Altered synthesis of laminin 1 and absence of basement membrane component deposition in (beta)1 integrin-deficient embryoid bodies.

Basement membranes are the earliest extracellular matrices produced during embryogenesis. They result from synthesis and assembly into a defined supramolecular architecture of several components, including laminins, collagen IV, nidogen, and proteoglycans. In vitro studies have allowed us to propose an assembly model based on the polymerisation of laminin and collagen IV in two separate networks associated together by nidogen. How nucleation of polymers and insolubilisation of the different components into a basement membrane proceed in vivo is, however, unknown. A most important property of several basement membrane components is to provide signals controling the activity of adjacent cells. The transfer of information is mediated by interactions with cell surface receptors, among them integrins. Mouse genetics has demonstrated that the absence of these interactions is not compatible with development as deletion of either laminin (gamma)1 chain or integrin (beta)1 chain lead to lethality of mouse embryos at the peri-implantation stage. We have used embyoid bodies as a model system recapitulating the early steps of embryogenesis to unravel the respective roles of laminin and (beta)1 integrins in basement membrane formation. Our data show that there is formation of a basal lamina in wild-type, but not in (beta)1-integrin deficient, embryoid bodies. Surprisingly, in the absence of (beta)1 integrins, laminin 1 was not secreted in the extracellular space due to a rapid switch off of laminin (alpha)1 chain synthesis which normally drives the secretion of laminin heterotrimers. These results indicate that (beta)1 integrins are required for the initiation of basement membrane formation, presumably by applying a feed-back regulation on the expression of laminin (alpha)1 chain and other components of basement membranes.

[In vitro activity of Mercurius cyanatus complex against relevant pathogenic bacterial isolates]. / In-vitro-Aktivität von Mercurius cyanatus-Komplex gegenüber relevanten pathogenen Bakterienisolaten.

The antimicrobial activity of mercurius cyanatus complex (Oligoplex) and its components Mercurius cyanatus D5, Echinacea angustifolia D1, Ailanthus glandulosa D3, Ammonium bromatum D3, Baptisia tinctoria D3, Euspongia officinalis D2, alcohol 5% (dilution: D1 = 1: 10, D2 = 1 : 100 etc.) was tested in vitro by serial dilution tests against 105 clinical isolates (grampositive/negative, aerobes and anaerobes with relevance for pharyngitis). The bactericidal activity was compared with that of vancomycin when appropriate. One component of the composition (Mercurius cyanatus) exerted a considerable bactericidal activity against S. pyogenes, S. agalactiae, S. pneumoniae, S. aureus, E. faecalis in serial dilutions of the clinical relevant concentration D5. However, growth of H. influenzae, Bacteriodes sp. and Actinobacillus actinomycetemcomitans was not inhibited by Mercurius cyanatus and any other component of the composition. The composition, however, exerted a bactericidal range similar to that of Mercurius cyanatus, but less efficient. Analysis of the bactericidal effect of Mercurius cyanatus and vancomycin revealed comparability for S. pyogenes, S. agalactiae, S. pneumoniae, S. aureus and E. faecalis for vancomycin concentrations of 0.063-2 mg/l, which are clinically relevant.

[Immunoactive effects of various mistletoe lectin-1 dosages in mammary carcinoma patients]. / Immunaktive Wirkung verschiedener Mistellektin-1-Dosierungen in Mammakarzinom-Patientinnen.

Cellular aspects of the immunomodulating activity of a proprietary mistletoe extract (Eurixor) standardized for mistletoe lectin-1 (ML-1) were investigated in patients suffering from mammary carcinoma (n = 20). Regular subcutaneous injections of the different dosages (0.5 and 1.0 ng ML-1/kg body weight, twice a week, for 5 weeks) yielded statistically significant increases of defined peripheral blood lymphocyte subsets (helper T-cells, natural killer (NK)-cells) which are generally believed to be involved in antitumor activity. Moreover, administration of either ML-1 concentration resulted in enhanced expression of activation markers such as interleukin-2 receptors and HLA/DR-antigens on peripheral blood T-lymphocytes. This study suggests that regular subcutaneous administration of both ML-1 concentrations (0.5 and 1.0 ng/kg body weight) can efficiently stimulate the cellular immune system of cancer patients.

Influence of propionibacterium avidum KP-40 on the proliferation, maturation, emigration and activity of thymocytes and monocytes.

Inactivated cells of Propionibacterium avidum KP-40 could be shown to induce thymocyte proliferation and maturation in BALB/c-mice after intraperitoneal administration of the optimal immunomodulating dosage (1 mg per mouse). The increase in thymus weight and thymocyte numbers per mg organ weight was most pronounced and statistically significant 10 days after P. avidum KP-40 administration. Determinations of lymphatic subsets revealed a considerable up-regulation of mature cells expressing helper/inducer (L3T4+) or cytotoxic/suppressor (Lyt-2+) phenotypes and immature cells presenting both L3T4+/Lyt-2+ antigens. Obviously, P. avidum KP-40 administration accelerated murine thymocyte proliferation and maturation. Counts of BALB/c-mouse peripheral blood lymphocytes (PBL) and monocytes (PBM) revealed statistically significant increases after P. avidum KP-40 administration with peak values after 6-10 days. The determination of activated PBL (expressing interleukin-2 receptors) or PBM (expressing MAC-3 antigens) proved that P. avidum KP-40 induced a potent immunostimulation since counts of these cells were significantly enhanced after P. avidum KP-40 treatment.

