Antigen In Subjects Research Articles

In situ cytokines (IL-4, IL-10, IL-12, IFN-γ) and chemokines (MCP-1, MIP-1α) gene expression in human Leishmania (Leishmania) mexicana infection

Crucial to the defense against Leishmania is the ability of the host to mount a cell-mediated immune response capable of controlling and/or eliminating the parasite. The composition of the cell populations recruited in the early phase of the infection seems to be essential for defining the infection outcomes. The signals that initiate and regulate the early immune response and local accumulation of cell subsets in the skin are poorly understood. We previously studied the in situ expression of cytokine genes in patients with localized cutaneous leishmaniasis (LCL) caused by Leishmania (Leishmania) mexicana. In the present study we examined in situ cytokine (IL-4, IL-10, IL-12, IFN-γ) and chemokine (MCP-1, MIP-1α) gene expression in L. (L.) mexicana active LCL lesions, and in the delayed type hypersensitivity (DTH) skin response to Leishmania antigen in subjects with healed lesion and subclinical infection. Data regarding cytokines were similar to previous studies in patients with active LCL. There were no significant differences in the profile of cytokine and chemokine gene expression in DTH from subjects with healed or subclinical infection. IL-12 gene expression detected in both groups was similar. High expression of MCP-1 was detected in all patients with active LCL. There was no difference in the level of MCP-1 expression between the healed lesion and the subclinical infection groups (p=0.876). IL-12 and MCP-1 in the absence of IFN-γ might be playing a crucial role in infection outcomes at skin level.

Hepatitis C virus F protein: A double-edged sword in the potential contribution of chronic inflammation to carcinogenesis

Persistent hepatitis C virus (HCV) infection can lead to chronic inflammation and even carcinogenesis. This may in part be due to various viral proteins, which affect apoptosis and promote liver cell growth. Recently, researchers reported a novel F protein, an alternative reading frame protein expressed from the HCV core coding sequence. The functional properties of this protein are presently unclear. Thus, we investigated whether F protein participates in the process of chronic HCV inflammation leading to malignant transformation. Serum or peripheral blood from 42 chronic HCV patients or 38 HCV-associated hepatocellular carcinoma (HCC) patients was analyzed for the presence of T lymphocytes and antibodies specific to F protein. Then, the correlation between indicators of F-specific immune response and viral load or serum IL-6 levels was examined. We identified the presence of both T- and B-cell-mediated immune responses specific to such an antigen in subjects with chronic HCV and in HCC patients. Of note, the presence of anti-F-specific antibodies appeared to be negatively correlated with HCV RNA viral load level. Furthermore, circulating IL-6 levels were significantly higher in patients with HCC than in those with chronic HCV. These increased serum IL-6 levels were, in some HCC patients, positively correlated with the presence of anti-F-specific antibodies. Taken together, these results suggest that F protein may participate in viral clearance and have anti-tumor effects, but may also contribute to the persistence of HCV infection in patients with a low viral load. This latter effect may cause hepatic damage leading to carcinogenesis. Elucidation of these F protein-associated contradictory functional activities is required.

Immune response to influenza vaccination in children and adults with asthma: effect of corticosteroid therapy

