Tehran University of Medical Sciences Iranian Journal of Allergy, Asthma and Immunology 1735-1502 16 5 2017 10 28 433 442 EN Hossein Ahmadi Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran Ahmad Reza Jamshidi Rheumatology Research Centre, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran Mahdi Mahmoudi Rheumatology Research Centre, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran Farhad Gharibdoost Rheumatology Research Centre, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran Mahdi Vojdanian Rheumatology Research Centre, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran Mohammad Javad Fattahi Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran AND Institute for Cancer Research (ICR), School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran Noushin Rastkari Center for Air Pollution Research (CAPR), Institute for Environmental Research (IER), Tehran University of Medical Sciences, Tehran, Iran Zahra Aghazadeh Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran Abbas Mirshafiey Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran 2017 01 23 2017 03 12 The aim of this study was to investigate the effect of β-D-mannuronic acid (M2000) on hematological parameters in patients with active rheumatoid arthritis. This study was conducted on 25 patients with active rheumatoid arthritis (RA) (identifier: IRCT2014011213739N2). M2000 was administered orally for anemic and non-anemic RA patients at a dose of 500 mg twice daily for 12 weeks. The patients were permitted to continue the conventional treatments excluding NSAIDs. Blood samples were collected at baseline, 4 and 12 weeks after drug administration and were tested for hematological parameters. Moreover, serum levels of TNF-α and IL-6 were analysed before and after M2000 therapy compared to healthy controls using enzyme linked immunosorbent assay method. We found a significant increase in the count of red blood cells and also hemoglobin (Hb) concentration (0.9 g/dL) in anemic patients after 12 weeks of M2000 therapy (p<0.02 and p<0.01, respectively). Furthermore, our results showed an improvement in Hb level (0.45 g/dL) even in non-anemic patients who were treated by M2000 (p<0.04). The leukocytosis in RA patients, significantly decreased in both anemic and non-anemic patients after 12 weeks of M2000 therapy (p<0.02 and p<0.03, respectively). The percent of neutrophils significantly increased in anemic patients (p<0.01) while in non-anemic patients it significantly decreased after 12 weeks of M2000 therapy (p<0.01). The serum levels of IL-6 and TNF-α significantly decreased after 12 weeks of M2000 therapy (p<0.01 and p<0.04, respectively). M2000 improves hematological parameters in RA patients by its potent inhibitory effect on serum levels of TNF-α and IL-6. https://ijaai.tums.ac.ir/index.php/ijaai/article/view/1275 https://ijaai.tums.ac.ir/index.php/ijaai/article/download/1275/761