A phase 2, randomized, double-blind, multicenter study comparing siltuximab plus best supportive care (BSC) with placebo plus BSC in anemic patients with International Prognostic Scoring System low- or intermediate-1-risk myelodysplastic syndrome.

Interleukin-6 (IL-6) may play an important role in the pathophysiology of anemia of inflammation associated with myelodysplastic syndrome (MDS). This double-blind, placebo-controlled, phase 2 study assessed the efficacy and safety of siltuximab, a chimeric anti-IL-6 monoclonal antibody, in patients with low- and intermediate-1-risk MDS who require transfusions for MDS anemia. Patients were randomized in a 2:1 ratio to siltuximab 15 mg kg(-1) every 4 weeks + best supportive care (BSC) or placebo + BSC for 12 weeks. The primary endpoint was reduction in red blood cell (RBC) transfusions to treat MDS anemia, defined as ≥50% relative decrease and ≥2-unit absolute decrease in RBC transfusions. Fifty and 26 patients were randomized to the siltuximab and placebo groups, respectively. The study did not meet its prespecified hypothesis, with six (12%) patients in the siltuximab group and one (3.8%) in the placebo group having reductions in RBC transfusions (P = 0.271). At the time of the planned futility analysis, the prespecified cutoff criteria were not met, and the study was terminated early due to lack of efficacy. No unexpected safety findings were observed. In conclusion, compared to placebo, treatment with siltuximab did not reduce RBC transfusions in transfusion-dependent patients with low- and intermediate-1-risk MDS. Future studies might explore siltuximab in patients with less iron overload and with elevated IL-6 levels and/or using higher doses for MDS.

RARS with fibrosis and del(20q) transformed into ALL.

Transformation of myelodysplastic syndrome (MDS) into acute myelogenous leukemia occurs in approximately 30 % of cases, while progression into acute lymphoblastic leukemia (ALL) is rare. We report on a 67-year-old man with the diagnosis of MDS, subtype refractory anemia with ring sideroblasts (RARS), karyotype 20q- , JAK-2 negative and grade III fibrosis on the bone marrow biopsy, who evolved into ALL 33 months after the diagnosis of MDS. RARS is one of the subtypes of MDS with most indolent course. Deletion of the long arm of chromosome 20 (20q-) is considered as good prognosis by the International Prognostic Scoring System, an important scoring system for predicting survival and evolution of MDS. Primary MDS with bone marrow fibrosis may represent a distinct clinicopathological and is supposed to have an unfavorable prognosis. The combined analysis of these features makes this rare report still more challenging and illustrates that biology of MDS is yet to be discovered.

Apoptotic cells and clonally expanded cytotoxic T cells in bone marrow trephines of patients with myelodysplastic syndrome.

AIMS: There is increasing evidence that autoimmunity is involved in the pathogenesis of myelodysplastic syndromes (MDS). We examined the number of apoptotic cells, and analysed the T cells and the T cell receptor gene rearrangements in bone marrow trephines of patients with low-grade MDS [refractory anaemia (RA), refractory anaemia with ringed sideroblasts (RAS) and refractory cytopenia with multilineage dysplasia (RCMD)] to investigate the correlation between T cells and apoptosis. METHODS AND RESULTS: Bone marrow trephines from 30 patients with RA, seven patients with RCMD, four patients with RAS and 11 normal bone marrow donors were stained for CD3 and for apoptotic cells using immunohistochemistry and terminal deoxynucleotidyl transferase 2'-deoxyuridine, 5'-triphosphate (dUTP) nick end labelling (TUNEL) technique, respectively. The positive cells were quantified by computer-assisted image analysis. In addition, CD 8 and T cell-restricted intracellular antigen-1 (TIA-1)-positive cells were analysed by single staining and evaluated semiquantitatively by light microscopy. Junctional diversity of the T cell receptor (TCR) α-, ß- and γ-chains were analysed in 24 cases of RA and RCMD by reverse transcription-polymerase chain reaction (RT-PCR). In all cases of RA, RCMD and RAS an increase of apoptotic cells was accompanied by an increase of T cells, when compared to normal donors (P < 0.001). Expression of TIA-1 was found in 33 of 41 patients with low-grade MDS. In contrast, normal controls showed either no or only very weak expression. Furthermore, 14 of 24 cases with low-grade MDS showed clonal TCR gene rearrangement. CONCLUSION: These findings provide evidence that increased apoptosis in low-grade MDS correlates with increased numbers of cytotoxic T cells. A considerable proportion of the MDS cases showed clonal TCR rearrangement suggesting an antigen-driven selection of the T cells. We therefore speculate that cases of MDS can be accompanied by a presumably autoreactive T cell-mediated apoptosis induction in bone marrow cells.

