Defective autologous mixed lymphocyte reaction (AMLR) and killer activity generated in the AMLR in cancer patients

Abstract

The autologous mixed lymphocyte reaction (AMLR) and the killer activity generated in the AMLR (AMLR-killer) in the spleen and the peripheral blood of patients with gastric cancer were investigated. The AMLR in cancer patients was suppressed, especially in the spleen, compared to that seen in controls. There was no correlation between AMLR activity and the stage status of the cancer. The cytotoxic activity of AMLR-killer cells against various tumor-cell lines was also suppressed in the spleen, and had a tendency to be suppressed in the peripheral blood of cancer patients. The autologous tumor-killing activity of AMLR-killer cells was developed in cancer patients with high AMLR activity, but was not induced in patients with low AMLR activity. Autotumor killing activity was decreased by the elimination of CD4+ cells, whereas the elimination of CD16+ cells resulted in a marked reduction in cytotoxicity against K562, indicating that the non-specific killer cells which lysed K562 were different from the specific killer cells that lysed autotumor cells. This suggests that AMLR activity is related to the differentiation and proliferation of lymphocytes with specific or non-specific cytotoxic activity and that this activity plays an important role in immune surveillance against tumors.

Dendritic Cells Transduced with Tumor-Associated Antigen Gene Elicit Potent Therapeutic Antitumor Immunity: Comparison with Immunodominant Peptide-Pulsed DCs

“…Spleens were removed 14 days after DC immunization, and then the in vivo primed splenocytes were cocultured (4 × 10 6 /ml) with irradiated (10,000 rad) CT26 cells (4 × 10 5 /ml) in a 6 well-plate in complete medium containing IL-2 at 50 units/ml. After 5 days of coculture, the in vivo restimulated splenocytes were assayed in a 4-hour 51 Cr-release assay as previously described [22, 23]. CT26, Meth-A and Meth-A pulsed with AH-1 (100 µg/2 × 10 6 ) (Meth-A/AH-1) were used as target cells.…”

Bacillus Calmette‐Guérin cell‐wall skeleton enhances the killing activity of cytotoxic lymphocyte‐activated human dendritic cells transduced with the prostate‐specific antigen gene

“…Cytotoxic activity was assayed in a standard 4‐h 51 Cr‐release assay as described previously [16,17]. Briefly, target cells were labelled with Na 2 51 CrO4 at 37 °C for 1 h, washed three times with PBS and then incubated in triplicate with effector cells at various effector : target (E:T) ratios at 37 °C under a 5% CO 2 atmosphere for 4 h in 200 µL of AIM‐V in 96‐well U‐bottom plates.…”

Fibronectin promotes the proliferation of cytotoxic T lymphocytes generated from cancer patients

“…Fresh excised tumour tissues were processed by enzymatic digestion as described previously (Tani et al, 1995;Yamaue et al, 1991;Yamaue et al, 1992;Iwahashi et al, 1992). Briefly, tumour tissues were dissected into pieces smaller than 2 mm3 and these were immersed in medium containing collagenase (2 mg ml-', type V-S; Sigma, St Louis, MO, USA), hyaluronidase (10 U ml-', type IV-S; Sigma) and DNAase-I (0.4 mg ml-'; Sigma).…”