[Immunoactive action of mistletoe lectin-1 in relation to dose]. / Immunaktive Wirkung von Mistellektin-1 in Abhängigkeit von der Dosierung.

Galactoside-specific mistletoe lectin-1 (ML-1) was isolated by affinity chromatography from proprietary mistletoe extract and checked in BALB/c-mice for its immunoactive potency. To investigate the optimal immunomodulating dosage, ML-1 (0.5, 1.0, 2.5, 5.0 ng/kg body weight, b.w.) was subcutaneously administered for three subsequent days followed by another injection 48 h later. These studies proved that injections of 1 ng ML-1/kg b.w. induced optimal immunomodulation, since thymocyte proliferation, maturation and emigration were significantly enhanced in this murine model as compared to non-treated control mice. Further on, counts of peripheral blood lymphocytes and monocytes as well as expression of relevant activation markers on these cells revealed significant increases after ML-1 (1 ng/kg b.w.) administration. However, increase of cell counts and activity of peritoneal macrophages were less pronounced but still statistically significant for this ML-1 concentration. Determination of immune responses after low dose ML-1 treatment (0.5 ng/kg b.w.) presented relevant (partly statistically significant) increases, too. However, high dose ML-1 treatment (2.5, 5.0 ng/kg b.w.) did not enhance (but suppress) relevant immune functions. For future clinical/therapeutical treatment strategies, ML-1 dosages ranging from 0.5-1.0 ng/kg b.w. may be supposed to be optimal.

Immunoprotective activity of the galactoside-specific mistletoe lectin in cortisone-treated BALB/c-mice.

Hydrocortisone-acetate (HA)-treatment of BALB/c-mice induced a profound suppression of the lymphatic immune system with statistically significant decreases of thymocyte proliferation and maturation rates as well as peripheral blood lymphocyte (PBL) counts. To check its putative immunoprotective/immunorestoring activity, the optimal immunomodulating dosage of commercially available mistletoe extract standardized for the galactoside-specific mistletoe lectin (ML-1) was regularly administered (1 ng ML-1 per kg body weight; subcutaneously). As compared to counts of thymic lymphatic subsets of HA-treated mice, a considerable up regulation of mature cells expressing helper/inducer (L3T4+) as well as cytotoxic/suppressor (Lyt-2+) phenotypes and immature cells expressing both antigens (L3T4+/Lyt-2+) could be found after ML-1 co-administration. Counts of BALB/c-mouse peripheral blood mononuclear cells also revealed statistically significant increases after ML-1 co-administration, as compared to HA-treated animals. Accordingly, ML-1 treatment may be supposed to restore the lymphatic system after immunosuppressive corticoid treatment and thus this treatment may be of great benefit to patients.

Combined immunomodulation (Propionibacterium avidum KP-40) and lectin blocking (D-galactose) prevents liver tumor colonization in BALB/c-mice.

The protective effect of combined treatment (immunomodulation with Propionibacterium avidum KP-40; liver lectin blocking by D-galactose administration) on the liver colonization of RAW 117-H10 lymphosarcoma was investigated in BALB/c-mice. Both, immunomodulation with P. avidum KP-40 as well as liver lectin blocking by D-galactose treatment significantly decreased the number of liver tumor colonies in this experimental model. However, the combination of P. avidum KP-40 and D-galactose obviously proved to be superior to each monotherapy since the liver colonization by RAW 117-H 10 lymphosarcoma could be completely inhibited.

Enhancement of immune responses to suramin correlates with antineoplastic activity in BALB/c-mice.

The antiparasitic naphthylurea suramin (SUR) could be shown to exert immunomodulating and antimetastatic activity in BALB/c-mice. Regular intraperitoneal administration of SUR yielded significant weight gain of spleen and significant enhancement of peritoneal macrophage activity in chemiluminescence assays. The number of thymocytes per mg organ weight did not show evident differences in control and SUR treated groups; however, determinations of lymphocyte subsets revealed up-regulation of mature cells expressing helper/inducer (L3T4) or cytotoxic/suppressor (Lyt-2) phenotypes but down-regulation of immature cells presenting both L3T4/Lyt-2 antigens. Accordingly, administration of SUR obviously accelerated murine thymocyte maturation. Counts of BALB/c-mice peripheral blood lymphocytes (PBL) revealed evident (but statistically non-significant) increases after SUR administration. The determination of activated T-cells expressing interleukin (Il-2) receptors further proved that SUR induced a potent immunostimulation since these cells were significantly enhanced after treatment. To evaluate the antimetastatic activity of SUR, sarcoma L-1 cells were intravenously inoculated into BALB/c-mice. In this model system the number of experimental lung metastases significantly decreased, as compared to control mice which received injections of saline solution. Accordingly, SUR can be regarded as an immunomodulating and antimetastatic substance which seems to be promising for clinical trials in oncology.

