Serum Chemokine-release Profiles in AML-patients Might Contribute to Predict the Clinical Course of the Disease.

In cancer or hematologic disorders, chemokines act as growth- or survival factors, regulating hematopoiesis and angiogenesis, determining metastatic spread and controlling leukocyte infiltration into tumors to inhibit antitumor immune responses. The aim was to quantify the release of CXCL8, -9, -10, CCL2, -5, and IL-12 in AML/MDS-pts' serum by cytometric bead array and to correlate data with clinical subtypes and courses. Minimal differences in serum-levels subdivided into various groups (e.g. age groups, FAB-types, blast-proportions, cytogenetic-risk-groups) were seen, but higher release of CXCL8, -9, -10 and lower release of CCL2 and -5 tendentially correlated with more favorable subtypes (<50 years of age, <80% blasts in PB). Comparing different stages of the disease higher CCL5-release in persisting disease and a significantly higher CCL2-release at relapse were found compared to first diagnosis - pointing to a change of 'disease activity' on a chemokine level. Correlations with later on achieved response to immunotherapy and occurrence of GVHD were seen: Higher values of CXCL8, -9, -10 and CCL2 and lower CCL5-values correlated with achieved response to immunotherapy. Predictive cut-off-values were evaluated separating the groups in 'responders' and 'non-responders'. Higher levels of CCL2 and -5 but lower levels of CXCL8, -9, -10 correlated with occurrence of GVHD. We conclude, that in AML-pts' serum higher values of CXCL8, -9, -10 and lower values of CCL5 and in part of CCL2 correlate with more favorable subtypes and improved antitumor'-reactive function. This knowledge can contribute to develop immune-modifying strategies that promote antileukemic adaptive immune responses.

Minor histocompatibility antigen UTY as target for graft-versus-leukemia and graft-versus-haematopoiesis in the canine model.

Male patients with female-stem-cell donors have better prognosis compared to female-to-male combinations due to Y-encoded minor histocompatibility antigens recognized by female-alloimmune-effector lymphocytes in the context of a graft-versus-leukemia (GvL) effect. We provide data in a dog-model that the minor histocompatibility antigen UTY might be a promising target to further improve GvL-immune reactions after allogeneic-stem-cell transplantations. Female-canine-UTY-specific T cells (CTLs) were stimulated in vitro using autologous-DCs loaded with three HLA-A2-restricted-UTY-derived peptides (3-fold-expansion), and specific T cell responses were determined in 3/6 female dogs. CTLs specifically recognized/lysed autologous-female-peptide-loaded DCs, but not naïve-autologous-female DCs and monocytes. They mainly recognized bone-marrow (BM) and to a lower extent DCs, monocytes, PBMCs and B-cells from DLA-identical-male littermates and peptide-loaded T2-cells in an MHC-I-restricted manner. A UTY-/male-specific reactivity was also obtained in vivo after stimulation of a female dog with DLA-identical-male PBMCs. In summary, we demonstrated natural UTY processing and presentation in dogs. We showed that female-dog CTLs were specifically stimulated by HLA-A2-restricted-UTY peptides, thereby enabling recognition of DLA-identical-male cells, mainly BM cells. These observations suggest UTY as a promising candidate-antigen to improve GvL-reactions in the course of immunotherapy.

Conversion of AML-blasts to leukemia-derived dendritic cells (DCleu) in 'DC-culture-media' shifts correlations of released chemokines with antileukemic T-cell reactions.

