bluuebunny/crossref_metadata_2025 huggingface dataset:
Umbilical‐Cord‐Blood‐Derived Suppressor Cells of the Human Natural Killer Cell Activity Are Inhibited by Interferon
Authors: TARKKANEN J. , SAKSELA E.
Published: June 2006

The natural killer (NK) activity of umbilical‐cord‐derived lymphocytes was studied. The general level of activity was lower than with adult lymphocytes against K‐562 cells and fetal fibroblasts. The activity could be boosted by interferon pretreatment of effector cells, but not to the same extent as with adult lymphocytes. Umbilical cord lymphocytes were fractionated with Percoll density gradient centrifugation, and the suppressive activity of different fractions was tested on highly enriched adult buffy‐coat‐derived NK cells. Allogeneic adult NK cell activity could be inhibited in 9 of 20 cases tested with small and medium‐sized T lymphocytes (Percoll fractions 4–5) from the umbilical cord. The suppressive capacity was further enriched in fractions forming rosettes (RFC) with antibody‐coated human erythrocytes (EA). Such EA‐RFC of Percoll fractions 4–5 from umbilical cord exerted a strong suppressive activity in each case tested. Pretreatment of EA‐RFC with interferon regularly abolished the suppressive effect. We conclude that there are Fc‐receptor‐positive small/medium‐sized T lymphocytes in the umbilical cord blood which can efficiently suppress the cytotoxic activity of NK cells and that the suppressive activity can be abolished by interferon pretreatment of the suppressor cells.
The Influence of Antigen Density and a Comparison of IgG and IgM Antibodies in the Anti‐Complementary Modulation of Lymphocytic Surface Immunoglobulin
Authors: GORDON J. , ANDERSON V. A. , ROBINSON D. S. F. , STEVENSON G. T.
Published: June 2006

Experiments were carried out to determine the influence of antigen density on anti‐complementary modulation, defined here as the conferring by anti‐immunoglobulin (Ig) of resistance to lysis of guinea pig L2C leukaemic lymphocytes through anti‐Ig plus syngeneic complement (C). Populations of leukaemic cells, varied widely in their quantitative expression of surface membrane Ig as judged by the binding to cells of 125I‐labelled Fab’ fragments from anti‐Ig, and a good correlation between the bulk antigen density and the percentage of cells lysed by anti‐Ig plus C was obtained (P=0.02). In the presence of 10mm sodium azide, which has been shown to diminish ihe modulation occuring during simultaneous incubations with anti‐Ig and C, this correlation was even stronger (P < 0.001). No zone could be defined in which the level of surface Ig expression was sufficient to serve complement lysis but too low for modulation. Furthermore, both the degrees and rates of modulation occurring on incubation with antibody at 37°C, either before C addition or in the presenee of lytic C, were similar for populations of high, low, or intermediate antigen density. Separation of cells by their size or density failed to yield populations differing in either their susceptibility to humoral killing through anti‐Ig or their modulating capacity. IgG and IgM antibodies to the L2C cell surfce Ig evoked similar levels of killing with syngeneic C, and when compared for their ability to promote anti‐complementary modulation, no difference was revealed in either the rule or degree of modulation occurring during incubations at 37°C with the two isotypes. The findings are discussed with particular reference to observations on the modulation of mouse thymus leukaemia (TL) antigens.
Purification of the Synaptic Membrane Glycoprotein D2 from Rat Brain
Authors: RASMUSSEN S. , RAMLAU J. , AXELSEN N. H. , BOCK E.
Published: June 2006

D2 is a nervous‐specific membrane protein enriched in fractions of synaptosomal membranes from rat brain. Recently, an immunochemical relationship between D2 and the chick cell adhesion molecule (CAM) has been demonstrated. There is reason to believe thai D2 is involved in adhesion phenomena between neurites. The purpose of the present study was to purify and further characterize the D2 protein from rat brain. In the developed purification procedure synaptosomal membranes from rat brains were prepared and solubilized by means of non‐ionic detergent. The subsequent purification steps were hyroxylapatite chromatography, wheat germ lcctin affinity chromatography, gel filtration, and lysine affinity chromatography. The purified D2 was found to be enriched 240 times compared with the starting brain homogenate and 120 times compared with the synaptosomal membrane fraction. The recovery of D2 was 26% when the amount of D2 in ihe synaptosomal membrane fraction was set to 100%. The purified D2 antigen was used for production of monospecific rabbit anlisera, and it was found to be composed of two polypeptides of apparent molecular weights 130,000 and 150,000, respectively.
Enhancement of Human B Lymphocyte Differentiation in Vitro by Thyroid Hormone
Authors: PAAVONEN T.
Published: June 2006

A study was made of the regulatory influence of a thyroid hormone, triiodothyronine (T3), on human blood T‐ and B‐lymphocyte responses in vitro. Blood lymphocytes were stimulated with the T‐cell mitogens concanavalin A (Con A) and phytohaemagglutinin (PHA), with the T‐dependent B‐cell activator pokeweed mitogen (PWM), and with the T‐independ‐ent B‐cell activator Staphylococcus aureus Cowan I bacteria in the presence of various hormone concentrations. T3 did not stimulate T‐cell proliferation. The number of immuno‐globulin‐containing and ‐secreting cells (plasmablasts) was increased in PWM and Staph. aureus cultures treated with T3. The maximal enhancement was reached at a concentration of 10−9‐10−7 M T3. Cell fractionation techniques revealed that T3 apparently had a direct stimulatory effect on B‐cell differentiation.
Augmented Numbers of HLA‐DR‐Positive T Lymphocytes in the Synovial Fluid and Synovial Tissue of Patients with Rheumatoid Arthritis and Juvenile Rheumatoid Arthritis
Authors: FØRRE Ø. , DOBLOUG J. H. , NATVIG J. B.
Published: June 2006

