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Biomedical subjects

J M Rolland

Publications and source records attributed to J M Rolland.

At least 55 records · Page 3Linked to original sources

T cell response to grass pollen allergens: correlation with skin test reactivity and serum IgE levels.

T cell proliferative responses to rye and Bermuda grass pollen allergens have been studied in a series of 51 atopic and 18 non-atopic subjects. Mean T cell responses were higher in the atopic group than in the non-atopic group (P < 0.001), and there was a strong correlation between the magnitude of reaction in the T cell assay and in the skin test (rye P < 0.01, Bermuda P < 0.05). A similar association was shown between T cell reactivity and serum levels of allergen-specific IgE (rye P < 0.05, Bermuda P < 0.05), but no relationship was found between serum allergen-specific IgG levels and any other parameter studied. T cell reactivity was not found in three cord blood samples tested. Discordance between positivity for T cell responses and skin test reactions in some cases might reflect reactivity by T cell subsets that promote IgG antibody or cell-mediated responses without IgE antibody production. A precise knowledge of T cell recognition of grass pollen allergens will provide exciting new prospects for more effective and safer immunotherapy strategies for allergic diseases including asthma.

Adult↗

[False aneurysm of the left ventricle and coronary aneurysms in Behçet disease].

A false left ventricular aneurysm and coronary artery aneurysm were discovered in a 29 year old patient with Behçet's syndrome. The operation under cardiopulmonary bypass consisted of closing the neck of the false aneurysm by an endo-aneurysmal approach with a Gore-Tex patch. The coronary artery aneurysms were respected. There were no postoperative complications. Cardiac involvement is rare in Behçet's syndrome (6%). The originality of this case is the association of two aneurysmal pathologies: the coronary and ventricular aneurysms due to the angiitis and the myocardial fragility induced by ischaemia.

Adult↗

Autoantibodies to neurons and to the cytoskeleton in small cell carcinoma with paraneoplastic sensory neuropathy.

Autoantibodies to neurons and to the cytoskeleton were demonstrated in the serum of a patient with small cell carcinoma of the lung (SCCL) and paraneoplastic sensory neuropathy. The serum reacted by immunofluorescence with the nuclei of neurons, and with cytochalasin B-sensitive "stress fibres" of cultured cells. The serum also reacted by immunofluorescence with the nuclei of some cultured cell lines. Immunoblotting experiments with brain tissue, with SCCL, HeLa and other cultured cells showed that the serum reacted with 1-4 bands of 35-39 kDa apparent m.w. Two dimensional immunoblotting showed that these molecules had a neutral pI. Antibodies, affinity-purified by elution from the 35-39 kDa bands, gave staining of the nuclei of neurons and of cultured cells and immunoblotted the same 35-39 kDa antigens. These observations show that the anti-neuronal autoantibody reacts not only with neurons and with SCCL but also with some cultured cell lines. Molecular mimicry has been invoked as the basis for the reactivity of this autoantibody with exposed epitopes on SCCL and on neurons.

Animals↗

Analysis of early lymphocyte activation events by fluorescence polarization flow cytometry.

After short-term (up to 4 h) stimulation with mitogen or antigen, lymphocytes were incubated with fluorescein diacetate and the polarization of fluorescence from intracellular fluorescein was measured on a specially adapted FACS II. This flow cytofluorimetric method to assay early changes in activated lymphocytes gave a reproducible response to the mitogens phytohaemagglutinin (PHA), concanavalin-A and the monoclonal antibody OKT3, recognized at 1 h by decreased polarization. A response by immune spleen cells to the antigen dinitrophenyl-ovalbumin was revealed at 4 h. The calcium ionophore A23187 induced an increase in polarization after only 10 min. The PHA polarization response was shown to be dependent on PHA binding, PHA dose, T cells, calcium ions and an intact cytoskeleton. The cellular events monitored by the polarization change are presumably altered fluidity of the probe's microenvironment due to conformational change in macromolecules to which the probe has bound or to dissociation of the probe into the aqueous phase. The fluorescein fluorescence polarization assay is a reliable and sensitive monitor of early lymphocyte activation events and, coupled with the use of a flow cytometer, permits study of particular subpopulations of responding cells.