BackgroundAnnual influenza vaccination is currently recommended as a preventative measure for all patients with asthma. However, the effect of maintenance corticosteroid therapy on the immune response to influenza vaccine has received limited evaluation. ObjectiveIn this study, we evaluated the effect of corticosteroid therapy on the immune response to influenza vaccine in children and adults with asthma. MethodsThis was a substudy of a larger multicenter, randomized, double-masked, placebo-controlled, crossover study investigating the safety of trivalent influenza vaccine in patients with asthma. At baseline, 294 subjects were randomized to receive either placebo first (n=139) or inactivated trivalent split-virus influenza vaccine first (n=155). Study subjects were categorized into 2 groups: subjects in group 1 (n=148) were receiving medium-dose or high-dose inhaled corticosteroids (ICSs) or oral corticosteroids, whereas subjects in group 2 (n=146) were not receiving corticosteroids or were receiving low-dose ICSs. Serum hemagglutination inhibition antibody titers for the vaccine antigens were measured before and 4 weeks after the administration of placebo or vaccine. ResultsSerologic responses to each influenza vaccine antigen were significantly higher in vaccine than in placebo recipients and were similar among influenza vaccine recipients in groups 1 and 2 for the following endpoints: rise in antibody titer, percent of participants who developed a serological response, and percent of subjects who developed a serum hemagglutination inhibition antibody titer ≥1:32. Post hoc subgroup analyses demonstrated an attenuated response to influenza B antigen in subjects receiving high-dose ICS compared with subjects who were steroid-naïve (P<.05). ConclusionThe immune response to the A antigens of the inactivated influenza vaccine in subjects with asthma is not adversely affected by ICS therapy. High-dose ICS therapy may diminish the response to the B antigen of the vaccine, an observation that needs further investigation.

Costimulatory molecule expression on allergen-stimulated PBMC in cedar pollinosis subjects

B7-1 (CD80) and B7-2 (CD86) play important roles in the differentiation of Th1 and Th2 phenotypes. CD40-CD40L interaction supports the expression of CD80 and CD86 on antigen-presenting cells. Blocking studies suggest these molecules also play important roles in sensitization to a cedar pollen antigen by, but very few studies have concerned their effects on subsequent induction by antigens. We investigated the roles of CD80, CD86, and CD40 in the differentiation of Th1 and Th2 subsets after stimulation with the antigen in subjects with cedar pollinosis. Peripheral blood mononuclear cells (PBMC) were isolated from 12 subjects with pollinosis and 11 healthy controls and stimulated with cedar pollen extract. After in vitro stimulation, CD80, CD86, and CD40 expression on CD19+ cells were analyzed by flow cytometry. The production of type 1 and type 2 cytokines in culture supernatants was measured by FLISA. Proliferation studies were conducted in the presence or absence of anti-CD40 or CD86 mAbs. After in vitro stimulation, CD86 and CD40 were significantly up-regulated following stimulation in pollinosis subjects (p = 0.02 and p = 0.04). A significantly higher level of IL-5 (p = 0.02) was produced by PBMC of pollinosis subjects than by those of controls. Allergen-induced proliferation and IL-5 production of PBMC of pollinosis subjects were inhibited by anti-CD86 mAb but not CD40 mAb. These results indicate that the Th2 response predominated in pollinosis subjects and that CD86 rather than CD80 may be the costimulatory molecule involved in the allergen-induced activation of PBMC.

The role of costimulatory molecules (B7-1 and B7-2) on allergen-stimulated B cells in cedar pollinosis subjects.

B7-1 (CD80) and B7-2 (CD86), which are costimulatory molecules in T-cell activation, play important roles in the differentiation of TH1- or TH2-phenotypes. These molecules were also suggested to play important roles in sensitization to a cedar pollen antigen by blocking studies using neutralizing antibodies, but there have been very few studies concerning the effects following induction by antigen. In this study, we investigated the roles of B7-1 and B7-2 in the differentiation of TH1 and TH2 subsets after stimulation with the antigen in subjects with cedar pollinosis. Skin-prick test was performed in nine subjects with pollinosis and in nine normal controls. Peripheral blood mononuclear cells (PBMCs) were isolated and stimulated with Japanese cedar pollen extract. After in vitro stimulation, the expression of CD80 and CD86 on CD19+ cells was analysed by two-colour flow cytometry. Culture supernatants were collected for all subjects and the production of type 1 and type 2 cytokines was measured by ELISA. After in vitro stimulation, the expression of CD80 (B7-1) was upregulated in both pollinosis and control subjects, but no significant difference was observed between the two groups. On the other hand, CD86 (B7-2) was significantly upregulated following stimulation in pollinosis subjects (P = 0.02). A significantly higher level of IL-5 (P = 0.04) was produced by PBMCs of pollinosis subjects than by those of normal controls. A significantly higher level of interferon (IFN)-gamma (P = 0.03) was produced by PBMCs of normal controls than by those of pollinosis subjects. These results indicated that TH2 response was predominant in pollinosis subjects, and that CD19+ cells of pollinosis subjects expressed higher levels of B7-2 than those of control subjects after in vitro stimulation. In pollinosis subjects, B7-2 rather than B7-1 may be the costimulatory molecule involved in allergen-induced activation of PBMCs.