Twenty to 40 % of T cells from synovial fluid and synovial tissue and 3–11 % of the peripheral blood T lymphocytes from patients with rheumatoid arthritis (RA) and juvenile rheumatoid arthritis (JRA) expressed HLA‐DR antigens as detected by monoclonal anti‐HLA‐DR antibodies in direct immunofluorescence. Synovial fluid and synovial tissue T lymphocytes had a stimulating capacity comparable to that of non‐T cells in the allogeneic primary mixed lymphocyte reaction (MLR). The MLR was inhibited by monoclonal anti‐HLA‐DR antibodies. This is, to our knowledge, the first report on in‐vivo‐activated T lymphocytes as stimulator cells in MLR. The results suggest that T cells from synovial fluid and synovial tissue are locally activated by stimuli so far unidentified.
Pigment Mutations in the Mouse Which Also Affect Lysosomal Functions Lead to Suppressed Natural Killer Cell Activity
Authors: ÖRN A. , HÅKANSSON E. M. , GIDLUND M. , RAMSTEDT U. , AXBERG I. , WIGZELL H. , LUNDIN L.‐G.
Published: June 2006

The impact of five pigment mutations in the mouse on natural killer (NK) activity was examined in inbred strains congenic for the respective mutation. Whereas the nature of pigmentation disorder was similar in the five mutant strains (beige, pallid, reduced pigmentation, pale ear, and sepia), all mutations except sepia also led to a significant change in lysosomal enzyme activities in the kidney. A significant reduction in NK activity was observed in the four strains with lysosomal impact, whereas homozygous sepia mice displayed normal NK activity. The pigment mutations analysed are located on different chromosomes and fail to cross‐interact negatively with each other in the heterozygous mice. This would indicate that pigment mutations with a parallel impact on lysosomal enzyme activities probably always result in a reduction in natural killer cell activity.
Chain Structure of Cobra Venom Factor from Naja naja and Naja haje venom
Authors: VON ZABERN I. , PRZYKLENK H. , VOGT W.
Published: June 2006

The chain structure of cobra venom factor, whether isolated from Naja naja venom (CVFn) or from Naja haje venom (CVFh), is similar. Both homologous proteins are composed of three disulphide‐linked chains (A, B, and C) with apparent molecular weights of 72,000, 54,000, and 27,000–35,000 for CVFn and 68,000, 51,000, and 30,000–32,000 for CVFh. That all three polypeptides are integral parts of CVF was demonstrated by investigation of the chain pattern after partial reduction. Reduction with 1–2 mM dithiothreitol under nondenaturing conditions yielded free B‐chain, together with an intermediate product composed of disulphide‐linked A‐ and C‐chains. The C‐chain was heterogenous when investigated by electrophoresis in polyacrylamide slab gels in the presence of SDS. Similarly, isoelectric focusing of CVFn and CVFh showed a multiplicity of bands in the pH range 5.2–6.4. Limited tryptic digestion resulted primarily in the fragmentation of the B‐chain. CVFh is much more sensitive to tryptic attack than CVFn. In all our preparations of CVFh a partial, trypsin‐like fragmentation of the B‐chain was detectable to various extents.
Leucocyte‐Associated Plasma Proteins
Authors: ANDERSEN M. M.
Published: June 2006

Sixteen plasma proteins were studied in the supernatants from 20 successive washings of human leucocytes by a new sensitive immunoelectropharetic method. In the first few supernatants u fast and parallel decrease in concentration of all proteins look place, but for 11 proteins this was followed by a phase of slow decrease due to cellular release. Eight proteins could be quantitated throughout the 20 washings: prealbumin, albumin, orosomucoid, α1‐antitrypsin, transferrin, C3, haptoglobin, and IgG. These proteins and trace amounts of eight other plasma proteins were present in the cell lysate after the washings. In comparison with plasma, the leucocytes contained relatively higher concentrations of prealbumin, orosomucoid, α1‐antitrypsin, and haptoglobin than of albumin. In crossed immunoelcctrophoresis these same four proteins were present as molecular variants differing from their plasma counterpart in elcetrophoretic mobility and morphology of the precipitate.
The Use of Lysostaphin in in Vitro Assays of Phagocyte Function: Adherence to and Penetration into Granulocytes
Authors: VAN DEN BROEK P. J. , DEHUE F. A. M. , LEIJH P. C J. , VAN DEN BARSELAAR M. TH. , VAN FURTH R.
Published: June 2006

The usefulness of lysostaphin for the removal of cell‐adherent and extracellular bacteria in assays performed to measure the intracellular killing of Straphylococcus aureus by granulocytes was investigated. The results showed that the adherence of lysosiaphin to the granulocyte surface is effectuated by a temperature‐independent process and that bound lysostaphin is still microbicidal. Lysosiaphin also penetrates into the granulocytes by a temperature dependent process and kills ingested S. aureus intracellularly. Therefore, despite reports to the contrary in the literature, lysosiaphin is not a reliable agent for the removal of only extracellular S. aureus and should no longer be used in assays to determine the rate of intracellular killing by granulocytes.
Natural and Antibody‐Dependent Cellular Cytotoxicity in Tumour‐Adherent T Lymphocytes: Expression of Fc Receptors and of a Human T‐Subgroup‐Specific Antigen
Authors: FEUCHT H. E. , HADAM M. R. , LOHMEYER J. , FRANK F. , RIEBER E. P. , RIETHMÜLLER G.
Published: June 2006

