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Biomedical subjects

W Knapp

Publications and source records attributed to W Knapp.

At least 235 records · Page 13Linked to original sources

Suppressor cell activity in patients with rheumatoid arthritis.

Twenty-one patients with definite or classical rheumatoid arthritis (RA) were investigated for their suppressor cell activity by a Concanavalin A suppressor cell assay. Two patients had active disease, 9 moderately active disease, and 10 inactive disease according to clinical and laboratory parameters. A mean of 41 +/- 7% suppression was observed in RA patients as compared to 63 +/- 7% suppression observed in 10 healthy age and sex matched controls. No significant difference was observed between patients with moderately active or active disease (39 +/- 9%) and patients with inactive RA (43 +/- 10%). However, a borderline statistical significance (p = 0.05) was seen between controls and patients with moderately active or active RA. Use of autologous serum instead of AB serum for suppressor cell induction had no significant effect, although an increase of the mean suppression was noted (58 +/- 6%) in patient's group. No correlations existed between suppressor cell activity and presence of circulating Clq-binding immune complexes (solid-phase Clq assay), rheumatoid factor (Waaler-Rose test) or antinuclear antibodies (indirect immunofluorescence). This study indicates that lymphocytes of patients with inactive RA exert normal suppressor cell activity. It may well be that patients with active rheumatoid arthritis have decreased suppressor cell function. This will be assessed in a larger group of patients with active disease.

Adult↗

[Sugar composition of the lipopolysaccharide and ultrastructural study of the outer membrane of Yersinia enterocolitica (author's transl)].

Phenol-water-extracted lipopolysaccharide (LPS) from Yersinia enterocolitica (strain 75 in smooth form; O-group I), after growth at 10 degrees C, contains approximately 40% (w/w) 6-deoxy-L-altrose. By increasing the cultivation temperature a significant decrease in the O-specific sugar is observed. LPS from cells grown at 40 degrees C contains about 12% 6-deoxy-L-altrose. Thin-section micrographs of cells grown at lower temperatures reveal a distinct layer corresponding to the O-specific side chains of LPS in contrast to cells grown at higher temperatures where a decrease in thickness is observed. It is assumed that this observation is due to the decreasing amount of the O-specific sugar at a higher cultivation temperature. The results obtained by the indirect immunoferritin test indicate that the O-specific polysaccharide layer covers the cell surface completely up to 37 degrees C. However, this layer no longer covers the entire surface of all cells as soon as an incubation temperature of 40 degrees C is applied.

Antigen-Antibody Reactions↗

Influence of thymosin on E-rosette formation of lymphoid cells in leukemic and nonleukemic children.

The influence of two thymosin and two spleen control preparations on the E-rosette formation of peripheral blood lymphocytes and leukemic cells from non-leukemic children with depressed T cell values and leukemic children was investigated. Both thymosin preparations but also one of the control preparations induced a significant increase in the mean percentage of E-rosette forming PBL in the non-leukemic children with depressed T cell values. Thymosin and spleen preparations, however, did not convert the non-erythrocyte binding blasts to erythrocyte binding cells in either common or pre-T-ALL.

Child↗

[Acute enteritis with "new" pathogens. Yersinia infections (author's transl)].

Infections of the intestinal tract with Yersinia enterocolitica and Yersinia pseudotuberculosis are known the world over. Post-infection reactions like arthritis, erythema nodosum, erythema multiforme, scarlatiniform exanthemata and septicemic types deserve particular clinical attention. The clinical importance of enteric yersinioses has been shown in studies with the identification of significant antibody titers against Yersinia enterocolitis and Yersinia pseudotuberculosis in 6.71 and 4.58% respectively of 4411 patients examined for the first time. It was possible to isolate Yersinia enterocolitica from 5.05% of 616 samples of stool and Yersinia pseudotubercolosis from 0.66% of 136 lymph nodes taken from 751 patients.

Abdomen, Acute↗

MLC-activation by acute lymphatic leukemia blasts.

