bluuebunny/crossref_metadata_2025 huggingface dataset:
The IgA‐Binding Lectin Jacalin Induces Complement Activation by Inhibition of ‐Inactivator Function
Authors: HIEMSTRA P. S. , GORTER A. , STUURMAN M. E. , VAN ES L. A. , DAHA M. R.
Published: June 2006

Jacalin. a D‐galaetose‐specific lectin from jackfruit, interacts with human IgA and one or two other serum proteins. Incubation ol jaealin with fresh human serum was shown to result in activation of the complement system. Therefore the mechanism of complement activation by jacalin was studied. Jacalin was extracted from jackfruit seeds (crude preparation) and purified to homogeneity by affinity chromatogtaphy on lgA‐Sepharose to yield a pure preparation of jacatin. Both crude and pure Jacalin were able to activate complement, accompanied by conversion of C3. Consumption of C1, C4 and C1 ‐inacuvator(Cl ‐In) indicated involvement of the classical pathway. Aggregated IgG (AlgGl caused partial (38%) and jacalin induced complete consumption of Cl ‐ln functional activity, It was found upon Ouchterlony analysis that jacalin forms a precipitalien line with purified Cl ‐In. In addition binding of 125I‐C1 ‐In to jacalin‐Scpharose was observed, and this binding was inhibitable by either secretory IgA or D‐galactose. Next to binding of jacalin to Cl ‐In. jacalin was also shown to inhibit the functional activity of Cl ‐In. These results indicate that jacalin induces complement activation by inhibition of Cl ‐In function and thereby facilitates the activation of precursor Cl in either the absence or presence of low amounts of Cl aetivators.
Autologous Red Blood Cells Potentiate Antibody Synthesis by Unfractionated Human Mononuclear Cell Cultures
Authors: RUGELES M. T. , VIA M. LA , GOUST J.‐M. , KILPATRICK J. M. , HYMAN B. , VIRELLA G.
Published: June 2006

We have tried to determine the most favourable conditions for the in vitro induction of specific antibody (Ab) responses to tetanus toxoid (TT) and keyhole limpet haemocyanin (KLH). Human peripheral blood mononuclear eells (PBMNC) were obtained from normal volunteers and stimulated with PWM, TT, KLH. and mixtures of PWM and antigens in the presence or absence of autologous red blood cells (RBC) (I:50 ratio of PBMNC/RBC). The cultures were harvested on day 11: immunogiobulins were determined immunonephelometrically and Ab levels by ELISA with human antibodies used for calibration. While anti‐TT responses were easy to induce with PBMNC from recently boosted individuals, the production of anti‐IT from PBMNC obtained from non‐recently boosted individuals was only possible when PBMNC were stimulated with TT and PWM in ihe presence of autologous RBC Similarly, anti‐KLH responses were easier lo induce with PBMNC frt)m an immune donor; maximal response was observed after slimuiation wiih PWM + KLH in the presence of autologous RBC. Stimulation of primary anti‐KLH responses with PBMNC from non‐immune donors was only successful when the cells were stimulated with KLH + PWM in the presence of autologous RBC. The potentiation of human B‐cell responses with autologous RBC can be abrogated by pretreatment of PBMNC with anti‐CD2 antibodies and is associated with increased expression of IL‐2 receptors and increased production of gamma interferon (IFN‐γ). However, addition of IFN‐γ in different doses and at different times to PWM‐slimulaled PBMNC cultures was not as effective as addition of RBC in enhancing the production of immunoglobulin and antibody.
Implantation of Cultured Thymic Fragments in Congenitally Athymic (Nude) Rats Influx of Lymphocytes and Dendritic Cells
Authors: SCHUURMAN H.‐J. , VAESSEN L. M. B. , BROEKHUIZEN R. , BRANDT C. J. W. M. , HOLEWIJN M. C. , VOS J. G. , ROZING J.
Published: June 2006

We studied the early events in athymic immunoincompetent rats after implantation with cultured thymic fragments (CIF) under the kidney capsule, with special emphasis on the settlement of lymphocytes and non‐lymphnid RTl class II elements. At 2 weeks after grafting, tissue under the kidney capsule comprises strands of keratin‐positive epithelial cells from the graft, without immigrant cells. At 3 weeks, the CTF graft is populated with lymphoeytes and with non‐lymphoid RTl class II‐positive cells expressing the recipient haplotype (allogeneic combinations). Part of these cells bear determinants recognized by an anti‐rat dendritic cell antibody. At 4 weeks the graft exhibits a completely restored thymic architecture. Al the periphery, the first indications of T‐cell competence generated after CTF implantation are observed 6 weeks after implantation. At 18 weeks. the peripheral thymus‐dependent immune system is almost completely developed. This includes in vitro alloreactivity, even to the donor RTl haplotype of the graft. But skin grafts of the allogeneic CTF donor haplotype are not rejected. Thus, a state of in vivo tolerance is induced under the influence of grafted epithelium, which is not due to a specific deletion of alloreactive cells. We conclude that CTF regain their original thymic architecture between 2 and 4 weeks after implantation in (allogeneic) athymic nude recipients, and that only after this restoration does peripheral thymus‐dependent immune competence start to develop.
The Localization of Antigen in Lymph Node Follicles of Congenitally Athymic Nude Rats
Authors: MJAALAND S. , FOSSUM S.
Published: June 2006

