Blood formation in the african lungfish, under normal conditions and under conditions of prolonged estivation and recovery

Abstract

The blood cells of the African lungfish, Protopterus ethiopicus, are very large and resemble those of urodeles. Leucocytes are especially plentiful and rich in variety, including eosinophils, special eosinophils, [meta‐eosinophils] with atypical granules, monocytes, thrombocytes, lymphocytes, and basophils. The chief hemocytopoietic organs are the spleen, intestine, and kidneys. The lungfish spleen, embedded in the wall of the stomach, represents an intermediate phylogenetic stage between the disperse intra‐enteral type of the hagfish and the compact extra‐enteral type of other vertebrates. Erythrocytes are formed in the spleen pulp, granulocytes in the granulocytopoietic organ of the intestine and in the capsules of kidneys, gonads, and spleen. Thrombocytes and monocytes are differentiated in the spleen and general circulation. Basophils arise in the spleen and intestine. Lymphoid cells of all types arise in the spleen. Evidence is presented bearing upon the hemocytopoietic capacity of the various types. Cells with [Russell bodies] also occur in the spleen. In lungfishes subjected to long periods of dry estivation, erythrocytopoiesis practically ceases. Granulocytes, however, appear to play an important rǒle, possibly in fat metabolism. The large variety of meta‐eosinophils, a unique feature of the lungfish, appears to be associated with the habit of estivation. Recovery from estivation may show numerous amitoses of erythrocytes in the general circulation. Other cells which divide in this manner are young thrombocytes, granulocytes, monocytes, and lymphoid hemoblasts.

Anti-viral immune responses in a primitive lung: Characterization and expression analysis of interferon-inducible immunoproteasome subunits LMP2, LMP7 and MECL-1 in a sarcopterygian fish, the Nigerian spotted lungfish (Protopterus dolloi)

“…We selected these two tissues for the following reasons: i) the lung because of its importance in the transition of vertebrates from water to land; ii) the kidney because it had the highest constitutive expression of the immunoproteasome genes and because it is known as one of the main hematopoietic organs in lungfish (Delaney et al, 1976; Jordan and Speidel, 1931). …”

Splenic hemopoiesis of the platypus (Ornithorhynchus anatinus): Evidence of primary hemopoiesis in the spleen of a primitive mammal

“…Primary hemopoiesis in the spleen occurs commonly in the elasmobranchs (particularly rays) and in some archaic species of teleosts such as the lungfish (Jordan and Speidel, 1931;Tanaka, 1985a) and Polypterus (Tanaka, 1985b), but there are no descriptions of primary hemopoiesis in the spleen of mammals up to this time. Phylogenetically, the spleen was probably the earliest hemopoietic organ to develop in the ancestors of the vertebrates.…”

“…Phylogenetically, the spleen was probably the earliest hemopoietic organ to develop in the ancestors of the vertebrates. An early (probably the earliest) form of the spleen may be represented by the hemopoietic tissues that have been noted within the intestinal wall of two species of fish: the lamprey (Jordan and Speidel, 1930;Tanaka et al, 1981) and the lungfish (Jordan and Speidel, 1931;Rafn and Wingstrand, 1981;Tanaka, 1985a). This form of the spleen has been designated as an intestinal spleen.…”

“…However, splenic hemopoiesis in rodents is regarded as secondary to the primary hemopoiesis which occurs in the bone marrow. Phylogenetically, the spleen most likely developed as the primary hemopoietic organ, exemplified by the intestinal spleen that occurs in the lungfish (Jordan and Speidel, 1931;Rafn and Wingstrand, 1981;Tanaka, 1985a). The primitive vein (the primary vein) preserved in the lungfish spleen is considered the most important factor influencing the generation of blood cells (Tanaka, 1985a).…”

The blood circulation system in human spleen: is it open or closed?

“…В филогенезе белая и красная пульпа впервые обособляется у двоякодышащих рыб в виде желудочной селезенки [1]. Затем у хрящевых и костистых рыб формируется самостоятельный орган кроветворения -селезенка [2].…”