Constitutive expression of TGF-bêta1, interleukin-6 and interleukin-8 by tumor cells as a major component of immune escape in human ovarian carcinoma

Tumors could use several mechanisms to coexist with the host's immune system or to protect themselves from an immune response. Thus, insufficient expression of cell surface molecules on tumor cells, which are important for T cell recognition or activation, could lead to induction of a state of tolerance. Tumor cells could also produce cytokines that would inhibit the immune response and allow tumor progression. Here, we studied, in vitro, the cell surface expression of immunologically important molecules in seven ovarian carcinoma (OVCA) cell lines and the constitutive expression of cytokines. All OVCA cell lines expressed MHC class I molecules, ICAM-1 and LFA-3 adhesion molecules, necessary to induce a specific cytotoxic T-cell response, as well as the CD40 costimulatory molecules. Conversely, the lack of the dominant costimulatory molecules, CD80 (B7.1) and CD86 (B7.2) could be a possible explanation of poor immunogenicity of OVCA tumors. Immunosuppressive TGF-beta1 was detected at the mRNA level in all cell lines but was weakly secreted in supernatants. By contrast, IL-10 was never found. Most of them constitutively produced IL-8 and IL-6, two cytokines known as tumor promoting factors whereas the proinflammatory cytokines TNF-alpha, IL-1beta and GM-CSF were rarely produced. Data from this study could be useful for designing new strategies of immunotherapy to improve immunogenicity and/or limit protumor cytokine production.     

Charles Darwin’s bird collection and ornithological knowledge during the voyage of H.M.S. “Beagle”, 1831–1836

This paper analyses Charles Darwins bird collection and the ornithological knowledge he derived from it during the voyage of H.M.S. Beagle. Darwin collected 468 bird skins, 10 detached parts of the lesser rhea, and the nests and eggs of 16 different taxa as well as 14 whole birds and 4 parts of birds which he preserved in spirit. He labelled these specimens with a number tag only, cross-referring the number to a notebook entry. Partly because of his limited ornithological knowledge and partly because he was confronted at times with entirely unknown birds, Darwin was often unable to apply the correct generic designations and gave his South American specimens English and Spanish names from literature and the local tongues, as well as the scientific generic names of European birds. Back home, it was John Gould, the prominent ornithologist of the Zoological Society of London, who made sense of Darwins collection, among his many other scientific achievements correctly identifying the Galápagos finches as a group of closely related birds. Darwins bird collection did not receive much attention in the latter part of the 19th century. Most of the specimens had their original labels removed and replaced by ones of the custodian institution. Today, original Darwin specimens stemming from the Beagle voyage are to be found in at least eight different institutions, but almost half of the bird specimens Darwin collected on the Beagle voyage are not accounted for. The appendix to this paper lists for the first time all the birds which Darwin collected during the voyage. Darwins famous book On the origin of species hardly draws upon any ornithological examples from his voyage on the Beagle. Nevertheless, Darwin contributed much to ornithology. His collection contained 39 new species and subspecies of birds, mainly described by Gould, and some birds from populations now extinct, and he also made a few very good field observations, published in the sections of The Zoology of the Voyage of H.M.S. Beagle dedicated to birds.