We have examined the postulated dependence on T cells of follicular retention ot antigen bystudying antigen retention in the draining lymph nodes of congenitally athymic. nude rats afterlocal injections of horseradish peroxidase (HRP). The lymphoid tissues of these rats containedgerminal centres and follicular dendritic cells (FDC) that were ulrastructurally identical tothose seen in euthymic rats and expressed the differention antigen MRCOX2. Nude rat FDCcaptured and retained locally injected antigen on their surfaces. but as with euthymic rats, onlyin the presence of previously injecled anti‐HRP antibody. This demonstrates that the FDCmature both morphologically and functionally in the absence of a thymus or T cells. However, in contrast to euthymic rats, there was no detectable antigen retention in nude rats that hadbeen actively immunized by repeated intraperitoneal injections with HRP for 3 months. Thelower number of germinal centres observed in athymic animals compared with their euthymiclittermales could thus be explained by deficient production of specific antibody of the isotypenecessary for follicular localization of environmental antigens.
Immunopurification of Radiolabelled Antigens of Mycobacterium leprae and Mycobacterium bovis (Bacillus Calmette‐Guerin) with Monoclonal Antibodies
Authors: BRITTON W. J. , HELLQVIST L. , IVANYI J. , BASTEN A.
Published: June 2006

Radiolabelled sonicate of Mycobacterium leprae when examined by SDS‐PAGE and two‐dimensional gel electrophoresis (2‐DE) contained fewer antigens than the comparable sonicate from M. Bovis (bacillus Calmette‐Guerin) (BCG). A solid‐phase immimopurification assay with anti‐M. lrprae monoclonal antibodies (MoAb) was used to characterize four of these antigens. Three of the MoAb were M. leprae‐specific and with them antigens with apparent molecular weights (M1) of 12,000 (I2K), 18K. and 35K were isolated. On 2‐DE, the heavily labelled I2K antigen was heterogeneous with a range in pI of 4.8‐5.2. The 35K antigen, which was identified by a conformational determinant, and the 18K antigen were also acidic proteins with pI of 5.4 and 5.1. The fourth antigen was purified from both M. leprae and BCG sonicates and had an M, of 70K and a pI of 5.1. MoAb reacting with the cell wall protein of M. leprae resulted in separation of multiple bands ranging in M1 from 12K to 65K, rather than the dominant 65K protein seen in immunoblots. A similar pattern was obtained with MoAb that reacted with two cell wall polysaccharide antigens, and these antibodies may have co‐prceipitated the radiolabelled cell wall proteins. Immunoprecipitatcs of the M. leprae sonicate with human lepromatous leprosy sera, when analysed by 2‐DE, were also found to contain the dominant 12K band and the 35K band. Furthermore, half the radiolabelled BCG antigens were precipitated by ihc same sera.
In Vitro and in Vivo Stimulation of Murine Lymphocytes by Human Respiratory Syncytial Virus Strains
Authors: ALSHEIKHLY A. R. , NORRBY E.
Published: June 2006

Respiratory syncytial virus (RSV) strains of subtype A (A2, WV99894, and WV12138) and of subtype B(WV1293. WV4843. and WV6873) are mitogenic in vitro for unprimed BALB/c spleen cells. The virus also triggered splcnocytes in vitro to secrete immunoglobulins. Plaquepurified and UV‐irradiated materials of both RSV subtypes produced comparable levels of DNA synthesis. Infectious materials of both subtypes also induced pronounced responses. Lymphocyte activation with UV‐inactivated RSV strain A2 was dose‐dependent and maximal responses occurred after 4‐5 days of incubation. The virus preparations were mitogenic for spleen cells depleted of T lymphocytes by treatment with anti‐Thy 1.2 and complement and for lymphocytes of congenilally athymic mice (nu‐nu). They were also mitogenic for highly purified T lymphocytes separated by panning of spleen cells on anti‐mouse Ig‐coalcd Petri dishes, suggesting that both B and T lymphocytes respond to the mitogenic activity of RSV. Moreover, mice infected intranasally with RSV strain A; generated local as well as peripheral cellular and humoral responses.
Monocyte‐Derived Influence on Growth of Normal Human Fibroblasts
Authors: AUSTGULEN R. , NISSEN‐MEYER J. , DEGRE M. , ESPEVIK T.
Published: June 2006

The current study demonstrates that whereas high concentrations of recombinant tumour necrosis factor (rTNF. 0.05/(g/ml) induced enhanced growth of normal human fibroblasts, supernatants from human monoeytes with u similar TNF concentration induced cytostasis. This cytoslasis was inhibited by an antiserum against rTNF. The TNF activity, measured as cytotoxicity against TNF‐sensitive WEHI 164 cells, cochromatographed with the fibroblast growth inhibitory activity upon ion‐exchange chromatography of monocyte supernatants. This indicates that TNF contributes to the fibroblast growth inhibition mediated by monocyte supernatants. Alpha inierfcron (IFN‐α) abolished the growth of fibroblasts induced by rTNF, whereas rTNF in combination with gamma interferon (IFN‐α) inhibited growth of fibroblasts. The interferon activity in the supernatants was determined to find out whether the growth inhibitory activity of natural TNF was due to interferons present in the monocyte supernatants. which might modulate the TNF activity. Cytostasis of fibroblasts was mediated by monocyte supernatants which did not contain IFN‐γ in significant amounts. All supernatants contained IFN‐α. An antiserum against lFN‐α partially reduced the cytostasis induced by monocyte supernatants. This cylostasis was totally abolished by r TNF antiserum, suggesting that IFN‐α modulates the growth‐inhibitory activity of TNF in the monocyte supernatants It appeared that the different effects of recombinant and natural TNF on fibroblast growth can probably not be attributed to monocyte‐derived TNF‐modulating factors alone. Thus, recombitiant and natural TNF may differ in a way that affects their capacity to induce cytostasis of normal fibroblasts.
Effects of Ethanol on Human Monocyte IgG Fc Receptors
Authors: MØRLAND B. , MØRLAND J.
Published: June 2006

