Time (Weeks p.i.) | Infectivity (Days to Death) | | Pathology (G/S) |
|---|
Prn-p
+/+
a
|
Prn-p
+/0
|
Prn-p
+/+
|
Prn-p
+/0
|
|---|
8 | 166 ± 5 | ND | ND | ND |
12 | 158 ± 12 | 174 ± 13 | + +/- | + +/− |
16 | ND | 170 ± 7 | ND | + +/− |
20 | 149 ± 8 | 148 ± 7 | + + +/+ + | + +/+ |
24 | 149 ± 7 | 153 ± 13 | + + +/+ + | + + +/+ |
33 | Dead | 147 ± 5 | Dead | + + + (f)/+ + (f) |
41 | | 151 ± 9 | | + + +/+ + + |
45 | | 157 ± 6 | | + +/+ + |
48 | | 150 ± 9 | | + +/+ + |
50 | | 153 ± 9 | | + + +/+ + |
- Four Prn-p0/+ mice were sacrificed at 12, 16, 20, and 24 weeks after inoculation with mouse RML prions. Their brains were excised, pooled, and 1% (w/v) homogenates were titrated by inoculation into 6 Swiss CD-1 mice (incubation time method). Individual Prn-p0/+ brains recovered between 33 and 50 weeks after inoculation were titrated in the same fashion. The 50-week sample was also titrated by endpoint dilution as described in Experimental Procedures. The titers in Prn-p0/+ brain homogenates analyzed by the incubation time method were calculated by using standard curves that describe linear relationships between survival times of Prn-p+/+ mice and infectious titers for RML prions, as described previously (28); (legend to Table 3). Titers given in the table refer to 10% homogenates. −, no gliosis or spongiosis; +, single reactive astrocytes, no spongiosis; + +, clusters of reactive astrocytes and/or mild spongiosis; + + +, confluent foci of gliosis and/or profound spongiosis; ND, not determined; f, focal; G, gliosis; S, spongiosis.
- aData from (28) for heated samples.