The MLC-activating potential of 25 ALL blasts (16 "common" ALL, 6 T-ALL, 3 not identified) was investigated. Mitomycin-treated leukemic blasts or X-irradiated lymphocytes were cultured with heparinized whole blood from different healthy donors. MLC activation by blast cells was expressed as percentage of MLC activation by X-irradiated lymphocytes. Leukemic blasts showed a heterogeneous pattern of MLC activation, ranging from 2% to 245%. Eleven out of 25 cases of ALL poorly stimulated the MLC (2% to 33% response). Twelve ALL stimulated a normal response (50% to 120%); and 2/25 ALL stimulated a supranormal response (more than 200%). Four of six cases of T-ALL stimulated the MLC as efficiently as irradiated lymphocytes, 2/6 were among the poor stimulators. Most poor stimulator blasts had, however, normal MLC-activating properties if, instead of whole blood, isolated lymphocytes were used as the responding cells. The poor activation of lymphocytes by some leukemic blasts in whole blood appeared to be associated with impaired release of blastogenic factor(s) during the MLBC. No evidence for active suppressor mechanisms was found. The significance of the MLC-activating properties of leukemic blasts for the classification and immunotherapeutic use of ALL is discussed.

Cells, Cultured↗

Studies on the use of membrane markers for the differential diagnosis of malignant lymphomas.

Lymphoid cells isolated from lymph nodes, spleen and the peripheral blood were examined using the rosette test with sheep erythrocytes (E), immunofluorescent staining of the surface immunoglobulins (SmIg) and the combined test (SmIg + E). The studies were performed on 48 patients with untreated non-Hodgkin lymphoma, 14 Hodgkin patients, 5 patients with lymphadenitis and on 132 controls. In the control group the following percentages of B-T lymphocytes were obtained: blood (n = 100); T-68 +/- 9, B-20 +/- 6, 0-11 +/- 7, BT-1 +/- 1, lymph nodes (n = 24): T-62 +/- 13, B-19 +/- 11, 0-18 +/- 8, BT-1 +/- 1, spleens (n = 8): T-45 +/- 9, B-33 +/- 9, 0-23 +/- 7, BT-1 +/- 1. In non-Hodgkin lymphoma lymph nodes a statistically significant increase of B and 'null' cells was noted in comparison to controls and to the Hodgkin lymphoma group. The characteristics of the Hodgkin nodes did not differ significantly from controls. After arranging the non-Hodgkin lymphomas according to the Kiel classification it was observed that the low-grade malignant lymphomas subtype most often an immunological 'B type' and 'mixed B/0' type was present whereas the high-grade malignant lymphoma group showed a distinct majority of 'null' cells. It was concluded that the surface markers studied allow a differentiation in most cases between the non-Hodgkin lymphomas and other disorders of the lymphoid system. They are not sufficient to distinguish the subtypes of non-Hodgkin lymphomas but do give interesting information about the more exact nature of the disorder.

B-Lymphocytes↗

[Clinical relevance of circulating immune complexes in patients with systemic lupus erythematosus and chronic polyarthritis].

Using a solid phase C1q assay, circulating immune complexes (IC) were detected in 15 of 55 patients with rheumatoid arthritis (RA) and 6 of 14 patients with systemic lupus erythematosus (SLE). In contrast to RA, presence of IC correlated to clinical disease activity in SLE patients. Preliminary short term follow up studies revealed additional differences between RA and SLE: whereas persistence of IC was noted in the patients with SLE, rapid changes of IC levels were observed in RA.

Arthritis, Rheumatoid↗

[Circulating immune complexes in patients with malignant diseases].

Circulating immune complexes were determined by a solid phase C1q assay in patients with divers malignancies. In Hodgkin's disease (n = 20), immune complexes were detected only in two patients during chemotherapy. Both patients succumbed shortly thereafter. In patients with testicular malignancies (n = 18), immune complexes were detected especially in patients without evidence of metastatic disease. Sequential investigations did not reveal prognostic insights. Summing up these data and the data obtained in additional patients with malignancies, it is interesting to note, that patients with carcinomas have a significant higher incidence of circulating immune complexes with malignancies of the lymphatic system. Our data, however, do not exclude presence of other than C1q binding immune complexes.

Hodgkin Disease↗

[Sézary syndrome. Clinical, immunological and proliferative kinetics].

The development of Sézary syndrome was observed in a patient with mycosis fungoides. The Sézary cells in the peripheral blood were identified as a specific T-cell population with helper cell characteristics. Autoradiographic analysis showed that the Sézary cells obtained from skin biopsies proliferated much more rapidly than those from the peripheral blood. After transformation into a highly malignant T-cell lymphoma (immunoblastic) it came to an abrupt and fatal course of the disease.

Aged↗

[Immunologic examination methods in dermatology diagnosis].

