Table 3. Expression of mRNA for proteins involved in cytotoxicity in subtypes of intraepithelial and lamina propria T lymphocytes of human jejunum.
| Cytotoxic protein* | ||||||
|---|---|---|---|---|---|---|
| T-cell subtype† | Source of T-cell subtype | Perforin‡ | GrB‡ | FasL‡ | TNF-α‡ | TRAIL‡ |
| CD4+ | Epithelium | 1/5 | 1/4 | 1/4 | 3/3 | 3/5 |
| Lamina propria | 3/7 | 0/4 | 2/7 | 6/7 | 5/7 | |
| CD8+ | Epithelium | 3/4 | 5/5§ | 4/4 | 3/3 | 3/4 |
| Lamina propria | 7/7 | 7/7§§ | 5/7 | 7/7 | 7/7 | |
| CR-γδ+ | Epithelium | 2/3 | 2/3 | 3/3 | 2/3 | 2/3 |
| Lamina propria | 3/3 | 0/1 | 2/3 | 2/3 | 2/3 | |
*
mRNA for the indicated protein was determined by RT-PCR. Samples were titrated to give equal signals for β-actin mRNA. mRNA for CD45 was detected in all samples.
†
CD4+, CD8+ and TCR-γδ+ cells were retrieved by treatment of freshly isolated intraepithelial and lamina propria lymphocytes with anti-CD4, anti-CD8 or anti-TCR-γδ mAb-coated magnetic beads.
‡
Results are expressed as number of positive samples/number of samples analysed.
§
P<0·05 and
§§
P=0·01. P-values obtained in statistical analyses using two-tailed Fisher's exact test comparing the frequencies of CD4+ and CD8+ samples from the corresponding source expressing the same mRNA species.