TABLE 1.

Effect of dietary protein deprivation on the production of TNF-α in vivo and in vitro in guinea pigs vaccinated with M. tuberculosis H37Ra

Source	Treatment	TNF-α concn (pg/ml)a		P
		HP	LP
Serumb	None	162.2 ± 23.9	395.8 ± 45.3	<0.001
	Intravenous PPD injection	2,409.5 ± 404.6	8,802.5 ± 872.5	<0.001
Macrophagec	PPD	3,188.2 ± 426.6	1,238.8 ± 148.1	<0.01
	H37Rv infection (2 days)	1,322.4 ± 242.8	781.2 ± 182.5	<0.01
	H37Rv infection (4 days)	1,069.5 ± 248.3	502.7 ± 99.6	<0.001

^aMean ± standard error of the mean for four to six guinea pigs per treatment. 

^bSera were separated from M. tuberculosis H37Ra-vaccinated guinea pigs with or without an intravenous injection of 1 mg of PPD/kg of body weight 2 h prior to euthanization. 

^cPeritoneal macrophages were stimulated with PPD at 15 μg/ml for 24 h or infected with M. tuberculosis H37Rv for 2 and 4 days. Cell-free supernatants were collected and measured for TNF-α bioactivity.