Expansion of granulocyte population in RA⁻mice.

(A) Spleens from 17-week-old mice fed with the RA⁺ or RA⁻ diet. (B) Histology of spleens from RA⁺and RA⁻ mice (17 weeks old). The border between the white pulp and red pulp is discernible in the RA⁺ spleen (i, iii), but not in the RA⁻ spleen (ii, iv) due to overpopulation of granulocytes. (Original magnification: i and ii, × 100; iii and iv, × 400). (C) Cytology of bone marrow cells (i, ii) and peripheral blood (iii, iv) (original magnification × 630). Myeloid cells at various stages of maturation were increased in the RA⁻ bone marrow, relative to the RA⁺ samples. Panels iii and iv illustrate hypersegmented nuclei in granulocytes of RA⁻ peripheral blood, not found in RA⁺ cells.