Biomarkers of severity and chronification in chikungunya fever: a systematic review and meta-analysis

Cytokine and Chemokine Profiles in Acute Severe Fever with Thrombocytopenia Syndrome and Scrub Typhus in South Korea

In East Asia, severe fever with thrombocytopenia syndrome (SFTS) and scrub typhus, which are common endemic tick- and mite-mediated diseases sharing common clinical manifestations, are becoming public health concerns. However, there are limited data on the comparative immunopathogenesis between the two diseases. We compared the cytokine profiles of SFTS and scrub typhus to further elucidate immune responses that occur during the disease courses. We prospectively enrolled 44 patients with confirmed SFTS and 49 patients with scrub typhus from July 2015 to December 2020. In addition, 10 healthy volunteers were enrolled as healthy controls. A cytometric bead array was used to analyze plasma samples for 16 cytokines. A total of 68 plasma samples, including 31 (45.6%) from patients with SFTS and 37 (54.4%) from patients with scrub typhus, were available for cytokine measurement. There were three cytokine expression patterns: increased levels in both SFTS and scrub typhus (interleukin 6 [IL-6], IL-10, interferon gamma induced protein 10 [IP-10], and granulocyte-macrophage colony-stimulating factor [GM-CSF]), highest levels in SFTS (interferon alpha [IFN-α], IFN-γ, granulocyte-CSF [G-CSF], monocyte chemotactic protein 1 [MCP-1], macrophage inflammatory protein 1α [MIP-1α], and IL-8), and distinct levels in scrub typhus (IL-12p40, tumor necrosis factor alpha [TNFα], IL-1β, regulated on activation and normally T-cell expressed and secreted [RANTES], IL-17A, and vascular endothelial growth factor [VEGF]). Although patients with acute SFTS and scrub typhus exhibited partly shared expression patterns of cytokines related to disease severity, the different profiles of cytokines and chemokines might contribute to higher mortality in SFTS than in scrub typhus. Discrete patterns of helper T cell-related cytokines and VEGF might reflect differences in CD4 T-cell responses and vascular damage between these diseases.

Synergism between chikungunya virus infection and rheumatoid arthritis on cytokine levels: Clinical implications?

Post-chikungunya virus (CHIKV) chronic arthritis shares several immunopathogenic mechanisms with rheumatoid arthritis (RA), which has led to discussions about the probable relationship between the two diseases. Indeed, some studies have suggested a role for CHIKV infection in RA development. However, to the best of our knowledge, the influence of CHIKV on previous RA has not yet been demonstrated. Herein, we analyzed the potential synergism between CHIKV infection and RA on cytokine and chemokine levels. For this, we compared the IL-1β, IL-6, IL-10, IL-17A, CCL2, CXCL8, CXCL9 and CXCL10 levels, in addition to rheumatoid factor (RF) and C-reactive protein (CRP), in patients with post-CHIKV chronic arthritis (named CHIKV group), patients with RA (RA group), and patients with previous RA who were later infected by CHIKV (RA-CHIKV). History of CHIKV infection was confirmed by serology (IgG, ELISA). Cytokines/chemokines were quantified by flow cytometry. RF, CRP, age and sex data were obtained from medical records. IL-1β, IL-6, IL-10 and IL-17A levels were significantly higher in RA-CHIKV compared to the other groups. CXCL8 levels were higher in the CHIKV group than in RA. CXCL9 was higher in CHIKV than in the RA-CHIKV group. CXCL10 was higher in CHIKV than in the other groups. FR levels were higher in RA than in the CHIKV group, and in RA-CHIKV than in CHIKV. No significant difference was observed in CCL2 and CRP, as well as in age and sex. Finally, our findings suggest an interplay between CHIKV infection and RA, which must be analyzed for its possible clinical impact.

Role of cytokines, chemokines, C3a, and mannose-binding lectin in the evolution of the chikungunya infection

The pathogenesis of the severity of chikungunya infection is not yet fully understood.

OBJECTIVE

To assess the role of the cytokines/chemokines and system of complement in the evolution of chikungunya infection.

METHODS

In both acute and chronic phases, we measured the serum levels of 12 cytokines/chemokines and two complement mediators: mannose-binding lectin (MBL) and C3a, in 83 patients with chikungunya infection and ten healthy controls.

RESULTS

During the acute phase, 75.9% of the patients developed musculoskeletal disorders, and in 37.7% of them, these disorders persisted until the chronic phase. In general, patients had higher levels of cytokines than healthy controls, with significant differences for IFN-γ, IL-6, IL-8, IL-10, and MIP-1. Most cytokines exhibited a downward trend during the chronic phase. However, only IL-10, and MIP-1 levels were significantly lower in the chronic phase. Additionally, these levels never decreased to concentrations found in healthy controls. Moreover, MBL levels were significantly higher in the acute phase compared with the chronic phase. C3a levels were significantly higher in patients with musculoskeletal disorder compared with patients without it, in both acute-phase 118.2 (66.5-252.9), and chronic phase 68.5 (64.4-71.3), P < 0.001. Interestingly, C3a levels were significantly higher when patients had a severe disease version. Besides, in the acute phase, C3a levels were higher in patients that suffer arthritis as opposed to when they suffer arthralgia, 194.3 (69.5-282.2), and 70.9 (62.4-198.8), P = 0.013, respectively.

CONCLUSIONS

Our results showed an immunological response that persisted until the chronic phase and the role of the complement system in the severity of the disease.

