Tagesperiodik,Revierverhalten und Beutefang der Geißelspinne Admetus pumilio C. L. Koch im Freiland*

Auf einer Fläche von ca. 40 × 60 m eines Regenwaldes bei Manaus/Amazonas wurden über 30 Admetus pumilio untersucht, sowie Temperatur, Feuchte und Helligkeit im Biotop registriert. Man findet immer nur ein Tier in einer Höhle am Fuß großer Bäume; nahezu jedes derartige Versteck ist besetzt. Der Aktivitätsverlauf zeigt im Freiland 3 Aktivitätsschübe: der abendliche dient der Nahrungsaufnahme, der nachmitternächtliche dem Verlassen des engeren Reviers zu Partnersuche oder zum Höhlenwechsel, der morgendliche zur Rückkehr ins Versteck. Der Aktivitätsbeginn gegen 16 Uhr ist endogen, das Aktivitätsende gegen 6.30 Uhr weitgehend exogen bestimmt. Der Rückzug in die Höhle am Morgen erfolgt bei 10fach niedrigerer Helligkeit als der Auszug aus dieser am Abend. Adulte Geißelspinnen behalten über mehrere Wochen die gleiche Höhle bei; beobachtet wurde bis zu 65 Tagen. Innerhalb eines untersuchten Umkreises von 7—10 m können sie sich hervorragend orientieren — vermutlich olfaktorisch. Die Beutefanghandlung wird beschrieben und die Orientierung hierbei analysiert. Zwei mechanorezeptorische Systeme werden nach- oder nebeneinander wirksam: Trichobothrien auf den Schreitbeinen leisten die Fernorientierung und dirigieren die Annäherung an die Beute bis in den Wirkungsbereich der Tastbeine, die die Orientierung im Nahbereich übernehmen, vor allem beim Packen der Beute. Die kutikularen Haarsensillen auf den Beinen werden kurz beschrieben.     

Clinical and immunological responses in metastatic melanoma patients vaccinated with a high-dose poly-epitope vaccine

Background

Safety and cellular immunogenicity of rising doses and varying regimens of a poly-epitope vaccine were evaluated in advanced metastatic melanoma. The vaccine comprised plasmid DNA and recombinant modified vaccinia virus Ankara (MVA) both expressing a string (Mel3) of seven HLA.A2/A1 epitopes from five melanoma antigens.

Methods

Forty-one HLA-A2 positive patients with stage III/IV melanoma were enrolled. Patient groups received one or two doses of DNA.Mel3 followed by escalating doses of MVA.Mel3. Immunisations then continued eight weekly in the absence of disease progression. Epitope-specific CD8+ T cell responses were evaluated using ex-vivo tetramer and IFN-γ ELISPOT assays. Safety and clinical responses were monitored.

Results

Prime-boost DNA/MVA induced Melan-A-specific CD8+ T cell responses in 22/31 (71%) patients detected by tetramer assay. ELISPOT detected a response to at least one epitope in 10/31 (32%) patients. T cell responder rates were <50% with low-dose DNA/MVA, or MVA alone, rising to 91% with high-dose DNA/MVA. Among eight patients showing evidence of clinical benefit—one PR (24 months+), five SD (5 months+) and two mixed responses—seven had associated immune responses. Melan-A-tetramer+ immunity was associated with a median 8-week increase in time-to-progression (P = 0.037) and 71 week increase in survival (P = 0.0002) compared to non-immunity. High-dose vaccine was well tolerated. The only significant toxicities were flu-like symptoms and injection-site reactions.

Conclusions

DNA.Mel3 and MVA.Mel3 in a prime-boost protocol generated high rates of immune response to melanoma antigen epitopes. The treatment was well tolerated and the correlation of immune responses with patient outcomes encourages further investigation.     

Backbone resonance assignment of Alt a 1, a unique β-barrel protein and the major allergen of Alternaria alternata

Alt a 1 is the major allergen of the fungus Alternaria alternata and can be found in the cell wall of its spores. It is a cysteine linked homodimeric protein with a unique β-barrel fold as recently revealed by X-ray crystallography. Despite the elucidation of its structure, its biological function remains unknown. For Alternaria-sensitized patients, contact leads to respiratory allergy and in severe cases to asthma-related death. Here we report the sequence-specific Alt a 1 backbone ¹H, ¹⁵N and ¹³C chemical shift assignment.     