Levalbuterol hydrochloride

Racemic salbutamol (racemic albuterol) ameliorates symptoms of asthmaby activating b-adrenoceptors on nerve, smooth muscle and inflammatorycells within the airways. Racemic salbutamol comprises equal proportionsof 2 isomers: (S)-salbutamol and (R)-salbutamol, with the latter beingexclusively responsible for activation of b-adrenoceptors. Accordingly,within racemic salbutamol it is (R)-salbutamol that efficiently relievesobstruction of asthmatic airways and affords highly effective protectionfrom bronchoconstrictor stimuli, including allergens. During regular use ofracemic salbutamol, there is a progressive decline of protective efficacy anda corresponding intensification of airway responsiveness. This decline islargely absent during regular use of (R)-salbutamol. Consequently,bronchodilator responses to sub-maximal doses of (R)-salbutamol exceedresponses to the equivalent dose of (R)-salbutamol given as the racemate.For example, in asthmatics with baseline FEVs ≤ 60%, 1.25 mg of nebulised(R)-salbutamol achieved a maximal 52% change in FEV while 2.5 mg ofracemic salbutamol only achieved a 38% change in FEV. Since extrapulmonaryeffects (e.g., tremor, heart rate) of b agonists are related to dose andlimit the use of b agonist therapy, (R)-salbutamol at 0.63 mg providesuncompromised efficacy with marked reduction of side-effects. In additionto quantitative differences, the constituent isomers of salbutamol alsoexhibit qualitative differences. Thus, (R)-salbutamol inhibits activation ofhuman eosinophils in vitro whereas, under the same conditions andconcentrations, (S)-salbutamol augments activation of these cells. Thisproperty of (S)-salbutamol may explain why eosinophilia in inducedsputum from subjects with allergic asthma is increased by regular use ofracemic salbutamol. Similarly, the capacity of (R)-salbutamol to suppresshyperresponsiveness of the airways can be contrasted with the capacity of(S)-salbutamol to intensify hyperresponsiveness. This action of (S)-salbutamolwould explain why regular use of racemic salbutamol intensifies thebronchoconstrictor response to antigen in subjects with allergic asthma.Taken together, these findings imply that replacement of racemicsalbutamol by (R)-salbutamol will diminish, or even eliminate, theanomalous actions that have curtailed the efficacy of racemic salbutamol.Pharmacokinetically, (R)-salbutamol exhibits near absolute conformationalstability (i.e., no conversion to (S)-salbutamol). If in vitro anti-inflammatoryactions of (R)-salbutamol are also manifest in asthmatic airways, (R)-salbutamolcould provide a novel approach to asthma therapy which combinesbronchodilation and bronchoprotection with anti-inflammatory efficacy.

