I was recently told that I do not need isotype controls with REAfinity Antibodies. What has changed?

One main purpose of isotype controls is to show there is no unspecific Fcγ receptor–mediated binding. REAfinity Antibodies are specifically engineered to eliminate Fcγ receptor binding, so this aspect does not need to be controlled for with an isotype control. However, to exclude other non-Fcγ receptor–mediated unspecific binding or unspecific interactions of the fluorochrome we recommend to perform such a control.