FIG. 4.

env sequences from neurovirulent HIV-1 (A) and FIV (B) strains induce STAT/JAK and MMP expression. (A) STAT-1 and JAK-1 expression was increased in primary human macrophages infected with HAD HIV-1 clones compared to HIV-ND-infected and uninfected cells. Similarly, MMP-2 and -9 protein levels in conditioned media from human macrophages were significantly greater following infection with HAD HIV strains compared to those in HIV-ND clones. (B) Infection of feline macrophages with V₁CSF, Petaluma, or chimeric (FIV-Ch) FIV strains revealed that STAT-1α and JAK-1 levels were higher in macrophages infected by V₁CSF and FIV-Ch compared to Petaluma-infected and uninfected cells. MMP-2 and -9 levels were also significantly higher in conditioned media from feline macrophages infected with V₁CSF or FIV-Ch. Data are expressed as fold increases over uninfected controls and represent the mean ± standard deviation of three experiments. Significant differences between neurovirulent and nonneurovirulent viruses are indicated (Tukey-Kramer test; ∗, P < 0.01; ∗∗, P < 0.001).