The IgG Fc receptor function of human monocytes (Mo) exposed to ethanol in vitro was assessed by a rosette assay in which IgG‐coated sheep red blood cells were used as test particles. Pre‐incubation of Mo in autologous serum with ethanol (55 mM and above) for 15 min at 37°C, caused a significantly lower percentage of Mo‐forming rosettes. This reduction by ethanol was not observed when Mo were preincubated with ethanol in fetal calf serum or in serum‐free conditions, but was present when Mo were pre‐incubated with ethanol in serum‐free media to which IgG (10‐150 μg/ml) had been added. Donor‐dependent differences were observed in the reduction of Mo‐forming rosettes in the presence of autologous serum and ethanol. Mo allowed to form rosettes without ethanol were exposed to ethanol during a subsequent phagocytosis process. A dose‐dependent inhibition of the internalization of test particles was found in Mo from all donors.
Circulating Cholera Antitoxin Memory Cells in the Blood One Year after Oral Cholera Vaccination in Humans
Authors: LYCKE N. , HELLSTRÖM U. , HOLMGREN J.
Published: June 2006

Oral vaccination with the combined B subunit/whole cell cholera vaccine generates antitoxin memory cells that could be isolated from peripheral blood for at least 1 year after immunization. These memory cells were triggered by antigen in vitro to produce antitoxin in the presence of autologous T cells and monocytes. Antitoxin‐producing peripheral blood lymphotes (PBL) were found in 4 out of 5 previously vaccinated subjects. IgA and IgM isotypes dominated the momery response. The antigen‐dose dependency and requirement for a specific ratio of T to B cells for activation of the memory cells in vitro implies T‐cell control of antitoxin responses. These antitoxin memory cells in peripheral blood (and corresponding antibacterial memory cells) might represent it pool of circulating cells that on renewed exposure to cholera rapidly produce protective antibody in the gut and thus might have a central role in the long‐term protection against reinfection and disease seen in convalescents from cholera.
Human IgD and IgAl Compete for D‐Galactose‐Related Binding Sites on the Lectin Jacalin
Authors: ZEHR B. D. , LITWIN S. D.
Published: June 2006

Lectin selectivity for human ig classes is based on carbohydrate differences. Earlier reports that the lectin jacalin precipitated human igA were confirmed and supplemented by the current study, which demonstrates that jacalin also binds human IgD as evaluated by micro‐ELlSA and SDS‐PAGE. Experimental findings indicated that: (i) Monoclonal and polyclonal (sera) IgD. IgAl, bul not IgA2, IgM, or IgGI‐4 reacted with jacalin, (ii) Six tested monoclonal IgD proteins each bound approximately equally to jacalin when antigenicity rather than protein concentration was measured; the results weigh against the presence of jacalin‐delectable IgD subclasses or genetic variants, (iii) IgD and IgAl both associated maximally in 4‐8h at 4°C. There was no dissociation at 4°C but limited dissociation occurred at 37°C after 24h, (iv) Both IgD and IgAl were eluted from jacalin by galaetose‐related sugars, (v) IgD and IgAI bind competitively to jacalin. The results suggested that jacalin reacts with O‐linkcd oligosaccharide N‐acetyl‐galactosamine (GalN) residues found on the hinge region of both IgD and IgAl, Jacatin also interacted with one major and several minor unidentified sera proteins. The findings offer an approach to the isolation of serum polyclonal IgD and to the characterization of the unusual carbohydrates of the human delta heavy chain with respect to their function.
The Immunodeficiency of Bone Marrow‐Transplanted Patients
Authors: ØDUM N. , HOFMANN B. , JACOBSEN N. , LANGHOFF E. , MØLLER J. , PLATZ P. , RYDER L. P. , SVEJGAARD A.
Published: June 2006

Lymphocytes from 21 patients sampled 1‐6 months after bone marrow transplantation (BMT) were tested for functional suppressor activity against marrow‐donor lymphocytes in the lymphocyte transformation test. Suppression of donor responses to allogeneic (i.e. mixed lymphocyte reaction, MLR) and antigenic stimulation by irradiated (7600 rad) post‐BMT cells was observed in about two‐thirds of the combinations tested (N=20 and N=9). The suppression of donor MLR and antigen responses ranged between 5‐52% and 10‐46%, respectively. Irradiated post‐BMT cells significantly suppressed donor responses to suboptimal concentrations of phytohaemagglutinin (PHA) (median suppression: 28%; P<0.05; N=7) and concanavalin A (Con A) (median suppression: 31%; P<0.05; N=6). A clearly suppressive effect of post‐BMT cells was observed when the ratios of CD4+/CD8+ post‐BMT cells were lower than 0.5 (P<0.01). In three experiments, the depletion of the CD8‐ but not of the CD4‐positive subset abrogated the suppression of the donor MLR by post‐BMT cells. The suppression by post‐BMT cells (irradiated) of MLR and mitogen responses was comparable whether the responding cells were derived from the donor or from HLA‐DR‐incompatible, unrelated individuals. The proliferative capacity of post‐BMT cells compared to that of donor cells was assayed in the MLR with unrelated, HLA‐DR‐incompatible stimulator cells. A significantly decreased proliferative capacity (median 20% of that of donor cells) was found (P<0.01; N=16). A weak inverse correlation (P<0.05; N=16) between the proliferative and the suppressive capacity of post‐BMT cells in the MLR was observed. These findings indicate that the decreased proliferative capacity upon mitogen, antigen, and alloantigen stimulation observed in most patients within 1‐6 months after BMT may be partly due to non‐specific suppression by CD8+ cells.
Effects of Monoclonal Anti‐T Cell Antibodies on Rat Cardiac Allografts
Authors: CLAESSON K. , KLARESKOG L. , LARSSON P. , HOLMDAHL R. , FORSUM U. , SCHEYNIUS A. , TUFVESON G.
Published: June 2006

