E. van de Wiel-van Kemenade

Quantification of donor and recipient hemopoietic cells by real-time PCR of single nucleotide polymorphisms

Quantification of donor and recipient hemopoietic cells by real-time PCR of single nucleotide polymorphisms

Induction of graft-versus-leukemia to prevent relapse after partially lymphocyte-depleted allogeneic bone marrow transplantation by pre-emptive donor leukocyte infusions

In this prospective study we analyzed pre-emptive donor leukocyte infusions (DLI) in 82 consecutive patients transplanted with partially T cell-depleted grafts for acute myeloid leukemia, acute lymphoid leukemia, chronic myeloid leukemia, refractory anemia with excess of blasts, refractory anemia with excess of blasts in transformation and multiple myeloma. Donors were HLA-identical siblings. Patients without significant acute (>grade 1) and/or chronic GVHD were scheduled to be treated with DLI (35 patients) and 31 actually received DLI. Patients who developed acute GVHD >grade 1 and/or chronic GVHD were not scheduled to receive DLI and served as a comparison group (47 patients). The median interval between BMT and DLI was 22 weeks. The first six patients received 0.7 × 108 CD3+cells/kg body weight (b.w.). Five out of these six patients developed acute GVHD (grade 1: n = 2, grade 3: n = 2 and grade 4: n = 1) which was more frequent and more severe than we had anticipated. In the next 25 patients the number of T lymphocytes was diminished to 0.1 × 108 CD3+ cells/kg b.w. which resulted in less frequent and less severe GVHD. Eight patients in this group developed acute GVHD (grade 1: n = 4, grade 2: n = 4) and three patients had limited chronic GVHD. Patients in the DLI group needed more time to establish complete donor chimerism confirmed by a higher number of mixed chimeras at 6 months after BMT. The projected 3-year probability of disease-free survival was 77% for the 35 patients intended to treat with DLI and 45% for the patients of the comparison group (P = 0.024). Relapse rate at 36 months after transplantation was 18% in the patients who were intended to treat with DLI and 44% in the comparison group (P = 0.026). We conclude that pre-emptive DLI is feasible and generates favorable relapse rates in patients who are at high risk for relapse. Furthermore, the incidence and severity of GVHD disease after DLI is dependent on the number of CD3+ cells infused.

TCR gamma delta cytotoxic T lymphocytes expressing the killer cell-inhibitory receptor p58.2 (CD158b) selectively lyse acute myeloid leukemia cells.

Cytotoxic T lymphocytes (CTL) are thought to play an important role in the graft-versus-leukemia (GVL) response. Unfortunately, GVL reactivity is often associated with life-threatening graft-versus-host disease (GVHD). Characterization of CTL that selectively attack leukemic cells but not normal cells may lead to the development of adjuvant immunotherapy that separates GVL from GVHD. Here, we describe TCRγδ (Vγ9/Vδ1) CTL, isolated from the peripheral blood of an AML patient after stem cell transplantation (SCT), that very efficiently lysed freshly isolated acute myeloid leukemia (AML) cells and AML cell lines. Interestingly, HLA-matched non-malignant hematopoietic cells were not killed. We revealed that the killer cell-inhibitory receptor (KIR) p58.2 (CD158b) specific for group 2 HLA-C molecules negatively regulates the cytotoxic effector function displayed by these TCRγδ CTL. First, an antibody against HLA-C enhances lysis of non-malignant cells. Secondly, stable transfection of HLA-Cw*0304 into the class I-negative cell line 721.221 inhibited lysis. Finally, engagement of p58.2 by antibodies immobilized on FcγR-expressing murine P815 cells inhibits CD3- and TCRγδ-directed lysis. Compared to non-malignant hematopoietic cells, AML cells express much lower levels of MHC class I molecules making them susceptible to lysis by p58.2+ TCRγδ CTL. Such KIR-regulated CTL reactivity may have a role in the GVL response without affecting normal tissues of the host and leading to GVHD. Bone Marrow Transplantation (2001) 27, 1087–1093.

Activation and expansion of tumour-infiltrating lymphocytes by anti-CD3 and anti-CD28 monoclonal antibodies

SummaryCytotoxic T lymphocytes from healthy donors can be expanded to high numbers from the peripheral blood using combinations of anti-CD3 and anti-CD28 monoclonal antibodies (mAb). We investigated whether these antibodies could also be used to induce outgrowth of tumour-infiltrating lymphocytes (TIL) from tumour tissue. In the initiation phase of TIL culture immobilized anti-CD3 antibodies together with anti-CD28 mAb and low-dose interleukin-2 induced a rapid expansion of T cells from various human tumour tissues. The cultured cells showed high levels of cytotoxic T lymphocyte activity, but low levels of lymphokine-activated killer cell activity were generated. This study shows that TIL can be efficiently expanded from tumour tissue by combinations of anti-CD3 and anti-CD28 antibodies. This protocol for cell expansion in vitro may substantially reduce the time required to reach sufficient numbers of TIL for re-infusion to the patient.

