A hematopoietic stem cell in bone marrow requires constant signaling to prevent differentiation. Which process maintains stem cell pluripotency in this microenvironment?

💡 Explanation

Hematopoietic stem cells rely on niche factors secreted by surrounding cells to remain undifferentiated. Niche factor receptor activation triggers intracellular signaling cascades maintaining pluripotency, because these signals inhibit differentiation pathways; therefore, receptor activation sustains stemness rather than other epigenetic modifications directly silencing genes.

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