FIG. 7.

Defect in the intracellular processing of full-length NP Traub despite equivalent levels of cytosolic expression of Traub and ARM NP. The top panel shows that whereas transfected full-length ARM NP (pCMV-ARM [see Fig. 5 legend]) is processed correctly as judged by recognition of LCMV-specific CTL over several E/T ratios, there is no recognition of similarly transfected full-length Traub NP (pCMV-Traub). The numbers shown represent the mean value of triplicate samples. Variance was <10% in the 5-h ⁵¹Cr release assay. D7 p^o, day 7 primary immune response; splenic lymphocytes. The lower panels show that cytosolic extracts from the full-length ARM- or Traub-transfected constructs (above) express similar levels of NP by Western blotting and by densitometry analysis. The negative control (U) was processed with cytosolic extract from uninfected BALB cells, and the positive control (I) is from LCMV ARM-infected BALB cells. ARM, pCMV-ARM NP; Traub, pCMV-Traub NP (constructs used to transfect BALB cells). Different concentrations of protein from each sample were loaded, and detection was with monoclonal antibody to LCMV ARM NP (see reference 14 and Materials and Methods).