TABLE 1.

Frequencies of IgA-secreting cells in intestinal and nonintestinal lymphoid tissues of RV-infected SCID mice following reconstitution with peritoneal exudate cells, B1, or B1 plus CD4⁺ T cells^a

Transferred cells	Analyzed cells	Mean no. ± SEM		% ASC/IgSC
		ASC count	IgSC count
PEC	LP	1.2 × 104 ± 3 × 103	2 × 105 ± 6 × 103	6
	MLN	200 ± 53	6 × 104 ± 2 × 104	0.4
	Spleen	25 ± 5	1.8 × 103 ± 940	1.4
B1	LP	0	1.5 × 104 ± 402	0
	MLN	0	5.4 × 104 ± 8 × 103	0
	Spleen	0	342 ± 166	0
B1/CD4+ T	LP	180 ± 53	3.4 × 104 ± 5.5 × 103	0.5
	MLN	125 ± 4	3.6 × 104 ± 3.3 × 103	0.3
	Spleen	6 ± 1	195 ± 4	3

^aPEC, peritoneal exudate cells; LP, lamina propria cells; MLN, mesenteric lymph node cells. RV-infected SCID mice were reconstituted with unseparated peritoneal exudate cells, sorted B1 cells, or B1 cells plus CD4⁺ T cells from BALB/c mice. At 2 to 3 months after reconstitution, the recipient's lamina propria, mesenteric lymph node, and spleen cells were isolated, ELISPOT analysis of total and RV-specific IgA production was performed, and the frequencies of IgA ASC and IgSC per 10⁶ cells were determined. The data represent the means ± the SEM for every tested population of cells from each group of mice (three to five mice/group). ASC/IgSC ratios are also shown.