Immunohistochemical and morphologic analysis of human fetal muscle and neural cells using tissue-specific markers and emergence of functional hematopoietic progenitors.

Light microscopy was used to visualize cells comprising human muscle (Ai) and neural (Bi) tissues, showing morphologic features associated with these tissue types. Human muscle tissue specificity was analyzed by immunohistochemistry for the expression of muscle-specific markers recognizing heavy chain of myosin (Aii) and the nuclear DNA binding factor, myogenin (Aiii), whereas human neural tissue demonstrated expression of neural progenitor-specific marker, nestin (Bii) and MAP-2 (Biii), respectively. A representative panel of multilineage hematopoietic colonies derived from muscle (Aiv) and neural (Biv) tissues cultured in the presence of HGF together with BMP-4 and EPO is shown. Human hematopoietic colony types generated from muscle and neural tissues include erythroid burst-forming unit (BFU-E), CFU-granulocyte (G), -macrophage (M), and tetrapotent mixed colonies (granulocyte, erythroid, macrophage, megakaryocyte [GEMM]). Similar results were obtained from 9 independent samples of muscle and neural tissue samples. Magnification × 200.