Monoclonal antibodies reactive with different T lymphocyte antigens were administered to rats receiving heart allografts. Ox 19 antibodies (directed to the rat Ly 1 equivalent) and Ox 8 antibodies (directed to the rat CD8 equivalent) both prolonged graft survival, whereas W3/25 (anti‐CD4). Ox 6 (anti‐Ia), and W3/13 (anti‐pan T) antibodies did not affect graft rejection. Immunohistological studies were carried out on spleen and graft specimens in order to analyse further the mechanisms behind the prolongation of graft survival. The observed almost complete absence of Ox 8‐reactive cells in the spleen after treatment with Ox 8 antibodies corroborates earlier observations that injection of moderate amounts of Ox 8 antibodies leads to complete elimination of suppressor/cytotoxic T cells from peripheral lymphoid organs and blood. The present data on graft survival therefore both support the notion that suppressor/cytotoxic T cells are involved in graft rejection, and suggest that these cells are not the only ones involved. An unexpected and as yet unexplained finding was that Ox 8‐reactive molecules were found in large numbers on various inflammatory cells as well as on certain myocytes in the grafted hearts that had experimenced a prolonged graft survival due to treatment with Ox 8 or Ox 19 antibodies.
Recognition of Rat Dendritic Cells by a Monoclonal Antibody
Authors: NAGELKERKEN L. M. , SCHUTTE B. , STET R. J. M. , VAN BREDA VRIESMAN P. J. C.
Published: June 2006

A mouse monoclonal IgM antibody reactive with dendritic cells (DC) from the Brown Norway (BN) rat was prepared. This antibody (1F119) binds to A membrane‐bound antigen present on DC from thoracic duct lymph, spleen, thymus, and lymph node. The antigen is present only in low density on 5% of splenic miicrophages (M&oS) and absent from peritoneal M&oS. In situ, the antibody exhibits a strong reactivity towards DC in the thymic medulla, whereas no reaction is observed with cortical cells. Furthermore, cells positive for 1F119 can be identified in T‐cell areas of spleen, lymph node, and Peyers' patches. lF119 was genetically restricted in that a strong reactivity was found with DC from rats of the RT1n and RT1u haplotypes, an intermediate reactivity with the RT1c haplotype, only a weak reactivity with the RT1l and RT1b haplotypes, and no reactivity with the RT1a and RT1k haplotypes. The relatively weak reactivity of 1F119 with respect to the RT1l haplotype also appeared from a weak binding of 1F119 to DC from Lewis rats, as was assessed by FACS analysis. This result was comparable to the binding of OX3 (RT1.Bl and RT1.Bu) to DC from BN rats. Studies performed on thymus sections of recombinant rat strains indicate that 1F119, despite its apparent specificity for DC, reacts with a polymorphic RT1.B product.
Defects of Autologous Mixed Lymphocyte Reaction‐Activated Immunoregulatory T Cells in Patients with Systemic Lupus Erythematosus
Authors: KOIDE J. , TAKEUCHI T. , HOSONO O. , TAKANO M. , ABE T.
Published: June 2006

The present study was undertaken to determine the nature of the immunoregulatory T‐cell defect after autologous mixed lymphocyte reaction (AMLR) activation in patients with systemic lupus erythematosus (SLE). Although AMLR was decreased in patients with SLE compared with normals, there was no difference in major proliferative cells (T4 cells and T4+JRA+ subset) in response to AMLR. Functional activity of AMLR‐stimulated T4 subsets in patients with SLE and normals was examined in helper and suppressor/inducer assay, using pokeweed mitogen (PWM)‐driven IgG synthesis. The T4+JRA− (helper) subset from SLE patients showed no greater activity than normals. However the T4+JRA+ (suppressor/inducer) subset from SLE patients showed decreased suppression induction compared with normals. This defect in the suppressor/inducer function was demonstrated even in patients with inactive SLR or in remission.
Monocyte Phenotype and Function in Patients with the Acquired Immunodeficiency Syndrome (AIDS) and AIDS‐Related Disorders
Authors: HAAS J. G. , RIETHMÜLLER G. , ZIEGLER‐HEITBROCK H. W. L.
Published: June 2006

The CD4 molecule, which is known to play an important role in the susceptibility of T lymphocytes to infection by the human immunodeficiency virus (HIV), is also expressed in small amounts on the surface of monocytes. Since monocytes can also be infected by the virus, we investigated peripheral blood monocytes of patients with the acquired immunodeficiency syndrome (AIDS). AIDS‐related complex (ARC), and HIV seropositive and seronegative haemophiliacs without symptoms for the expression of the CD4 molecule and for other functionally important surface molecules such as CD11 (C3bi receptor), transferrin receptor, Fc receptor, and the three major histocompatibility complex (MHC) class II antigens HLA‐DP. HLA‐DR, and HLA‐DQ. With immunofluorescence staining and flow cytometry no difference was found between patients and controls for the expression of the CD4 molecule and for the other antigens as assessed by the percentage of positive staining and the specific fluorescence intensity in a double marker analysis. The percentage of CD4+ monocytes was found to be 59.2±14.4% for 16 patients with AIDS and 52.9±12.8% for 12 healthy controls. Similar to our results on phenotype, we found no significant difference with respect to the production of tumour necrosis factor (TNF), in that monocytes of AIDS and ARC patients showed an increase in TNF secretion after stimulation with LPS comparable to controls.
Immunohistochemical Detection of the Membrane and Fluid‐phase Terminal Complement Complexes C5b‐9(m) and SC5b‐9
Authors: MOLLNES T. E. , HARBOE M.
Published: June 2006

Activation of the terminal pathway of complement on a membrane results in the generation of the membrane‐damaging terminal C5b‐9(m) complement complex, whereas the non‐lytic water‐soluble SC5b‐9 complex is formed when complement is activated in the fluid phase. Both forms of the terminal complement complex (TCC) can be immunohistochemically detected. but not distinguished, by antibodies recognizing neoantigens in the complexes. By means of monoclonal antibodies against C9 neoantigens and against the S‐protein. it was demonstrated that deposits of the TCC in tissue sections may be either in the form of C5b‐9(m) or SC5b‐9. The consequences of this for the interpretation of the histochemical data and the terminology of the two complexes are discussed.
T Lymphocytes Displaying Major Histocompatibility Complex‐Unrestricted Cytotoxicity after Activation by K46M, a Mitogenic Monoclonal Antibody against Leucoagglutinin‐Reactive Human T Lymphocyte Surface Components
Authors: VARGAS‐CORTES M. , BERZINS T. , HAMMARSTRÖM M. ‐L. , HAMMARSTRÖM S. , PERLMANN P.
Published: June 2006