Recipient-derived HPA-1a antibodies: a cause of prolonged thrombocytopenia after unrelated donor stem cell transplantation.

BACKGROUND: Patients with human platelet antigen (HPA) specific antibodies in cases of neonatal alloimmune thrombocytopenia and platelet (PLT) refractoriness derive clinical benefit from the use of HPA-selected PLTs. STUDY DESIGN AND METHODS: This study describes three patients with underlying diagnoses of acute myeloid leukemia, chronic lymphocytic leukemia, and myelodysplasia, respectively, who underwent allogeneic bone marrow transplantation (BMT) with unrelated donors matched at the HLA-A, B, C, Dr, and DQ loci but who failed to achieve an adequate PLT count. Investigation using PLT immunofluorescence test, monoclonal antibody immobilization of PLT antigens assay, and genotyping revealed the presence of recipient-derived HPA-1a antibodies. RESULTS: In two patients, anti-HPA-1a was detected post-BMT and in the third patient, anti-HPA-1a was detected during pre-BMT chemotherapy. Despite apparent 100% engraftment of donor cells, the patients' PLT counts failed to recover 9-10 months posttransplant. The patients remained PLT-transfusion dependent and failed to achieve satisfactory increments following random donor or HLA-matched PLT transfusions. After the identification of HPA-1a antibodies, the patients were supported by HPA-1a(-) PLTs and satisfactory posttransfusion PLT increments were obtained. These cases illustrate that HPA-1a antibodies may remain detectable for 10 months following apparently successful donor engraftment and the disappearance of recipient-derived HLA antibodies. The prolonged persistence of recipient-derived PLT-specific antibodies following BMT has to our knowledge not been described previously. CONCLUSION: HPA-1a antibodies were associated with protracted PLT-transfusion dependence and significant hemorrhagic complications. Appropriate and timely laboratory investigation for HPA-specific antibodies followed by transfusion support with HPA-selected PLTs provided the cornerstone of the hemostatic management in these cases.

Prognostic significance of WT1 mRNA and anti-WT1 antibody levels in peripheral blood in patients with myelodysplastic syndromes.

Wilms tumor gene (WT1) mRNA expression in peripheral blood cells was examined in 80 patients with myelodysplastic syndrome (MDS) or acute myeloid leukemia (AML) transformed from MDS. Serum anti-WT1 antibody titers were also determined in 45 patients. Their long-term follow-up showed that the survival rate became worse as the WT1 mRNA level increased. In particular, a high WT1 mRNA level was a strong predictor of a short time to AML transformation even if adjusted by the International Prognostic Scoring System category. Moreover, high values of anti-WT1 antibody were an independent predictor of longer survival. These data may justify therapeutic strategies targeting WT1 molecules in MDS.

Immunologic characteristics and prognosis of myelodysplastic syndrome new subtype: refractory anemia with excess blasts-II.

