Fig. 3

ALV-J blocked the differentiation and maturity of CD117⁺chB6⁺ B cell progenitors. a Schematic representation of bursal B cell morphogenesis and gene expression. b IHC staining for chB6 antigen in the bursas of Fabricius and spleens of mock-infected chickens and chickens infected at ED 6 using mouse anti-chB6 Ab. Fewer B cell clones (as shown in the inset) were present in the bursal follicles and splenic nodules of infected chickens; the medulla was absent in the bursal follicles of chickens infected at ED 6. Sections are the consecutive sections from those used for histological examination, which were stained by BCIP/NBT (black purple) (magnification: ×400, ×100). c Quantitation of b; **p < 0.01, ***p < 0.001, two-way ANOVA was performed. d Flow cytometry analysis for the differentiation of B cell progenitors. In this test, the mock-infected chickens (n = 15) and chickens infected at ED 6 (n = 15) were used. e Quantitation of d; **p < 0.01, ***p < 0.001, two-way ANOVA was performed. f Flow cytometry analysis for the percentage of ALV-J-infected B cells, which showed that inoculating with ALV-J during the embryonic period can cause more B cells to be infected. In this test, mock-infected chickens (n = 10), chickens infected at ED 6 (n = 10), and chickens infected at D 1 (n = 10) were used. g IHC staining for ALV-J antigen in the bursas of Fabricius of chickens infected at ED 6. Sections were stained by DAB (Brown) and counterstained by haematoxylin (magnification: ×1000). h Quantitation of f; ***p < 0.001, unpaired t-test was performed to determine the statistical difference