Search PubMedSearch

Biomedical subjects

V Andersen

Publications and source records attributed to V Andersen.

At least 55 records · Page 3Linked to original sources

Interleukin 2 augmentation of the defective natural killer cell activity in patients with primary Sjögren's syndrome.

Natural Killer (NK) cell activity against K562 target cells was measured in 21 female patients with primary Sjögren's syndrome (primary SS) and in 20 female normal controls matched for age. The in vitro effect of alpha-interferon (IF) and interleukin 2 (IL-2) on NK cell activity was examined and the percentage of large granular lymphocytes (LGL) in blood was measured. Median baseline NK cell activity in primary SS was 15.4% versus 24.4% in the controls (P less than 0.05). Median IF-enhanced NK cell activity in the SS group was 35.5% versus 49.6% in the controls (P less than 0.02). IL-2-enhanced NK cell activity was 35.5% versus 37.6% in the controls (n.s.) The proportion of LGL did not differ in the two groups. Median LGL/lymphocytes was 4.0% in the primary SS patients versus 4.5% in the controls (n.s.). We conclude that the defective NK cell activity in patients with primary SS is functional, as the number of LGL is normal. Further the NK cell activity off SS was restored by IL-2.

Adult

Sézary syndrome: phenotypic and functional characterization of the neoplastic cells.

Phenotypic properties of the neoplastic cells in skin, blood and lymph node specimens from 5 patients with the Sézary syndrome were examined by immuno-enzymatic and -fluorescence labelling of cells and tissue sections with a monoclonal antibody panel. In 3 cases, the in vitro functional properties of the neoplastic cells (isolated from blood specimens) were also analysed using a reverse plaque-forming cell assay. 3 different immunological categories were identified as follows: T-helper/inducer neoplasms (3 patients); T-suppressor/cytotoxic neoplasms (1 patient); and neoplastic T-cells demonstrating characteristics consistent with a concept of their derivation from inducible suppressor T-cells (1 patient). These data provide conclusive evidence that Sézary syndrome is heterogeneous with respect to the immunological characteristics of the neoplastic cells.

Aged

Induction of immunoglobulin secretion in cultured human lymphocytes by 4 Staphylococcus aureus strains and their extracts.

Human blood lymphocytes were stimulated in vitro by four Staphylococcus aureus strains. Activation of immunoglobulin-secreting cells was determined by a reverse plaque forming cell (PFC) assay, and proliferation by quantitation of thymidine incorporation. Whole killed S. aureus were slightly more efficient than water-soluble preparations in the form of sonicated extracts and culture supernatants. Two S. aureus strains rich in protein A (Cowan I and E 2371) and one S. aureus strain deficient in protein A (E 1369) were potent B-lymphocyte stimulators inducing maximal activity on day 6 of culture. Another S. aureus strain deficient in protein A (Wood 46) did not possess++ human lymphocyte stimulating capacity.

Hemolytic Plaque Technique

Interaction of human IgG preparations with polymorphonuclear leukocytes in vitro.

The effect of purified human immunoglobulin G, prepared for intravenous administration by polyethylene glycol precipitation and ion exchange chromatography, on polymorphonuclear leukocytes (PMN) in vitro was studied. IgG induced a dose-dependent stimulation of the oxidative metabolism of the cells, as measured by release of superoxide anion and by chemiluminescence. The lowest concentration giving a detectable effect was 0.001 mg/ml. Two commercially available preparations of IgG for clinical intravenous use caused similar stimulation of the PMN although they differ in methods of isolation and purification. The addition of 10% maltose markedly reduced the stimulation by all three preparations of IgG. We suggest that i.v. infusion of purified IgG may lead to activation in vivo of host phagocytic cells without participation of complement, and that this interaction may be responsible for the hitherto unexplained side-effects caused by i.v. infusion of such preparations.

Energy Metabolism

Spontaneous in vitro immunoglobulin secretion at the diagnosis of insulin-dependent diabetes.

