P124 Cryptococcus neoformans-and Cryptococcus gattii-specific antibodies vary among children and adults with cryptococcosis and healthy from Colombia

POSTER SESSION 1, SEPTEMBER 21, 2022, 12:30 PM - 1:30 PM: BACKGROUND: Cryptococcus neoformans (Cn), predominantly, and Cryptococcus gattii (Cg) cause cryptococcosis, a life-threatening systemic mycosis of global distribution affecting mainly immunocompromised adults. OBJECTIVES: This study aimed to determine total and specific antibodies against C. neoformans and C. gattii antigens in sera from patients with cryptococcosis and from healthy individuals from Colombia, which will help to elucidate sero-epidemiological variations in the incidence of the disease in the country. METHODS: Sera from child and adult patients with cryptococcosis (n = 109) and sera from healthy children and adults from Colombia (n = 119) were studied. Using ELISA, total and Cn- and Cg-specific levels of immunoglobulin (Ig)G, IgA, and IgM were determined in sera. RESULTS: Total IgG, IgA, and IgM levels were higher in HIV + compared with HIV− patients with cryptococcosis. Specific IgG, IgA, and IgM levels tended to be higher in cryptococcosis patients than in healthy controls and to be higher in adults than in children, with a positive correlation between antibody reactivity and age. All serum immunoglobulins were more reactive against Cn-proteins than Cg-proteins. Including all samples, a positive correlation between total and specific IgG, IgA, and IgM levels was found. CONCLUSIONS: In cryptococcosis patients from Colombia, serum immunoglobulins levels differ depending on HIV status, as reported previously. However, this study shows for the first-time variations in immunoglobulin production among adults and children with cryptococcal disease and between Cn and Cg-protein antigens. The observation of differential antibody reactivity with cryptococcal proteins encourages further studies of the humoral immunity for host defense against cryptococcosis.