PubMed Health⌕ Search

Biomedical subjects

T A McNeill

Publications and source records attributed to T A McNeill.

At least 19 recordsLinked to original sources
PubMed1992

Markers of inflammatory activation: upregulation of complement receptors CR1 and CR3 on synovial fluid neutrophils from patients with inflammatory joint disease.

Expression of the C3 receptors CR1 and CR3 was investigated on neutrophils from paired peripheral blood and synovial fluid samples from 34 patients with inflammatory joint disease (21 patients with rheumatoid arthritis (RA) and 13 patients with other articular diseases (OAD)). Using monoclonal antibodies (anti-CD35, anti-CD11b) and immunofluorescence flow cytometric analyses the percentages of positively labeled cells and the relative fluorescence intensities (as a measure of receptor number) were determined. CR1 and CR3 were found to be present on the majority (> 85%) of circulating neutrophils from normal subjects, RA and OAD patients, and on synovial fluid neutrophils from both patient groups. A strong correlation between neutrophil CR1 and CR3 expression was observed in peripheral blood samples from normal subjects (r = 0.81; P = 0.001), RA (r = 0.79; P = 0.001), and OAD patients (r = 0.83; P = 0.001); in each case the levels of CR3 expression were approximately twice those recorded for CR1. Both CR1 and CR3 expression was upregulated on synovial fluid neutrophils compared with that observed on the corresponding peripheral blood cells. Mean percentage increases observed were: RA patients: CR1, 16.5% (P < 0.001) and CR3, 28.7% (P < 0.001); and OAD patients: CR1, 4.1% and CR3, 26.9% (P = 0.001). Correlation of serum and synovial fluid IL-6, IL-8, and immune complex levels with neutrophil CR1 and CR3 expression failed to demonstrate any significant relationship between the concentrations of these soluble factors and receptor expression. Upregulation of CR1 and CR3 receptors, reflecting neutrophil activation within the inflamed joint, is a consistent finding in patients with inflammatory arthropathies.

Adult↗
PubMed1992

CD4 lymphocyte subset abnormalities associated with impaired delayed cutaneous hypersensitivity reactions in patients with X-linked agammaglobulinaemia.

Circulating CD4 lymphocyte subset (CD45RA; CD45RO; CD29; Leu8) levels were determined in nine patients with X-linked agammaglobulinaemia (XLA), nine patients with common variable immunodeficiency (CVI) and in 18 age- and sex-matched controls. CD4CD45RO and CD4CD29 cells were significantly lower (P less than 0.01) in the XLA patient group (CD45RO, 15.7 +/- 10.2%; CD4CD29, 32.1 +/- 14.6%) compared with CVI patients (61.8 +/- 25.4%; 60.1 +/- 11.2%) and normal controls (43.7 +/- 22.3%, 54.5 +/- 22.0%). The levels of CD4CD45RA and CD4Leu8 cells were not abnormal in the XLA patient group. No selective reduction in CD4 subsets was observed in the CVI patient group. Delayed cutaneous hypersensitivity testing of five XLA and five CVI patients revealed a significantly reduced response to recall antigens in patients with XLA. This may relate to the deficiency of circulating memory T cells observed in these patients.

Adolescent↗
PubMed1991

Predictive value for coeliac disease of antibodies to gliadin, endomysium, and jejunum in patients attending for jejunal biopsy.

OBJECTIVE: To investigate the extent to which the detection of antibodies to gliadin, endomysium, and jejunum predicts the eventual diagnosis of coeliac disease according to the revised ESPGAN diagnostic criteria in a group of patients in whom there is a high suspicion of coeliac disease. DESIGN: Clinical assessment and laboratory analysis of patients with suspected coeliac disease. SETTING: Gastroenterology department of teaching hospital. PATIENTS: 96 adults with suspected coeliac disease attending for jejunal biopsy. MAIN OUTCOME MEASURES: Diagnosis of coeliac disease with the revised criteria of the European Society of Paediatric Gastroenterology and Nutrition in patients with and without antibodies associated with coeliac disease. RESULTS: 28 patients had a clinical diagnosis of coeliac disease, seven of other gastrointestinal diseases, and 12 of miscellaneous diseases; 49 had no diagnosis. Gliadin IgA detected by ELISA was found in all patients with coeliac disease and none of those without, giving a sensitivity, specificity, positive and negative predictive values, and predictive efficiency of 100% for diagnosing coeliac disease within the group. Endomysial IgA was found in 25 (89%) patients with coeliac disease and jejunal IgA in 21 (75%); neither IgA was found in patients without coeliac disease. CONCLUSION: Detection of gliadin IgA by ELISA and to a lesser extent the endomysial IgA should allow better selection of patients for jejunal biopsy and thus make diagnosing coeliac disease simpler and more efficient.

