In Vitro Angiogenic Activity of RNA From Leukemic Lymphocytes

Abstract

RNA was extracted from leukemic lymphocytes by a fluorocarbon method, and primary cultures of human amniotic cells were exposed to the lymphocyte RNA. Angioid tubular and cordon-like structures in branching out and criss-cross patterns with budding ends developed in these cultures within 7 to 12 days of the first exposure. Although there was no opportunity to study preparations from nonleukemic lymphocytes, extracts of normal peripheral blood cells and blood rich in granulocytes had no angiogenic effects. In view of the recent renewal of interest in tumor and tissue angiogenic factor as well as in angiogenic activity by transformed lymphocytes, in addition to the intriguing angioblastic component of Lukes-Rappaport immunoproliferative syndromes, this work may point to the ribonucleic acid nature of the vessel-forming principle. Various cell-differentiating properties of RNA preparations have been repeatedly described, and thus it is not altogether surprising that lymphocyte angiogenic factor may originate in RNA.

Extracellular Functional Noncoding Nucleic Acid Bioaptamers and Angiotropin RNP Ribokines in Vascularization and Self‐Tolerance

“…For the numerous aspects of these phenomena, see, for example, Refs. 4–6,11–15,21–24,33–50,63,69–74,77. Some factors involved (Table 1) may reflect some details.…”

“…Tissue vascularization comprises a complex interplay of multiple processes, various morphogenic and cellular mechanisms and phenotypes, including epigenetic phenotypical variations (outlined below). For the formation of a functional vascular network, they are dependent not only on different genes, but are subject to an array of aspects, including exogenous, environmental and endogenous humoral, cellular, and tissue‐patterning factors and functions 4–6,21–24,37,40–50,70–74,77 . Intrinsically, in early embryonal development, (arterial/venous) vessel specification, positional and network patterning information are considered genetically determined in that several genes seem to be involved 6,22,40,43,82 .…”

“…For the formation of a functional vascular network, they are dependent not only on different genes, but are subject to an array of aspects, including exogenous, environmental and endogenous humoral, cellular, and tissue-patterning factors and functions. [4][5][6][21][22][23][24]37,[40][41][42][43][44][45][46][47][48][49][50][70][71][72][73][74]77 Intrinsically, in early embryonal development, (arterial/venous) vessel specification, positional and network patterning information are considered genetically determined in that several genes seem to be involved. 6,22,40,43,82 A single master gene, if existing at all, awaits to be disclosed.…”

“…40 Several mechanisms associated with beneficial or harmful pathophysiologic re-and degenerative vascularization processes at or remote to intrinsic reaction sites were disclosed, mostly being found associated with monocyte/macrophage infiltration. [4][5][6][9][10][11][12][13][14][15][21][22][23][24][25][34][35][36]46,47,73,74 They include vasculogenesis, lymphangiogenesis, and (hem-)angiogenesis with arteriogenesis, veniogenesis, anastomogenesis, and further subtypes (e.g., sprouting and intussusceptive angiogenesis). [4][5][6]13,[21][22][23][24][40][41][42][43][44] They all follow an initiation process ("angiogenic switch").…”

“…They are dependent on intrinsic and extrinsic epigenetic factors associated with the genome, epigenesis, epigenetics, and epigenome. 5,6,14,15,[40][41][42][43][44][45][69][70][71][72][73][74] The terms concern different explanations as to how phenotypical information on gene regulation and expression is adopted from one cell's or organism's generation to the next. [65][66][67][68][69] Epigenesis deals with gradual development of phenotypic variations and transitions between them and implies germ line and somatic genetic processes.…”