Dendritic cells (DC) and T-cells are mediators of CTL-responses. Autologous (from patients with acute myeloid leukaemia (AML) or myelodysplasia (MDS)) or allogeneic (donor)-T-cells stimulated by DCleu, gain an efficient lysis of naive blasts, although not in every case. CXCL8, -9, -10, CCL2, -5 and Interleukin (IL-12) were quantified by Cytometric Bead Array (CBA) in supernatants from 5 DC-generating methods and correlated with AML-/MDS-patients' serum-values, DC-/T-cell-interactions/antileukemic T-cell-reactions after mixed lymphocyte culture (MLC) and patients' clinical course. The blast-lytic activity of T-cells stimulated with DC or mononuclear cells (MNC) was quantified in a cytotoxicity assay. Despite great variations of chemokine-levels, correlations with post-stimulation (after stimulating T-cells with DC in MLC) improved antileukemic T-cell activity were seen: higher released chemokine-values correlated with improved T-cells' antileukemic activity (compared to stimulation with blast-containing MNC) - whereas with respect to the corresponding serum values higher CXCL8-, -9-, and -10- but lower CCL5- and -2-release correlated with improved antileukemic activity of DC-stimulated (vs. blast-stimulated) T-cells. In DC-culture supernatants higher chemokine-values correlated with post-stimulation improved antileukemic T-cell reactivity, whereas higher serum-values of CXCL8, -9, and -10 but lower serum-values of CCL5 and -2 correlated with post-stimulation improved antileukemic T-cell-reactivity. In a context of 'DC'-stimulation (vs serum) this might point to a change of (CCL5 and -2-associated) functionality from a more 'inflammatory' or 'tumor-promoting' to a more 'antitumor'-reactive functionality. This knowledge could contribute to develop immune-modifying strategies that promote antileukemic (adaptive) immune-responses.

Acute myeloid leukemia (AML) can be oligoclonal.

Acute myeloid leukemia (AML) is usually thought to represent a monoclonal disease. Among 45 cases of newly diagnosed AML we found rearranged bands in 14 cases using the Southern blot methodology and immunoglobulin (Ig) joining region (JH) or T-cell receptor (TCR beta) probes. In three patients, the findings indicated an oligoclonal disease. One case was characterized by several bands in the JH blot, some of which reappeared at different time points during remission. A second case had monoclonally rearranged Ig-JH sequences in the bone marrow but exclusively germline configuration in DNA from peripheral blood cells despite the presence of 84% blasts. A third case was characterized by two different, Ig-JH and c mu gene rearranged cell populations at diagnosis but relapsed with a germline pattern without reappearance of the previous clones. These data indicate that AML may differentiate along different lineages with predominant appearance of one or the other subclone in the course of the disease.

Clonality analysis as a tool to study the biology and response to therapy in myelodysplastic syndromes.

We examined the bone marrow of 45 patients with MDS at the time of diagnosis and in the course of the disease by means of Southern blot analysis and cytogenetic studies to detect and evaluate clonal markers and their implication on the prognosis of the disease and the response to treatment. All patients were enrolled in an EORTC study and received low-dose Ara-C with or without growth factors according to the study protocol. Thirty patients (67%) were characterized by different clonal markers, such as various gene rearrangements (eg Ig-JH, tcR-beta, bcr, GM-CSF, G-CSF or IL-3) and/or chromosomal markers at the time of diagnosis or early in the course of the disease. In 23 of 30 cases that could be studied in the course of the disease, a statement about the clonal situation was possible: in three cases (8%) the clonal situation did not change, in nine cases (39%) at least a transient reduction of clonal cells could be demonstrated, suggesting partial or complete response to therapy. In eight cases (35%) a change for the worse could be seen. In four cases (17%) involvement of multiple clones could be demonstrated with the clones exhibiting different susceptibilities to treatment. Clinical evaluation showed that patients without clonal markers at diagnosis had a better prognosis as compared to patients who presented with clonal markers. We suggest that clonality analysis at diagnosis and in the course of the disease will be a useful tool to study the biology and response to treatment in MDS.

Immunological classification of chronic myeloid leukemia distinguishes chronic phase, imminent blastic transformation, and acute lymphoblastic leukemia.

