seen with the IFN-γ-resistant MC6A target was the result of IFN-γ increasing the sensitivity of this target to TNF. Antibodies to IFN-γ were able to neutralize the majority of the cytostatic activity of the supernatants on both targets, consistent with the role demonstrated for this lymphokine.
Bacteroides gingivalis-specificserum IgG and IgA subclass antibodies in periodontal diseases
Authors: OGAWA T , KUSUMOTO Y , HAMADA S , McGHEE J R , KIYONO H
Published: July 2010

The level of serum IgM, IgG and IgA antibodies including IgG1. IgG2, IgG3, IgG4, IgA1 and IgA2 subclass-specific antibodies to Bacteroides (Porphyromonas) gingivalis fimbriae and to lipopolysaccharide(LPS) were analysed in paiients with different forms of periodontal disease (PD) and control subjects by ELISA. Among PD subjects, sera obtained from adult periodonitis (AP). rapidly progressive periodontitis (RPP) and gingivitis contained high litres of fimbriae-specific IgG antibodies (7500–15000 ELISA units) followed by IgA (90–700 units) and IgM (30–90 units). In contrast, sera from localized juvenile periodontitis (LJP) subjects exhibited much lower titres of fimbriae-specific IgG (89 ± 11 units), IgA (31.5 units) and IgM (17 ± 3 units) antibodies. A similar response pattern was also seen in sera from normal subjects aged 35–41 years who practice normal oral hygiene, while sera of younger adults (aged 18–24) with superior hygiene did not have any antigen-specific antibodies. Analysis of IgG subclass anti-fimbriae responses revealed that the major response was IgG3 followed by IgG1, IgG2 and IgG4 in AP, RPP and gingivitis. Although lower, a similar pattern of IgG subclass titre was seen in LJP and normal subjects aged 35–41 years. When IgA subclass responses were measured in AP and RPP, higher titres of the fimbriae-specific response were noted with IgAl when compared with IgA2. However, lower but approximately equal levels of fimbriae-specific IgAl and IgA2 titres were seen in other PD groups. When anti-B. gingivalis LPS-specific responses were measured, the sera of AP patients contained high levels of IgG antibodies (2265 ± 224 units) followed by IgA (411 ± 90 units) and IgM (214 ± 56 units). Further. IgG anti-LPS responses were mainly IgG2 followed by IgG4. IgG3 and IgGI. For IgA subclass responses, higher titres of anti-LPS-specific antibodies were noted in IgA2 subclass over IgAl. These results showed that higher anti-B. gingivalis antibody responses occur in PD when compared with healthy individuals and protein and lipid-carbohydrate antigens of B. gingivalis induce distinct patterns of antigen-specific IgG and IgA subclass responses.
Macrophage procoagulant activity as an assay of cellular hypersensitivity to gluten peptides in coeliac disease
Authors: DEVERY J M , GECZY C L , DECLARLE D , SKERRITT J H , KRILLIS S A
Published: July 2010

Gluten and casein digests were tested for their ability to induce a cellular immune response on peripheral blood mononuclear cells (PBM) obtained from coeliac patients as well as healthy volunteers and disease control patients using the macrophage procoagulant assay. PBM from coeliac patients who had been on a gluten-free diet for less than 2 years responded strongly to gluten peptides, while coeiiac patients at diagnosis or who had maintained a strict gluten-free diet for longer than 5 years showed weaker responses. PBM from healthy volunteers did not respond to gluten or casein peptides, whereas those from patients with Crohn's disease displayed weak reactivity to gluten and casein peptides. Our study using the macrophage procoagulant assay confirms previous findings that lymphoid cells from patients with coeliac disease exhibit a specific cellular immune response to gluten. This assay represents an alternative measure for cell-mediated immunity and is technically much simpler than the previously described leucocyte migration inhibition assay. Macrophage procoagulant activity is measured using a simple plasma recalcification time assay or spectrophotometrically using commercially available chromogenic substrates.