This study was aimed to investigate the immunologic characteristics of refractory anemia with excess blasts-II (RAEB-II) which belongs to a new subtype of World Health Organization (WHO) classification of myelodysplastic syndrome (MDS) and to screen out the independent immunologic prognostic factors of MDS. 35 cases of adult patients with de novo MDS were investigated. The immunofluorescent analysis by multiparameter flow cytometry was performed at the double gating of CD45/SSC to determine the immunophenotype of MDS cells in all cases. All patients were followed up. 47 cases of acute myeloid leukemia (AML) M1, 51 cases of AML-M(2) and 38 cases of acute lymphocytic leukemia (ALL) were selected as control. Software SPSS 13.0 was applied to analyze all the related data. The results showed that the positive expression rate of HLA-DR in RAEB-II was 100%, which was high in sensitivity and specificity. CD13 (94.74%), CD33 (84.21%) and CD117 (78.95%) were also highly expressed in RAEB-II. CD13 in RAEB-II was significantly higher than that in refractory cytopenia with or without multilineage dysplasia (RA/RCMD) (p < 0.01) and REAB-I (p < 0.05); CD33, CD117 (p < 0.05) and stem cell antigen CD34 (p < 0.01) in RAEB-II were significantly higher than that in RCMD (p < 0.01), but no statistically significant difference was found as compared with RAEB-I (p > 0.05). Compared with AML-M(1) and AML-M(2), no significant difference of CD13 and CD117 in RAEB-II was found (p > 0.05). CD33 (p < 0.01) and CD34 (p < 0.05) were significantly lower than that in AML-M(1), but no significant difference was found as compared with AML-M(2) (p > 0.05); CD15 (p < 0.01) and CD11b (p < 0.05) was significantly lower than that in M(2), but no significant difference was found as compared with AML-M(1) (p > 0.05); MPO was significantly lower than that in AML-M(1) and M(2) (p < 0.05); HLA-DR was significantly higher than that on AML-M(2) (p < 0.05), but no significant difference was found as compared with AML-M(1) (p > 0.05). RAEB-II did not express CD2, CD3, CD5 and CD8 (positive rate 0%, p < 0.01) when compared with T-ALL; CD4 (p < 0.05) and CD7 (p < 0.01) were significantly lower than that in T-ALL. RAEB-II did not express CD19 and CD20 (positive rate 0%, p < 0.01) as compared with B-ALL; CD10, CD22 and cCD79a were significantly lower than that in B-ALL (p < 0.05). CD117 (p = 0.0197) and MPO (p = 0.0085) were the two prognostic immunological antigens as regards the overall survival (OS) of MDS; CD117 (p = 0.003) was the single parameter in Cox regression. It is concluded that RAEB-II expresses mainly myeloid antigen without or with little expression of lymphoid antigen. Unique individual immunophenotypic features can be detected in patients with RAEB-II. HLA-DR can be a specific parameter to distinguish the other subtypes of MDS. CD117 may be an independent prognostic immunological antigen as regards OS of MDS.

Defective cytotoxicity of T lymphocytes in myelodysplastic syndrome.

OBJECTIVE: The capacity of mononuclear blood cells to form autoreactive cytotoxic T lymphocytes was investigated in order to elucidate the mechanism of successful immunosuppressive therapy in some myelodysplastic syndrome (MDS) patients (autoreactivity studies). The failure in autoreactivity studies raised the question of alloreactive cytotoxic T lymphocyte formation in MDS (alloreactivity studies). MATERIALS AND METHODS: Sixteen MDS patients and relevant controls were examined. Autoreactive lymphocytes directed against autologous bone marrow mononuclear cells and alloreactive lymphocytes directed against unrelated third-party cells were tested using cytotoxicity assay. In addition, we used one-way mixed lymphocyte reaction, human androgen receptor test for clonality detection, and enzyme-linked immunosorbent assay kits for tumor necrosis factor and interferon-gamma testing. RESULTS: We did not confirm the presence of autoreactive T cells in eight of nine MDS patients tested. The response to allogeneic cells was impaired in 11 of 16 MDS patients, more often in refractory anemia (RA; 80%) than in RA with ring sideroblasts (40%). Interestingly, the response to allogeneic cells in mixed lymphocyte reaction was normal in all MDS patients. T lymphocytes were polyclonal in all but one patient. Tumor necrosis factor and interferon-gamma level in supernatants of mononuclear cells was significantly reduced in RA. CONCLUSION: The presumed autoaggressive T cells were not confirmed in MDS in our experimental arrangement. Alloreactivity studies demonstrated the impairment of effector cytotoxic phase of cell-mediated immunological reaction in MDS, namely in RA. The significance of our finding of defective cytotoxicity for pathogenesis, clinical course, and even for therapy is discussed together with other immunological defects reported so far.

Clinical significance of Th1/Th2 ratio in patients with myelodysplastic syndrome.

