The role of peritoneal T lymphocytes and macrophages in the initiation of stress erythropoiesisin vivo following a single massive blood loss in mice

Abstract

Peritoneal ceils of anemic donors enriched with macrophages at the expense of Tcell lysis using anti-Thy-1.2 monoclonal antibodies are capable of triggering various routes of terminal erythroid differentiation characteristic of stress erythropoiesis during their adoptive transfer to normal syngeneic recipients. Stimulation of the proliferation of polychromatophilic erythroblasts and initiation of mitoses in oxyphilic erythroblasts are regulated by interacting T ceUs and macrophages, and the "reserve erythropoiesis" mainly by macrophages. Key Words: stress erythropoiesis; peritoneal cells; reserve erythropoiesis; blood lossIn mammals with severe anemias the erythroid precursors, on reaching the terminal stages, form red ceils as a result of terminal differentiation by various routes. One of these routes, "reserve erythropoiesis," is an emergency route of accelerated differentiation of ceils providing for the survival of the organism during the early periods after massive blood loss. It consists in the omission of severn terminal stages and the rapid release of morphologically immature cells into the blood [2,3,[6][7][8]. A transito13" increase in the content of basophilic erythroblasts (BE) in the bone marrow paralleled by a decrease of their mitotic activity may be considered as a bone marrow marker of "reserve erythropoiesis" [3,7]. Moreover, blood loss enhances polychromatophilic erythroblasts (PE) amplification and initiates mitoses in oxyphilic erythroblasts (OE), which normally almost never divide [1,3].

Changes in erythropoiesis in normal mice induced by transplantation of peritoneal cells from syngeneic donors with long-term sodium arsenite intoxication

“…Reserve erythropoiesis induced by massive blood loss and adoptive transfer of peritoneal cells is characterized by accumulation of BE in the bone marrow with simultaneous inhibition of their mitotic activity, increased PE and OE counts and corresponding mitotic indices, and a higher erythrocyte/eukocyte ratio [1][2][3]. Thus, peritoneal cells play an important role in the regulation of immediate response of erythropoiesis to various stress factors.…”

“…Adoptive transfer of peritoneal cells nonstimulated with inflammatory agents from anemic mice induces reparative erythropoiesis in intact syngeneic recipients [1][2][3]. However, there is no evidence on whether peritoneal cells can induce compensatory changes in the erythropoiesis in response to other factors impairing erythropoiesis.…”

Ability of peritoneal exudate cells to trigger various mechanisms of erythroid differentiation at different terms after massive blood loss in mice

“…Unstimulated with inflammatory antigen, peritoneal exudate cells (60-70% macrophages and 25% lymphocytes [6]) obtained from mice with massive blood loss gain the ability to trigger reparative erythropoiesis in the bone marrow of syngeneic recipients [1,2]. In this case, specific features typical of reserve erythropoiesis, initiation of OE proliferation, and enhancement of PE proliferation are observed.…”

“…After severe anemia, erythrocyte pool is restored by 3 various differentiation pathways [1][2][3][4][5]7]. At the terminal stage of anemia, the reserve (emergency) pathway of erythropoiesis is manifested in transitory accumulation of basophilic erythroblasts (BE) in the bone marrow accompanied by a decrease in their mitotic activity [5,7].…”

The past, present, and future of research on the regulation of nonlymphoid cell proliferation by lymphoid cells

“…Splenic T lymphocytes of partially hepatectomized mice treated with specific anti-T-lymphocyte sera during the period of their highest morphogenetic activity were found to lose this activity, whereas a similar treatment of B lymphocytes did not affect splenocyte activity [9]. Although the evidence that morphogenetic function and regenerative information transfer are accomplished by T lymphocytes is overwhelming, it must still be noted that they perform this function and transfer more effectively in cooperation with macrophages, as was shown most clearly in experiments with regenerating hematopoietic tissue [14].…”