Immunoregulatory agent

A method for regulating Rac-activating activity of DOCK2, the method comprising at least one of:

• (i) forming an immune-privileged site by administering to a patient in need of treatment an effective amount of cholesterol 3-sulfate, a pharmacologically acceptable salt thereof, or a solvate thereof, to regulate DOCK2-mediated Rac activation;
• (ii) forming an immune-privileged site by administering to a patient in need of treatment an effective amount of a SULT2B1b protein, or an expression vector of the SULT2B1b protein;
• and
• (iii) destroying an immune-privileged site by administering to a patient in need of treatment an effective amount of an expression inhibition substance of the SULT2B1b protein,
• wherein:
• the SULT2B1b protein is a protein which comprises the amino acid sequence of SEQ ID NO:
• 2, or a protein which comprises an amino acid sequence formed by the deletion, substitution, or addition of 1 to 3 amino acids in the amino acid sequence of SEQ ID NO:
• 2, and acts to add a sulfonic acid group to the carbon at position 3 of cholesterol and generate cholesterol 3-sulfate, and
• the expression inhibition substance of the SULT2B1b protein is siRNA or shRNA.