In this study, we attempted to evaluate the clinical significance of T helper 1 (Th1)/T helper 2 (Th2) ratio in patients with myelodysplastic syndrome (MDS), five refractory anaemia (RA), four refractory anaemia with ringed sideroblasts (RARS), 31 refractory cytopenia with multilineage dysplasia (RCMD), nine refractory anaemia with excess blast-1 (RAEB-1) and seven refractory anaemia with excess blast-2 (RAEB-2). Intracellular interleukin-4 (Th2 cytokine) and interferon-gamma (Th1 cytokine) production was assessed in CD4+ T lymphocytes activated by phorbol 12-myristate 13-acetate and ionomycin using flow cytometry. Mean Th1/Th2 ratios in each MDS group were as follows: RA/RARS, 8.8 (95% CI, 5.8-11.8), RCMD, 14.7 (95% CI, 9.5-19.9), RAEB-1, 10.6 (95% CI, 4.6-16.6), RAEB-2, 12.8 (95% CI, 3.0-22.7) and control 12.8 (95% CI, 9.6-16.1). There were no significant differences in Th1/Th2 ratio in the RA/RARS, RCMD, RAEB-1 and RAEB-2 subgroups when compared to controls. Because Th1/Th2 ratio in the RCMD group was widely distributed, we divided RCMD patients according to Th1/Th2 ratio into three groups (low, normal and high Th1/Th2 groups). There were no differences in severity of cytopenia among the three above groups. However, the percentage of CD8 cells in the low Th1/Th2 group was significantly lower than those in the high group (P < 0.01). These data suggest that Th1/Th2 imbalance induces CD4/CD8 imbalance, and serves as a marker of the biological interplay in immune regulation.

[Immune pathophysiology of refractory anemias].

Among different immune pathophysiologies of anemia, those of bone marrow failure syndromes such as aplastic anemia and myelodysplastic syndrome are most difficult to understand. An increase in the proportion of glycosylphosphatidyl-inositol anchored protein-deficient cells has been identified as the best marker for the presence of immune pathophysiology in this elusive syndrome. The significance of detecting small populations of such paroxysmal nocturnal hemoglobinuria (PNH)-type cells was substantiated by a recent observation that PNH-type cells arose from a donor-derived hematopoietic stem cell with a PIG-A mutation in an aplastic anemia patient with late graft failure which responded well to immunosuppressive therapy. Identification of auto-antigens capable of inducing cytotoxic T cells against hematopoietic stem cells is necessary to prove the escape of PIG-A mutant clone from the immune system attack using animal models.

Myelodysplastic syndrome with trisomy 8 associated with Behçet syndrome: an immunologic link to a karyotypic abnormality.

Myelodysplastic syndrome (MDS) in children is often associated with chromosomal anomalies and trisomy 8 is a characteristic karyotypic feature in up to 20% of the cases. Behçet disease is a rare multisystem inflammatory disorder characterized by recurrent mouth and genital ulcers. MDS with trisomy 8 has been observed in adult patients with Behçet syndrome with some cases developing prior to the clinical manifestations of the latter. We present a female with a similar association and explain the importance of identifying the coexisting conditions. The immunological abnormalities, which may be observed in MDS and their possible mechanisms, are also discussed.

Transformation of childhood MDS-refractory anemia to acute lymphoblastic leukemia.

Myelodysplastic syndromes (MDS) are clonal disorders of hematopoietic stem cell. Patients have a deteriorating course with about 30% evolving into acute leukemias usually of the myeloid phenotype. Evolution into acute lymphoblastic leukemia is a rare and intriguing phenomenon seen in far less than 1% of adult cases, and extremely rare in pediatric population. We report a case of childhood MDS-refractory anemia transforming into acute lymphoblastic leukemia after an interval of 21 months since presentation and being on cyclosporine therapy for 9.5 months. The case raises further questions about the biology of MDS and the potential role of cyclosporine in leukemic transformation.

Anti-erythroblast autoimmunity in early myelodysplastic syndromes.

