<prompt> The HLA class3 region genes are impoant element inTranslate rejection phenomenonGoverning susceptibility to autoimmune diseaseImmune surveillanceAntigen presentation and elimination  <response>: Ref Robbins 9e p215 Anantha Narayana 6e p108 Class III molecules include several secreted proteins with immune functions: components of the complement system such as C2, C4, and B factor, cytokines such as TNF-a, LTA, and LTB, and heat shock proteins. 