The solution to the seven mysteries of AIDS: the 'Trojan horse'.

It is concluded that the sperm is the cause of AIDS but that HIV may slightly alter the symptoms of this disease, as compared to idiopathic CD4+ T-lymphocytopenia, or ICL, where the sperm, but not HIV, is assumed present. In the proposed mechanism, the sperm selectively accepts into its interior only macrophage-tropic HIV through its CD4+ antigens and carries this HIV into a person through four possible pathways: rectum (anal sex), genital ulcers, blood transfusions, and female circumcision. Then the sperm acts as a 'Trojan horse' by entering HLA-DR+ CD4+ T cells and releasing the HIV into these cells. The released HIV in turn mutates to a form capable of attacking CD4+ T cells. Thus the sperm by a 'Trojan horse' mechanism has changed the tropism of HIV. However, experimental evidence indicates that this mutated HIV is essentially non-toxic. In contrast, it is concluded that the sperm is extremely toxic since it is capable of inducing autoimmune reactions (by means of its CD4+ antigens) and is capable of entering and destroying HLA-DR+ CD8+ and HLA-DR+ CD4+ T cells in either the presence or absence of HIV (AIDS or ICL). Hence, the mysteries of AIDS can be explained by the presence of the toxic sperm and its complicated interactions with HIV (the 'Trojan horse' mechanism).