CCL19 and CCR7 Expression, Signaling Pathways, and Adjuvant Functions in Viral Infection and Prevention

Abstract

Chemokine (C–C motif) ligand 19 (CCL19) is a critical regulator of the induction of T cell activation, immune tolerance, and inflammatory responses during continuous immune surveillance, homeostasis, and development. Migration of CC-chemokine receptor 7 (CCR7)-expressing cells to secondary lymphoid organs is a crucial step in the onset of adaptive immunity, which is initiated by a complex interaction between CCR7 and its cognate ligands. Recent advances in knowledge regarding the response of the CCL19-CCR7 axis to viral infections have elucidated the complex network of interplay among the invading virus, target cells and host immune responses. Viruses use various strategies to evade or delay the cytokine response, gaining additional time to replicate in the host. In this review, we summarize the impacts of CCL19 and CCR7 expression on the regulation of viral pathogenesis with an emphasis on the corresponding signaling pathways and adjuvant mechanisms. We present and discuss the expression, signaling adaptor proteins and effects of CCL19 and CCR7 as these molecules differentially impact different viral infections and viral life cycles in host homeostatic strategies. The underlying mechanisms discussed in this review may assist in the design of novel agents to modulate chemokine activity for viral prevention.

The Atlantic Salmon Gill Transcriptome Response in a Natural Outbreak of Salmon Gill Pox Virus Infection Reveals New Biomarkers of Gill Pathology and Suppression of Mucosal Defense

“…In contrast to CCL20 suppression, CCL19 is strongly induced in SGPVD gills. CCL19 is involved in T-cell recruitment during viral infection, and binds to the CCR7 receptor which is expressed on immune cells and cancer cells ( 52 ). CCL19 is also reported to promote AICD of T-cells, an effect associated with increased expression of FAS ligand (FASL/TNFSF6) ( 53 ).…”

The cytokine storm in COVID-19: Further advances in our understanding the role of specific chemokines involved

“…CCL19 is a pro-inflammatory chemokine that belongs to the CC chemokine family. The binding of CCL19 to its receptor CCR7, mediates several migratory events in adaptive immunity following antigen encounter by immunocytes [ 58 ].The binding of CCL19 to CCR7 receptor is crucial for the recruitment of antigen presenting dendritic cells and naïve T-cells to secondary lymphoid organs [ 59 ]. CCL19 also plays an important role in rheumatic and autoimmune diseases being overexpressed in autoimmune responses and in chronic inflammatory conditions [ 58 ].…”

“…The binding of CCL19 to its receptor CCR7, mediates several migratory events in adaptive immunity following antigen encounter by immunocytes [ 58 ].The binding of CCL19 to CCR7 receptor is crucial for the recruitment of antigen presenting dendritic cells and naïve T-cells to secondary lymphoid organs [ 59 ]. CCL19 also plays an important role in rheumatic and autoimmune diseases being overexpressed in autoimmune responses and in chronic inflammatory conditions [ 58 ]. Regarding the SARS-COV-2 infection scenario, there are limited data about the role of CCL19, of note Balnis et al found that high levels of CCL19 chemokine in patients’ serum significantly correlated with outcome and greater mortality in a cohort of patients on mechanical ventilation infected by SASR-COV2 developing ARDS.…”

Does the Use of the “Proseek® Multiplex Oncology I Panel” on Peritoneal Fluid Allow a Better Insight in the Pathophysiology of Endometriosis, and in Particular Deep-Infiltrating Endometriosis?

“…promotes migration of certain cells of the immune system, in particular antigen-presenting dendritic cells [ 59 ]…”