Humoral response against Epstein-Barr virus follows a strain-specific and HIV-driven pattern

Abstract

ABSTRACT Epstein-Barr virus (EBV) is a ubiquitous human gammaherpesvirus causally linked to several malignancies, including lymphomas and solid tumors. Despite its high global prevalence, a comprehensive profile of humoral responses to EBV is yet to be described. Moreover, how HIV-1 co-infection influences this response can reveal new insights into how cancer risk increases in people with HIV-1 (PWH). Here, we employed phage immunoprecipitation and sequencing (PhIP-Seq) using the VirScan phage-display library to map antibody responses against the EBV proteome in 115 adults from sub-Saharan Africa, with and without HIV-1 co-infection (43 HIV-positive and 72 HIV-negative) at peptide-level resolution. We identified EBNA1, EBNA2, EBNA3B, and the viral capsid antigen protein BFRF3 as the most immunodominant EBV proteins. Differential antibody reactivities between EBV Type 1 and Type 2 were observed against EBNA2, with increased antibody recognition near the C-terminal transactivation domain (C-TAD) observed for Type 1. A specific region of EBNA1 containing the nuclear localization sequence (NLS) was the most frequently targeted epitope of the EBV proteome. Our comprehensive and high-resolution analysis identified several immunodominant EBV proteins that are targeted by most individuals regardless of HIV-1 status. HIV-1 co-infected individuals (PWH) had increased antibody recognition against most EBV proteins compared to HIV-uninfected individuals, but the magnitudes of those responses varied across the proteome. Overall, our findings suggest that HIV-1 co-infection alters both the breadth and magnitude of anti-EBV responses, potentially reflecting increased viral reactivation and HIV-driven mechanisms of immunosuppression that may impact the magnitude of antibody responses in EBV. IMPORTANCE This study employs the first comprehensive high-resolution antibody profiling against Epstein-Barr virus (EBV) among healthy adults and people with HIV-1 (PWH). Our results indicated that HIV-1 has a considerable influence on the anti-EBV repertoire that may provide further evidence of how HIV-1 significantly increases the risk of EBV-associated malignancies such as lymphoma. We showed evidence that HIV-1 co-infection leads to higher exposure to viral antigens, likely due to viral reactivation, reflected by a higher percentage of patients with antibodies reactive to the majority of EBV proteins when compared to people without HIV-1. Since PWH are known to be more susceptible to EBV-associated cancers, whether these changes in humoral immune response can be used as prognostic biomarkers for cancer risks should be further investigated with longitudinal studies. This study employs the first comprehensive high-resolution antibody profiling against Epstein-Barr virus (EBV) among healthy adults and people with HIV-1 (PWH). Our results indicated that HIV-1 has a considerable influence on the anti-EBV repertoire that may provide further evidence of how HIV-1 significantly increases the risk of EBV-associated malignancies such as lymphoma. We showed evidence that HIV-1 co-infection leads to higher exposure to viral antigens, likely due to viral reactivation, reflected by a higher percentage of patients with antibodies reactive to the majority of EBV proteins when compared to people without HIV-1. Since PWH are known to be more susceptible to EBV-associated cancers, whether these changes in humoral immune response can be used as prognostic biomarkers for cancer risks should be further investigated with longitudinal studies.