Adherence of human lymphocytes to allogeneic tumour cell monolayers was found to depend on the presence of monocytes. Adherent lymphocytes could lie separated from tumour cells by treatment with lidocaine followed by nylon wool passage. Tumour‐adherent cells (70% E‐RFC, 45% Fcγ‐R, 23% Fcμ‐R, 5% monocytes) exhibited enriched natural killer (NK) activity not only against the tumour cell line used for isolation but also against seven other targets. When T cells were isolated subsequently as E‐rosettes by density gradient centrifugation through Percoll, the enrichment in cytotoxicity was even more pronounced. Tumour‐adherent T cells were severalfold enriched in both N K and antibody‐dependent cell‐mediated cytotoxicity (ADCC) activity. However, this enrichment was not paralleled by a concomitant increase in the number of Tγ cells (tumour‐adherent T cells: 17% Tγ, 40% Tμ: tumour‐nonadherent T cells: 12% Tγ, 60% Tμ). Marked differences could be observed by staining with a monoclonal antibody that was raised against human leukaemic Tγ cells of high NK and ADCC activity. This antibody (T8–11) stained 60% of tumour‐adherent T cells. 20% of nonadherent T cells and 29% of T‐cell controls. These results indicate that the spontaneous cyloloxic activity of human T cells resides within a small population, most of which are characterized by a specific surface antigen but not by conventional Fcγ receptors.
One Third of Murine Splenic T Cells Are Cytotoxic Precursors Induced to Grow by Leucoagglutinin and TCGF
Authors: LARSSON E.‐L.
Published: June 2006

The frequency of leucoagglutinin (LA)‐inducible, TCGF‐reactive T cells has bcen determined using a sensitive limiting‐dilution assay. The f'rcqucncy of cells proliferating in TCGF‐CM was 1 in 3. and the Frequency of lectin‐dependent cytotoxic T lymphocyte precursors (CTL‐p) was 1 in 3–4. By analysing individual clonal cultures for proliferation and cytotoxic potential, a selective induction nf CTL‐p was detected, as all prolifcrating clones were found to mediate lectin‐dependent cytotoxicity.
Studies on Mouse Auto‐reactive Cells
Authors: CHARREIRE J. , BACH J. F.
Published: June 2006

In mice, an in vitro cell‐mediated cytotoxicity is directed towards syngeneic erythrocytes used as targets. This phenomenon occurs in lymphoid organs of normal, non‐immunized mice. Its intensity is greater in the thymus than in spleen or lymph nodes. The study of the nature of the cell responsible for this spontaneous syngeneic cytotoxicity ruled out the role of macrophages. The involvement of T cells in this phenomenon is assessed by its disappearance after the lymphoid celts had been treated with anti‐theta serum plus complement, by its disappearance from lymphoid organs of mice previously treated by hydrocortisone, and by its decrease in the presence of synthetic thymic factor. Moreover, spontaneous syngeneic cytotoxicily is lost when lymphoid cells are depleted of autologous rosettes by centrifugation on a Ficoll‐Hypaque gradient after rosette formation. Cytotoxic lymphocytes might belong to the population of auto‐rosettes previously characterized as a population of immature T cells.
Two Distinct Fc Receptors for IgG on Human Peripheral T Lymphocytes
Authors: SAAL J. G. , HADAM M. R. , FEUCHT H. E. , RAUTENSTRAUCH H.
Published: June 2006

The proportion of human peripheral T lymphocytes forming rosettes with IgG‐coated ox erythrocytes (ORBC) is increased after controlled hypotonie treatment. This increment may be as high as 40% of total T cells, depending on the lymphocyte donor. Such treatment is shown not to result in selective cell loss. Induced rosetting is mediated by a receptor specific for the Fc portion of human IgG (FcγR). Inhibition of induced FcγR activity is equally well accomplished by monomeric and by aggregated IgG of defined size. This is in contrast to the FcγR detected before hypotonie treatment, which is not significantly inhibited by monomeric IgG. Capping studies establish the structural independence of these two types of FcγR in the lymphocyte membrane by virtue of selective cross‐linking of cither receptor while leaving the respective counterpart unaffected. The biochemical basis of the hypotonie effect is not yet resolved. However, the data presented suggest that hypotonicity results in removal of FcγR‐bound cytophilic IgG. Operationally, we propose the term induced FcγR (FcγR‐I) for the here‐described new type of receptor with high affinity for monomeric IgG. FcγR that are directly assayable without hypotonie induction and not inhibited by monomeric IgG are termed free FcγR (FcγR‐F).
A Study of CSF Idiotypes in Multiple Sclerosis
Authors: EBERS G. C.
Published: June 2006

Six ant‐idiotypic antisera have been raised against isolated cerebrospinal fluid (CSF) bands from five patients with multiple sclerosis and against a serum band from an additional patient. Preparative isoelectric focusing in agarose was useful for isolating highly purified bands. Individual antigenic specificities defined by these antisera were not delected on other bands from the same patients or in IgG isolated from the CSF of other patients. The CSF to serum ratios of the idiotypic determinants ranged from 1:2 to 1:8, consistent with substantial local synthesis in the central nervous system; the higher concentration in serum suggests that initial clonal expansion of antibody‐making cells may have occurred outside the nervous system. An anti‐idiotypic antiserum raised against the dominant band from postmortem CSF was used to compare the levels of idiotypic IgG eluted from four plaque areas. Although the amount of IgG eluted from each differed, the concentration of idiotype was similar for all plaques tested. The interaction of anti‐idiotype with idiotype could not be inhibited by saline extracts of normal or multiple sclerosis brain.
Lymphoid Cell Lines as Indicators of Lymphokine Generation
Authors: CULBERT E. J. , COCHRAN A. J. , CLEMENTS G. B.
Published: June 2006

We investigated the migration characteristics of the cells of four human lymphoid lines, normal peripheral blood leucocytes (PBL), and normal mouse splenocytes (MSC). Two lines (QIMR‐WIL and Namalwa) were actively migratory, as were the PBL and MSC. Migration was inhibited at low temperatures and reduced by inhibitors of glycolysis, oxidative phosphorylation and RNA synthesis. The migration of QIMR‐WIL cells, PBL and MSC but not Namalwa was inhibited by lymphokine‐containing supernatants from phytohaemagglutinin‐pulsed MSC or MSC stimulated by allogeneic cells. The inhibitor of migration in the supernatants had properties similar to those of human leucocyte inhibition factor but distinct from those of macrophage inhibition factor. QIMR‐WIL and normal human PBL were compared as indicators in an indirect leucocyte migration assay. QIMR‐ WIL cells were the more sensitive responder cells and are an abundant, stable, and uniform cell population for lymphokine detection.
Mechanisms Involved in Age‐dependent Decline of Immune Responsiveness and Apparent Resistance against Tolerance Induction in C57BL/6 Mice
Authors: AMAGAI T. , NAKANO K. , CINADER B.
Published: June 2006

