In conclusion the shift of the cytokine expression profile from a Treg and Th2 phenotype before treatment toward a Th1 phenotype one month after treatment with arsenic/IFN/zidovudine, and before maximal clinical response and ATL cell loss, may play an important role in restoring an immune response that can participate in the eradication of ATL cells and the prevention or control of opportunistic infections. Here, IFNA1 is linked to Opportunistic infection.