title: Effect of cA2 anti-tumor necrosis factor-alpha antibody therapy on hematopoiesis of patients with myelodysplastic syndromes.
abstract: OBJECTIVE
  Tumor necrosis factor alpha (TNF-alpha) plays a prominent role in the pathophysiology of myelodysplastic syndromes (MDS). The aim of this study was to explore the biological and immunoregulatory effect of the treatment with the anti-tumor necrosis factor-alpha monoclonal antibody cA2 on bone marrow (BM) progenitor/precursor and stromal cells and lymphocyte subsets, as well as the clinical response in MDS patients.
  
  
  METHODS
  Ten low-intermediate risk MDS patients received i.v. cA2 (3 mg/kg) at weeks 0, 2, 6, and 12. The number, survival, and clonogenic potential of BM progenitor/precursor cells, the hematopoiesis-supporting capacity of BM stromal cells, and the lymphocyte activation status were investigated in the patients at baseline and following treatment using flow cytometry, clonogenic assays, and long-term BM cultures (LTBMC). Clinical response was evaluated according to standardized criteria.
  
  
  RESULTS
  cA2 administration reduced the proportion of apoptotic and Fas+ cells in the CD34+ cell compartment (P = 0.0215 and P = 0.0344, respectively) and increased the clonogenic potential of BM mononuclear and CD34+ cells (P = 0.0399 and P = 0.0304, respectively) compared with baseline. The antibody reduced tumor necrosis factor-alpha levels in LTBMC supernatants (P = 0.0043) and significantly improved the hematopoiesis-supporting capacity of LTBMC adherent cells. The proportion of activated peripheral blood and BM T-lymphocytes decreased significantly after treatment, suggesting an immunomodulatory effect of cA2. Two patients displayed minor hematologic responses whereas the remaining patients displayed stable disease with no disease progression.
  
  
  CONCLUSIONS
  The encouraging biological insights from cA2 administration may be useful in conducting further clinical trials using cA2 for selected MDS patients, particularly those with evidence of immune-mediated inhibition of hematopoiesis.
authors.affiliation: Department of Hematology, University of Crete School of Medicine, Heraklion, Crete, Greece.
authors.forename: Anna
authors.initials: A
authors.lastname: Boula
authors.forename: Michael
authors.initials: M
authors.lastname: Voulgarelis
authors.forename: Stavroula
authors.initials: S
authors.lastname: Giannouli
authors.forename: George
authors.initials: G
authors.lastname: Katrinakis
authors.forename: Maria
authors.initials: M
authors.lastname: Psyllaki
authors.forename: Charalambos
authors.initials: C
authors.lastname: Pontikoglou
authors.forename: Fotini
authors.initials: F
authors.lastname: Markidou
authors.forename: George D
authors.initials: GD
authors.lastname: Eliopoulos
authors.forename: Helen A
authors.initials: HA
authors.lastname: Papadaki
mesh_terms: D000368:Aged; D000911:Antibodies, Monoclonal / Q000627:therapeutic use*; D017209:Apoptosis; D005260:Female; D005434:Flow Cytometry; D005765:Gastrointestinal Agents / Q000627:therapeutic use*; D006410:Hematopoiesis / Q000187:drug effects*; D006801:Humans; D000069285:Infliximab; D008213:Lymphocyte Activation; D016131:Lymphocyte Subsets; D008297:Male; D008875:Middle Aged; D009190:Myelodysplastic Syndromes / Q000097:blood / Q000188:drug therapy* / Q000276:immunology*; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors
chemical_list: D000911:Antibodies, Monoclonal; D005765:Gastrointestinal Agents; D014409:Tumor Necrosis Factor-alpha; D000069285:Infliximab