The plaque‐forming antibody response of C57BL/6 mice to rabbit gamma globulin (RGG) decreases as a function of age. RGG in tolerogenic form induces tolerance of young mice but sensitizes older animals. If antigen is administered together with lipopolysaccharide, the age‐dependent decline in immune responsiveness is not observed, nor are older animals sensitized by tolerogen. The age‐dependent decline in immune responsiveness is due to a less of T helper capacity; sensitization by tolerogen is attributable to a subpopulation of B cells which becomes sensitized by the tolerogen. Older animals, treated with tolerogen, show a degree of central tolerance of T cells and a relatively slight, age‐dependent diminution in colchicine‐ or cyclophosphamide‐sensitive precursors of suppressor cells.
Density Distribution Profiles of T Cells: TM, TG and TA Cells and Response Patterns in Autologous Versus Allogeneic MLRs
Authors: CANONICA G. W. , KABELITZ D. , SJÖBERG O. , AIGRAIN Y. , WIGZELL H.
Published: June 2006

Discontinuous Percoll gradients have been used to obtain selected humanperipheral blood T lymphocytes without having to resort to interactions with immune complexes in the fractionation of TM, TG and TA cells. Here, we could show that TA cells represent a heterogeneous population with no distinct density profile, in contrast to light(TG) and heavy (TM) cells. Enriched, heavy TM cells could be shown to be excellent responders in allogeneic MLR while failing to react in autologous MLR In contrast, T cells of light density preferentially respond in autologous compared with allogeneic MLR.
Characteristics of the Amyloid A Fibril‐Degrading Activity of Human Serum
Authors: TEPPO A.‐M. , MAURY C. P. J. , WEGELIUS O.
Published: June 2006

Radial diffusion in agarose gel containing amyloid A (AA) fibrils was used to study the scrum enzyme capable of degrading AA fibrils in vitro. This degradative activity was unaffected by soya bean trypsin inhibitor, tosyl‐lysine chloromethyl ketone, and gold thiomalale but was inhibited by bovine pancreatic trypsin inhibitor, phenylmethylsulphonylfluoride, diisopropyl fluorophosphate, α1‐antitrypsin, and α2‐macroglobulin, indicating that the enzyme involved is a serine protease. Agarose gel electrophoresis showed the enzyme to be an acidic protein with the same electrophoretic mobility as albumin, The molecular weight, measured by gel filtration, was approximately 50,000. The optimum pH of this enzyme was 7.3, and it was fairly heat‐resistant. The results suggest that the AA‐fibril‐degrading activity in human serum is due neither to elastase nor to cathepsin G. It has many characteristics in common with the enzymes unlike elastasu that are involved in the complete degradation of serum AA protein.
Immunoglobulins in Rabbit Hepatic Bile: Selective Secretion of IgA and IgM and Active Plasma‐to‐Bile Transfer of Polymeric IgA
Authors: DELACROIX D. L. , DENEF A. M. , ACOSTA G. A. , MONTGOMERY P. C. , VAERMAN J. P.
Published: June 2006

Proteins in hepatic bile from cannulated rabbits were analysed by gel filtration, electrophoresis, density gradient ultracentrifugation, and immunochemical methods. Bile‐to‐serum concentration ratios (no.=8) demonstrated that IgA and free secretory component (SC) were major constituents of rabbit bile. Relative concentration ratios, obtained by dividing the bile to serum level ratio tor each protein by the corresponding ratio for albumin, were 310, 1.6, 1.0, 0.82, and 0.54 for IgA, IgM, albumin, transferrin, and IgG respectively, suggesting that both IgA and IgM are selectively secreted into bile. Ligation of the bile duct (no.= 5) led to a selective increase of the serum levels of IgA and SC, the latter as secretory IgA. After intravenous injection (no.= 4) of human polymeric IgA, 37‐69% of the injected dose was recovered in bile after 3 h, in contrast lo 4–5% for human monomeric IgA. The active transfer of both rabbit and human polymeric IgA into rabbit bile occurs via the same hepatic SC‐mediated transport process as that described for the rat.
In Vitro Cytotoxicity of Mouse Macrophages Activated by Coculture with Syngeneic Sarcoma Cells
Authors: OLSTAD R. , KAPLAN G. , SELJELID R.
Published: June 2006

Normal resident peritoneal macrophages from C3D2(C3H/Tif × DBA/2) F1mice were activated in vitro by culturing with semisyngcneic tumour celts. The tumour cells originated from a methylcholanthrene‐induced sarcoma (MCIM) growing in vivo in ascites form. Macrophagc‐mediated cytotoxicity was evaluated after 5 days of in vitro culture, using five different target cells. Semisyngencic (L 929), allogeneic (B16 melanoma), and xcnogeneic (HeLa) tumour cell lines and normal allogencic tibroblast cell lines (3T3, 3T6) were tested. The morphology and kinetics of the cytotoxicity reaction were studied by scanning electron microscopy and compared with release of radioactivity from14C‐thymidine‐labelled target cells. The activated macrophages were able to kill the semisyngeneic, allogeneic, and xenogeneic tumour cell lines tested under conditions that did not affect normal fibroblasis. The requirement for T cells during activation of the macrophages was also tested. The cyioioxicity decreased markedly when T cells were removed from the macrophage cultures before activation or when macrophages from nude mice were used in the experiments.
Enhancement of Murine Immune Responses to Orally Administered Haptenated Streptococcus mutans
Authors: KIYONO H. , MICHALEK S. M. , MOSTELLER L. M. , TORII M. , HAMADA S. , McGHEE J. R.
Published: June 2006