Picroliv, the Iridoid Glycoside Fraction of Picrorhiza Kurroa, Selectively Augments Human T cell Response to Mycobacterial Protein Antigens

Mycobacterial and other intracellular parasitic diseases are characterised by a deficiency in antigen specific host T cell responses. We have studied the effect of Picroliv, a standardised fraction of root and rhizome of Picrorhiza kurroa, on proliferative T cell response to the mycobacterial ‘Purified Protein Derivative (PPD)’ antigen in subjects infected with or exposed to mycobacteria (tuberculoid leprosy patients and endemic normals). Coculture of their peripheral blood mononuclear cells with the optimal concentration of Picroliv (0.5 μg/ ml) significantly enhanced the proliferative response to 1/10 optimal PPD dose, as determined by [3H] thymidine incorporation, in the group of ‘low’ responders. The response to PPD of cells from ‘high responders’ and to PHA (phytohaemagglutinin, a non-specific T cell mitogen) remained unaffected by Picroliv which did also not induce cell proliferation on its own. The selective, antigen specific augmentation of human T cell response suggests that Picroliv could be useful as an adjunct to chemotherapy or as a short term prophylactic agent.

Characterization of the bradykinin receptor in the human nasal airway using the binding of [125I]-Hoe 140.

1. The aim of this study was to characterize the kinin receptor in the human nasal airway using [125I]-Hoe 140 binding to a membrane preparation from human nasal turbinates and to compare Ki values from binding displacement by antagonists with the functional effects of these drugs in vivo. We also investigated the effect of Hoe 140 ([D-Arg0, Hyp3, Thi5, D-Tic7, Oic8]-bradykinin), on bradykinin release into the nasal airway. 2. In a membrane preparation from human nasal turbinates removed during surgery, [125I]-Hoe 140 labelled a single, saturable binding site. The equilibrium dissociation constant (at 20 degrees C) for [125I]-Hoe 140 binding to the receptor was 0.46 +/- 0.08 nM. The Bmax was 0.136 +/- 0.003 pmol mg-1 protein and the Hill coefficient was 1.01 +/- 0.07. 3. The association rate constant for [125I]-Hoe 140 binding to the receptor was 0.20 +/- 0.06 nM-1 min-1 and the dissociation rate constant was 0.14 +/- 0.01 min-1. These values were determined at 4 degrees C. The equilibrium dissociation constant calculated from these rate constants was 0.70 nM. 4. Bradykinin and the B2 receptor antagonists, NPC 567, NPC 17731, NPC 17761, [1-adamantane acetyl-D-Arg0, Hyp3, Thi5,8, D-Phe7]-bradykinin, WIN 64338 and Hoe 140 displaced [125I]-Hoe 140 binding: the Ki values from binding displacement are consistent with values expected from a B2 receptor. The B1 agonist, [des-Arg9]-bradykinin and the B1 antagonist, [des-Arg9]-Hoe 140 failed to displace [125I]-Hoe 140 binding at concentrations up to 1 microM. 5. The bradykinin antagonist, Hoe 140, 10 to 200 micrograms, given by intranasal aerosol, produced a dose-related inhibition of the reduction in minimal nasal cross-sectional area (Amin) induced by bradykinin in normal subjects and by house dust mite antigen in subjects with allergic rhinitis to house dust mite. Hoe 140, 10 to 200 micrograms, also caused a dose-related inhibition of the release of albumin into the nasal cavity following challenge with bradykinin. 6. [1-Adamantane acetyl-D-Arg0, Hyp3, Thi5,8, D-Phe7]-bradykinin, 30 to 200 micrograms, caused a dose-related inhibition of the reduction in Amin and the release of albumin into the nasal cavity induced by bradykinin. NPC 567 ([D-Arg0, Hyp3, D-Phe7]-bradykinin) failed to inhibit the reduction in Amin or the release of albumin into the nasal cavity at a dose of 10 mg. 7. Challenge of allergic subjects with house dust mite antigen caused a significant elevation of the bradykinin concentration in nasal lavage fluid and a reduction in Amin. Hoe 140, 100 micrograms, prevented the antigen-induced reduction in Amin and also abolished the antigen-induced increase of bradykinin in nasal lavage fluid. 8. We conclude that there is a B2 bradykinin receptor in the human nasal airway which mediates nasal blockage and plasma extravasation induced by either bradykinin or antigen challenge. It is possible that Hoe 140 inhibits kallikrein in the human nasal airway as well as blocking the B2 receptor.