Activation of human peripheral blood lymphocytes (PBL) with the mitogenic monoclonal antibody (MoAb) K46M, which recognizes 1‐5% of PBL, resulted in the expansion of cells with cytolytic activity. Thus, after culture of the activated lymphocytes in medium containing interleukin 2 (IL‐2), they lysed a variety of cultured cell lines. The majority of the activated lymphocytes reacted with MoAb to CD8, CD3, and to the T cell antigen receptor heterodimer (Ti) but not with antibodies to antigens expressed on natural killer (NK) cells. The cytotoxicity was not inhibited by MoAb to CD3 or Ti. However, the killing of K562, but not of other cell lines, was enhanced by three to four times in the presence of anti‐Ti antibodies. Anti‐CD3 or other control antibodies had no effect. Cold target inhibition experiments indicated that the cytolytic lymphocytes recognized closely related structures on the target cells. Phenotypically and functionally similar effector cells emerged after activation of PBL with the anti‐CD3 MoAb OKT3. Taken together, the results indicate that activation of PBL with MoAb K46M induces cytotoxic cells that differ from classical NK cells but that resemble mature cytotoxic T lymphocytes (CTL). However, unlike CTL, cytotoxicity was not MHC‐restricted and the conventional T‐cell receptor complex (CD3/Ti) appeared not to be involved in target cell recognition and cytolysis.
Generation of Large Granular Lymphocytes and Lymphocyte Subset Changes Linked with Cyclophosphamide‐Induced Eosinophilia in Rats—and the Effects of Ciclosporin
Authors: MATHIE I. H. , SEWELL H. F. , THOMSON A. W.
Published: June 2006

Administration of cyclophosphamide (Cy: 150 mg/kg i.p.) to rats 48 h before immunization with a T‐dependent antigen (ovalbumin) resulted in a striking absolute eosinophilia in blood, bone marrow, and secondary lymphoid organs after 10 to 14 days. This eosinophilia was preceded by a significant increase in the W3/25+/OX‐8+ (T helper/inducer to T cytotoxic/suppressor) ratio in lymph nodes and spleen and accompanied by a pronounced rise in splenic OX‐12+ (B cell) numbers. There was also a concomitant increase in cells with the morphology and immunophenotype (OX‐8+, OX‐19−) of large granular lymphocytes (LGL). It is suggested that the eosinophilia linked with the B lymphocytosis may be due to cell‐derived soluble factors, including a possible equivalent of eosinophil differentiation factor (EDF=interleukin 5), which also has B‐cell growth factor activity (BCGF II) in mice. Ciclosporin (CsA; 25 mg/kg/day per os) from the time of immunization, did not affect the incidence of W3/25+ cells in spleen or lymph nodes, but abrogated Cy‐induced eosinophilia and reduced the extent of B‐cell proliferation. In addition, CsA caused a further, marked increase in the incidence of OX‐8+, OX‐19− LGL within the spleen. The functional role(s) of these latter cells remains to be defined.
Comparative Studies on Tree Pollen Allergens
Authors: FLORVAAG E.
Published: June 2006

Visualization by autoradiography of specific IgE binding in crossed radioimmunoelectrophoresis (CRIE) and other 125I‐immunoautoradiography (IAR) techniques is done in two different ways; either by traditional direct autoradiography (D‐ARG), where the film is exposed to the 125I‐anti‐lgE incubated sample at room temperature, or by indirect autoradiography (ID‐ARG), applying intensifying screen, low‐temperature exposure and, eventually, pre‐exposure. This study confirmed that D‐ARG provided the benefits of simplicity and better image resolution with the disadvantage of prolonged exposure periods. ID‐ARG reduced the exposures needed to produce film image densities of 0.01 and 0.1 A540 nm (i.e. autoradiographic sensitivity (ARσ) and autoradiographic speed (ARs)) to 1/l8 and 1/55 respectively of the corresponding exposures in D‐ARG. The lowest detection limits for 125I in 24 h were 1.2 cpm mm−2 with the indirect and 6.8cpm mm−2 with the direct systems investigated. The major drawbacks of ID‐ARG were inferior image resolution and higher background levels, especially when pre‐exposure was included.
Influence of Processing by Erythrocyte C3b/C4b Receptors (CR1) on Binding of Immune Complexes to Raji Cells and Polymorphonuclear Granulocytes
Authors: RASMUSSEN J. MØLLER , JEPSEN H. H. , SVEHAG S‐E.
Published: June 2006

The binding of 125I‐labelled bovine serum albumin (BSA)‐anti‐BSA immune complexes (IC) to Raji cells and polymorphonuclear(PMN)cells in vitro was studied. The IC were reacted for 1 h at 37°C with normal human serum (NHS) diluted 1:2 in the presence or absence of human erythrocytes (E) before presentation for Raji cells or PMN cells. The IC showed a two to three fold increased binding to C3d, g receptors (CR2) on Raji cells, when E‐CR1 had been present during the reaction with NHS, compared to IC similarly reacted with NHS only. Blocking of the E‐CR1 by a polyclonal anti‐CR1 antibody reduced the subsequent binding of IC to Raji cells to the same level as that obtained with IC reacted with serum only. Binding to PMN granulocytes of IC reacted with NHS in the presence of E‐CR1 showed a 60% reduction compared to the binding of IC reacted with NHS only. It is concluded that interaction of complement‐reacted IC with CR1 on erythrocytes leads to a more efficient generation of CR2‐binding C3d, g‐containing IC with reduced reactivity to PMN cells.
Matching for Supertypic DR Epitopes Does Not Reduce Mixed Lymphocyte Culture Reactivity
Authors: NAGESSER S. K. , BOSCH M. L. , VAN ROOD J. J. , TERMIJTELEN A.
Published: June 2006