BACKGROUND AND OBJECTIVES: Autoimmune phenomena, mainly directed against red blood cells are described in myelodysplastic syndromes (MDS), particularly early MDS, i.e. refractory anemia (RA) and RA with ringed sideroblasts (RARS). Dysregulation of apoptosis and immunoregulatory cytokines are thought to play a role in the pathogenesis of MDS. DESIGN AND METHODS: This work was aimed to investigate anti-erythroid autoimmunity in unstimulated and mitogen-stimulated peripheral blood and bone marrow cultures of 26 patients with early MDS (RA and RARS), and to relate its presence with apoptotic markers and cytokine production. Bone marrow cytokine production in culture supernatants, and caspase-3 and nuclear factor-kappaB activity in cell extracts were tested by enzyme-linked immunosorbent assays. RESULTS: Fourteen of the 26 (53.8%) patients showed the presence of autoantibodies in bone marrow cultures, whereas none displayed a positive direct antiglobulin test in peripheral blood cultures. Incubation of culture supernatants from positive patients with autologous CD45- enriched-cell suspensions showed that the autoimmune reaction was directed against autologous erythroblasts. These patients had mild signs of hemolysis and increased numbers of erythroblasts, compared with negative patients. Patients with anti-erythroblast autoimmunity displayed higher caspase-3 activity and lower tumor necrosis factor-alpha and interleukin-4 production than did negative patients. INTERPRETATION AND CONCLUSIONS: Half of the patients with early MDS showed autoimmunity against erythroblasts. This evidence might support a more rationale use of steroid therapy in these patients. The lower levels of cytokines in patients with anti-erythroblast autoimmunity are consistent with the suggested hypothesis that the autoimmune phenomena observed in MDS are probably initiated and perpetuated through alterations of pro-inflammatory and/or immunoregulatory cytokine production.

Immature and mature monocyte-derived dendritic cells in myelodysplastic syndromes of subtypes refractory anemia or refractory anemia with ringed sideroblasts display an altered cytokine profile.

Dendritic cells (DC) are pivotal for T cell-mediated immunity. We investigated the early and terminal maturation of monocyte-derived DC (MoDC) in myelodysplastic syndromes (FAB subtypes refractory anemia (MDS-RA) or refractory anemia with ringed sideroblasts (MDS-RARS)). Immature MoDC were obtained by culture of monocytes with GM-CSF and IL-4 for 8 days. To obtain mature MoDC, TNF-alpha was added during the final three culture days. T cell proliferation and T cell cytokine secretion in mixed lymphocyte reactions (MLR) unveiled a strong reduction of allostimulatory capacity of mature but also of immature MoDC from MDS patients. Immature MoDC from MDS patients exhibited an almost normal immunophenotype, but secreted substantially less IL-12 and more IL-10 in response to LPS/IFN-gamma than normal controls. Terminal addition of TNF-alpha to GM-CSF/IL-4 treated monocytes failed to extinguish cytokine production by MDS MoDC and failed to induce the expected membrane upregulation of costimulatory and other ligands as in normal controls. While our data provide further support for previous studies that have indicated an impaired differentiation of immature towards mature MoDC, they also clearly demonstrate a qualitatively and quantitatively altered cytokine secretion at the level of immature MoDC, which may in part explain the reduced allostimulatory capacity of these cells. These alterations may contribute to immune modulation of the clinical phenotype of marrow failure in MDS, and may have to be considered when designing DC-based immunotherapeutic strategies for MDS.

[Auto- and alloreactivity of T lymphocytes in myelodysplastic syndrome]. / Auto- a aloreaktivita T lymfocytu u myelodysplastického syndromu.