Novel treatments for allergic rhinitis: An investigation into the role of bradykinin in the human nasal airway

This paper presents a review of the current literature concerning bradykinin and allergic rhinitis and presents novel data investigating the role of bradykinin in the human nasal airway. Studies are being carried out at the present time to investigate the effect of L-NAME on challenge with antigen in subjects with seasonal and perennial allergic rhinitis. No final data are yet available but initial results indicate that, in seasonal allergic rhinitis, L-NAME antagonizes the increase in vascular permeability induced by grass challenge. Future advances in understanding allergic rhinitis will be targeted at a number of inflammatory mediators; however, this paper demonstrates the role bradykinin plays in inflammation of the nasal tissues.

82. Determinants of plasma plasminogen activator inhibitor-1 antigen in subjects attending a metabolic ward

82. Determinants of plasma plasminogen activator inhibitor-1 antigen in subjects attending a metabolic ward

Entomologic and demographic correlates of anti-tick saliva antibody in a prospective study of tick bite subjects in Westchester County, New York.

We measured anti-tick saliva antibody (ATSA) by enzyme-linked immunosorbent assay using whole sonicated Ixodes dammini salivary glands as antigen in subjects with 1) a recent and confirmed I. dammini (n = 100) or Dermacentor variabilis bite (n = 3), 2) erythema migrans (n = 15), 3) late-stage Lyme disease (n = 4), and 4) normal controls without a history of tick bites (n = 5). Tick bite subjects had three ATSA determinations over approximately six weeks. On the first ATSA measurement at a mean +/- SD of 18.5 +/- 19.8 hr after removal of the tick, the subjects bitten by I. dammini had a mean ATSA optical density value (95% confidence interval [CI]) of 0.264 (0.223, 0.305); the corresponding value in controls was 0.142 (0.115, 0.169). There was no consistent change in ATSA levels in individuals with time. Multiple linear regression indicated that tick engorgement (P < 0.01), subject age (higher ATSA with increasing age; P = 0.01), and subject sex (females > males; P = 0.03) were all independent predictors of ATSA levels. Logistic regression revealed that a bite by I. dammini that became engorged (defined as an engorgement index > or = 3.4) was a risk factor for ATSA seropositivity (odds ratio [95% CI] = 6.2 [1.7, 21.8]). Finally, the ATSA test had a sensitivity of 0.81 and a specificity of 0.56 for a bite by I. dammini that became engorged. Overall, the data are further evidence that ATSA is a biologic marker of tick exposure, in that the engorgement index, a surrogate for tick saliva dose, was the strongest independent predictor of antibody response.

In vivo decreased expression of CD25 (p55 chain of IL-2 receptor) on CD3 + T cells correlates with low in vitro responsiveness to Plasmodium falciparum antigen in subjects living in a malaria endemic area

Significant proliferative responses of peripheral blood mononuclear cells (PBMC) to crude Plasmodium falciparum schizont antigen (M.Ag) or purified recombinant 31.1 Ag (part of gp 195) were observed only in 46 and 39%, respectively, of 50 healthy subjects 5 to 63 years old living in Gabon, a malaria-endemic area. High responses to pokeweed mitogen were observed in all the subjects except one. Interferon-γ (IFN-γ) production paralleled the proliferative response, but in some subjects proliferation without a IFN-γ response was observed. The proportion of subjects responding to M.Ag and 31.1 Ag increased with age. By cytofluorometric analysis performed with PBMC from 27 subjects, a substantial proportion of CD3 + T cells was found to bear the activation marker HLA-DR. However, the CD3 + cells expressed very low levels of CD25 (p55 chain of IL-2 receptor). The expression of CD25 on T cells and their capacity to respond to M.Ag were significantly correlated. In four subjects an increase in the percentage of CD3 + cells bearing the very late activation marker VLA-1 was observed.

