Macrophage Activation in Follicular Conjunctivitis during the COVID-19 Pandemic

Carla Enrica Gallenga; Martina Maritati; Marco Mura; Francesco Di Virgilio; Pio Conti; Carlo Contini

doi:10.3390/microorganisms11092198

Macrophage Activation in Follicular Conjunctivitis during the COVID-19 Pandemic

Microorganisms. 2023 Aug 31;11(9):2198. doi: 10.3390/microorganisms11092198.

Authors

Carla Enrica Gallenga^{1

2}, Martina Maritati^{3

4}, Marco Mura^{2

5}, Francesco Di Virgilio^{1

6}, Pio Conti^{7

8}, Carlo Contini⁹

Affiliations

¹ Department of Medical Sciences Doctoral Course Molecular Medicine, University of Ferrara, 44121 Ferrara, Italy.
² Ophthalmology Unit, University-Hospital Cona, 44124 Ferrara, Italy.
³ Bone and Infections Lab, Santa Maria Maddalena NH, Occhiobello, 45030 Rovigo, Italy.
⁴ Department of Medical Sciences, Infectious Diseases Unit, University of Ferrara, 44121 Ferrara, Italy.
⁵ Department of Translational Medicine and for the Romagna, Ophthalmology, University of Ferrara, 44121 Ferrara, Italy.
⁶ Department of Medical Sciences, University of Ferrara, 44121 Ferrara, Italy.
⁷ School of Medicine, Immunology, G. D'Annunzio University, Chieti-Pescara, 66100 Chieti, Italy.
⁸ Molecular Pharmacology and Drug Discovery Laboratory, School of Medicine, Tufts University, Boston, MA 02111, USA.
⁹ Department of Medical Sciences, Section Dermatology and Infectious Diseases, University of Ferrara, 44124 Ferrara, Italy.

Abstract

Among the symptoms of SARS-CoV-2, follicular conjunctivitis has become relevant. The conjunctiva acts as an open lymph node, reacting to the viral antigen that binds the epithelial cells, forming follicles of B cells with activated T cells and NK cells on its surface, which, in turn, talk to monocyte-derived inflammatory infected macrophages. Here, the NLRP3 inflammasome is a major driver in releasing pro-inflammatory factors such as IL-6 and caspase-1, leading to follicular conjunctivitis and bulbar congestion, even as isolated signs in the 'asymptomatic' patient.

Keywords: ACE2&TMPRSS2; COVID-19; P2X7R; follicular conjunctivitis; macrophages and activated T cells.

Grants and funding

Supported by institutional funds from the University of Ferrara to F.D.V.