CD4 and cancer: As stated above, it is our view that human susceptibility to autoimmunity and cancer are the evolutionarily acceptable side effects of the immune adaptations that evolved in early placental mammals to accommodate a fundamental change in reproductive strategy, and by reversing this process, a detuned and deregulated immune system is much better equipped to mount anti-tumor immune responses against cancers but is also resistant to chronic CD4 driven autoimmune disease.