BACKGROUND: Successful therapy with ATG and cyclosporine A in some myelodysplastic syndrome (MDS) patients led us to study the existence of T cells attacking autologous hemopoietic cells. In our study, we attempted to give the direct prove of autoreactive T cells in MDS (autoreactivity analysis). Simultaneously, we analysed the capacity of MDS patients to respond to allogeneic cells from unrelated individuals (alloreactivity analysis). METHODS AND RESULTS: Autoreactive lymphocytes directed against own bone marrow mononuclear cells were analysed using the modification of cell mediated cytotoxic reaction. With one exception we did not confirm the presence of autoreactive T cells among 10 patients examined. Analysis of alloreactivity was performed by means of standard cell mediated cytotoxic reaction and mixed lymphocyte reaction. Surprisingly, the cytotoxic response to allogeneic cells was negative in 11 MDS patients from 16 analysed. When comparing refractory anaemia (RA) and refractory anaemia with ring sideroblasts (RARS) patients, the proportion of negative results was higher in RA (78 %) than in RARS (40 %). In mixed lymphocyte reaction, the response of MDS cells to allogeneic cells of unrelated individual was positive in all tested patients. The preliminary testing of TNF and IFNgamma secretion examined in supernatants of effector cells showed impaired levels of both cytokines in RA and normal levels in RARS in accordance with the findings achieved in alloreactivity analysis. CONCLUSIONS: Autoreactive T cells were not found in MDS patients using our experimental arrangement. Analysis of alloreactivity showed the defect in effector--cytotoxic--phase of cell mediated cytotoxic reaction in the majority of MDS patients. The initial phase of this reaction represented in vitro by mixed lymphocyte reaction gave normal results. The possible reasons of disturbed alloreactivity and its relevance to immunity in MDS are commented in discussion.

[Immunosuppressive treatment of the myelodysplastic syndrome]. / Immunosuppressiv behandling af det myelodysplastiske syndrom.

INTRODUCTION: The myelodysplastic syndrome (MDS) is featured by cytopenia in one or more cell lineages. Until recently the only possible treatment was supportive care with transfusions and antibiotics, but new options have now become available. In this article the results of immunosuppressive treatment are described and discussed. MATERIAL AND METHODS: We present seven patients who were treated with antithymocyte globulin (ATG) and cyclosporine. Previous series of patients with MDS treated with ATG are summarized. RESULTS: Two of the seven patients treated with ATG and cyclosporine achieved a complete response, one had a partial response and one had a minor response. DISCUSSION: In MDS an acquired insult to the hemopoietic stem cell leads to impaired differentiation and myelodysplasia. A model of MDS pathophysiology suggests that transformation of normal stem cells induces an autoimmune T cell response with the bone marrow as the target organ. This autoimmune attack results in chronic overproduction of pro-apoptotic cytokines, especially TNF-alpha. This may contribute to a dysplastic morphology and increased apoptosis in the marrow. It is suggested that the mechanism of action of ATG in MDS may involve elimination of CD8+ lymphocyte mediated suppression of granulocyte/monocyte progenitor cells.

Autologous lymphocytes inhibit hemopoiesis in long-term culture in patients with myelodysplastic syndrome.

OBJECTIVE: The current therapy of myelodysplastic syndrome (MDS) is unsatisfactory and comprises mainly supportive treatment or antileukemic chemotherapy. Recent studies about successful immunosuppressive therapy suggest an autoimmune mechanism in subtypes of myelodysplastic syndrome. PATIENTS AND METHODS: To investigate this hypothesis, bone marrow mononuclear cells (MNC) from 15 patients with low-grade MDS, refractory anemia, and refractory anemia with ringed sideroblasts (RA and RARS), and from 7 normal donors were depleted of CD2(+), CD5(+), and CD7(+) lymphocytes using magnetic cell sorting. Depleted and nondepleted MNC were seeded onto irradiated allogeneic bone marrow stroma and the generation of colony-forming-cells (CFC), the clonal origin of hemopoietic progenitor cells in long-term bone marrow culture (LTC), was compared. RESULTS: The capacity of MNC from 7 healthy donors to generate hemopoiesis remained unchanged in the lymphocyte-depleted LTC. In contrast, cultures initiated with lymphocyte-depleted MNC from patients with RA and RARS exhibited a significantly increased generation of CFC compared with the corresponding nondepleted cultures. Microsatellite analysis in 6 patients revealed that a significantly increased number of CFC grown in lymphocyte-depleted LTC showed no allelic loss, suggesting an outgrowth of normal hemopoietic cells. CONCLUSION: These results provide a rationale for the recently described successful treatment of MDS with immunosuppressive therapy. We suggest that in certain subtypes of MDS the residual normal hemopoiesis is suppressed by autoimmune mechanisms, eventually allowing the expansion of the abnormal clone.

