TABLE 3.

IFN-γ production by Mtb T-cell lines generated in the presence or absence of CD45R0-positive cells^a

T-cell lines	IFN-γ produced (pg/ml) with the following challenge antigen:
	MIM	H37Ra	rAg85B
Mtb.231	76	122	111
Mtb.231 R0 depleted	42	260	66
Mtb.232	135	747	55
Mtb.232 R0 depleted	140	477	126
Mtb.229	37	98	67
Mtb.229 R0 depleted	260	226	99
Mtb.234b	<10	<10	<10
Mtb.234 R0 depletedb	<10	<10	<10

^aMtb T-cell lines were generated with normal PBMC or with PBMC depleted of CD45R0-positive cells (R0 depleted) and propagated as described in the text. Four weeks later, the cells were challenged in vitro with mycobacterial antigens, and supernatants were tested for IFN-γ production. 

^bThese T-cell lines were specific for mycobacterial antigens, as determined by proliferation (SI, 3 to 13).