Adolescent↗
PubMed1991

Immunoglobulin isotype composition of circulating and intra-articular immune complexes in patients with inflammatory joint disease.

The immunoglobulin (Ig) heavy chain isotype composition of intra-articular and circulating immune complexes (ICs) were determined by a Raji cell flow cytometric assay in paired serum and synovial fluid samples from 15 patients with rheumatoid arthritis (RA) and 15 patients with other articular diseases (osteoarthritis, ankylosing spondylitis, gout, psoriatic arthritis, Reiter's disease). ICs were most prevalent in synovial fluid samples of patients with RA but were infrequently detected in serum and synovial fluid samples from the non-RA patients. ICs in patients with RA were heterogeneous both in the prevalence of Ig subclasses identified and in the distribution of the respective Ig isotypes within the complexes. Furthermore, differences were observed in the Ig isotype composition of ICs in paired serum and synovial fluid samples indicating that circulating ICs may not always arise simply by spill-over from articular sites. The possible mechanisms for IC formation in RA are discussed with reference to four patients who displayed features of extra-articular disease.

Adult↗
PubMed1991

Comparison of immunofluorescence and an immunohistochemical technique for the detection of perinuclear anti-neutrophil cytoplasmic antibody.

Using the standard indirect immunofluorescent (IIF) technique two types of autoantibodies are detected in the sera of patients with vasculitic disorders. These are cytoplasmic or classical antineutrophil cytoplasmic antibody (cANCA) and perinuclear anti-neutrophil cytoplasmic antibody (pANCA). In order to resolve the problems associated with the detection of pANCA an immunocytochemical technique-alkaline phosphatase anti-alkaline phosphatase (APAAP) was developed and used to detect ANCA in various groups of patients. Comparison with the standard immunofluorescence method showed that the results correlated only when immunostaining patterns were of the cANCA type. Detection of pANCA by APAAP was more uncertain than by immunofluorescence because of the greater number of staining patterns seen. Interference from antinuclear antibodies (ANA) appeared to cause more problems with the APAAP technique and sera containing ANA were not distinguished from pANCA using either immunofluorescence or APAAP. In conclusion, it appears that the APPAP technique is not a reliable method of the screening of ANCA and that pANCA has several antigenic specificities.

Autoantibodies↗
PubMed1991

Flow cytometric analysis of within-strain variation in polysaccharide expression by Bacteroides fragilis by use of murine monoclonal antibodies.

The reactivity of four different monoclonal antibodies (MAbs) with populations of Bacteroides fragilis NCTC 9343, enriched by density gradient centrifugation for a large capsule, small capsule and electron-dense layer (EDL) only visible by electronmicroscopy, was examined. The MAbs reacted strongly with polysaccharides present in both the large capsule- and EDL-enriched populations but not in the small capsule-enriched populations. The pattern of labelling was determined by immunoblotting, immunofluorescence and immuno-electronmicroscopy, and flow cytometry. The MAbs labelled cell membrane-associated epitopes in the large capsule- and EDL-enriched populations and cell-free material in the EDL population. By immunoblotting, ladders of repeating polysaccharide subunits were evident in the EDL population but not in the large capsule population. The proportion of cells labelled within each population was determined by flow cytometry. The reactivity of another MAb with the small capsule population was confirmed by flow cytometry. A qualitative indication of epitope expression was obtained by examination of the flow cytometric profiles. Differential expression of the same saccharide epitope was observed both between and within structurally distinct B. fragilis populations. The MAbs were species-specific and cross-reacted with several recent clinical isolates. These polysaccharides may be relevant to the virulence of B. fragilis.

Animals↗
PubMed1990

A T cell receptor beta chain polymorphism is associated with patients developing insulin-dependent diabetes after the age of 20 years.

