JACALIN, A LECTIN THAT INHIBITS IN-VITRO HIV-1 INFECTION, INDUCES INTRACELLULAR CALCIUM INCREASE VIA CD4 IN CELLS LACKING THE CD3 TCR COMPLEX/

The lectin jacalin interacts with the CD4 cell surface antigen; this l ectin inhibits in vitro infection by human immunodeficiency virus type 1 without preventing virus binding on the host cell. The infection pr ocess is known to involve cellular events triggered by the binding of the viral external glycoprotein pp120 to CD4. Herein we demonstrate th at jacalin induces cell signaling directly through the CD4 antigen and that independently of the CD3/TcR complex. The capacity of jacalin to trigger cell signals through the CD4 molecule is discussed in relatio n to its ability to inhibit HIV infection.