Alloreactivity and anti-tumor activity segregate within two distinct subsets of cytokine-induced killer (CIK) cells: implications for their infusion across major HLA barriers
Dario Sangiolo
1
2
5
Emanuela Martinuzzi
0
1
Maja Todorovic
1
Katiuscia Vitaggio
1
2
Antonella Vallario
1
Noela Jordaney
5
Fabrizio Carnevale-Schianca
5
Antonio Capaldi
5
Massimo Geuna
0
Laura Casorzo
4
Richard A. Nash
3
Massimo Aglietta
2
5
Alessandro Cignetti
1
0
Laboratory of Clinical and Experimental Cytometry
1
Laboratory of Cancer Immunology
2
Department of Oncological Sciences, University of Torino Medical School
, Torino,
Italy
3
Fred Hutchinson Cancer Research Center and University of Washington Medical School
,
Seattle, WA, USA
4
Unit of Pathology, Institute for Cancer Research and Treatment
, Candiolo, Torino,
Italy
5
Division of Medical Oncology
Donor-derived cytokine-induced killer (CIK) can be infused as adoptive immunotherapy after hematopoietic cell transplant (HCT). Promising results were recently reported in HLA-identical HCT, where mild grafts versus host (GVH) events were observed. To extend this strategy across major HLA barriers (e.g. HLA-haploidentical HCT), further studies on CIK cells' alloreactivity are needed. We hypothesized that alloreactivity and anti-tumor activity of CIK cells segregate within two different cell subsets and could consequently be separated according to CD56 and CD3 expression. We tested CIK cells expanded from seven patients who underwent HCT as treatment of metastatic colorectal cancer. We found that CIK cells maintained their alloreactivity across major HLA barriers when tested as bulk population; after CD56-positive selection, anti-tumor activity was restricted to the CD31/CD561 cell fraction and alloreactivity versus HLA-mismatched PBMC was restricted to the CD31/CD562 cell fraction. Bulk CIK cells from engrafted patients did not exhibit alloreactivity in response to host- or donor-derived PBMC, confirming their low potential for GVH across minor HLA barriers. Moreover, we tested if CIK cells expanded from engrafted patients after HCT were as effective as donor-derived ones and could be considered as an alternative option. The expansion rate and tumor cell killing was comparable to that observed in sibling donors. In conclusion, depletion of CD31/CD562 cells might reduce the risk of GVH without affecting the tumor-killing capacity and could help extending CIK infusions across major HLA barriers. Engrafted patients after HCT could also be considered as an effective alternative option to donor-derived CIK cells.
Introduction
Cytokine-induced killer (CIK) cells are a subset of T
lymphocytes with a NK T cell (NKT) phenotype expressing both the
CD3 and the CD56 markers. CIK cells are mostly CD8+,
express a heterogeneous TCR repertoire, are CD1d
independent and can be reproducibly expanded in vitro from bone
marrow or PBMC over a 3-week time period (14). CIK cells
are capable of a broad MHC-unrestricted anti-tumor activity
against both syngeneic and allogeneic hematological
malignancies, as documented both in vitro and in vivo by murine
models (1, 4, 5).
In pre-clinical studies conducted to date, lymphoma cell
lines and fresh leukemic blasts have been the main tumor
targets (1, 5, 6). Limited data are available on the efficacy
of CIK cells against solid tumors, although efficient killing
842 CIK alloreactivity across major HLA barriers
of hepatocarcinoma by conventional CIK and of ovarian
carcinoma by CIK redirected against the tumor by a
bispecific antibody has been published (79). The mechanism
of tumor killing by CIK cells is perforin mediated but, to
date, it is not completely known which molecules are
involved in tumor recognition (10). An important role is played
by NKG2D homodimer, which mediates the interaction
between CIK cells and tumor targets expressing NKG2D
ligands (11).
Two phase I clinical trials reported the successful ex vivo
expansion and reinfusion of CIK cells from patients with
refractory malignant lymphoma and hepatocellular carcinoma
without any relevant toxicity and with few (3/22) but
significant clinical responses (12, 13).
Allogeneic hematopoietic cell transplantation (HCT) is an
established therapy for hematological malignancies (14)
and more recently studies of HCT after non-myeloablative
conditioning (NMT) have been extended to the field of solid
tumors (1519). Most of the therapeutic effect of NMT
depends on an immune response of allogeneic donor T cells
to recipient malignant cells, referred to as a graft versus
tumor (GVT) effect. NMT has shown to reduce regimen-related
toxicities in comparison with conventional myeloablative
conditioning but graft-versus-host disease (GVHD) and disease
progression remain significant challenges. The beneficial
allogeneic GVT effect may be improved by the infusion of
donor lymphocytes, even if the risk of severe GVHD remains
the major drawback (2023).
In the allogeneic HCT setting, the GVHD potential of CIK
cells was found to be very low in mice models (1, 4, 5). This
makes CIK cells an intriguing alternative to bulk donor
lymphocytes infusion (DLI), especially when donor and recipient
ha (...truncated)