An evaluation of ovarian carcinoma-associated antigen defined by murine monoclonal antibody CF511 in sera from patients with ovarian carcinoma

Murine monoclonal antibody CF511, raised against human ovarian clear cell carcinoma, detects a glycoprotein (Mr 600 kDa) called CF511 antigen which is elevated in the serum of many patients with ovarian carcinoma. A competitive enzyme-linked immunosorbent assay was developed to detect CF511 antigen in human serum and used to detected CF511 antigen in subjects with ovarian carcinoma and other diseases. No raised levels (less than 18 unit (U) ml-1) of the antigen were found in the serum of 220 normal individuals or of patients with germ cell tumours (n = 6), granulosa theca cell tumour (n = 1), gastric carcinomas (n = 10) and colo-rectal carcinomas (n = 8). Raised serum levels of CF511 antigen were found in 6/46 patients (13.0%) with benign gynaecological tumours (including endometriosis or ovarian cyst), in 5/7 patients (71.4%) with breast carcinoma and 16/21 (76.2%) lung carcinoma patients. In patients with ovarian carcinoma, 42.3% (11/26) of stage I and II, and 96.0% (24/25) of stage III and IV had levels of greater than or equal to 18 U ml-1. In all patients with serial determination of CF511 antigen levels before and after the surgery, the levels of antigen correlated with the clinical course of disease. Determination of CF511 antigen levels may be useful for detection of ovarian carcinoma as well as lung and breast carcinomas and for monitoring progress of disease and response to therapy.

Two Latex Tests for Australia Antigen in Subjects with and without Hepatitis1

Abstract. With latex particles coated with guinea pig or rabbit antibodies to Australia (Au) antigen, one third of Au‐positive acute hepatitis sera gave weak agglutination patterns similar to the nonspecific reaction of 10% of normal sera. More than 10% were negative and the rest caused strong agglutination. After Au antigen had ceased to be detectable by complement fixation (CF) in 23 patients, 9 to 16 still were positive with the latex tests. This is due to rheumatoid factor (RF) or a similar factor appearing during hepatitis, since (a) the latex test was 32‐fold less sensitive than CF for the specific detection of Au antigen; (b) 10 out of 10 latex‐positive CF‐negative hepatitis sera were positive in the RF test; and (c) 20 out of 20 Au‐CF‐negative sera from rheumatoid arthritis patients without hepatitis were positive in the latex‐Au test. In the present form, latex tests are unacceptable for use on patients' sera due to lack of specificity and sensitivity. Qualified use on the healthy population seems acceptable, but only under certain conditions. Parallel results, with quantitative rather than qualitative differences, were obtained with 2 latex tests of different sources and composition.

Two Latex Tests for Australia Antigen in Subjects with and without Hepatitis

With latex particles coated with guinea pig or rabbit antibodies to Australia (Au) antigen, one third of Au-positive acute hepatitis sera gave weak agglutination patterns similar to the nonspecific reaction of 10% of normal sera. More than 10% were negative and the rest caused strong agglutination. After Au antigen had ceased to be detectable by complement fixation (CF) in 23 patients, 9 to 16 still were positive with the latex tests. This is due to rheumatoid factor (RF) or a similar factor appearing during hepatitis, since (a) the latex test was 32-fold less sensitive than CF for the specific detection of Au antigen; (b) 10 out of 10 latex-positive CF-negative hepatitis sera were positive in the RF test; and (c) 20 out of 20 Au-CF-negative sera from rheumatoid arthritis patients without hepatitis were positive in the latex-Au test. In the present form, latex tests are unacceptable for use on patients’ sera due to lack of specificity and sensitivity. Qualified use on the healthy population seems acceptable, but only under certain conditions. Parallel results, with quantitative rather than qualitative differences, were obtained with 2 latex tests of different sources and composition.