Acetylgalactosamine↗

Occult ovarian failure: a syndrome of infertility, regular menses, and elevated follicle-stimulating hormone concentrations.

Ten women with infertility, regular menses, and elevated plasma FSH concentrations after a failed in vitro fertilization attempt were studied throughout a spontaneous menstrual cycle. Plasma estradiol, progesterone, inhibin, LH, and FSH concentrations were measured by RIA on days 1, 8, 15, and 22 and compared with the ovarian steroid and gonadotropin profiles obtained from seven endocrine-normal women. The elevated FSH concentrations in the hypergonadotropic group were not associated with significant changes in E2 and P4, but an increase in LH concentrations was found on days 1, 8, and 22 (medians of 18 and 4, 17 and 6, and 7 and less than 3 U/L for the hypergonadotropic and normal groups, respectively; P less than 0.01). Their plasma inhibin concentrations [213, 242, 747, and 561 U/L (median values on days 1-7, 8-14, 15-21, and 22-28)] were normal. Autoantibodies to adrenal, thyroid, or ovary were present in five (50%) women, and antiovarian antibodies were present in 4. Two women gave a family history of thyroid disease, and one woman was hypothyroid. Repeat assessment 3-6 months revealed persistently elevated FSH concentrations in five (63%) of eight women; the other three had normal ovarian steroid and gonadotropin concentrations. The triad of infertility, regular menses, and elevated plasma FSH concentrations describes a group of women with occult ovarian failure, a condition of compensated granulosa cell function, which may be an early stage of premature ovarian failure. These women with occult ovarian failure had an impaired response to ovarian hyperstimulation and may be at increased risk of developing polyglandular autoimmunity.

Adult↗

Flow cytofluorimetry of fluorescein fluorescence polarization to assay lymphocyte activation.

Change in fluorescence polarization of intracellular fluorescein measured with a specially adapted flow cytometer reliably reflected subtle biophysical changes in cells, such as those accompanying increased temperature or osmolality of the suspending medium. This system was developed to monitor changes in lymphocytes one hour after stimulation with the mitogen phytohaemagglutinin, and provided a sensitive and rapid assay of lymphocyte activation.

Animals↗

Fluorescence polarization assay by flow cytometry.

Fluorescence polarization measurement on cell suspensions provides a highly sensitive means for detecting subtle changes in the cells, such as occur early after lymphocyte activation or on malignant transformation. We review here the principles of fluorescence polarization, its measurement by a commercially available flow cytometer and application of such assays especially in cellular immunology.

Animals↗

Changes in lymphocyte status and responsiveness in pregnancy detected by a fluorescent cell probe.

Lymphocyte reactivity assessed by a fluorescent lipophilic probe test of responsiveness to concanavalin A (con A) was shown to differ from normal in early pregnancy. The difference was most marked in multiparas. Abnormal reactivity was detected in the earliest pregnancy examined (5 weeks' gestation) and up to about the 20th week; after 20 weeks, reactivity was normal in all of the multiparas and most of the nulliparas studied. However, in pregnancy induced hypertension (PIH), a disorder of late pregnancy, the same responsiveness as in early pregnancy was found. When unstimulated lymphocytes were examined, abnormal reactivity associated with increased fluorescence was observed in early pregnancy and in PIH, compared with normal late pregnancy, reflecting alteration in lymphocyte membrane phospholipids. It is postulated that pregnancy is associated with sequential change in immunity, disturbance of which may result in immunologically-determined obstetric morbidity.

Adult↗

Lymphocyte subclasses in pregnancy induced hypertension.

