Electronic Poster | Session 1

084 – Neopterin and Neurofilament Light Chain as markers of HIV-associated neurocognitive impairment in plasma and cerebrospinal fluid

Yisel Cantres-Rosario (1) – Elaine Rodriguez (1) – Valerie Wojna (1)
University of Puerto Rico, Medical Sciences Campus, University of Puerto Rico, Medical Sciences Campus, San Juan, Puerto Rico (1)

Human immunodeficiency virus (HIV) is able to enter from the periphery to the central nervous system, triggering neurocognitive impairment which can be asymptomatic, mild cognitive and motor impairment or in a few cases severe dementia. With the availability and efficacy of antiretroviral therapy, HIV patients have a better quality of life. However, HIV-associated neurocognitive disorders (HAND) still prevail in near 50% of the treated patients. In this study, we used ELISA to measure neurofilament light chain (NF-L) and neopterin, as markers of neuronal injury and immune activation, respectively. We used plasma and cerebrospinal (CSF) samples obtained from HIV-seropositive (HIV+) patients (n=35) at different stages of HAND, compared to HIV-seronegative controls (n=10). HIV+ patients were subjected to standard laboratory tests (including viral load and CD4+ cell count) and neuropsychological tests (eight domains). Statistical tests included Mann-Whitney, Kruskal-Wallis and Spearman’s correlation. We hypothesize that HIV+ patients have increased levels of NF-L and Neopterin in plasma and CSF, compared to controls. We did not detect differences in levels of NF-L in the CSF, between controls and HIV+ patients. However, there is an inverse correlation between the levels of NF-L in CSF and the neuropsychological tests z-score (NPZ) (r = -0.345, p = 0.039). Moreover, HIV+ patients have higher levels of NF-L in plasma (p = 0.0024) compared to controls. The levels of NF-L in plasma are also inversely correlated with NPZ (r = -0.428, p = 0.0092). Neopterin is higher in the CSF of HIV+ patients compared to controls (p = 0.011), and is directly correlated with the viral load in plasma (r = 0.656, p = 0.057) and CSF (r = 0.873, p < 0.0001). Interestingly, neopterin levels were higher in the plasma of controls than HIV+ patients (p<0.0001), and where directly correlated to the viral load in plasma (r = 0.589, p = 0.0164), as well. In summary, neopterin increases and correlates with viral load in the CSF; while NF-L increases and inversely correlates with neurocognitive performance in plasma. Neopterin is a better marker of HIV-associated neuropathology in the CSF, while NF-L is a better marker in plasma. Our results point to an interesting combination of two markers of HIV-associated neuropathology and CNS immune activation.