A survey is made of current usage of immunological test systems with regard to dermatology in general, and the practical importance of these techniques for the practizing dermatologist. Humoral and cellular immune systems are outlined; immunofluorescence, and determinations of cellular immune parameters are covered in more detail.

Antibody Formation↗

[Monocyte cytotoxicity in Hodgkin's disease].

Monocyte mediated antibody dependent cellular cytotoxicity (ADCC) was determined in 23 patients with Hodgkin's disease and 29 normal healthy controls. ADCC activity of monocytes was found to be significantly increased (p less than 0.01) in patients when compared to the controls. No significant difference was observed in the number of non specific esterase positive-monocytes in both groups of individuals, investigated. Thus increased ADCC activity of monocytes in Hodgkin's disease in this particular ADCC system is due to an increased lytic capacity of monocytes.

Adult↗

[In vitro testing of human lymphocytes (author's transl)].

The use of surface markers for the characterization of various lymphocyte subpopulation today belongs to the standard techniques of immunological laboratories. Recently, functional in vitro testing of human lymphocytes has met with increasing interest. In this paper some of the relevant in vitro test systems such as the lymphocyte stimulation test, the determination of the B cell differentiation capacity in vitro and the demonstration of suppressor cell activity are discussed. Apart from a discussion of the results obtained by these techniques in normal, healthy individuals, the applicability of these techniques for studies in patients is dealt with.

B-Lymphocytes↗

Receptors for IgM on human B lymphocytes.

Using a rosette technique with IgM coated bovine red blood cells (EA-IgM) receptors for IgM can be demonstrated on human B-lymphocytes. While in the peripheral blood B cells with IgM receptors are found only occasionally, between 7 and 33%, mean 16%, of tonsil B-lymphocytes exhibit receptors for IgM. This was shown in double marker studies using EA-IgM for the demonstration of IgM receptors and fluorochrome labelled conjugates for the demonstration of S-IgD, S-IgM and B cell antigens. These receptors are specific for IgM, they can be completely blocked by IgM-anti OVA complexes and partially by free IgM, but not at all by aggregated human IgG. They are sensitive to trypsin and pronase but reconstitute after further incubation at 37 degrees C. These data show that not only T and CLL cells but also some normal B-lymphocytes have receptors for IgM. We favour the view that CLL lymphocytes may derive from these B-lymphocytes, which may represent a certain maturation step in B cell development.

Antigens↗

Studies on rosette formation of human lymphocytes with pig red blood cells.

In this paper, data are presented which indicate that receptors of human peripheral blood lymphocytes (PBL) for pig erythrocytes (PRBC) and sheep erythrocytes (SRBC) are identical or at least very similar to each other with a higher avidity of PBL for SRBC than for PRBC. As an average, 50 +/- 9% of human PBL formed PRBC rosettes (Ep), compared to 70 +/- 7% of SRBC rosettes (Es). Lymphocytes incubated with SRBC plus PRBC ('co-rosetting') formed 10 +/- 5% of mixed rosettes (Em) but no pure Ep. Resuspension of rosetted lymphocytes followed by co-rosetting with the other erythrocyte species revealed that the majority of Ep became Em, while the majority of Es remained pure Es even after co-rosetting with PRCB; no pure Ep was newly formed. Incubation at 37 degrees C abolished almost all Ep as compared to 9% Es. Anti-thymocyte serum inhibited both types of rosette formation. PBL from patients with chronic lymphatic leukemia formed only 2.5 +/- 2.5% Ep. 1.7 +/- 1.1% of PBL expressed both membranes immunoglobulins and receptors for PRBC. Trypsin treatment abolished both kinds of rosette formation almost completely, while neuraminidase treatment of erythrocytes led to a raise in Ep formation from a mean of 53% to a mean percentage of 68%. Electron microscopic investigations did not reveal differences between binding sites of lymphocytes for PRCB and those for SRBC; however, with a technique different from the conventional one, intimate contact areas were observed between lymphocytes and both kinds of red blood cells.

Animals↗

[Cellular immune reactivity in patients with multiple myeloma].

The ConA-, PHA- and PWM-induced lymphocyte transformation rates were significantly decreased in 19 patients with multiple myeloma. Lymphocyte-inherent defects rather than serum factors seem to account for this decreased lymphocyte reactivity. In 58% of the patients a pathologically increased ConA-induced suppressor cell activity, which was negatively correlated with the non-paraprotein IgM-concentration, was found.

Humans↗