Blood mononuclear cells obtained from 17 newly diagnosed insulin-dependent diabetic (IDDM) patients treated with insulin for 5-7 days were assessed for the number of spontaneous and pokeweed mitogen (PWM)-stimulated immunoglobulin-secreting cells in a reverse haemolytic plaque assay. The spontaneous in vitro immunoglobulin secretion was evanescent and decreased in individual patients within 1-4 months of insulin treatment. Compared to matched controls, 53% (9/17) of the IDDM patients had an elevated spontaneous secretion of immunoglobulin, 41% (7/17) for IgG, 35% (6/17) for IgM, and 35% (6/17) for IgA. The quantities of PWM-stimulated IgG, IgM, or IgA secreting cells in IDDM were comparable to the controls. The IDDM patients with spontaneous immunoglobulin secreting cells had higher fasting C-peptide levels compared to the patients with immunoglobulin-producing cells within the normal range (P less than 0.05). The average titre of islet cell cytoplasmic antibodies was 1:26 in (9 out of 9 were positive) patients with, compared to 1:1 in patients (4 out of 8 were positive) without spontaneous secretion (P = 0.025). These results suggest that the clinical onset of IDDM is associated with a polyclonal B lymphocyte activation and that higher levels of fasting C-peptide islet cell antibodies are associated with this immunoregulatory abnormality.

Adolescent

Storage of protein A-conjugated sheep erythrocytes for use in plaque-forming cell (PFC) assays.

Sheep red blood cells conjugated with protein A from Staphylococcus aureus were frozen in liquid nitrogen. After thawing these cells were used as indicator cells in a plaque-forming cell assay visualizing human B lymphocytes secreting IgG, IgM or IgA. The thawed erythrocytes performed as well in the assay as erythrocytes freshly conjugated with protein A. Recovery of conjugated erythrocytes after freezing and thawing averaged 66%. By the method described indicator cells for a number of PFC assays may be prepared in bulk, frozen in suitable portions and thawed when needed. This prevents possible batch-to-batch variations and saves time.

Animals

Lymphocyte function and chromosome aberrations in patients with early mycosis fungoides and parapsoriasis en plaques.

Thirteen patients with stage I or II mycosis fungoides (MF) and 10 patients with large-plaque parapsoriasis en plaques (PEP) were examined for immunologic and cytogenetic disturbances. Total lymphocyte counts and immunoglobulin concentrations in the blood were normal. In vitro lymphocyte responses to polyclonal activators and various antigens in standard concentrations were normal. However, titration of phytohemagglutinin and concanavalin A (ConA) disclosed significantly lowered responses to suboptimal concentrations in the patient group, most pronounced in patients with MF II. ConA-induced leukocyte migration inhibitory factor (LIF) production, tested in an indirect leukocyte migration inhibitory assay, was low in the patient group. Furthermore spontaneous LIF production in vitro and small amounts of serum LIF were demonstrated in a few patients. The chromosomal banding pattern, sister chromatid exchange, and break frequency were within normal limits except for 3 translocations in the MF group. It is concluded that even in early-stage MF a pathologic function of blood lymphocytes can be demonstrated, when sensitive methods are applied. The findings might be important for monitoring disease activity and effect of treatment.

Adult

Immunological studies in two children with recurrent parotitis.

In two children with recurrent parotitis, labial salivary gland biopsies showed chronic sialoadenitis. Immunofluorescence studies disclosed deposits of immunoglobulins and complement in juxta-acinar small vessels. Case 1 had gluten enteropathy, IgA deficiency and high titres of antinuclear antibodies (ANA), and in vivo fixation of ANA to nuclei of different cells in lip, skin and jejunum was present. Case 2 showed deposition of IgM in the dermo-epidermal junction of the skin. These findings suggest that autoimmune reactivity and immune complexes may play a role in the pathogenesis of this disorder.

Adolescent

Suppression of B lymphocytes in mature newborn infants.

The ability of cord blood lymphocytes to secrete immunoglobulins during in vitro culture was investigated by means of a reverse hemolytic plaque forming cell (PFC) assay. Mononuclear cord blood cells did not differentiate into immunoglobulin-secreting cells after stimulation with the polyclonal B lymphocyte activator pokeweed mitogen (PWM), contrary to the findings in normal adults. Mononuclear cord blood cells were then separated into T-enriched and T-depleted blood lymphocyte subsets. When these were co-cultured, the PWM-induced immunoglobulin secretion was still low; following irradiation of the T-enriched cells, the numbers of IgM-PFC but not of IgG- or IgA-PFC increased considerably. The effect of irradiation of the T-enriched cells on the PWM-induced IgM response was dose-dependent, with maximal effect at 2500 rad. It is concluded that the low PWM responses obtained using cord blood lymphocytes are in part due to suppression by radiosensitive T suppressor cells. Following removal of this suppression by means of irradiation, B lymphocytes can be induced to secrete IgM, but not IgG or IgA.

Adult