Insulin-Like Growth Factor Binding Protein, Acid-Labile Subunit Serum Level During the Acute and Convalescent Stage of SARS-CoV-2 Infection Depicted in a Longitudinal Study of 72 Patients During the First Wave of Pandemic.

PURPOSE: Recent discoveries have pointed to the role of IGFALS immunological response to viral challenges, potentially leading to the emergence of a cytokine storm. Here, we investigate if serum IGFALS during the acute response to SARS-CoV-2 will not be likely to accompany immune response during acute phase and convalescence.

PATIENTS AND

METHODS

We recruited patients hospitalized with PCR-confirmed SARS-CoV-2 infection in 2020 and have blood collected after securing consent (tadm), at 48 hours (t48hrs), 7 days (t7d), and after discharge from hospital (tlong). IGFALS and IGF-1 in serum were measured to assess dynamics of the illness and compared against non-specific inflammatory (C-reactive protein, IL-6) markers. Serum titers of IgG against proteins S and N assessed specific viral responses. Serum HMGB-1 was measured to assess level of necrosis. Demographic and clinical data were collected using electronic health records (EHR). Survival was determined at six months from admission.

RESULTS

No difference between serum IGFALS and IGF-1 levels was seen across the studied time points. IGFALSadm showed significant positive correlations with IGFALS48hrs (r2 =0.18; p<0.001), IGFALS7d (r2=0.19; p=0.004), and IGFALSlong (r2 = 0.23; p=0.045). IGFALS correlated negatively with IGF-1 but positively with growth hormone. IGFALSadm showed significant inverse correlations with serum levels of HMGB1adm (r2=0.26; p = <0.001) and t48hr (r2 = 0.27; p<0.001). A significant correlation in the case of IGFALS48hrs and CRP48hrs (r2 = 0.09, p = 0.021), IGFALSlong and CRPlong (r2 = 0.271, p=0.039) was seen. Similar correlations were seen at 48 hours of sampling time for IL-6 (r2 = 0.14, p=0.006). In terms of specific antiviral response, we observed that serum IGFALSadm demonstrated correlation levels of serum IgGadm (r2 = 0.09, p=0.024). A positive correlation was found between length of stay in hospital or ICU and serum IGFALS48hrs.

CONCLUSION

Though IGFALS serum levels did not change significantly during SARS-CoV-2 infection, we observed correlations with markers of tissue destruction, C-reactive protein, IL-6, and length of hospital stay.