Adoptive cellular therapy of human breast and colorectal tumor targets using ex vivo activated memory T lymphocytes with potentiation by cis-diamminedichloroplatinum(II)

Effect of contaminating red blood cells on OKT3-mediated polyclonal activation of peripheral blood mononuclear cells

Erythrocytes are typically present as impurities in the majority of peripheral blood mononuclear cell (PBMC) preparations. This study was undertaken to investigate the effects of contaminating red blood cells (RBC) on the ability of OKT3 to activate CD4(+) and CD8(+) T cells. Surprisingly, the levels of gamma interferon, tumor necrosis factor alpha, and interleukin-1 beta (IL-1 beta) produced by PBMC upon stimulation by OKT3 were increased (P < 0.05) in a dose-dependent manner when increasing amounts of autologous RBC (RBC-to-PBMC ratios of 2:1, 10:1, and 50:1) were spiked into PBMC preparations. The OKT3-driven induction of the IL-2 receptor (CD25) and the proliferation of T lymphocytes in response to phorbol myristate acetate were not affected by the addition of RBC.

Ex vivo activated memory T-lymphocytes as adoptive cellular therapy of human renal cell tumour targets with potentiation by cis-diamminedichloroplatinum(II)

OBJECTIVE

To determine if cis-diamminedichloroplatinum(II) (CDDP) enhances, by immunomodulation, ex vivo anti-tumour cytotoxicity of autolymphocyte therapy (ALT) against a chemotherapy-resistant tumour, and if lysis is mediated through T-cells, NK-cells, or both.

MATERIALS AND METHODS

Human renal cell carcinoma (RCC) target cells were derived from surgical specimens and incubated in complete medium (CM) with CDDP, or in CM alone (control group). ALT-cells were prepared from autologous whole peripheral blood mononuclear cells (PBMC) or NK-cell (CD56)-depleted PBMC obtained before surgery. Tumour cells from each group were labelled with chromium-51(51Cr) and used as targets for ALT-cells and PBMC in a standard (4 h) and delayed (18 h) 51Cr-release assay at varying effector/target ratios (E:T).

RESULTS

Tumour cells incubated in CDDP showed enhanced lysis, as measured by the 51Cr-release assay, at all E:T tested. This lysis was significantly greater during the 18 h assay and when ALT-cells were used as the effector cells rather than PBMC. Depletion of CD45RO+ (memory) T-cells from the ALT cell population precluded both the 4 and 18 h tumour cell lysis. Depletion of NK-cells (CD56+) diminished the ex vivo lysis of autologous targets during the 4 but not the 18 h assay. ALT-cells derived from two patients demonstrated ex vivo tumour-specificity against autologous and allogeneic RCC.

CONCLUSIONS

These data suggest that: (i) ex vivo activated memory T-cells are the principal component demonstrating significant tumour-specific cytotoxicity of ALT-cells against RCC tumour targets; (ii) CDDP may alter the physical properties of tumour cells rendering them susceptible to immune-mediated attack; (iii) the combination of ALT and CDDP may lead to increased therapeutic efficacy in patients with metastatic RCC.

Adoptive transfer of ex vivo-activated memory T-cell subsets with cyclophosphamide provides effective tumor-specific chemoimmunotherapy of advanced metastatic murine melanoma and carcinoma