The induction of immune responses to orally administered trinitrophenyl (TNP)‐haptenated Streptococcus mutans and its enhancement with muramyldipeptide (MDP), peplidoglycan (PG), and concanavalin A (Con A) were investigated in lipopolysaccharide (LPS)‐non‐responsive C3H/HeJ mice and the syngencic, UPS‐responsive C3H/HeN strain. Both mouse strains manifested similar immune responses, primarily of the IgM isotype, after a single gastric intubation (GI) with TNP‐S. mutans. However, when groups of animals were first carrier‐primed by GI with S. mutans for 2 consecutive days, followed by a single GI with TNP‐S. mutans I week later, C3H/HeJ mice gave a significantly higher (P 0.01) splenic IgA anti‐TNP plaque‐forming cell (PFC) response than identically treated C3H/HeN mice. Furthermore, saliva, urine and serum from these C3H/HeJ mice possessed high levels of IgA anti‐TNP antibodies as determined by the enzyme‐linked immunosorbent assay, whereas C3H/HeN mice exhibited low antibody levels. Oral administration of Con A (either 250 μg or 500 μg/mouse) or purified PG (1 mg/mouse) at the time of TNp‐S. mutans immunization resulted in significantly (P≤ 0.01) enhanced splenic IgA anti‐TNP PFC responses, especially in C3H/HeJ mice. On the other hand, MDP promoted IgA anti‐TNP PFC responses in LPS‐responsive C3H/HeN mice but did not augment responses in C3H/HeJ animals. A similar immune response pattern was seen when antibody levels were measured in serum, saliva, and urine of both mouse strains. These results demonstrate that haptenated S. mutans is a good antigen for the induction of high IgA responses in orally immunized C3H/HeJ mice and that this high response can be enhanced with the adjuvants Con A and PG. However, MDP is ineffective in C3H/HeJ mice but enhances IgA responses in normal LPS‐responsive C3H/HeN animals.
Antigen‐Trapping Cells in Peyer's Patches of the Rat
Authors: SMINIA T. , JANSE E. M. , WILDERS M. M.
Published: June 2006

Peyer's patches (PP) of rats were studied with immunocytochemical, enzyme cytochemical, and electron microscopic techniques. Special attention was paid to the non‐lymphoid antigen‐trapping cells. Follicular dendritic cells, morphologically comparable to those present in spleen and lymph nodes, were found in the germinal centers of PP. la‐positive cells with the morphological characteristics of interdigitating cells were seen in the interfollicular area. Thus, both types of antigen‐presenting cells, characteristic for B‐ and T‐cell areas, respectively, were present in PP.
Cleavage of the Four Human IgG Subclasses with Cathepsin G
Authors: BAICI A. , KNÖPFEL M. , FEHR K.
Published: June 2006

Cathepsin G, the chymotrypsin‐like serine proteinase from human polymorphonuclear leucocytes, cleaves human IgG. The relative susceptibilities of the four IgG subclasses to the action of this enzyme were studied kinetically and showed the following decreasing order of susceptibility: IgG3≫ IgG4>IgG1>IgG2. IgG1 and IgG2 produced primarily F(ab′)s and traces of Fc‐related fragments. IgG4 gave rise to both Fab and F(ab′)2 as major products, and small amounts of an Fc‐related fragment were detected. The cleavage of IgG3 produced various fragments, depending on the experimental conditions: The primary fragments were Fab and Fch (Fc covalently joined to the extended hinge‐region polypeptide of IgG3) and an intermediate Fab‐Fch species. Both Fab and Fch were further degraded by cathepsin G. Fch was gradually split, giving rise to three subfragments that were finally degraded to dialysable peptides. The enzyme further cleaved the Fab fragment in the heavy‐chain portion and released a polypeptide probably representing the VH domain.
Expanded Progeny Cells of Diffuse Cytotoxic Bone Marrow‐Derived Colonies
Authors: CLAËSSON M. H. , MARTINSEN L. , GOUTNER A. , OLSSON L. , BRTX‐POULSEN P.
Published: June 2006

Bone marrow‐dervied (colony‐stimulating factor [CSF]‐dependent) diffuse colonies have been shown to include colonies with cytotoxic activity. Such diffuse colonies were expanded for 6–8 weeks in liquid culture medium in the presence of pokeweed mitogen‐ or concanavalin A‐conditioned spleen cell medium (CM). The morphology of the expanded diffuse colony cells (EDCC) was like that of early myelocytic cells. EDCC lost their cytotoxic capacity when expanded, but the cytotoxicty could be reinduced by pretreatment of the colonies with interferon or phorbol ester. Traditional sources of mouse or human CSF such as lung CM, placenta CM and human mononuclear cell CM did not support proliferation of EDCC, whereas partly purified interleukin‐3 (IL‐3), lacking CSF and IL‐2, was stimulatory for EDCC. Thus, the stimulatory factor for EDCC was not CSF but a factor closely related to IL‐3. Monoclonal antibodies against T lymphocytes or macrophages did not bind to EDCC. EDCC did not have Fc receptors, but 10% of the cells were positve for a monoclonal anti‐la antibody. All EDCC were positive for αNAE and NASDCI esterases but negative for acid and alkaline phosphatases and peroxidase reactivity; less than 2% of the cells showed metachromatic staining with toluidine. Ultrastructurally, EDCC showed various degrees of cell differentiation but absence of specific cytoplasmatic characteristics such as neutrophilic, eosmophilic, basophilic and mast cell granules. Current work aims to define factors and conditions necessary for the induction of differentiation in these immature monomyelocytic cells.
Monoclonal Antibodies against Human Monocytes
Authors: NUNEZ G. , UGOLINI V. , CAPRA J. D. , STASTNY P.
Published: June 2006

