The Marasco laboratory at Dana-Farber Cancer Institute (DFCI) has constructed two phage display libraries containing 12 billion (Mehta I) and 15 billion (Mehta II) human sFv antibody phages, which the Center of Therapeutic Antibody Engineering will use to provide NFCR scientists with high affinity human antibodies to support their basic cancer research and/or clinical studies for the treatment of cancer. Description of the Mehta I and II human sFv antibody phage libraries is provided below. Questions related to future commercial licensing of antibodies derived from the Mehta I and II human sFv antibody phage display libraries should be directed to Dr. Wayne A. Marasco.

Construction

To construct the Mehta I and II sFv-phage libraries, we isolated 2.75 x 10⁸ B cells from the peripheral blood of 57 volunteers at DFCI. The initial V_H and V_L repertoires consisted of 3.5 x 10⁸ V_H, 120 x 10⁶ V_kappa and 80 x 10⁶ V_lambda transformants. The Mehta I library was constructed through the random assembly of 2.75 x 10⁸ V_H genes with 1.6 x 10⁶ V_kappa and 1.6 x 10⁶ V_lambda genes to yield 12 billion member library. The Mehta II library was constructed identically except that V_kappa genes were not used and a 15 billion member library was obtained.

Characterization

The genetic diversity of the libraries was determined by DNA sequence analysis of unselected sFv-phage from each library. Genetic studies on circa 100 clones have confirmed that each of the major heavy and light chain immunoglobulin germline gene families are represented. These two human sFv libraries are among a handful of the largest human sFv-phage display libraries ever made (Nissim, 1994; Griffiths, 1994; Vaughan, 1996; Sheets, 1998, de Haard, 1999).

Selection

Numerous human sFv antibodies have been isolated from the Mehta libraries. Examples are provided in the next Table.

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