It was recently demonstrated that matching for the supertypic DR specificities DRw52 and DRw53 significantly improved graft survival in a group of retrospectively typed kidney transplant patients. We investigated whether this phenomenon was also reflected in vitro in the mixed lymphocyte culture (MLC) test system. MLC matrices were set up, but no effect of the matching between responder and stimulator for DRw52 and DRw53 was observed, although matching for the DR ‘private’ specificities (DR1‐DRw10) was significant. In responderstimulator combinations, too, which were mismatched for 1 DR antigen only, it did not matter whether or not the mismatched antigen on the stimulator was DRw52 or DRw53 compatible to the responder. These findings imply that matching for supertypic DR epitopes does not necessarily lead to reduced MLC reactivity.
Characterization of a Lectin in Human Plasma Analogous to Bovine Conglutinin
Authors: THIEL S. , BAATRUP G. , FRIIS‐CHRISTIANSEN P. , SVEHAG S.‐E. , JENSENIUS J. C.
Published: June 2006

The structural characteristics of a human plasma protein analogous to bovine conglutinin were studied. The protein was previously found to bind to complement‐reacted IgG in a calcium‐dependent and N‐acetyl‐D‐glucosamine‐inhibitable manner and it further shows cross‐reactivity with anti‐bovine conglutinin antibody. By gel permeation chromatography the conglutinin activity in human plasma was localized to fractions containing proteins of Mj at around 700,000. The conglutinin was localized by one ELISA for antigen determinants and by another for biological activity. When analysed by sodium dodecyl sulphate‐polyacrylamide gel electrophoresis (SDS‐PAGE) under non‐reducing conditions these fractions were shown to contain proteins of about 300,000. When human conglutinin‐like protein, partially purified by affinity chromatography, was analysed unreduced by SDS‐PAGE followed by western blotting, the cross‐reacting anti‐bovine conglutinin antibody bound to a protein with an Mr of 330,000. When the sample was reduced and alkylated before electrophoresis a band of 66,000 was immunostained. The 330,000 and 66,000 proteins were shown to be collagenase sensitive. 125I‐iC3b was seen to bind to the 330,000 band when incubated with western blots of partially purified human conglutinin.
Polyclonal Antibody Secretion during Acute Graft‐versus‐Host Disease
Authors: RINGDÉN O. , SUNDBERG B. , MARKLING L. , TOLLEMAR J.
Published: June 2006

Spontaneous plaque‐forming cells (S‐PFC) were followed in 67 bone marrow transplantation (BMT) recipients and 41 controls. Patients with no acute graft‐versus‐host disease (GVHD) had decreased IgA and IgM S‐PFC up to 7 weeks after BMT compared with controls. Patients with acute GVHD had increased lgG, IgA, and IgM PFC compared with controls and patients without GVHD during the first 4 weeks after BMT. The maximum number of S‐PFC increased with increasing severity of acute GVHD. However, at diagnosis of GVHD there was no difference in S‐PFC in patients who resolved their GVHD or in those who developed more severe GVHD. After 6 weeks, patients with acute GVHD had significantly decreased IgA and IgM S‐PFC compared with normal. No major changes in S‐PFC were induced during various infections. However, a patient who developed urticaria had a dramatic increase in S‐PFC. Patients studied more than a year after BMT had reduced IgM S‐PFC compared with controls. It is concluded that S‐PFC are redueed after BMT. but markedly enhaneed during acute GVHD.
Unique Immunological Behaviour of CD8+ (Suppressor T Cell) Leukaemia Cells
Authors: RAZIUDDIN S. , MADAN A. , DANIAL B. H.
Published: June 2006

A patient with chronic lymphocytic leukaemia and elevated serum IgM antibody is described. A multiparameter surface marker analysis of his peripheral blood lymphocytes demonstrated a unique phenotype of OKT3−, OKT11−, E‐rosetting+, OKT4−, OKT8+, OKIal+, OKCLL+, OKDR−, Tac+, characterizing the disease as suppressor (CD8+) T cell chronic lymphocytic leukaemia. Because of the uncommon phenotype and the abnormal serum immunoglobulin pattern, in vitro functional assays were performed that showed decreased mitogenic response to the phytohaemagglutinin, but increased response to concanavalin A. However, these leukaemic T cells demonstrated phytohaemagglutinin‐specific suppressor cell activity on normal blood lymphocytes. In vitro functional studies indicated that a defect in the patient's T cells may cause IgM hypergammaglobulinaemia. The regulatory function of the patient's T cells on immunoglobulin synthesis by normal B cells was found to be mediated by a soluble factor secreted from neoplastic T cells.
Macrophages and Dendritic Cells in Antigen‐Induced Arthritis
Authors: DIJKSTRA C. D. , DÖPP E. A. , VOGELS I. M. C. , VAN NOORDEN C. J. F.
Published: June 2006

Two non‐lymphoid cell types play an important role in the pathogenesis of arthritis, i.e. the ‘classical’ macrophage and the antigen‐presenting dendritic cell [33]. In the present sludy, the roles of both cell types are studied in antigen‐induced arthritis of the rat knee joint. Cryostat sections of whole, unfixed, undecalcified knee joints were used for immunohistochemical staining of non‐lymphoid cells and lymphocyte subsets. For the demonstration of the different types of non‐lymphoid cells, monoclonal antibodies against rat macrophages (ED1. ED2, and ED3) and against Ia antigen were used with an immunoperoxidase method. The results show in an overalls view of the arthritic joint the different sites of action of the classical macrophages on the one hand and the Ia‐positive dendritic cells on the other. Classical macrophages were mainly found in the superficial layers of the synovium bordering joint space and articular cartilage. Dendritic cells and T cells of the helper phenotype were mainly found in clusters surrounding small blood vessels within the synovium. These clusters express the immunological background of the antigen‐induced arthritis and may well be responsible for the continuation of the arthritic process.
Inhibition of Natural Killer Cell Cytotoxicity by a Monoclonal Antibody Directed against Adhesion‐Mediating Protein gp 90 (CD18)
Authors: AXBERG I. , RAMSTEDT U. , PATARROYO M. , BEATTY P. , WIGZELL H.
Published: June 2006