Three monoclonal antibodies (63D3, 63D2, and 61D3) with reactivity against human monocytes have been studied. They reacted with most adherent mononuclear cells but not with pure populations of peripheral blood B and T lymphocytes. Two of these antibodies, 63D3 and 63D2, competed in fluorescence inhibition experiments, recognized a monocyte surface antigem of about 200,000 daltons, and werre idiotypically related. The third antibody, 61D3, did not compete with the others in fluorescence inhibition experiments, recognized a different surface molecule, and was idiotypically distinct from 63D3 and 63D2. Whereas 63D3 and 63D2 reacted very weakly with some granulucytes, 61D3 did not, suggesting that it is specific for monocytes alone.
Measurement of IgE on Rat Mast Cells: Relation to Serum IgE and Allergen‐Induced Histamine Release
Authors: VAN TOORENENBERGEN A.W. , VAN SWIETEN P. , AALBERSE R. C.
Published: June 2006

IgE antibodies against trinitrophenylated ovalbumin (TNP‐OVA) were raised in Brown Norway rats by a highly reproducible immunization procedure. With these rats, the kinetics of the IgE response was studied, both for free circulating and cell‐bound IgE. Cell‐bound IgE was dissociated from peritoneal cell suspensions at acid pH; TNP‐specific and total IgE in serum and in eluates of peritoneal cells were determined by radioimmunoassay. Both for total and TNP‐specific IgE, a significant correlation was found between the serum IgE level and the amount of IgE molecules per mast cell. One day before TNP hapten could induce histamine release from mast cells, TNP‐specific IgE appeared in the circulation and on the cells. These results suggest that also in active sensitization, there is a lag time for sensitization of mast cells.
Identification of Three Major Synovial Lining Cell Populations by Monoclonal Antibodies Directed to Ia Antigens and Antigens Associated with Monocytes/Macrophages and Fibroblasts
Authors: BURMESTER G. R. , DIMITRIU‐BONA A. , WATERS S. J. , WINCHESTER R. J.
Published: June 2006

Synovial lining cells obtained from patients with rheumatoid arthritis or noninflammatory joint diseases were divisible into three populations according to the expression of surface antigens detected by various monoclonal antibodies. A population of cells designated type I was defined by the presence of Ia antigens, Fc receptors, five different monocyte lineage differentiation antigens, and the property of phagocytosis. The greatly increased amounts of both Ia antigens and certain monocyte lineage antigens distinguished these cells from blood monocytes. A second distinctive cell population was non‐phagocytic, occasionally binucleate, and had abundant Ia antigens but lacked IgG Fc receptors, monocyte lineage antigens. B or T lymphocyte antigens, and fibroblast‐associated antigens detected by reagents raised against synovial cells. This population, designated type II, accounted for approximately one‐third of the synovial cells in patients with rheumatoid arthritis but few or no cells in the synovial lining of patients with non‐inflammatory diseases. The Ia‐positive synovial cells with a dendritic morphology were contained in this population. An additional population, designated type III, contained nearly all of the remaining cells and was defined by the presence of antigens expressed primarily on fibroblasts and by the absence of phagocytosis, demonstrable Ia antigens, and four antigens of the monocyte lineage. This population exhibited proliferative capacity, becoming the predominant cell in long‐term cultures. The proportions of each population varied considerably from patient to patient.
Age‐Dependence of the IgA Anti‐α(1→3) Dextran B1355 Response in Vitro
Authors: RIVIER D. A. , TREFTS P. E. , KAGNOFF M. F.
Published: June 2006

The magnitude of the Balb/c mouse IgA anti‐α(1→3) dextran B1355 (anti‐dex) response in vivo was recently found to be markedly T‐cell‐dependent and age‐dependent. This report demonstrates that the in vitro IgA anti‐dex response by mesenteric lymph nodes (MLN) is highly age‐dependent and that there is an age‐dependent increase of the background IgA anti‐dex plaque‐forming cell (PFC) response occurring in the absence of added antigen which correlates significantly with the magnitude of the antigen‐stimulated response. In aging mice both background and antigen‐stimulated IgA anti‐dex responses appeared to be significantly higher in MLN than in spleen cultures. Moreover, it is shown that there is a striking increase with age of natural antibody in the serum of normal Balb/c to α(1→3) film‐in determinants, particularly IgA and lesser amounts of IgM and IgG3.
Quantitation and Estimation of Cooperation between Target‐Binding Sites in Natural and Antibody‐Dependent Cell‐Mediated Cytotoxicity by Use of a Mathematical Transformation
Authors: KREBS H. J. , NORRILD B.
Published: June 2006

We have studied the use of a mathematical transformation, the Hill transformation, in natural and antibody‐dependent cell‐mediated cytotoxicity as a function of effector cell concentration. It can be concluded that when adherent cells are removed from the effector cell suspension, cooperation between binding sites for effector cells on the target cell changes from negative to zero. After stimulation of nonadherent cells with α‐interferon, the binding sites still remain noninteracting. This is the case both in natural and in antibody‐dependent cell‐mediated cytotoxicity experiments. The Hill transformation seems to be an easy and easily reproducible way of quantitating cytotoxicity.
Sendai‐Virus‐Induced Cell‐Mediated Cytotoxicity in Vitro
Authors: ALSHEIKHLY A. , ÖRVELL C. , HÄRFAST B. , ANDERSSON T. , PERLMANN P. , NORRBY E.
Published: June 2006