IL-1Ra and sVCAM-1 in Chikungunya virus infection

Mediators involving in inflammation induction and regulation have been investigated as biomarkers for severe joint pain induced by chikungunya virus (CHIKV) infection. In this report, observational study was conducted to determine levels of an antagonist of interleukin-1 receptor (IL-1Ra) and soluble vascular cell adhesion molecule-1 (sVCAM-1) in CHIKV patients with different disease severity. CHIKV infection patients presented without (n = 199) and with joint pain (n = 262) were included. IL-1Ra and sVCAM-1 levels in patient sera were determined. Levels of sVCAM-1 were strongly and significantly higher in the group of patients with joint pain than in the group without joint pain (p< 0.0001). The levels of both IL-1Ra and sVCAM-1 were not significantly increased with age.

Increased Indoleamine 2,3-Dioxygenase 1 (IDO-1) Activity and Inflammatory Responses during Chikungunya Virus Infection

Chikungunya virus (CHIKV) infection causes intense cytokine/chemokine inflammatory responses and debilitating joint pain. Indoleamine2,3–dioxygenase 1 (IDO-1) is an enzyme that initiates the tryptophan degradation that is important in initial host innate immune defense against infectious pathogens. Besides that, IDO-1 activation acts as a regulatory mechanism to prevent overactive host immune responses. In this study, we evaluated IDO-1 activity and cytokine/chemokine patterns in CHIKV patients. Higher IDO-1 (Kyn/Trp ratio) activation was observed during the early acute phase of CHIKV infection and declined in the chronic phase. Importantly, increased concentrations of Tumor Necrosis Factor-α (TNF-α), Interleukin-6 (IL-6), Interferon γ (IFN-γ), C-C motif chemokine ligand 2/Monocyte Chemoattractant Protein-1 (CCL2/MCP-1) and C-X-C motif chemokine ligand 10/Interferon Protein-10 (CXCL10/IP-10) were found in the acute phase of infection, while C-C motif chemokine ligand 4/Macrophage Inflammatory Protein 1 β (CCL4/MIP-1β) was found at increased concentrations in the chronic phase. Likewise, CHIKV patients with arthritis had significantly higher concentrations of CCL4/MIP-1β compared to patients without arthritis. Taken together, these data demonstrated increased IDO-1 activity, possibly exerting both antiviral effects and regulating exacerbated inflammatory responses. CCL4/MIP-1β may have an important role in the persistent inflammation and arthritic symptoms following chikungunya infection.

Phenotypic and Kinetic Changes of Myeloid Lineage Cells in Innate Response to Chikungunya Infection in Cynomolgus Macaques

Chikungunya (CHIKV) is an emerging worldwide viral threat. The immune response to infection can lead to protection and convalescence or result in long-term sequelae such as arthritis. Early innate immune events during acute infection have been characterized for some cell types, but more must be elucidated with respect to cellular responses of monocytes and other myeloid lineage cells. In addition to their roles in protection and inflammation resolution, monocytes and macrophages are sites for viral replication and may also act as viral reservoirs. These cells are also found in joints postinfection, possibly playing a role in long-term CHIKV-induced pathology. We examined kinetic and phenotypic changes in myeloid lineage cells, including monocytes, in cynomolgus macaques early after experimental infection with CHIKV. We found increased proliferation of monocytes and decreased proliferation of myeloid dendritic cells early during infection, with an accompanying decrease in absolute numbers of both cell types, as well as a simultaneous increase in plasmacytoid dendritic cell number. An increase in CD16 and CD14 was seen along with a decrease in monocyte Human Leukocyte Antigen-DR isotype expression within 3 days of infection, potentially indicating monocyte deactivation. A transient decrease in T cells, B cells, and natural killer cells correlated with lymphocytopenia observed during human infections with CHIKV. CD4⁺ T cell proliferation decreased in blood, indicating relocation of cells to effector sites. These data indicate CHIKV influences proliferation rates and kinetics of myeloid lineage cells early during infection and may prove useful in development of therapeutics and evaluation of infection-induced pathogenesis.

Neopterin and CXCL-10 in Cerebrospinal Fluid as Potential Biomarkers of Neuroinvasive Dengue and Chikungunya

Dengue (DENV) and chikungunya viruses (CHIKV) cause severe neurological complications, sometimes undiagnosed. Therefore, the use of more accessible neuroinflammatory biomarkers can be advantageous considering their diagnostic and prognostic potential for aggravated clinical outcomes. In this study, we aimed to evaluate neopterin and C-X-C motif chemokine ligand 10 (CXCL-10) in cerebrospinal fluid (CSF) for the diagnosis of neuroinvasive DENV and CHIKV. We analyzed the CSF of 66 patients with neurological disorders, comprising 12 neuroinvasive DENV/CHIKV, 20 inflammatory control (viral, bacterial, and fungal meningitis, and autoimmune disorders), and 24 noninflammatory control (cerebrovascular disease, dementia, neoplasm). There was no difference between the concentration of CSF neopterin in the neuroinvasive DENV/CHIKV and control groups. However, there was a significant difference in the CXCL-10 level when comparing the neuroinvasive DENV/CHIKV group and the non-inflammatory control (p < 0.05). Furthermore, we found a linear correlation between neopterin and CXCL-10 CSF levels in the three groups. For the DENV/CHIKV neuroinvasive diagnosis, the ROC curve showed the best cut-off values for CSF neopterin at 11.23 nmol/L (sensitivity of 67% and specificity of 63%), and for CSF CXCL-10 at 156.5 pg/mL (91.7% sensitivity and specificity). These results show that CXCL-10 in CSF represents an accurate neuroinflammatory biomarker that may contribute to neuroinvasive DENV/CHIKV diagnosis.