Contact is required between the effector natural killer (NK) or cytotoxic killer T cell and its corresponding target in order for efficient lysis to occur. Several surface molecules of different types are involved in this process. Here we could show that Fab fragments from a murinemonoclonal antibody reacting with gp 90, the human leucocyte common antigen CD18, are extremely efficient in blocking human NK of killer T cells, regardless of whether the target has or does not have the antigen. In contrast, no impact of the antibody was observed when the effector cells were of murine origin, again regardless of whether the target cell did or did not display the leucocyte common antigen. The inhibition could be shown to occur at the level of blockage of target‐conjugate formation. This means that the functional display of effector/target gp 90 on the effector but not the target cell is necessary for efficient lysis to occur both in NK and killer T cell systems.
Inhibition of T Cell Cytolytic Potential by Concanavalin A: A Result of Activation?
Authors: MILTENBURG A. M. M. , MEIJER‐PAAPE M. E. , DAHA M. R. , PAUL L. C.
Published: June 2006

We investigated the effects of concanavalin A (Con A) on T cell‐mediated lympholysis. Human cytotoxic T cell lines were generated from peripheral blood and these lines were shown to lyse Leetin‐coated K562 target cells. Addition of soluble Con A to the assay resulted in a dosedependent inhibition of the cytolysis. Preincubation experiments demonstrated that this inhibitory effect was exerted at the effector cell level. F(ab')2 fragments of WT32, a monoclonal extent. We furter showed that Con A strongly inhibited the cytolysis exerted by alloantigen‐specific, major histocompatibility complex (MHC)‐restricted cytotoxic T cell lines against their specific targets. On the other hand, con A had no clear inhibitory effect on the cytotoxicity of freshly isolated peripheral blood mononuclear cells against K562 target cells. We hypothesize that Con A‐induced inhibition blood of cytotoxicity may be explained by a direct triggering of the lytic potential of activated T cells.
Oestrogen‐Induced Suppression of Collagen Arthritis
Authors: LARSSON P. , HOLMDAHL R.
Published: June 2006

Immunization of female Lewis rats with bovine type II collagen induces a severe polyarthritis with an incomplete penetration. Castration of the rats increased the incidence to 94% compared with 50% among sham‐operated controls. When castrated female rats were implanted with silicon capsules containing β‐oestradiol they developed arthritis with a delayed onset and a decreased severity compared with castrated rats implanted with empty Silastic capsules. The levels of anti‐type II collagen auto‐antibodies were not affected by castration or oestrogen treatment. These findings show that oestrogen suppresses the development of collagen arthritis in rats and that this effect is mediated by mechanisms other than anti‐type II collagen autoantibodies.
Lymphotoxin‐Induced Growth Stimulation of Diploid Human Fibroblasts in the Presence and Absence of Gamma Interferon
Authors: HOFSLI E. , AUSTGULEN R. , NISSEN‐MEYER J.
Published: June 2006

In the present study we investigated the effect of lymphotoxin (LT) on the growth of human diploid fibroblasts, in the presence and absence of gamma interferon (IFN‐γ). Recombinant LT (rLT) had a growth stimulatory effect on diploid human FS‐4 fibroblasts. This growth‐stimulatory effect was reduced in the presence of recombinant IFN‐γ (rIFN‐γ). LT thus has a similar effect on diploid fibroblasts as tumour necrosis factor (TNF).
Intrathymic Tolerance Induction: Determination of Tolerance to Class II Major Histocompatibility Complex Antigens in Maturing T Lymphocytes by a Bone Marrow‐Derived Non‐Lymphoid Thymus Cell
Authors: ZEPP F. , CUSSLER K. , MANNHARDT W. , SCHOFFER O. , SCHULTE‐WISSERMANN H.
Published: June 2006

Two new experimental approaches were established to analyse the influence of the thymus on tolerance induction to major histocompatibility complex (MHC) antigens: The aim of the first experiment was to perform successful transplantation of adult allogeneic thymus tissue into nude mice, an attempt that has been unsuccessful in the past. Tolerance for the MHC genotype of a prospective thymus graft recipient (A) was induced in mice of strain B by injection of (AxB) splenocytes during the neonatal period. Adult thymic tissue obtained from these allogeneic donors (B) were grafted into the nude mice of strain A. The allogeneic thymus was accepted by the nude mice and immunoreconstitution was achieved. Subsequently the recipients developed tolerance to the MHC antigens of the allogeneic thymus donor as proved by mixed lymphocyte cultures and the acceptance of skin grafts. The second experiment was designed to determine which la‐positive thymic compartment participates in confering tolerance to MHC antigens in maturing T lymphocytes. Chimaeric thymus grafts were created by transplantation of neonatal thymus (A) into allogeneic nude mice (B) for a period of 8 weeks. The graft was populated with host bone marrow‐derived la antigen‐positive cells. The chimaeric thymuses consisting of type A epithelium but populated with both type A and B lymphocytes and non‐lymphoid cells (i.e. la‐positive maerophages and dendritic cells), were newly transplanted into nude mice of strain A. The engraftment led to immunological reconstitution and the nude mice acquired tolerance to the MHC antigens expressed by the allogeneic ta‐positive cells populating the chimaeric graft. Irradiation ofthe chimacric thymus prior to transplantation allowed transplantation of chimaeric thymus devoid of living thymocytes but still populated with functionally intact la‐positive non‐lymphoid cells. Transplantation of irradiated chimaeric thymuses resulted in immunoreconstitution and induced exactly the same allotolerance pattern as described above. The results demonstrate that not thymus epithelial cells but a bone‐marow‐derived non‐lymphoid thymus cell, most likely the la‐antigen‐positive thymic macrophage of dendritic cell, is responsible for the induction of tolerance to MHC antigens in developing T lymphocytes.
Interstitial Pneumonitis and Hepatitis after Transfer of Bone Marrow Cells Bearing the Ipr Gene to Irradiated Recipients: A Disease Due to Large Granular Leueocytes?
Authors: PIGUET P. F. , IZUI S. , JANIN‐MERCIER A. , KAPANCI Y. , VASSALLI P.
Published: June 2006

