Methods and pharmaceutical compositions for blocking suppression of immune defense mechanisms using an antibody, a factor, or an antisense peptide

A method for blocking suppression of at least one cell-mediated cytotoxicity mechanism selected from the group consisting of the cytotoxicity mechanisms mediated by the natural killer (NK) cells and lymphokine activated killer (LAK) cells in a cancer patient comprising administering to a cancer patient an antibody capable of blocking the activity of a peptide that suppresses a cell-mediated cytotoxicity mechanism selected from the group consisting of the cytotoxicity mechanisms mediated by the NK and LAK cells, the peptide capable of inducing a detectable decrease in the structuredness of the cytoplasmic matrix (SCM) in lymphocytes isolated from a patient with cancer (an SCM factor peptide) in a quantity sufficient to block suppression of at least one of the cytotoxicity mechanisms mediated by the NK and LAK cells to a degree such that at least one of the NK and LAK activities is about 100% as efficient as in cells in which the SCM-factor peptide is not present, as measured by lysis of susceptible target cells by lymphocytes isolated from the patient, the antibody being an antibody that specifically binds a domain of the SCM-factor peptide to inhibit the effect of the SCM-factor peptide and suppressing at least one of the cytotoxicity mechanisms mediated by NK and LAK cells, the domain being selected from the group consisting of F-L-M-I-D-Q-N-T-K-V-P-L-F-M-G-K (SEQ ID NO:2), and a domain related to (SEQ ID NO:

• 2) by one or more conservative amino acid substitutions selected from the group consisting of one of isoleucine, valine, and leucine for any other of isoleucine, valine, and leucine;
• aspartic acid for glutamic acid and vice versa;
• asparagine for glutamine and vice versa;
• and serine for threonine and vice versa.