Table 1.

Clusters of Saf32 immunogold labeling are prion disease-related.

Sample source	Gold particles in clusters (n)	Clusters (n)
65 dpi	122	22
85 dpi (20 μm)	130	24
BH	8	2
KO	5	1
65 dpi	40	8
85 dpi	89	20
99 dpi	141	27
KO	4	1
99 dpi	103	21
BH	8	2
KO	0	0

Samples were obtained from FVB mice inoculated with RML prions at the indicated days postinoculation (dpi), and from PrP-knockout (KO) mice and FVB mice (BH) inoculated with normal brain homogenate at 116 dpi. Numbers of clusters of Saf32 labeling and the total number of gold particles in clusters were counted in a 30-μm–wide strip of stratum oriens. The results are grouped according to the batches of primary and secondary antibody used. Clusters of gold labeling were often found in infected brains with only small numbers of clusters observed in control hippocampal sections (BH and KO). Within experiments, the numbers of clusters per brain increased with disease incubation time. All labeling experiments involved different animals.