Effects of W^v andNf1 genotypes on splenic architecture in primary and secondary recipients.

(A-D) Low-power view (original magnification × 10) of spleen sections from primary recipients of transplanted fetal liver cells from the 4 F2 experimental groups outlined in “Study design.” Recipients of transplanted Nf1^+/+;W^v+/+and Nf1^+/+;W^v/W^v fetal liver cells show a normal distribution of red pulp and white pulp (A-B). In contrast, recipients of transplantedNf1^−/−;W^v/W^v orNf1^−/−;W^v+/+ fetal liver cells showed expansion of the red pulp with loss of normal splenic architecture (C-D). (E-H ) A representative low-power view (original magnification × 10) of spleen sections from secondary recipients of transplanted low-density mononuclear cells harvested from the bone marrow of primary recipients of transplanted fetal liver cells from the 4 F2 experimental groups. Secondary recipients of transplantedNf1^+/+;W^v+/+ andNf1^+/+;W^v/W^v LDMNCs show a normal distribution of red pulp and white pulp (n = 7 for each genotype) (E-F). In contrast, secondary recipients of transplantedNf1^−/−;W^v/W^v orNf1^−/−;W^v+/+ LDMNCs showed expansion of the red pulp with loss of normal splenic architecture (n = 7 for each genotype) (G-H).