Immunological responses in SARS-CoV-2 and HIV co-infection versus SARS-CoV-2 mono-infection: case report of the interplay between SARS-CoV-2 and HIV

Background There is an urgent need to understand the interplay between SARS-CoV-2 and HIV to inform risk-mitigation approaches for HIV-infected individuals.

Objectives We conclude that people living with HIV (PLWH) who are antiretroviral therapy (ART) naïve could be at a greater risk of morbidity or mortality once co-infected with SARS-CoV-2.

Methods Here, we performed extensive immune phenotyping using flow cytometry.

Moreover, to compare the range of values observed in the co-infected case, we have included a larger number of mono-infected cases with SARS-CoV-2.

We also quantified soluble co-inhibitory/co-stimulatory molecules in the plasma of our patients.

Results We noted a robust immune activation characterized by the expansion of CD8^+ T cells expressing co-inhibitory/stimulatory molecules (e.g. PD-1, TIM-3, 2B4, TIGIT, CD39, and ICOS) and activation markers (CD38, CD71, and HLA-DR) in the co-infected case.

We further found that neutrophilia was more pronounced at the expense of lymphopenia in the co-infected case.

In particular, naïve and central memory CD8^+ T cells were scarce as a result of switching to effector and effector memory in the co-infected case.

CD8^+ T cell effector functions such as cytokine production (e.g. TNF-α and IFN-γ) and cytolytic molecules expression (granzyme B and perforin) following anti-CD3/CD28 or the Spike peptide pool stimulation were more prominent in the co-infected case versus the mono-infected case.

We also observed that SARS-CoV-2 alters T cell exhaustion commonly observed in PLWH.

Conclusion These findings imply that inadequate immune reconstitution and/or lack of access to ART could dysregulate immune response against SARS-CoV-2 infection, which can result in poor clinical outcomes in PLWH.

Our study has implications for prioritizing PLWH in the vaccination program/access to ART in resource-constrained settings.