Autolymphocyte therapy (ALT) is adoptive cellular therapy of neoplastic disease using ex vivo activation of autologous (human) or syngeneic (murine) lymphocytes from tumor-bearing hosts (TBH) by low doses of anti-CD3 monoclonal antibody (MAb) and a mixture of previously prepared autologous cytokines (T3CS). Ex vivo activation by T3CS without tumor antigen results in expansion of CD44+ (memory) T cells. These memory T cells (ALT cells) mediate in vivo anti-tumor specificity and with cyclophosphamide (CY) are capable of curing metastatic disease in murine TBH. To determine whether CY could enhance the effectiveness of CD4+ or CD8+ subsets of ALT cells, C57BL/6J TBH with B16 melanoma or Lewis lung (3LL) carcinoma were treated with adoptive chemoimmunotherapy (ACIT) using CD4-depleted or CD8-depleted ALT cells and CY. ALT cells were derived from splenocytes of B16 or 3LL-TBH and activated ex vivo with T3CS. Depletion of CD4+ or CD8+ T cells was performed before or after activation with T3CS. B16-TBH or 3LL-TBH that received ACIT using CY with B16-derived or 3LL-derived CD8-depleted ALT cells, respectively, demonstrated cure of metastatic disease regardless of whether CD8+ T cells were depleted before or after T3CS activation. B16 or 3LL-TBH that received ACIT using CY with B16 or 3LL-derived CD4-depleted ALT cells also cured metastatic disease but only if CD4+ T cells were depleted after T3CS activation. Interleukin (IL)-2 added to pre-T3CS CD4-depleted ALT cells cultured with T3CS restored anti-tumor activity when combined with CY. TBH cured by ACIT using CY and ALT-cell subsets derived from syngeneic TBH with the identical tumor displayed tumor-specific immunity in rejecting a lethal challenge of identical but not reciprocal tumor. TBH given ACIT using CY and ALT-cell subsets derived from splenocytes of syngeneic TBH with reciprocal tumors rejected lethal challenges of both tumors. Tumor specificity measured by interferon (IFN)-gamma and 51Cr-release assays was demonstrated in pre- or post-T3CS/CD8-depleted, post-T3CS/CD4-depleted and pre-T3CS + IL-2/CD4-depleted ALT-cell subsets. Our data demonstrate that ACIT using CY combined with ex vivo T3CS-activated CD44+ memory T-cell subsets conveys long-term tumor-specific immunity.

Ex vivo activated memory T-lymphocytes as adoptive cellular therapy of human soft-tissue sarcoma targets with potentiation by cis-diamminedichloroplatinum(II)

Autolymphocyte therapy (ALT) is tumor-specific, adoptive cellular therapy of neoplastic disease using nonspecific ex vivo activation of autologous peripheral blood lymphocytes (PBL), which are composed primarily of memory T-cells (ALT-cells) and are active in patients with metastatic renal cell carcinoma and melanoma. Ex vivo pretreatment of tumor target cells with certain chemotherapeutic agents can enhance susceptibility to lysis by antitumor lymphocytes. To determine if cis-diamminedichloroplatinum(II) (CDDP) enhances ex vivo antitumor cytotoxicity of ALT-cells and if this lysis is mediated by T- and/or NK-cells and is human leukocyte antigen (HLA)-restricted, human soft tissue sarcoma (STS) target cells were derived from primary and metastatic surgical specimens and were incubated with and without CDDP. ALT-cells were prepared from autologous PBL obtained prior to surgery. Primary (PSTS) and metastatic (MSTS) target cells from each group were labelled with chromium 51 (51Cr) and used as targets for ALT-cells, CD45-depleted ALT-cells, CD56 (NK)-depleted ALT-cells, and PBL in a standard (4-hour) and delayed (18-hour) 51Cr release assay. Interferon-gamma (IFN-gamma) release was measured as an indication of antitumor effect and recognition by the noncytolytic lymphocytes in ALT-cells. Primary tumor target cells incubated in CDDP showed enhanced lysis as measured by the 51Cr release assay compared to non-CDDP-treated controls. Metastatic tumor target cells showed less lysis than the primary targets, although this was enhanced by pretreating metastatic tumor targets with CDDP. Lysis of all tumor targets was significantly greater when ALT-cells were used as the effector cells rather than PBL. Depletion of memory T-cells abrogated ex vivo lysis. Depletion of NK cells (CD56+) affected ex vivo lysis of autologous targets during the 4-hour but not the 18-hour assay. Ex vivo ALT-cell lysis and IFN-gamma release against only the autologous tumor targets confirmed tumor-specificity in one patient. Restriction of ALT-cell lysis and IFN-gamma release against HLA-A2+ autologous and one allogeneic HLA-A2+ STS tumor target, but not other non-STS targets, was demonstrated in another patient. These data suggest that CDDP may help render STS susceptible to tumor-specific, immune-mediated attack and that the combination of ALT and CDDP may lead to effective tumor-specific chemoimmunotherapy in patients with metastatic STS.