Evaluation of a filtration lymphocytapheresis (LCP) device for use in the treatment of patients with rheumatoid arthritis. 1991.

Abstract

Abstract: Guest Editor's Introduction: Cell adhesion on a material is caused by the interaction between them and related to the material characteristics including chemical structure, surface charge, wettability, smoothness, and microstructure such as microdomain structure. In addition, Nishimura of Asahi Medical Co. found that the size of the material is important particularly in the case of lymphocyte adhesion. Based upon this result Asahi Medical Co. developed lymphocyte removal filters by use of ultra fine fibers having a diameter of 1.7 μm. The filter was first used for leukocyte filters for blood transfusion, and then applied for therapeutic use in the treatment of patients with various hematological and autoimmune diseases. This paper describes the specification of the filter and clinical application for the treatment of rheumatoid arthritis. This paper was printed in Artificial Organs, vol. 15, page 180–188 (1991) and reprinted here with permission.A practical on‐line lymphocytapheresis (LCP) system using a leukapheresis filter (Cellsorba, Asahi Medical Co.) was evaluated in six patients with refractory rheumatoid arthritis. This filter consists of nonwoven fine polyester fiber wound around a porous cylinder. The blood was passed through the polyester fiber at a flow rate of 50 ml/min for 60 min. LCP was carried out once a week in the first month and biweekly in the next 2 months. An average of 98% of the leukocytes that entered the filter (1.27 × 1010 cells) and 100% of the lymphocytes that entered the filter (3.66 × 109 cells) were removed in the first LCP. A total of 96.6% of the platelets and 2.7% of the erythrocytes that entered the filter were also removed. All of the patients showed clinical improvement in morning stiffness, Lansbury articular index, and functional capacity, with no adverse reaction. The number of circulating lymphocytes erythrocytes, and platelets and the concentration of various serum components showed no significant change during the treatments. This LCP system required no fresh frozen plasma, albumin, or other blood transfusion. The number of circulating lymphocytes decreased to 65–70% of the pretreatment circulating lymphocyte count at the last procedure, with a decrease in the ratio of Leu3a positive cells to Leu2a positive cells. The proliferative response to phytohemagglutinin and concanavalin A was improved. These data suggest that LCP to remove ∼3 × 109 lymphocytes once a week or biweekly has an immunomodulatory effect.