In vivo antitumor efficacy of interleukin-21 in combination with chemotherapeutics

Interleukin-21 (IL-21) is a class I cytokine with antitumor properties due to enhanced proliferation and effector function of CD8⁺ T cells and natural killer (NK) cells. Here we have explored the magnitude and time-course of cytostatics-induced lymphopenia in mice and investigated whether treatment with cytostatics influences the antitumor effect of IL-21 in mouse tumor models. We show that pegylated liposomal doxorubicin (PLD), irinotecan and oxaliplatin induced transient lymphopenia, whereas 5-fluorouracil (5-FU) transiently increased lymphocyte counts. B cells were more sensitive than T cells towards irinotecan and oxaliplatin. Additive antitumor effects were observed after combining IL-21 with PLD, oxaliplatin and to less extent 5-FU but not irinotecan, and larger effect was observed when IL-21 administration was postponed relative to chemotherapy, suggesting that these agents may transiently impair immune function. However, the chemotherapies did not significantly alter the levels of circulating regulatory T cells and only marginally affected the ability of CD8⁺ T cells to respond to IL-21 measured as increased granzyme B mRNA. Our results show that IL-21 therapy can be successfully combined with agents from different chemotherapeutic drug classes, i.e. topoisomerase II inhibitors (PLD), anti-metabolites (5-FU) and platinum analogs (oxaliplatin) provided that IL-21 therapy is delayed relative to chemotherapy.     

Immunohistochemistry,glycosylation and immunosuppression of glycodelin in human ovarian cancer

Glycodelins (Gds) are glycoproteins with a gender specific glycosylation. Glycodelin A (GdA) is primarily produced in endometrial and decidual tissue and secreted to amniotic fluid. Glycodelins were also identified in several cancer types, including serous ovarian cancer. Gds act as a T-cell inhibitor and are involved in inactivation of human monocytes. With a Gd peptide antibody, derived from a 15 amino acid sequence of human Gd and in situ hybridization experiments, the expression of Gd in serous, mucinous, endometrioid and clear cell ovarian tumors was identified. In contrast to former investigations with antibodies against GdA, a positive immunohistochemical reaction for Gd was observed in all forms of epithelium ovarian cancer. These results were confirmed with in situ hybridization. In addition, Gd is expressed in granulose cell tumors, a non-epithelial form of ovarian cancer. Furthermore, Gd was purified from ascites fluid of ovarian cancer patients. Ascites Gd showed significant differences in its structure of sialyl Lewis-type oligosaccharides compared to GdA. Additionally, ascites Gd inhibits IL-2 stimulated proliferation of peripheral blood leucocytes and inhibits adhesion of SLe^X-positive cells to E-selectin. Therefore, Gd could act as an inhibitor of lymphocyte activation and/or adhesion in ovarian cancer. U. Jeschke, I. Mylonas and C. Kunert-Keil contributed equally to this work.     

Functional sulfurtransferase is associated with mitochondrial complex I from Yarrowia lipolytica, but is not required for assembly of its iron-sulfur clusters

Here, we report that in the obligate aerobic yeast Yarrowia lipolytica, a protein exhibiting rhodanese (thiosulfate:cyanide sulfurtransferase) activity is associated with proton pumping NADH:ubiquinone oxidoreductase (complex I). Complex I is a key enzyme of the mitochondrial respiratory chain that contains eight iron-sulfur clusters. From a rhodanese deletion strain, we purified functional complex I that lacked the additional protein but was fully assembled and displayed no functional defects or changes in EPR signature. In contrast to previous suggestions, this indicated that the sulfurtransferase associated with Y. lipolytica complex I is not required for assembly of its iron-sulfur clusters.     

Osmoregulation, immunolocalization of Na+/K+-ATPase, and ultrastructure of branchial epithelia in the developing brown shrimp, Crangon crangon (Decapoda, Caridea)

Aspects of osmoregulation including salinity tolerance, osmoregulatory capacity, location of transporting epithelia, and the expression of the enzyme Na+/K+-ATPase were investigated in the developing brown shrimp, Crangon crangon (L.), from the North Sea. Early developmental stages and large juveniles were exposed to a wide range of salinities for measurement of hemolymph osmolality and survival rates. In media ranging from 17.0 per thousand to 32.2 per thousand, salinity tolerance was generally high (survival rates: 70%-100%) in all developmental stages, but it decreased in media <10.2 per thousand. Zoeal stages and decapodids slightly hyperregulated at 17.0 per thousand and osmoconformed in media > or =25.5 per thousand. At 10.2 per thousand, these stages showed high mortality, and only juveniles survived at 5.3 per thousand. Juveniles hyperregulated at 10.2 per thousand and 17.0 per thousand, osmoconformed at 25.5 per thousand, and hyporegulated in media > or =32.2 per thousand. Large juveniles hyperregulated also at 5.3 per thousand. Expression of the Na+/K+-ATPase and ion-transporting cells was located through immunofluorescence microscopy and transmission electron microscopy. In zoeae I and VI, a strong immunoreactivity was observed in cells of the inner epithelia of the branchiostegites and in epithelial cells lining the pleurae. Their ultrastructure showed typical features of ion-transporting cells. In decapodids and juveniles, ionocytes and expression of Na+/K+-ATPase remained located in the branchiostegite epithelium, but they disappeared from the pleurae and appeared in the epipodites. In large juveniles, the cells of the gill shaft showed positive immunolabeling and ultrastructural features of ionocytes. In summary, the adult pattern of osmoregulation in C. crangon is accomplished after metamorphosis from a moderately hyperosmoconforming decapodid to an effectively hyper-/hyporegulating juvenile stage. Salinity tolerance and osmoregulatory capacity are closely correlated with the development of ion-transporting cells and the expression of Na+/K+-ATPase.     

