Table 2.
General features of the viruses putatively involved in systemic lupus erythematosus (SLE) pathogenesis.
| Virus | Family (Type of Genome) |
Proposed Pathogenetic Mechanism in SLE | Therapeutic Approaches | References | |
|---|---|---|---|---|---|
| Epstein–Barr virus (EBV, HHV4) | Herpesviridae (dsDNA, linear) | Molecular mimicry, epitope spreading | Synthetic nucleoside analogs (acyclovir/ganciclovir) effective against lytic infection only, not recommended. Corticosteroids possibly beneficial in patients with airway defects or EBV-induced autoimmune complications. | [36,37,38] | |
| Cytomegalovirus (CMV, HHV5) | Herpesviridae (dsDNA, linear) | Epitope spreading | Synthetic nucleosides (ganciclovir or valganciclovir) drugs of choice for serious infections or treatment of immunocompromised hosts. Nucleotide (cidofovir) or pyrophosphate analogs (foscarnet) second-choice drugs. | [39,40] | |
| Parvovirus B19 (B19V) | Parvoviridae (positive or negative ssDNA, linear) | Molecular mimicry | Supportive care with transfusion (severe anemia, chronic hemolytic disorders). Reduction of immunosuppression. |
[41,42] | |
| Torque Teno Virus (TTV) | Anelloviridae (negative ssDNA, circular) | Molecular mimicry | Not sensitive to current antiviral prophylaxis/therapy. Viral load reduction observed in HIV pts undergoing Highly active antiretroviral therapy (HAART). IFN associated with viral clearance during treatment of coinfecting hepatitis viruses |
[43,44] | |
| Hepatitis C virus (HCV) | Flaviviridae (positive ssRNA) | Epitope spreading | Direct-acting antivirals against viral proteases or polymerases. Ribavirin and IFN as second options. | [45] | |
| Dengue virus (DENV) | Flaviviridae (positive ssRNA) | Epitope spreading | No specific treatment | [46,47] | |
| Retroviruses(RVs) | Exogenous retroviruses (HIV, HTLV) |
Retroviridae (positive diploid ssRNA, linear) | Dysregulation of apoptosis and molecular mimicry (HIV), regulation of CD4 expression (HTLV-1) | Highly active antiretroviral therapy (HAART) (HIV); nucleoside/nucleotide reverse transcriptase inhibitors associated with IFN useful in HTLV-associated haematological diseases, even if prone to relapses. Insufficient evidence to support use of antiretroviral therapy for the treatment of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) | [48,49,50,51] |
| Human Endogenous Retroviruses (HERV) |
Retroviridae (integrated in the host genome) | Molecular mimicry, defects in IFN-stimulatory DNA pathways |
HAART therapy for HIV may also blunt activation of some HERVs | [43,52,53,54] | |