TABLE 3.
Rat | Dose of P. cariniia | Results
|
||||
---|---|---|---|---|---|---|
No. of cysts per lung | Standard PCRb
|
Quantitative PCR (no. of P. carinii genomes per lung) | ||||
ITS2c | mtrRNAd | UCS-MSG | ||||
255 | 0 | 7 × 105 | Negative | Negative | Negative | <1 × 104 |
256 | 0 | <1 × 104 | Negative | Negative | Negative | <1 × 104 |
257 | 0 | 2 × 106 | Negative | Negative | Negative | <1 × 104 |
260 | 0 | <1 × 104 | Negative | Negative | Negative | <1 × 104 |
261 | 0 | <1 × 104 | Negative | Negative | Negative | <1 × 104 |
262 | 0 | <1 × 104 | Negative | Negative | Negative | <1 × 104 |
267 | 10 | 3 × 107 | Positive | Positive | Positive | 3 × 107 |
268 | 10 | 8 × 108 | Positive | Positive | Positive | 4 × 109 |
269 | 10 | 3 × 105 | ND | ND | Positive | ND |
270 | 10 | 5 × 106 | ND | ND | Negative | ND |
271 | 10 | 2 × 107 | Positive | ND | Positive | 8 × 106 |
272 | 10 | 2 × 108 | Positive | ND | Positive | 3 × 108 |
273 | 10 | 2 × 108 | ND | ND | Positive | ND |
274 | 10 | 1 × 107 | ND | ND | Positive | 7 × 107 |
282 | 104 | 8 × 108 | Positive | Positive | Positive | ND |
283 | 104 | 2 × 108 | Positive | Positive | Positive | ND |
284 | 104 | 6 × 107 | Positive | ND | Positive | ND |
285 | 104 | 1 × 108 | Positive | ND | Positive | ND |
286 | 104 | 3 × 108 | Positive | ND | Positive | ND |
287 | 107 | 5 × 109 | Positive | ND | Positive | ND |
288 | 107 | 2 × 109 | Positive | ND | Positive | ND |
290 | 107 | 3 × 109 | Positive | ND | Positive | ND |
291 | 107 | 6 × 108 | Positive | ND | Positive | ND |
292 | 107 | 6 × 107 | Positive | ND | Positive | ND |
294 | 107 | 6 × 107 | Positive | ND | Positive | ND |
295 | 107 | 3 × 108 | Positive | ND | Positive | ND |
296 | 107 | 9 × 108 | Positive | ND | Positive | ND |
298 | 107 | 2 × 109 | Positive | ND | Positive | ND |
Counts are total number of P. carinii nuclei in 0.200 ml, which was the volume injected into each rat. Nuclei in both cysts and trophic forms of P. carinii were counted with a light microscope.
Standard PCR was performed for 40 rounds under conditions described in Materials and Methods. The primers used are listed in Table 1. ND, not done. The results of a standard PCR were scored as positive if a band of the expected size was visible after an agarose gel was stained with ethidium bromide.
ITS2 is a single-copy locus located in the rRNA gene of P. carinii. The primers used are listed in Table 1.
mtrRNA is the gene in the P. carinii mitochondrial genome encoding the RNA in the large ribosome subunit of mitochondria. The primers used are listed in Table 1.