<prompt> Autoimmunity can be caused due to all of the all following except -The pressure of forbidden clonesExpression of cryptic antigensNegative selection of T-cells in the thymusInappropriate expression of the MHC proteins  <response>: Altered T or B cell function also contribute to autoimmunity. Enhanced helper T cell and decreased suppressor T cell functions have been suggested as cause of immunity. - defect in the tymus, in stem cell development and macrophage function have also been postulated as causes. Reference: Anathanarayan panikers 9th edition, pg no: 179 p 