HLA-G: Too Much or Too Little? Role in Cancer and Autoimmune Disease

HLA-G is a non-classical HLA class I molecule with immunomodulatory properties. It was initially described at the maternal-fetal interface, and it was later found that this molecule was constitutively expressed on certain immuneprivileged tissues, such as cornea, endothelial and erythroid precursors, and thymus. The immunosuppressive effect of HLA-G is exerted through the interaction with its cognate receptors, expressed on immunocompetent cells, like ILT2, expressed on NK, B, T cells and APCs; ILT4, on APCs; KIR, found on the surface of NK cells; and finally, the co-receptor CD8. Because of these immunomodulatory functions, HLA-G has been involved in several processes, amongst which organ transplantation, viral infections, cancer progression, and autoimmunity. HLA-G neo-expression on tumors has been recently described in several types of malignancies. In fact, tumor progression is tightly linked to the presence of the molecule, as it exerts its tolerogenic function, inhibiting the cells of the immune system and favoring tumor escape. Several polymorphisms in the 3’UTR region condition changes in HLA-G expression (14bp and +3142C/G, among others), which have been associated with both the development and outcome of patients with different tumor types. Also, in recent years, several studies have shown that HLA-G plays an important role in the control of autoimmune diseases. The ability of HLA-G to limit the progression of these diseases has been confirmed and, in fact, levels of the molecule and several of its polymorphisms have been associated with increased susceptibility to the development of autoimmune diseases, as well as increased disease severity. Thus, modulating HLA-G expression in target tissues of oncology patients or patients with autoimmune diseases may be potential therapeutic approaches to treat these pathological conditions.

Lineal Megalithic Rock Scripts as precursors of Iberian and other lineal Mediterranean/Euro African ancient writings: the case of Fuerteventura (Canary Islands, Spain)

Lineal Megalithic/Paleolithic Lineal signs/lines may have a variety of purposes or representations. Some authors have proposed they represent sky, planets and stars and their movements, space/time representations or others, including letters/syllables or symbols/events. Some are painted, other incised; the latter are relatively more common in Megalithic scripts. Man is “writing” or creating handmade figures on stones /rocks and other supports, which sometimes have intentionally been polished since Paleolithic times: at least 70,000 years BP (Blombos Cave, South Africa). Megalithic script is named because it is associated to megalithic structures, although not exclusively. Von Petzinger 40,000 years old “symbols” and/or writing are extended worldwide in Paleolithic caves and other rocks. Man connection was worldwide in Paleolithic times. Canary Islands incise or picketed lineal writing exists with a transcribed and translated meaning collection of signs (Ibero-Guanche or Latin inscriptions and Lybic ones). Also, other African/European/Mediterranean lineal scripts there exist and examples are given in the present paper. Fuerteventura Island contains in addition many small or bigger stones and rocks with these Paleolithic/Megalithic incised lines all over its territory. About timing in which these stones that were incised by man, we are only referring to a kind of stone crafting. However, we do not discard that they were made by man several thousand years BP. Some Paleolithic/Megalithic scripts are mixed with clear Iberian semi-syllabary signs in Fuerteventura and other Canary Islands. They may reflect the evolution of more ancient Megalithic scripts to lineal writings like those detailed in the present paper and others. Finally, writing concept should be redefined whenever more precise data and dating be available.

The Saharo-Canarian Circle: The forgotten Prehistory of Euro African Atlantic façade and its lack of eastern demic diffusion evidences

Canarians, North Africans and Iberians show a close genetic relatedness. Greeks have a Sub-Saharan gene input according to HLA and other autosomic markers. Also, there is a genetic kinship between both Atlantic Euro Africans and North African/Arabic people. This is concordant with a drying humid Sahara Desert, which may have occurred about 6,000 years BC, and the subsequent northwards emigration of Saharan people may have also happened in Pharaonic times. This genetic input into Atlantic and Mediterranean Europe/Africa is also supported with Lineal Megalithic Scripts in Canary Islands (as well as in Iberia) together with simple Iberian semi-syllabary rock inscriptions both at Canary Islands and Ti-m Missaou (Algeria, Central southern Sahara). Lineal African/European scripts are found in certain languages scripts like Berber/Tuareg, Iberian, Runes, Etruscan, Bulgarian (Sitovo and Gradeshnitza, 6,000 years BP), Italian Old Scripts (Lepontic, Venetic, Raetic), Minoan Lineal A and Vinca scripts (Romania, Serbia, Greece, Bulgaria, about 4,000 years BP). The possibility that Megalithic Lineal Scripts have given rise to these languages lineal writing is feasible because admixture of languages rock scripts and Megalithic Lineal Scripts have been found. Thus, resistance of Canarian aborigines (Guanches) to Carthage, Rome and Arabs left a bulk of Canarian-Saharan information which is used to study both Saharan and Canarian Prehistory, and also Atlantic and Mediterranean beginning of European and other civilizations: this preserved prehistoric inheritance may be named the “Saharo-Canarian Circle” of prehistoric knowledge. Also, linguistics-epigraphy, physical anthropology, archaeology, and domesticated cattle shows a close North Africa-Iberia Mesolithic/Neolithic relationship and demonstrates that the demic diffusion model does not exist in Iberia. Also, Tassili Sahara paintings of domesticated cattle appear 1,000 years before those agricultural practices started at Middle East. Finally, it is also inferred that circum-Mediterranean contacts during thousand years between ice and desert constructed Mediterranean cultures from Canary Islands to Ancient Great Persia and this is the origin of Classical Mediterranean cultures that was later exclusively attributed to Rome and Greece.