Revision of the monogenean subfamily Thoracocotylinae Price, 1936 (Polyopisthocotylea: Thoracocotylidae), with the description of a new species of the genus Pseudothoracocotyla Yamaguti, 1963

Members of the subfamily Thoracocotylinae are gastrocotylid monogeneans of Spanish mackerels (scombrid fishes of the genus Scomberomorus) from warm to warm-temperate seas around the world. We revise the diagnosis of the subfamily and recognise two genera and three species as valid. The genus Paradawesia Bravo Hollis & Lamothe Argumedo, 1976 is synonymised with Thoracocotyle MacCallum, 1913, and Dawesia Unnithan, 1965 and Methoracocotyle Lebedev, 1984 are synonymised with Pseudothoracocotyla Yamaguti, 1963. Thoracocotyle crocea MacCallum, 1913 (syns T. paradoxica Meserve, 1938 and Paradawesia bychowskyi Bravo Hollis & Lamothe Argumedo, 1976) is recorded from two species of Scomberomorus in the eastern Pacific (California to Peru) and four in the western Atlantic (South Carolina to Brazil). Pseudothoracocotyla ovalis (Tripathi, 1956) Yamaguti, 1963 (new syns Dawesia indica Unnithan, 1965, D. incisa Lebedev, 1970, Methoracocotyle scomberomori (Young, 1968) Lebedev, 1984, M. gigantica (Rohde, 1976) Lebedev, 1984 and Thoracotyle indica (Unnithan, 1965) Murugesh, 1995) is recorded from the gills of seven species of Scomberomorus from the Indo-west Pacific (eastern South Africa north to the Persian Gulf, and east to Fiji). Pseudothoracocotyla whittingtoni n. sp. is described from an eighth Indo-west Pacific scomberomorid, S. munroi, in Australian waters.     

Growth efficiencies of freshwater bacterioplankton

The growth efficiency of freshwater bacteria was examined in continuous cultures. One series of experiments was carried out using generation times from 50 to 200 hours and aged, normal, and enriched media, all of natural origin. Another series of experiments examined the bacterial growth efficiency during the growth season in eutrophic Frederiksborg Slotssø, in relation to changes in the planktonic communities and to factors controlling the bacterial incorporation of ³H-thymidine. Attachment of bacteria to the inner surfaces of the experimental flasks was examined using various types of bottles, adding glass tubes to the bottles, and measuring ³H-thymidine incorporation and direct cell counts of attached and free-living bacteria. Attachment of bacteria varied, and in one example up to 36% of the thymidine incorporation was by attached bacteria after 4 days. It was calculated that 36% of attached bacteria caused an underestimation of the growth efficiency of 11%. The mean growth efficiency tended to decrease with generation time using enriched medium (47 to 19%) and aged medium (35 to 12%), and tended to decrease with medium quality (enriched > normal > aged media) from 37% to 27%. The only significant difference in growth efficiency occurred in relation to generation time, in samples with enriched medium (unpaired t-test, P < 0.05). The overall mean value for all generation times and media was 30% (SEM = 3%, n = 24). From April to October, the growth efficiency was determined 5 times in samples from Frederiksborg Slotssø. The overall mean value was 31% (SEM = 3%, n = 30), and there was no significant change in the growth efficiency during the period measured. In June, three bioassay experiments revealed that carbon limitation controlled bacterial incorporation of ³H-thymidine, whereas additions of phosphate and nitrate did not change the incorporation rates. The narrow range of growth efficiencies obtained in this study (mean 31%, SEM = 2%, n = 54) suggests that changes in substratequality in the media applied and in the eutrophic samples examined causes only subtle changes in the growth efficiency.