While HIV-1 continues to be well-researched, this detailed volume draws attention to other members of the Retrovirus family, namely the Human T-lymphotropic Viruses (HTLVs), featuring the most updated technical information about HTLV determination and the methods to investigate their interaction with the host immune system and interfering pathogens. The contents include essential aspects of epidemiology and virus transmission, novel and robust methodologies for studying the effects of trans-activating regulatory HTLVs  proteins, the latest techniques for genotyping and gene expression analysis, as well as cellular phenotype and dynamics.  Written in the highly successful Methods in Molecular Biology series format, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and tips on troubleshooting and avoiding known pitfalls.