Mice bearing the ‘auto‐immune’Ipr gene develop a lympho‐proliferative disease associated with the production of various antibodies, Lethally irradiated recipients were grafted with bone marrow cells (BMC) from syngeneie mice with or without the Ipr gene. After 6 months, the survivors were 0/24 and 16/20 for the recipients of lpr and normal BMC respectively. The mortality rate was independent of the presence of T lymphocytes among the BMC. Histological evaluation showed that hepatitis, interstitial pneumonitis. and sclerosis of lymphohaemopoietic organs were the major causes of death for the recipients of lpr BMC, Hepatitis was associated with an increase in the number of liver interstitial cells (LIC) from about 2x106) up to about 107 cells per liver. The LIC associated with the hepatitis were composed of polymorphonuclear leucocytes and large mononuclear leueocytes, showing phenotypic (i.e. Thy. 1−, asialo GM1, presence of cytoplasmic granules) and functional (i.e, non‐phagocytic and cylolytic) properties of NK cells. The disease can be distinguished both from the spontaneous disease of the lpr mice (by the absence of‘lpr cells'and of anti‐DNA antibodies) and from craft versus host disease hy the absence of cutaneous and intestinal lesions. It may represent a model of tissue injury mediated by large granular leucocytes.
Removal of Endotoxin from Culture Media by a Polymyxin B Sepharose Column
Authors: MØLVIG J. , BAEK L.
Published: June 2006

The in vitro study of monocytes (Mo) poses several problems. Minor contamination with endotoxin (ET) of media ami utensils as well as adherence to glass or plastic surfaces may activate the cells and cause pronounced production of monokines. Many commercially liquid culture media were found to contain ET in concentrations above 25x10−12 g/ml. A simple system for the removal of ET from media and solutions was established by use of a comniercially available Polymyxin B Septiarose gel, To measure the lipopolysaccharide (LFS) binding capacity of the gel. known concentrations of LPS were added to culture media, which were passed through a column consisting or the Polymyxin B Sepharose gel. The content of ET and added LPS in media was measured hy the Limulus amoehocyte lysatc (LAL) test before and after passage of the column. The LPS‐binding capacity of the gel was approximately 2.4 × 10 g/l0 ml. The biological activity of contaminating ET and added LPS in media, before and alter passage of the column, was also characterized by the capacity of the media to induce interleukin l (IL‐1) secretion in human Mo cultures. The content of IL‐l in Mo culture supernalants was determined by the mouse thymocyte costimulatory(LAF) assay. By comparison of the activity of ET in these different biological systems, it was demonstrated that 15‐20 × 10−12 g/ml of ET stimulate human Mo cultures lo IL‐1 secretion.
Fibroblast Growth‐Stimulatory Activity Released from Human Monocytes
Authors: AUSTGULEN R. , ESPEVIK T. , NISSEN‐MEYER J.
Published: June 2006

Human monoeytcs release fibroblast growth‐stimulatory activity. In this study tumour necrosis factor (TNF) has been identified as a major contributor to the monocyte‐derived fibroblast growth‐stimulaiory activity. A neutralizing monoclonal antibody (MoAb) against recombinant TNF (rTNF) inhibited growth of FS‐4 fibroblasts and skin biopsy fibroblasts induced by monocyte supernatants, indicating that TNF was involved in the stimulation. Optimal growth of FS‐4 fibroblasts was induced by monocyte supernatants at dilutions which cointained TNF at a concentration between 1.6 × 10−6 and 4.0 × 10−5μg/ml, less growth being induced at higher TNF concentrations. Contrary to this, no optimal concentration interval was found lor rTNF, since increasing rTNF concentrations always resulted in increased growth stimulation. It also appeared that natural TNF in the monocyte supernatants induced growth at a much lower concentration than rTNF tested in the absence of monocyte supernatant.
Differences in the Kinetics of Histamine Formation and Granulation of Human Basophilic Cells from Bone Marrow, Peripheral Blood, and Cord Blood
Authors: AHLSTEDT S. , HAMMARSTROM I. , INTO‐MALMBERG M.‐B. , LEHTONEN P.
Published: June 2006

Human bone marrow, cord blood, and peripheral blood comntain progenitor cells, which during culture mature to histamine‐containing basophilie cells. In bone marrow the histamine content per Alcian blue staining basophilie cell was low before culture. Cultivaiion of BML cells resulted in increased histamine levels in cultures(P<0.05). whereas the basophilic cells did not increase significantly. Cell cultures were stimulated with conditioned medium (CM) produced with allergen‐slimulated cells from atopies and from the Mo T leukaemie cell line. Cells from cultures slimulaled with CM contained less histamine calculated per basophilie cell than did those from unstimulted cultures (P<5.05), There was a significant correlation between the numbers of basophilic cells and the histamine content in cells on day 0 prior to cultivation and after 14 days of cultivation (P<0.01 and P<0.05 respectively). In cord blood there was a correlation between the numhers of basophilie cells and the histamine levels prior to cultivation (P<0.05). During cultivation the number of basophilie cells increased five‐lold (P<0.02), whereas the histamine levels did not inercase resulting in a decreased histamine level per basophilie cell (P<0.02). In peripheral blood the basophilic cells contained the highest levels of histamine. The numbers of hasophilie cells and their conntent of hisiamine showed good correlation both hefore and after unstimtilated and stimulated cultivation (P<0.01). whereas unstimulated cultures did not show such correlation. The results indicate the presence of different proportions of progenitor cells in bone marrow, cord blood. and peripheral blood. all with different ability to produce histamine and become granulated basophilic cells.