[Immunologic phenomena as the first sign of myelodysplastic syndrome]. / Immunologische verschijnselen als eerste uiting van het myelodysplastisch syndroom.

Two patients, men aged 77 and 66 years, presented with a vasculitis. Due to an abnormal blood smear they were referred to the internist, who subsequently diagnosed a myelodysplastic syndrome (MDS). They were initially treated with a high dose of corticosteroids and this dosage later became a maintenance dose. Immunological phenomena occur in 10-14% of MDS patients and seem to have a poor prognosis. Most patients respond well to treatment with corticosteroids. Occasionally, favourable haematological responses to corticosteroid therapy are seen, although this was not the case in the two patients described. When patients present with an immunological disorder, such as a vasculitis or an autoimmune disease, it is important to be aware of the possibility of an underlying MDS.

Immunohematological findings in myelodysplastic syndrome.

BACKGROUND: Few immunohematological studies have been done in myelodysplastic syndrome (MDS). METHODS: Twenty-nine MDS patients were retrospectively evaluated with a direct antiglobulin test (DAT), antibody screening, serum electrophoresis and immunoelectrophoresis. Clinical and laboratory studies (hemoglobin level, reticulocyte count, DHL, total and indirect bilirubin) were done simultaneously, as well as the French-American-British subtype and bone marrow biopsy findings. RESULTS: Alloantibodies were demonstrated in 17 patients (58.6%), autoantibodies in 10 (34.4%) patients and cold agglutinin in 18 (62%) patients. DAT was mediated by only IgG in 8 patients (80%), by IgG and C3 in 1 patient (10%) and by IgG, IgA and C3 in 1 (10%) patient. No hemolytic disease occurred in patients with autoantibodies. Increased serum gammaglobulin was observed in 16 (54.4%) patients. There was no correlation between the incidence of allo-/autoantibodies and the gammaglobulin level (p = 0.937) and the presence of lymphocyte infiltrates in bone marrow biopsies (p = 0.156). No significant difference was observed when the incidence of autoantibodies and number of red blood cell transfusions were compared (p = 0.334). Patients with refractory anemia and refractory anemia with ringed sideroblasts subtypes had a higher incidence of allo-/autoantibodies than other MDS subtypes (p = 0.03). CONCLUSION: Patients with MDS, in particular refractory anemia and refractory anemia with ringed sideroblasts have a high incidence of allo- and autoantibodies, probably related to intrinsic immune disorder, without clinical or laboratory hemolysis.

Coincident myelodysplastic syndrome and T-cell large granular lymphocytic disease: clinical and pathophysiological features.

Myelodysplastic syndrome (MDS) and T-cell large granular lymphocytic disease (T-LGL) are bone marrow failure disorders. Successful use of immunosuppressive agents to treat cytopenia in MDS and LGL suggests a common pathophysiology for the two conditions. Of 100 patients with initial diagnoses of either MDS or T-LGL referred to the National Institutes of Health for immunosuppressive treatment of cytopenia, nine had characteristics of both T-LGL and MDS (T-LGL/MDS). Fifteen patients with T-LGL received cyclosporin (CSA) (10 responses). Eight out of nine patients with T-LGL/MDS received CSA (two responses) and one patient received ATG (one response). Of 76 patients with MDS, eight received CSA (one response) and 68 received ATG (21 responses). The response to immunosuppression was significantly lower in patients with T-LGL/MDS and MDS than in patients with T-LGL disease alone (28% vs. 66%, P = 0.01). The proportion of T-helper cells and T-suppressor cells with an activated phenotype (HLA-DR(+)) was increased in patients with T-LGL, T-LGL/MDS and MDS, but the increase in activated T-suppressor cells in patients with T-LGL/MDS was not statistically significant. Autoreactive T cells may suppress haematopoiesis and contribute to the cytopenia in T-LGL and some patients with MDS, leading to T-LGL/MDS. The lower response rate of MDS or T-LGL/MDS to immunosuppression, compared with T-LGL alone, may reflect the older age and intrinsic stem cell abnormalities in MDS and T-LGL/MDS patients.