Treatment of peripheral blood lymphocytes from normal donors with small amounts of purified Sendai virions results in enhanced cellular cytotoxicity in vitro to uninfected tissue culture target cells (virus‐dependent cellular cytotoxicity (VDCC)), without any obvious correlation to the natural cytotoxicity (NK) displayed by the lymphocytes in the absence of virus. Removal from the virions of the two surface components present in the viral envelope, the HN glycoprotein (gp 71), carrying haemagglutinating and neuraminidase activity, and the F glycoprotein (gp 49), carrying fusion activity, by treatment with pronasc abrogated their capacity to induce VDCC. Similar results were obtained when virions lacking the HN glycoprotein after treatment with chymotrypsin were added to the lymphocytes. In contrast, treatment of the virus particles with trypsin, which removed the F glycoprotein, did not affect their capacity to induce VDCC. When the solubilized and separated peplomers were used for lymphocyte treatment, either alone or in combination, the purified HN glycoprotein had full capacity to induce VDCC, whereas the F glycoprotein was inactive. These results suggest that the HM peplomer is solely or primarily responsible for the cytolytic activity arising in non‐sensitized lymphocytes when confronted with certain viruses.
Different Responses Elicited in Vitro by Antibodies to IgM and IgD in Cells from a Surface IgM + D‐Positive Human Follicular Lymphoma
Authors: RUUD E. , STEEN H. B. , BEISKE K. , GODAL T.
Published: June 2006

The effect of anti‐Igs in combination with the tumour promoter TPA on DNA and Ig synthesis in a human follicular germinal centre cell lymphoma carrying slgM and slgD was investigated. The lymphoma cells responded to both amiti‐μ and anti‐γ chains and to anti‐δ light chains by DNA synthesis, as measured by mcthy‐(3H)‐thymidine incorporation. Flow cytofluorometric measurements, however, showed that only anti‐μ chains induced marked increase in cytoplasmic Ig content. This result suggests that in certain B‐cell subsets the signals elicited via slgM and slgD are different.
A VH‐Associated Idiotype in Human Anti‐Tetanus Antibodies
Authors: ALTEVOGT P. , WIGZELL H.
Published: June 2006

An anti‐idiotypic (α Id) serum was induced against anti‐tetanus toxoid (α TET)‐reactivc F(ab')2 fragments of a single donor. After appropriate adsorption the serum was shown to react only with α TET F(ab')2 fragments and not with F(ab')2 fragments deplcted of α TET reactivity or anti‐diphtheria toxoid (DIP) or anti‐purified protein derivative (α PPD) F(ab')2 fragments of this donor. Inhibition studies with soluble TET indicated that the anti‐idiotypic serum partly reacts with determinants close to or within the antigcnic binding site. When tested on a small panel of α TET F(ab')2 fragments derived from unrelated donors, one out of four donors tested showed cross‐reactivity. When tested on α TET F(ab')2 fragments derived from related family members, the donor's father and two sisters were found to cross‐react, whereas the mother and two other sisters did not. The observed cross‐reactivity was independent of the litres of α TET antibodies in the serum. Furthermore, two‐dimensional gel electrophoretic studies carried oui on α TET IgG of Id‐positive or Id‐negative family members indicated that the expression of idiotypic determinants is linked to a particular heavy chain. Immunofluorescent staining with α Id and cytofluoro‐graphic analysis of donor T‐lymphoblast proliferation in response to TET showed that the T cells did not express Id determinants found on his α TET antibodies.
Effect of Interferon on Cell Proliferation and Generation of Cytotoxic Potential in Mixed Autologous and Allogeneic Lymphocyte Cultures
Authors: ARGOV S. , KLEIN E.
Published: June 2006

Autologous and allogeneic mixed lymphocyte cultures (AMC and MLC) were assayed for blastogenesis, generation of cytotoxic potential, and the effect of interferon (IFN‐α) on these features. The cells of the mixed cultures lysed K562. Daudi, and autologous and allogeneic phytohaemagglutinin blasts. Stimulator‐specific cytotoxicity was observed only in MLC. B blasts induced with Staphylococcus aureus were only affected in a stimulator‐specific manner. Short‐term IFN treatment of the MLC‐derived effectors before the lytic assay enhanced the nonspecific component of cytotoxicity. Cell proliferation was considerably lower in AMC than in MLC. This was decreased when IFN‐α was added at the initiation of the cultures. The presence of IFN influenced the generation of lytic potential. Comparison of the lysis of the different targets exerted by MLC‐activated cells suggested that the specific component was more substantially elevated than the nonspecific one. It is likely that the IFN induced such modifications in the culture conditions that favoured the proliferation of the specific clone. Re‐exposure of lymphocytes cultured in the presence of IFN to another dose of IFN before the assay had no influence on their lytic potential.
In Vitro Effects of Cyclosporin A on Human B‐Cell Responses
Authors: BERGER R. , MEINGASSNER J. G. , KNAPP W.
Published: June 2006

The in vitro effects of cyclosporin A (CsA) on T‐cell‐dependent and T‐cell‐independent mitogen responses of human B cells were studied. T‐cell‐dependent, pokeweed mitogen (PWM)‐induced B‐cell proliferation and B‐cell differentiation to Ig‐secreting cells were significantly inhibited by CsA, when purified B cells were cultured with T‐cell helper factor containing supernatants instead of T cells. This indicates that the inhibitory effect of CsA on T‐cell‐dependent, PWM‐induced B‐cell proliferation and differentiation is not exclusively due to direct effects on helper T cells. B‐cell proliferations induced by anti‐IgM antibodies and by Staphylococcus aureus bacteria were also found to be sensitive to CsA. Since both types of reactions are T‐cell‐independent, the concept that responses of human B cells can also be affected by CsA in ways that seem to be independent of the well‐documented direct effects of CsA on T cells is further supported. This seems not to be a general phenomenon, however. Epstein‐Barr‐virus‐induced activation of human B cells, as reported previously and also observed by us, is completely insensitive to CsA. It seems, therefore, that certain B‐cell activation mechanisms are sensitive to CsA while others remain unaltered. The difference between these two reaction patterns cannot be exclusively explained by a T‐cell dependence or T‐cell independence of these responses. CsA effects on certain functional B‐cell subsets or interference with accessory cell mechanisms might be responsible.
Identification of Allergens in Dermatophagoides pteronyssinus Mite Body Extract by Crossed Radioimmunoelectrophoresis with Two Different Rabbit Antibody Pools
Authors: LIND P. , LØWENSTEIN H.
Published: June 2006

