@article{MerzFliednerLehrnbecheretal.1990, author = {Merz, H. and Fliedner, A. and Lehrnbecher, T. and Sebald, Walter and M{\"u}ller-Hermelink, H. K. and Feller, A. C.}, title = {Cytokine expression in B-cell non-Hodgkin lymphomas}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-62539}, year = {1990}, abstract = {No abstract available}, subject = {Biochemie}, language = {en} } @article{LehrnbecherMerzSebaldetal.1991, author = {Lehrnbecher, T. and Merz, H. and Sebald, Walter and Poot, M.}, title = {Interleukin 4 drives phytohemagglutinin-activated T cells through several cell cycles: no synergism between interleukin 2 and interleukin 4}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-62491}, year = {1991}, abstract = {Cell kinetic studies of T cells stimulated with the interleukin 2 (11-2), D-4, or both lymphokines were performed with conventional [3H] thymidine incorporation and with the bivariate BrdU/Hoechst technique. 11-2 and 11-4 are able to drive phytohemagglutininactivated T cells through more than one cell cycle. Neither synergistic nor inhibitory efl'ect on T -cell proliferationwas seen for the stimulation with both 11-2 and 11-4 as compared with the effect ofll-2 alone. The quantitative data ofthe cell cycle distribution ofphytohemagglutininactivated T cells suggestthat the population ofll-4-responsive cells is at least an overlapping population, if not a real subset of the ·population of the 11-2-responsive cells.}, subject = {Biochemie}, language = {en} } @article{KruseLehrnbecherSebald1991, author = {Kruse, N. and Lehrnbecher, T. and Sebald, Walter}, title = {Site-directed mutagenesis reveals the importance of disulfide bridges and aromatic residues for structure and proliferative activity of human interleukin-4}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-62505}, year = {1991}, abstract = {Mutant proteins (muteins) of human lnterleukin-4 (llA) were constructed by means of in vitro mutagenesis. The muteins were expressed in E. co/1, submitted to a renaturation and purification protocol and analysed for biological activity. Exchange of the cysteines at either position 46 or 99 which form one of the three disulfide bridges resulted. in a nearly co•mplete loss · of biological actiyity and an unstable protein. The exchange of tyrosine 124 also inactivated the protein, while a mutation of tyrosine 56 left some residual activity. Exchange of the other four cysteines or of · the single tryptophane had smaller etTects.}, subject = {Biochemie}, language = {en} } @article{TonyLehrnbecherMerzetal.1991, author = {Tony, H. P. and Lehrnbecher, T. and Merz, H. and Sebald, Werner and Wilhelm, M.}, title = {Regulation of IL-4 responsiveness in lymphoma B cells}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-62520}, year = {1991}, abstract = {The responsiveness to IL-4 with and without costimulation with anti-IgM antibodies or phorbolester was studied in 35 cases of low grade non-Hodgkin Iymphoma by analyzing enhancement of CD23 and HLA dass li expression. The predominant phenotype responds directly to IL-4. Separate differentiation states can be distinguished according to coordinate or differential upregulation of CD23 and HLA dass II molecules by IL-4 alone, and differences in responsiveness to anti-IgM antibodies. A particular subgroup of B-lymphoma cells defines a separate stage of B-eeil differentiation. They fail to express high affinity binding sites for IL-4 and accordingly do not respond to IL-4- mediated signals. Cross-linking membrane lgM receptors or direct activation of protein kinase C via phorbolester induces IL-4 receptor expression and subsequent IL-4 reactivity.}, subject = {Biochemie}, language = {en} } @article{LehrnbecherPootOrschescheketal.1994, author = {Lehrnbecher, T. and Poot, M. and Orscheschek, K. and Sebald, Walter and Feller, A. C. and Merz, H.}, title = {Interleukin 7 as interleukin 9 drives phytohemagglutinin-activated T cells through several cell cycles; no synergism between interleukin 7, interleukin 9 and interleukin 4}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-62438}, year = {1994}, abstract = {The effects of the interlenkins IL-7 and IL-9 on cell cycle progression were investigated by conventional [3H]thymidine incorporation and by the bivariate BrdU/Hoechst technique. 8oth IL· 7 and IL-9 drive phytohemagglutinin-activated T cells through more than one cell cycle, but IL-7 wasmorepotent on cell cycle progression than IL-9. Neither synergistic nor inhibitory effects were seen between various combinations of the lymphokines IL-7, IL-9 and IL-4 compared to each lymphokine alone. When T cells are activated with phytohemagglutinin for 3 days, all or most IL-4 responsive cells respond to IL-7 as weil, whereas only a part of IL-7 responders are IL-4 responders. In contrast, when T cells are activated with phytohemagglutinin for 7 days, the quantitative data of the cell cycle distribution soggest that the population of IL-7 responders is at least an overlapping, if not a real subset of the population of the IL-4 responders.}, subject = {Biochemie}, language = {en} }