The clinical course of chronic myeloid leukemia (CML) is highly variable and therefore it is difficult to predict the duration of the chronic phase. We studied the immunological expression of maturation patterns in 62 cases of CML (30 cases in clinical/cytological blast crisis (BC), 32 cases in clinical/cytological chronic phase (CP) by means of a double marker enzyme immuno assay (DM-EIA). Immunological findings were supplemented by Southern blots using Ig-JH-, TCRbeta- and bcr-probes. Patients in BC (n = 30) expressed high proportions of CD10, CD20, CD33, CD34 and low degrees of a mature myeloid marker (CD15). Myeloid BC bone marrow (BM) cells showed a high degree of coexpression of unusual, lineage restricted markers: 25% of CD15-positive cells also expressed markers like CD10, CD20 or CD34. In contrast, BM cells in lymphoid BC did not show this coexpression. In CP two groups were distinguished immunologically: concordant cases which were immunologically normal (n = 14) and discordant cases (n = 18) which showed increased proportions of unusual, lineage restricted markers and double labelled cells (e.g. CD15/CD34). The latter group developed clinical BC earlier during further follow up (p = 0.009). Cases of lymphoid BC (n = 11)--in contrast to acute lymphoblastic leukemia (ALL) patients (n = 21)--did not show coexpression of CD15/CD10, CD20, CD34. These data show that blast clones can be detected in CML-CP by characteristic immunological maturation defects several months before the clinical onset of BC. Moreover, the lymphoid "blasts" of CML-BC represent a relatively differentiated lymphoid population of cells which can be distinguished from ALL by their lack of coexpression of unusual, lineage restricted markers.

Development of myeloma and secondary myelodysplastic syndrome from a common clone.

We report the case of a 49-year-old woman who presented with a monoclonally IgG kappa expressing myeloma since October 1989. Four years later, after 24 cycles of Melphalan-containing chemotherapy, bone marrow (BM) cells of the patient cytologically revealed myelodysplastic changes for the first time. Cytogenetic examination of the BM obtained in January 1994 showed two clonally aberrant main lines. Each of them represented one of the hematological neoplastic diseases. The quantitatively major clone (MDS-clone) showed a deletion of the long arm of chromosome 7, typical for secondary myeloid disorders. The other clone (myeloma (MM) clone) was characterized by a reciprocal translocation between the short arm of chromosome 8, band q24, a region known to contain the c-myc gene, and the long arm of chromosome 2, band p12, where the Ig kappa gene is located. An unusual finding, however, was that an abnormality of the long arm of chromosome 16 could be detected in both obviously unrelated clones. In the further course of the disease, the MDS and MM clones could be detected, both of them showing cytogenetically a clonal evolution characterized by additional clonal abnormalities. Our data stress the significance of cytogenetics in detecting typical clonal abnormalities in different malignant hematological disorders and in detecting "clonal evolution" as an indicator of the progress of the disease. Moreover, our data suggest that MM and MDS may arise from a common stem cell, which may be characterized by a clonal cytogenetic abnormality.

Chronic myeloid leukemia associated hypereosinophilic syndrome with a clonal t(4;7)(q11;q32).

Patients with chronic myeloid leukemia (CML) show the Philadelphia (Ph) translocation in more than 95% of the cases. The remaining cases, without the cytogenetic or molecular equivalent of the BCR-ABL rearrangement, are "Philadelphia negative" and may have alternate chromosomal aberrations. Ph negative CML patients are known to have a poor prognosis. We report on a young patient with a hypereosinophilic syndrome in the presence of a clonal translocation t(4;7) with a peripheral leukocytosis, a severe thrombocytopenia, and anemia at first presentation, who developed bone marrow changes typical of CML. Bone marrow function and hypereosinophilia improved only partially and temporarily under therapy. The patient died 10 months after diagnosis of diffuse leukemic embolism and organ infiltration resulting in paraplegia. The case demonstrates that beside "idiopathic" hypereosinophilic syndromes (HES), a proportion of such patients suffer from eosinophilic leukemias. In these cases, karyotype analysis may help to distinguish these states by the identification of clonal chromosomal abnormalities. A karyotype anomaly hitherto not reported can be added to the list of aberrations in hypereosinophilic states associated with myeloproliferative processes.