Table 2.

Findings against a crucial role of CXCR4 as a relevant target for anti-HIV drug development.

Key aspect	Observation	References
HIV transmission, early viral spreading	almost exclusively accounted for by R5 viruses	63
HIV evolution	CXCR4 use occurs only in 50% of individuals infected with subtype B virus; almost irrelevant for other viral subtypes	4
Spectrum of target cells	X4 viruses do not replicate efficiently in primary macrophages or dendritic cells	64
Response to cART	Reported more rapid disappearance of CXCR4-using strains than of R5 viruses due to immunological reconstitution	65