Immune monitoring facilitates the clinical decision in multifocal COVID-19 of a pancreas-kidney transplant patient

Abstract

The optimal management in transplant recipients with coronavirus disease 2019 (COVID-19) remains uncertain. The main concern is the ability of immunosuppressed patients to generate sufficient immunity for antiviral protection. Here, we report on immune monitoring facilitating a successful outcome of severe severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-associated pneumonia, meningoencephalitis, gastroenteritis, and acute kidney and pancreas graft failure in a pancreas-kidney transplant recipient. Despite the very low numbers of circulating B, NK, and T cells identified in follow-up, a strong SARS-CoV-2 reactive T cell response was observed. Importantly, we detected T cells reactive to Spike, Membrane, and Nucleocapsid proteins of SARS-CoV-2 with majority of T cells showing polyfunctional proinflammatory Th1 phenotype at all analyzed time points. Antibodies against Spike protein were also detected with increasing titers in follow-up. Neutralization tests confirmed their antiviral protection. A correlation between cellular and humoral immunity was observed underscoring the specificity of demonstrated data. We conclude that analyzing the kinetics of nonspecific and SARS-CoV-2-reactive cellular and humoral immunity can facilitate the clinical decision on immunosuppression adjustment and allow successful outcome as demonstrated in the current clinical case. Although the antiviral protection of the detected SARS-CoV-2-reactive T cells requires further evaluation, our data prove an ability mounting a strong SARS-CoV-2-reactive T cell response with functional capacity in immunosuppressed patients.

FIGURE 1

Clinical course of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-associated pneumonia, gastroenteritis, meningoencephalitis, kidney and pancreas graft impairment closely accompanied by in-depth immune monitoring. Symptoms, their relative severity and duration, together with accompanying sample monitoring at corresponding visits (V) are presented. The maintenance triple immunosuppressive medication in outpatient setting included tacrolimus (Tac) (trough level 4.6 mg/mL), mycophenolic acid (MPA), and prednisolone. Initially, the patient showed symptoms of coronavirus disease 2019 (COVID-19) pneumonia and gastroenteritis. Because of the very high level of tacrolimus (40 mg/mL) caused by severe diarrhea, tacrolimus medication was paused. Twenty-one days after the onset of the first symptoms, the patient suffered a gradual decrease of renal (creatinine rise from 1.2 to 2.2 mg/dL) and pancreas graft function (insulin-dependence) and was transferred to our transplant center. The symptoms occurred outside of our transplant centers are depicted left from V1 [Color figure can be viewed at wileyonlinelibrary.com]

FIGURE 2

Immune monitoring of circulating immune cells and their activation and differentiation status in clinical follow-up. A, Number of circulating lymphocytes, total CD3⁺, CD3⁺CD4⁺, CD3⁺CD8⁺, and CD25⁺CD127⁻ regulatory T cells (Tregs). The shaded area corresponds to the normal range. B, Number of circulating CD19⁺ B cells and NK cells, defined by CD3⁻CD56⁺. The shaded area corresponds to the normal range. C, Frequency of CD11a⁺⁺ lymphocytes among CD3⁺CD4⁺ and CD3⁺CD8⁺ T cells. D, Frequency of CD57⁺ lymphocytes among CD3⁺CD4⁺ and CD3⁺CD8⁺ T cells. E, Frequency of HLA-DR⁺ lymphocytes among CD3⁺CD4⁺ and CD3⁺CD8⁺ T cells

FIGURE 3

Monitoring of adaptive severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) reactive immunity in clinical follow-up. A, Frequency of M-, N-, or S-protein specific CD4⁺ T cells, defined by expression of CD154⁺ (left panel) and subset by secretion of interferon gamma (IFNγ; panel middle left), interleukin-2 (IL-2; panel middle right), and tumor necrosis factor alpha (TNFα; right panel). B, Frequency of M-, N-, or S-protein specific CD8⁺ T cells, defined by expression of CD137⁺ (left panel) and subset by secretion of IFNγ (right panel). C, Frequency of CD154⁺ bifunctional T cells among CD4⁺ T cells. Bifunctional is defined at expression of any pairwise combination of the cytokines granzyme B (GrzB), IFNγ, IL-2, IL-4, and TNFα. D, Frequency of CD154⁺ trifunctional T cells among CD4⁺ T cells. Bifunctional is defined at expression of any triple combination of the cytokines GrzB, IFNγ, IL-2, IL-4, and TNFα. E, Association between the frequency S-protein specific CD4⁺ T cells, defined by expression of CD154⁺, and S1 specific IgG expressed as the ratio of sample to calibrator [Color figure can be viewed at wileyonlinelibrary.com]