We have studied the BglII polymorphism near the T cell receptor beta chain constant region (TcR-C beta) gene, HLA-DR genotypes and certain autoimmune features in 102 patients with type I (insulin-dependent) diabetes. There was a significant decrease in the frequency of the 1:1 genotype (P = 0.008) and an increase in the 1:2 genotype (P = 0.03) of the BglII TcR polymorphism in the group of patients who developed type-I diabetes after the age of 20 years. This group of patients also showed an increased incidence of autoantibodies (especially islet cell antibody), a family history of diabetes and the presence of other autoimmune diseases. The frequency of this polymorphism in patients who developed type I diabetes before the age of 20 years was similar to a non-diabetic group. These results suggest that there are two genetically distinct groups of patients with type I diabetes. HLA-DR3 and HLA-DR4 genotypes were also increased in the diabetic patients but no significant difference was observed between HLA-DR genotypes, the TcR-C beta genotypes, the age of diagnosis or with other autoimmune features. Patients developing type I (insulin-dependent) diabetes after the age of 20 years have an additional genetic susceptibility for diabetes associated with the TcR-C beta gene.

Adolescent↗
PubMed1989

Measurement of circulating immune complexes containing IgG, IgM, IgA and IgE by flow cytometry: correlation with disease activity in patients with systemic lupus erythematosus.

The immunoglobulin (Ig) class of the antibody component of circulating immune complexes (IC) may be an important determinant of their pathogenicity. This study reports the development of a fluorometric immunoassay, using Raji cells as solid phase component and detection by flow cytometry, for the measurement of IC containing IgG, IgM, IgA and IgE. Analytic specificity of the method was established and diagnostic sensitivity determined in groups of patients with various disorders. In a detailed study of 44 patients with systemic lupus erythematosus (SLE), elevated levels of IC were observed in the majority of patients, the prevalence of the respective Ig subclasses within the patient group being IgG-IC (93%); IgM-IC (77%); IgA-IC (59%); IgE-IC (52%). Raised levels of IC (of all classes) correlated with disease activity. Longitudinal study of a patient with acute cerebral SLE revealed elevated IC levels of all four Ig classes at presentation which fell during treatment, coincident with normalization of complement values. The biological consequences of IC of various Ig subclasses is discussed with particular reference to a possible mechanism of IgE-IC mediated tissue damage.

Adult↗
PubMed1988

Determination of activated lymphocytes in peripheral blood of patients with multiple sclerosis.

Using monoclonal antibodies Ta1 and CD25 (interleukin-2 receptor: I-2R) and flow cytometry, the levels of activated lymphocytes in the peripheral blood of 50 patients with multiple sclerosis (16 relapsing inactive; 14 relapsing active; 20 chronic progressive) and 20 normal subjects were investigated. No significant differences were observed in the percentage or absolute numbers of Ta1 and IL-2R reactive lymphocytes between the normal and multiple sclerosis patient groups, irrespective of disease activity. Monitoring peripheral blood lymphocytes with respect to these markers would appear to have little value in the management of multiple sclerosis.

Humans↗
PubMed1988

Detection of circulating immune complexes by Raji cell assay: comparison of flow cytometric and radiometric methods.

Several flow cytometric methods for the measurement of circulating immune complexes (CIC) have recently become available. We report a Raji cell flow cytometric assay (FCMA) that uses aggregated human globulin (AHG) as primary calibrator. Technical advantages of the Raji cell flow cytometric assay are discussed, and its clinical usefulness is evaluated in a method comparison study with the widely used Raji cell immunoradiometric assay. FCMA is more precise and has greater analytic sensitivity for AHG. Diagnostic sensitivity by the flow cytometric method is superior in systemic lupus erythematosus (SLE), rheumatoid arthritis, and vasculitis patients: however, diagnostic specificity is similar for both assays, but the reference interval of FCMA is narrower. Significant correlations were found between CIC levels obtained with both methods in SLE, rheumatoid arthritis, and vasculitis patients and in longitudinal studies of two patients with cerebral SLE. The Raji cell FCMA is recommended for measurement of CIC levels to clinical laboratories with access to a flow cytometer.

Antigen-Antibody Complex↗
PubMed1986

Growth of human B cell colonies from peripheral blood of patients with systemic lupus erythematosus.

