Table 3.

>Relative Levels of Endogenous Ly49A mRNA Determined from RNase Protection Assays

NK cell sample		Normalized mRNA levels
		β2m−/−				H-2b				H-2d
		LM		Tg No. 2		LM		Tg No. 2		LM		Tg No. 2
Ly49A-end mRNA		100 ± 8		87 ± 16		92 ± 31		80 ± 10		76 ± 13		30 ± 8*
Ly49A-end mRNA  per Ly49A+ cell		100 ± 8		NA		107 ± 36		NA		95 ± 16		NA

Average relative endogenous Ly49A mRNA levels ± SD from three independent experiments. cpm in relevant bands were determined with a phosphorimager. The cpm in the Ly49A band was divided by the cpm of the NKR-P1C control band in the same lane, and these values were normalized to the value obtained with the β2m^−/− littermate preparation (assigned arbitrary value of 100 U). The calculated relative Ly49A mRNA levels per Ly49A⁺ cell are also presented for the nontransgenic samples, determined by normalizing the relative mRNA levels to the average percentage of Ly49A⁺ cells in each nontransgenic LAK cell sample, determined by flow cytometry (25.4% for β2m^−/−, 21.8% for H-2^b, and 20.4% for H-2^d samples). The substantial effect of the Ly49A transgene is indicated in bold. NA, not applicable.  

^‡ P <0.01 versus H-2^d nontransgenic littermate by Student's two-tailed t test.