An extract of purified Dermatophagoides pteronyssinus mite bodies was investigated by crossed radioimmunoelectrophoresis (CRIE), using sera from 29 mite‐allergic patterns. Two CRIE series consisting of rabbit antibodies to (1) whole mite culture and to (2) purified mite bodies were run simultaneously, showing 27 and 29 precipitates, respectively. Cases of major discrepancy between the two series were ascribed to absence of antibody 10 allergenic components and to artefactual radiostaining due to inclusion of allergen in precipitates representing other antigens. Carefully performed controls were necessary to establish the reliability of CRIE. Specific response patterns in the studied set of sera were found to several of the represented antigens. Two major allergens appeared in both CRIE systems. Two intermediate and several minor allergens were further identified.
Solid‐Phase Synthesis of the Non‐Calcium‐Binding Loop of Cod Allergen M
Authors: ELSAYED S. , RAGNARSSON U. , NETTELAND B.
Published: June 2006

The synthesis of the non‐calcium‐binding AB loop of the assembly 13–32 of cod Allergen M (M r 2122.1) was accomplished by solid‐phase peptide synthesis. This peptide and the previously synthesized ones [12, 13, 14] have significant amino acid sequence homology. The synthetic crude preparation was obtained at relatively high recovery and purity. Further purification on a Bio‐Gel P‐2 column and a reversed‐phase high‐performance liquid chromatography column improved the grade of homogeneity, as demonstrated by high‐voltage electrophoresis, end‐terminal analysis, and amino acid composition. The peptide could, although to a much weaker extent than the intact Allergen M, directly bind IgE antibodies from the sera of cod‐allergic individuals. At identical molar concentrations, a ratio of 1:6 for the in vitro reactivity of the peptide relative to the intact Allergen M was obtained. A similar reactivity was shown in the in vivo system used. The peptide also reacted with rabbit anti‐Allergen M antibodies in rocket immunoelectrophoresis. The peptide appears to function as a divalent molecule in its primary interaction with antibodies.
Induction of Human T Colony Formation by Phorbol Myristate Acetate
Authors: KLEIN B. , REY A. , JOURDAN M. , DONNADIEU M. H. , SERROU B.
Published: June 2006

Phorbol myristate acetate (PMA) is a potent inducer of T colony formation by peripheral blood lymphocytes. A mean cloning efficiency of 0.3% (0.05‐0.5%) is obtained with PMA concentrations of 100‐1000 ng/ml. PMA‐induced T colony formation does not require the presence of monocytes and therefore differs from other mitogens in this respect. Purified T‐colony‐promoting activity (TCPA) (devoid of phytohaemagglutinin (PHA)) increases PMA‐induced T colony numbers and induces T colony formation at low PMA doses (0.01 to 1 ng), concentrations at which no T colonies are detected in the absence of added TCPA. PMA‐induced colonies are mainly composed of cells bearing Fc receptors for IgM (54%), which is not the case for colonies obtained with PHA (11 %). PMA‐induced colony cells do not bind OKT3 and OKT4 monoclonal antibodies, whereas 23% are able to bind OK‐T8 antibody. These results demonstrate that PMA is a potent inducer of T colony formation and may therefore serve as a useful tool for the study of T‐cell differentiation.
Selective Functional Role of Murine TM and TG Cells in Concanavalin‐A‐Induced T‐Cell Activation
Authors: SKOGLUND A.‐C. , LARSSON E.‐L. , ANDERSSON B.
Published: June 2006

Murine splenic cells were separated on Ig‐anti‐Ig columns to yield cell populations depleted of IgM‐FcR (Fc receptor)‐expressing (Tm−) and IgG‐FcR‐expressing (Tg−) cells and also cells expressing neither of these two FcR (To). The proliferative response to the lectin concanavalin A (Con A) was shown to be present mainly in cell populations depleted of Tm cells (T cells lacking IgM FcR)—that is. Tm− and To. The low Con A response in the other cell populations, namely Tg− and Ttot, was due to a selection against T‐cell growth factor (TCGF)‐reactive cells, since TCGF production within these subsets was not impaired and the low proliferative response was not reconstituted by preformed TCGF. Tg− cells were able to inhibit the Con‐A‐induced proliferation of To and Tm− cells dose‐dependently. These data strongly suggest the presence of a step‐one regulatory, suppressive mechanism comprised within the Tm population.
Differences in Binding Sites for Prostaglandin E2 on Mononuclear Leucocytes from Human Newborns and from Their Mothers
Authors: JOHNSEN S.‐Aa. , OLDING L. B.
Published: June 2006

Binding of [3H]prostaglandin E2 (PGE2) to peripheral mononuclcar leucocytes (PML) from newborns and their mothers was studied. Specific binding of PGE2 to both maternal and neonatal PML was found. The binding was maximal after 15 min of incubation at 37°C and specific for PGE1 and PGE2 versus PGA1, PGF1aL, and PGF2α. The amount of PGE2 specifically bound to neonatal PML was about 30% of the amount bound to maternal PML. The average number of binding sites for PGE2 on maternal PML was calculated to 1800 per cell, and the dissociation constant (KD) was 6.5 × 10−9m. The corresponding figures for neonatal PML could not be calculated owing to the low number of binding sites on those cells. After preincubation for 18 h the binding of PGE2 to maternal PML was decreased and equalled that of PGE2 to neonatal PML, whereas neonatal PML were unaffected by preincubation. These results indicate that differences in sensitivity to suppression by PGE and the effect of preincubation may be linked to differences in binding of PGE.