Peripheral blood lymphocyte subclasses were studied by flow cytofluorimetry and monoclonal antibodies in 21 women with Pregnancy Induced Hypertension (PIH), 20 healthy women in their third trimester of pregnancy and in 20 nulliparous, nonpregnant women. The cells were stained with the monoclonal antibodies OKT3, OKT4 and OKT8 to define total T cells, T helper cells (Th) and T suppressor-cytotoxic cells (Ts/c) respectively. B lymphocytes were defined by their surface immunoglobulin. Absolute numbers of total T cells and Ts/c cells were significantly decreased (p less than 0.05) in patients with PIH compared to either control group. The proportion of B lymphocytes was significantly (p less than 0.01) increased and absolute numbers were marginally increased. These findings reflect an immune disturbance which may be of prime importance in the pathogenesis of this disease.

Adolescent↗

Significance of lymphocyte fluorescence polarization changes after phytohemagglutinin stimulation in cancer and noncancer conditions.

The double-zone fluorescein fluorescence polarization (FFP) "cancer" test was used to study 540 blood lymphocyte samples from 341 donors, of whom 158 had confirmed cancer: The other donors were noncancer patients, pregnant women, and normal individuals. The FFP response in cancer patients was the reverse of that in normal individuals, but an abnormal response was also obtained in some noncancer conditions, including the chronic inflammatory disorders--rheumatoid arthritis, cholecystitis, and diverticulitis--and in early pregnancy or pregnancy-induced hypertension. Thus the cancer discriminatory value of the test is limited. Examination of its biologic basis suggests that the positive FFP response in cancer and other conditions is due to altered immune status of blood lymphocytes, with associated change in cytoplasmic fluidity affecting the polarization of fluorescence. Incubation of normal blood lymphocytes with cyclic GMP induced an abnormal, cancer-like FFP response.

Cyclic AMP↗

Fluorescent probe assay of early mixed lymphocyte reaction to predict allograft survival in mice.

A rapid fluorescent probe assay of mixed lymphocyte reactivity has permitted prediction of allograft survival in mice. The assay is based on detection of early membrane events in stimulated cells by decreased fluorescence intensity of cell-bound N-phenyl-l-napthylamine (NPN) 30 min after allogenic cell interaction. The NPN-mixed-lymphocyte reaction (NPN-MLR) detected antigenic differences coded for by the whole H-2 complex or by the I region but not by the M locus. The probe assay correlated better with graft survival than did conventional 3H-thymidine assay, which also detects differences at the M locus that are less relevant to allograft rejection. Investigation of the cell types needed to obtain the response detected by the NPN-MLR assay revealed a requirement for mature T cells and plastic-surface-adherent monocytes and macrophages in the responding cell population. The monocytes and macrophages had an essential role in the generation of soluble factors that mediated the NPN-detected response. The NPN-MLR assay offers a reliable, rapid test of recipient-donor compatibility for allograft survival, and a system for studying early events in allogeneic cell interaction.

1-Naphthylamine↗

Lymphocyte fluorescence polarization changes after phytohemagglutinin stimulation in the diagnosis of colorectal carcinoma.

A lymphocyte fluorescence polarization test that measures reactivity to phytohemagglutinin (PHA) has permitted discrimination of a majority of patients with colorectal carcinoma from noncancer individuals. The test involves separation of two lymphocyte fractions from 20 ml venous blood on a modified leukocyte separation gradient, incubation with PHA for 45 minutes, addition of fluorescein diacetate, and analysis of change in fluorescence polarization. Of 19 colorectal patients tested preoperatively, 13 had a positive stimulation index, 3 a zero index, and 3 a negative index. Of 7 patients with other malignant neoplasms, a positive value was obtained in 6 and a negative value in 1. Of 14 patients with other diseases, a negative value was obtained in 9, zero in 3, and positive in 2. Of 31 normal donors a negative value was obtained in 27, zero in 2, and weak positive in 2. This rapid test promises to develop into a useful cancer-diagnostic method, and elucidation of its biological basis should identify a new cancer marker.

Adult↗