Evaluation of commercially available assays of neopterin and β2-microglobulin for the assessment of disease progression in FIV-infected cats

Serum or plasma samples from cats at different stages of feline immunodeficiency (FIV) infection and from uninfected cats were tested using immunoassays designed to detect human neopterin and β2-microglobulin (β2M). The results obtained from the anti-human neopterin assay did not correlate with infection status, time post-infection, fCD4 count or clinical picture. Feline samples gave negative results in the anti-human β2M assay. The assay kits used in this study are not suitable for the determination of the effect of FIV infection on immune activation markers in the cat.