In Relapsed Patients after Lymphocyte Depleted Bone Marrow Transplantation the Percentage of Donor T Lymphocytes Correlates Well with the Outcome of Donor Leukocyte Infusion

Donor leukocyte infusions (DLI) from the original marrow donor have been shown to induce remission in patients with relapse after BMT. We analyzed factors that were associated with remission. Twenty-six patients with a relapse after T cell depleted BMT received DLI. The following pre-DLI factors were analyzed: sex and age of the patients and donors, GVHD after BMT, indication for DLI, percentage of donor T lymphocytes in the patient at the time of DLI, interval between relapse and DLI, and number of T lymphocytes infused. Remission was achieved in 11 of 15 patients (73%) treated for relapsed CML and in one of 11 patients (9%) treated for relapsed AML, ALL or RAEB-t (P = .002). Two of 13 patients (15%) with < or =40% of T lymphocytes from donor origin attained remission compared with 10 of 13 patients (77%) with >40% (P = .002). Two of 13 patients (15%) with an interval of < or =18 months between BMT and first DLI entered remission compared with 10 of 13 patients (77%) with an interval of >18 months (P = .002). Multivariate analysis demonstrated that indication for DLI (CML versus AML/ALL and RAEB-t) and the percentage T lymphocytes from donor origin (< or =40 versus >40) were significantly correlated with remission (P = .03). The occurrence of GVHD post DLI was highly associated with achievement of remission (P = .0001). DLI res ults in remission in a high percentage of patients with relapsed CML after BMT. The percentage of T lymphocytes from donor origin still present in the patient at the time of DLI is highly correlated with achievement of remission.

Dynamics in chimerism of T cells and dendritic cells in relapsed CML patients and the influence on the induction of alloreactivity following donor lymphocyte infusion

Donor lymphocyte infusion (DLI) after allogeneic SCT induces complete remissions in approximately 80% of patients with relapsed CML in chronic phase, but some patients do not respond to DLI. We studied absolute numbers of dendritic cell (DC) subsets and chimerism in T cells and two subsets of blood DCs (myeloid DCs (MDCs) and plasmacytoid DCs (PDCs)) in relation to DLI-induced alloreactivity. Based on T cell and DC chimerism, we identified three groups. Four patients were completely donor chimeric in T cells and DC subsets. These patients had an early stage of relapse, and three of the four patients attained complete molecular remission (CMolR) without significant GVHD. Six patients were completely donor in T cells and mixed chimeric in DC subsets. All patients entered CMolR, but this was associated with GVHD in four and cytopenia in three patients. Five patients had mixed chimerism in T cells and complete recipient chimerism in MDC; only two patients entered CMolR. Our data suggest that the combination of donor T cells and mixed chimerism in DC subsets induces a potent graft-versus-leukemia (GVL) effect in association with GVHD. DLI in patients with an early relapse and donor chimerism in both T cells and DC subsets results in GVL reactivity without GVHD.

Biodistribution and retention time of retrovirally labeled T lymphocytes in mice is strongly influenced by the culture period before infusion.

T lymphocytes used for adoptive immunotherapy are often cultured before transfer to generate sufficient amounts of effector cells with desired specificity. Modification of lymphocytes induced by in vitro activation and expansion may influence their potential effector capacity by altering the survival and trafficking patterns after transfer. In this report, the authors show that the culture period of T cells after ConA/IL-2 stimulation strongly influences the retention and tissue distribution of these cells after infusion into syngeneic C57BL/6 mice. Infused labeled cells that have been cultured for 3 days remained in the peripheral blood and organs in at least a ten-fold higher number than cells cultured for 8 days. In addition, cells cultured for 3 days preferentially migrate to lungs and liver shortly after infusion and subsequently to lymph nodes and spleen. Cells cultured for 8 days preferentially migrate to liver and can be hardly detected in lymph nodes. In contrast, labeled cells cultured for 3 days are predominantly present in lymph nodes starting from day 8 until day 28. We showed that accurate monitoring of transferred cells is feasible, which may contribute to understanding response to adoptive immunotherapy.

Possible role for cytotoxic lymphocytes in the pathogenesis of acute interstitial nephritis after recombinant interleukin-2 treatment for renal cell cancer

A patient with renal cell cancer developed acute renal failure due to biopsy-proven acute tubulo-interstitial nephritis (AIN) in the 6th week of continuous infusion of 9 × 106 IU m−2 day−1 recombinant interleukin-2 (rIL-2). We investigated whether the AIN was the result of a cellular cytotoxic reaction induced by the rIL-2 treatment. The cytolytic activity of cryopreserved peripheral blood lymphocytes (PBL), isolated before and at the end of the rIL-2 treatment (at the time of AIN), was studied after 5 days of culture with or without rIL-2 or anti-CD28 and immobilized anti-CD3 antibodies. The PBL isolated before and at the end of the rIL-2 treatment showed cytolytic activity towards a number of allogeneic targets. However, only the PBL isolated at the end of the rIL-2 treatment showed, when stimulated with rIL-2 in vitro, significant cytolytic activity against an autologous renal cell line cultured from the AIN biopsy specimen and against an allogeneic renal cell cancer cell line. These PBL displayed no enhanced killing capacity towards autologous PBL and the melanoma cell line M14. These observations suggest that the AIN may be the result of a cytotoxic lymphocyte-mediated reaction induced by the rIL-2 treatment.

Cell surface associated mucins: Structure and effects on cell adhesion

Cell surface associated mucins are a class of transmembrane glycoproteins that protrude high above the cell surface and can mask other cell surface molecules, thereby interfering with the function of the latter molecules. In particular, adhesion molecules are affected, which has important consequences for cellular processes that are dependent on adhesion such as cytolysis by immune cells and probably also invasion and metastasis. Episialin is such a cell-associated mucin which is highly overexpressed on certain carcinomas and it can serve as a prototypic cell associated mucin. Here, we discuss its structure, its effect on cellular adhesionin vitro andin vivo and the consequences for LAK cell and CTL mediated cytolysis. In addition, we discuss the biological impact of other related molecules.