Thymocyte proliferation and maturation in response to galactoside-specific mistletoe lectin-1.

Commercially available mistletoe extract standardized for the galactoside-specific mistletoe lectin-1 (ML-1) could be shown to induce thymocyte proliferation and maturation in BALB/c-mice after regular subcutaneous administration of the optimal immunomodulating dosage (1ng lectin/kg body weight). The increase in thymocyte numbers per mg organ weight was statistically significant. Determinations of thymic lymphatic subsets revealed considerable up-regulation of mature cells expressing helper/inducer (L3T4) or cytotoxic/suppressor (Lyt-2) phenotype and immature cells presenting both (L3T4/Lyt-2) antigens. Thus, administration of ML-1 accelerated murine thymocyte proliferation and maturation. Counts of BALB/c-mouse peripheral blood lymphocytes (PBL) revealed evident (but statistically non-significant) increases after ML-1 administration. The determination of activated PBL expressing interleukin (Il)-2 receptors proved, however, that ML-1 induced a potent immunostimulation since these cells were significantly enhanced after ML-1 administration.

[Comparative studies on the immunoactive action of galactoside-specific mistletoe lectin. Pure substance compared to the standardized extract]. / Vergleichende Untersuchungen zur immunaktiven Wirkung von Galaktosid-spezifischem Mistellektin. Reinsubstanz gegen standardisierten Extrakt.

Comparative Studies on the Immunoactive Potency of Galactoside-specific Lectin from Mistletoe/Pure substance against standardized extract. Cellular and humoral aspects of the immunomodulating activity of the galactoside-specific lectin from mistletoe (ML-1) were investigated in cancer patients suffering from mammary carcinoma and compared to the immunoactive potency of a proprietary mistletoe extract standardized for ML-1 (ML-1 stand., Eurixor). Regular subcutaneous injections of the optimal dose of ML-1 and ML-1 stand. (1 ng/kg body weight; twice a week; for 4 weeks) yielded statistically significant increases of certain lymphocyte subsets (helper T-lymphocytes, natural killer (NK)-cells) which are generally believed to be involved in antitumor activity. Moreover, administration of either ML-1 preparation resulted in enhanced expression of interleukin (Il)-2 receptors on lymphatic cells and significantly increased serum levels of defined acute phase reactants (c-reactive protein, haptoglobin, C3 complement) as indicator of cellular and humoral activity. In vitro, exposition of human lymphocytes to ML-1 and ML-1 stand. resulted in enhanced expression of Il-2 receptors, which substantiated the capacity of both ML-1 preparations to affect immunological parameters within the host defense system. The effects of ML-1 and ML-1 stand. were comparable.

Antibacterial in vitro-activity of meropenem against 200 clinical isolates in comparison to 11 selected antibiotics.

The antimicrobial activity of meropenem, a new parenteral carbapenem, was tested in vitro by an agar dilution method against 200 clinical isolates (gram-negative/positive aerobes and anaerobes). Meropenem was compared with imipenem, ceftazidime, cefotaxime, piperacillin, ciprofloxacin, gentamicin; and metronidazole, cefoxitin, chloramphenicol, clindamycin, vancomycin when appropriate. Meropenem and imipenem exhibited an extended spectrum of activity with low minimal inhibitory concentrations (MICs). Only one strain each of Enterococcus faecium and Pseudomonas (Xanthomonas) maltophilia were resistant. Of the carbapenems, imipenem was slightly more active against Enterococcus faecalis, Streptococcus agalactiae, and staphylococci, but meropenem was obviously more active against enterobacteriaceae and Clostridium perfringens. Both, meropenem and imipenem had similar activities towards Pseudomonas aeruginosa, Acinetobacter calcoaceticus, Streptococcus pyogenes and Bacteroides sp. All other antibiotics tested were less potent than the carbapenems with the exception of ciprofloxacin which generally exhibited similar antibacterial activities, except for anaerob microorganisms.

[Urinary tract infections caused by Staphylococcus saprophyticus. Increased incidence depending on the blood group]. / Harnwegsinfektionen durch Staphylococcus saprophyticus. Gehäuftes Auftreten in Abhängigkeit von der Blutgruppe.

Between 1. 1. 1988 and 31. 12. 1990, greater than or equal to 10 colony-forming units of Staph. saprophyticus were isolated from 55 of a total of 20,000 urine samples went in. The isolates from these 55 patients (52 women, 3 men; mean age 29 [17-58] years) were tested for specific adhesion molecules (lectins) to discover their relationship to blood-group characteristic carbohydrates. 52 of the 55 patients (94.5%) were blood-group A or AB (average for Middle-Europeans: 48.2%). Haemagglutination and inhibition tests with the Staph. saprophyticus isolates demonstrated in all instances N-acetylgalactosamine (GalNAc) specificity of the surface lectins. These findings support the hypothesis that the carbohydrate pattern of Blood group A (terminal GalNAc) is important for the colonization of exposed organs by Staph. saprophyticus with GalNAc-specific lectins.