Human B cell colonies were grown from peripheral blood of 12 patients with systemic lupus erythematosus (SLE) and from 12 healthy control subjects. The SLE group showed a large increase (p less than 0.001) in the number of colony forming cells (CFC) present in peripheral blood as compared with controls. The CFC were of the pre-B cell type. There was also a loss of OKT8+ cell inhibition of B cell colony growth in the SLE group compared with control subjects.

Adult↗
PubMed1985

Changes in circulating immune complex concentrations and antibody titres during treatment of Q fever endocarditis.

Serum samples from 20 patients with Q fever endocarditis were tested for the presence of circulating immune complexes to see whether their concentrations correlated with antibody titres during treatment and whether they could be used to monitor the response to antimicrobial treatment. Circulating immune complexes were found in all 20 patients. The concentrations in 15 patients correlated with either or both of the Q fever phase 1 and phase 2 antibody titres obtained during treatment. In the other five patients no correlation with the antibody titres was found. There was no association between circulating immune complex concentrations and clinical response to treatment.

Adult↗
PubMed1985

Sexually transmitted diseases, T cell subsets, and sexual practices in homosexual men attending an STD clinic.

Sixty three homosexually active men and 42 heterosexual men answered questionnaires regarding aspects of their social life and sexual practices. Assessment of past sexually transmitted disease showed the homosexual group to have had a significantly greater incidence of syphilis, gonorrhoea, perianal warts, and cytomegalovirus infections. T cell subset counts were carried out, and results for 60 of the homosexual men and 39 of the heterosexual men showed that the homosexuals had a significantly greater mean T cell suppressor cell count (p = 0.0019). The mean T helper cell count was not significantly different between the two groups, but it was significantly more (p = 0.033) in the more promiscuous homosexuals (who had more than 20 sexual partners a year) than in the heterosexuals. No relation was found between T cell subset counts and evidence of past cytomegalovirus infection. The practice of passive anal intercourse, oroanal sex, and swallowing semen during oral sex did not appear to influence T cell subset counts in the homosexuals.

Adult↗
PubMed1985

Biochemical and physiochemical characteristics of a pre-B cell stimulating factor produced by the plasmacytoma cell line LICR LON HMY2.

We have characterized the pre-B cell colony stimulating activity (pre-B cell CSA) from LICR LON HMY2 conditioned medium (CM) by a variety of biochemical techniques. Pre-B cell CSA was found to be associated with a heat stable glycoprotein which has an isoelectric point of 8.3 and a mol. wt, as determined by polyacrylamide gel electrophoresis, of 28-32 kD. The relationship of this activity to previously described factors acting on cells of the B cell lineage is discussed.

B-Lymphocytes↗
PubMed1985

Human B cell colony growth from pre-B cells in vitro.

We describe a simple one-step technique for the growth of human B cell colonies in semi-solid agar in vitro. This method used conditioned medium from the human plasmacytoma cell line LICR-LON-H My 2 as a source of stimulating activity. A linear relationship exists between the number of B cells seeded and the number of colonies formed (r = 0.95). Most colony forming cells, approximately 1 in 500 of B cells seeded, lack surface immunoglobulin, possess Fc receptors and mark with the Leu 12 monoclonal antibody. Cells within developing colonies are found to have cytoplasmic IgM, IgA and IgG depending on the length of time in culture.

B-Lymphocytes↗
PubMed1985

Detection and partial characterization of human B cell colony stimulating activity in synovial fluids of patients with rheumatoid arthritis.

The joint fluids of 37 patients with rheumatoid arthritis, eight patients with traumatic injuries to their joints, two patients with Reiter's syndrome and three patients with psoriatic arthritis were tested for the presence of B cell colony stimulating activity (B cell CSA). B cell CSA was found in all of the joint fluids from the patients with rheumatoid arthritis but in none of the joint fluids from patients with traumatic injuries to their joints or in the joint fluids from the patients with Reiter's syndrome. A trace of B cell CSA was found in the joint fluid of one of the three patients with psoriatic arthritis. There was a positive correlation (r = 0.796) between the amount of rheumatoid factor present in the joint fluids and the titre of B cell CSA. This correlation was highly significant (P less than 0.001). The B cell CSA was localized to component(s) with molecular weight ranges 115-129 kD and 64-72 kD and an isoelectric point of 6.8. Its activity was sensitive to reduction with 2-mercaptoethanol and to the oxidising action of potassium periodate.

Adult↗