Incidence of Tumor Growth and Tumor Regression in Athymic Mice Injected With BL Cells
| Cell Line . | EBV Status-150 . | Tumors/ Mice Injected . | Days to Tumor Appearance-151 . | Days to Tumor Regression-152 . | Regressing Tumors . | % Regression . | Maximum Size (cm2)-153 . |
|---|---|---|---|---|---|---|---|
| PA682 BM2 | + | 9/10-155 | 28 ± 9.5 | 52 ± 9.2 | 8/8 | 100 | 4.5 ± 2.2 |
| PA682 PB | + | 9/9-155 | 19 ± 6.2 | 19 ± 16 | 6/7 | 86 | 2.1 ± 2.1 |
| PA682 PE2 | + | 8/10-155 | 7.1 ± 0.9 | 28 ± 17 | 7/7 | 100 | 1.4 ± 1.1 |
| JLP EBV+ | + | 5/14 | 11 ± 3.3 | 46 ± 15 | 5/5 | 100 | 1.8 ± 1.4 |
| KK124 | + | 8/12 | 16 ± 9.1 | 32 ± 13 | 4/8 | 50 | 2.0 ± 1.0 |
| Raji | + | 5/5 | 21 ± 0.0 | 77 ± 43 | 3/5 | 60 | 5.1 ± 3.0 |
| Namalwa | + | 14/16 | 14 ± 6.0 | 55 | 1/14 | 7.1 | 6.8 |
| Daudi | + | 7/7 | 8.6 ± 5.0 | — | 0/7 | 0 | — |
| ST488 | − | 3/9 | 38 ± 8.1 | — | 0/3 | 0 | — |
| Louckes | − | 6/11 | 65 ± 26 | 113 | 1/6 | 17 | 9.5 |
| BL41 | − | 15/16 | 41 ± 34 | — | 0/15 | 0 | — |
| Ramos | − | 3/4 | 29 ± 0.0 | — | 0/3 | 0 | — |
| CA46 | − | 12/15 | 11 ± 6.7 | — | 0/12 | 0 | — |
| BL30 | − | 10/10 | 18 ± 6.3 | — | 0/10 | 0 | — |
| BML 895 | − | 3/10 | 62 ± 0.0 | 75 ± 44 | 2/3 | 66 | 3.6 ± 1.3 |
| JD38PB | − | 8/8 | 13 ± 6.4 | — | 0/8 | 0 | — |
| JD38BM | − | 6/10 | 35 ± 14 | — | 0/6 | 0 | — |
| Cell Line . | EBV Status-150 . | Tumors/ Mice Injected . | Days to Tumor Appearance-151 . | Days to Tumor Regression-152 . | Regressing Tumors . | % Regression . | Maximum Size (cm2)-153 . |
|---|---|---|---|---|---|---|---|
| PA682 BM2 | + | 9/10-155 | 28 ± 9.5 | 52 ± 9.2 | 8/8 | 100 | 4.5 ± 2.2 |
| PA682 PB | + | 9/9-155 | 19 ± 6.2 | 19 ± 16 | 6/7 | 86 | 2.1 ± 2.1 |
| PA682 PE2 | + | 8/10-155 | 7.1 ± 0.9 | 28 ± 17 | 7/7 | 100 | 1.4 ± 1.1 |
| JLP EBV+ | + | 5/14 | 11 ± 3.3 | 46 ± 15 | 5/5 | 100 | 1.8 ± 1.4 |
| KK124 | + | 8/12 | 16 ± 9.1 | 32 ± 13 | 4/8 | 50 | 2.0 ± 1.0 |
| Raji | + | 5/5 | 21 ± 0.0 | 77 ± 43 | 3/5 | 60 | 5.1 ± 3.0 |
| Namalwa | + | 14/16 | 14 ± 6.0 | 55 | 1/14 | 7.1 | 6.8 |
| Daudi | + | 7/7 | 8.6 ± 5.0 | — | 0/7 | 0 | — |
| ST488 | − | 3/9 | 38 ± 8.1 | — | 0/3 | 0 | — |
| Louckes | − | 6/11 | 65 ± 26 | 113 | 1/6 | 17 | 9.5 |
| BL41 | − | 15/16 | 41 ± 34 | — | 0/15 | 0 | — |
| Ramos | − | 3/4 | 29 ± 0.0 | — | 0/3 | 0 | — |
| CA46 | − | 12/15 | 11 ± 6.7 | — | 0/12 | 0 | — |
| BL30 | − | 10/10 | 18 ± 6.3 | — | 0/10 | 0 | — |
| BML 895 | − | 3/10 | 62 ± 0.0 | 75 ± 44 | 2/3 | 66 | 3.6 ± 1.3 |
| JD38PB | − | 8/8 | 13 ± 6.4 | — | 0/8 | 0 | — |
| JD38BM | − | 6/10 | 35 ± 14 | — | 0/6 | 0 | — |
Six- to eight-week-old female BALB/c nu/nu mice maintained in pathogen-limited conditions were exposed (total body) to 4 Gy gamma irradiation, and 24 hours later injected subcutaneously with 1 × 107 viable cells from the indicated exponentially growing BL cell lines. Animals were observed weekly for at least 140 days, and tumor size estimated in square centimeters as the product of two-dimensional caliper measurements (longest perpendicular length and width). A tumor was defined as a mass measuring at least 0.25 cm2 in surface area increasing in size for at least 2 subsequent weeks. Tumors were considered in regression either when three consecutive tumor measurements separated by 1 week showed a size reduction of at least 20% or when, in the absence of measurable size increase, tumor tissue necrosis and/or fibrosis involved greater than 25% of tumor tissue sections through the maximum diameter.
EBV status was determined by RT-PCR for EBNA1.
Calculated from the day of cell line injection; expressed as mean (±SD) for the group.
Days to tumor regression were calculated from the day of tumor appearance to the first day regression was observed.
Maximum tumor size was calculated only for tumors that underwent regression, and is expressed as mean (±SD) for the group. Progressively growing tumors were greater than 7.0 cm2 in size before mice were killed.
Four mice from these groups were killed for in vitro studies before regression could be evaluated.