Hospital for Special Surgery

Funding for Human Subjects Research:

DOE: Office of Biological and Environmental Research (OBER)

$0.00 for: Fiscal Year 2007
Project in no cost extension to 10/21/06. Study was completed.
Percent of funding associated with the use of human subjects: 0

Information on Use of Human Subjects:

This project does not involve the use of multiple protocols/subprojects.

Institutional Review Board (IRB) Review:
Type of Review: Full Board
Approving Institution: Hospital for Special Surgery
Most recent approval: 01/20/06
IRB approval number: 23076
Explanation of IRB approval:
Study ended.

Number of human subjects who participated in this project/protocol/subproject in the last reporting period: 22
Reporting period for number of human subjects: Other: 10/01/05 to 09/30/06
Explanation:

Study ended.

Type(s) of Human Subjects Involvement:

Collection of personally identifiable bodily materials (blood or blood products, urine, cells, tissue, teeth, organs, excreta, etc):

• Using bodily materials collected specifically for this project.

(a. Objectives, b. Methodology, c. Ionizing Radiation, Radioactive Substances, or Chemical Substances to which human subjects are exposed, d. Involvement of Human Subjects [d.1. procedures used, d.2. risks if any])

The long range goal of the proposed research was to determine the mechanisms that block the production of "bad" autoreactive B cells that may attack the body. These mechanisms are functional in healthy humans but defective in most patients with autoimmune diseases including rheumatoid arthritis (RA). The objectives of the grant proposal were to determine how methotrexate and anti-TNF-alpha agents that remain the standard of care in RA can block the production of these "bad" autoreactive B cells that may produce antibodies that can attack the joints of these patients.

We obtained peripheral blood from six RA patients previously studied when naïve of any medication and who clinically improved after treatment with methotrexate (three patients, RA01, RA02, and RA03), anti-TNF-alpha agent (RA05 treated with adalimumab and RA11 with etanercept), or both (RA01 with methotrexate and infliximab). We sorted single mature naïve B cells, cloned and expressed their antibodies in vitro, and tested their polyreactivity and HEp-2 reactivity by Enzyme-Linked ImmunoSorbent Assay (ELISA) for comparison with their pre-treatment counterparts. The increased frequency of HEp-2 reactive and polyreactive B cells found in the pre-treatment patients remained high in mature naïve B cell compartments after treatment with methotrexate. This further solidifies our pre-treatment conclusions that revealed defects in early B cell tolerance checkpoints associated with RA. In contrast, the frequency of both polyreactive and HEp-2 reactive mature naïve B cells decreased in all RA patients who received anti-TNF- alpha agents. Thus, methotrexate appears to act downstream from the early impaired B cell tolerance checkpoints and does not correct the accumulation of peripheral autoreactive mature naïve B cells in RA patients. In contrast, anti-TNF-alpha therapy seems to correct the defective peripheral B cell tolerance checkpoint and results in the apparent normal removal of polyreactive and HEp-2 reactive B cells in the mature naïve B cell compartment of treated RA patients.