Background: Persistent high risk HPV infection can lead to cervical cancer, the second most common malignant tumor in women worldwide. NK cells play a crucial role against tumors and virus-infected cells through a fine balance between activating and inhibitory receptors. Expression of triggering receptors NKp30, NKp44, NKp46 and NKG2D on NK cells correlates with cytolytic activity against tumor cells, but these receptors have not been studied in cervical cancer and precursor lesions. The aim of the present work was to study NKp30, NKp46, NKG2D, NKp80 and 2B4 expression in NK cells from patients with cervical cancer and precursor lesions, in the context of HPV infection. Methods: NKp30, NKp46, NKG2D, NKp80 and 2B4 expression was analyzed by flow cytometry on NK cells from 59 patients with cervical cancer and squamous intraepithelial lesions. NK cell cytotoxicity was evaluated in a 4 hour CFSE/7-AAD flow cytometry assay. HPV types were identified by PCR assays. Results: We report here for the first time that NK cell-activating receptors NKp30 and NKp46 are significantly down-regulated in cervical cancer and high grade squamous intraepithelial lesion (HGSIL) patients. NCRs down-regulation correlated with low cytolytic activity, HPV-16 infection and clinical stage. NKG2D was also down-regulated in cervical cancer patients. Conclusion: Our results suggest that NKp30, NKp46 and NKG2D down-regulation represent an evasion mechanism associated to low NK cell activity, HPV-16 infection and cervical cancer progression.

Context: Disease Modifying Anti-Rheumatic Drugs (DMARDs) are aimed to interfere with rheumatoid arthritis (RA) progression and reduce the joint damage; however, not all patients respond alike. Killer-cell immunoglobulin-like receptors (KIR) and their ligands, human leucocyte antigen class I (HLA-I), have been associated with RA pathology; therefore, KIR and HLA genes may influence the treatment response. Materials and methods: We evaluated the association of KIR genotype and their ligands HLA-C genes with the response to DMARDs in RA patients. We included 69 patients diagnosed with RA and 82 healthy individuals as the reference group. KIR and HLA-C genotyping was performed using SSP-PCR. RA patients were assessed at baseline and under treatment at 6 and 12 months; subsequently classified as responders and non-responders in each time period. We evaluated the association between DMARD response and genes using statistical analysis by using Fisher exact test with Bonferroni correction; results were regarded as statistically significant at p < 0.05. Results: Significant difference was observed in gene frequencies of patients and the reference group, KIR2DL2 was associated with RA (p = 0.031, OR = 2.119). We also observed an association between KIR2DS2 and the response to methotrexate (MTX), moreover, the combination KIR2DL2+/KIR2DS2+ was more frequent in responders to MTX (p = 0.043). Discussion and conclusions: In our results, responders and non-responders to DMARDs showed KIR2DS2 and KIR2DL2 different gene frequencies, therefore, these genes could be used as response predictors to DMARDs treatment. Thus, these genes were also associated with disease severity, as well as the treatment response possibly by the immunoregulatory function of NK cells.

Introduction. Systemic Sclerosis (SSc) is an autoimmune, inflammatory, and multisystemic disease characterized by the presence of autoantibodies and fibrosis. The pathogenesis involves the interaction between immune system cells such as macrophages, NK cells, T cells, and B cells. Killer-cell Immunoglobulin-like Receptors (KIR) are expressed in NK cells and some T cell subsets that recognize HLA class I molecules as ligands and are involved in regulating the activation and inhibition of these cells. The KIR family consists of 14 genes and two pseudogenes; according to the gene content, the genotype could be AA and Bx. The aim of this study was to evaluate the association between KIR/HLA genes and genotypes with SSc and the clinical characteristics. Methods. We included 50 SSc patients and 90 Control Subjects (CS). Genotyping of KIR, HLA-C, -Bw4, and -A∗03/∗11 was made by SSP-PCR. Results. In SSc patients, a higher frequency of KIR2DL2 (p=0.0007, p′=0.011), KIR2DS4del (p=0.001, p′=0.021), and HLA-C2 (p=0.02, p′=0.09) was found. This is the first study to evaluate the frequency of HLA-A∗03/∗11 in SSc patients, of which a low frequency was found in both groups. Compound genotypes KIR2DL2+/HLA-C1+ or KIR2DL2+/HLA-C2+ have a higher frequency in SSc patients. The Bx genotype was the most frequent and was associated with risk to SSc (p=0.007, OR=3.1, 95% CI=1.4–7.9, p′=0.014). The genotypes with a higher iKIR number than aKIR (iKIR>aKIR) were found in all individuals; genotypes with 7-8 iKIR genes were increased in SSc patients. We do not find an association between the KIR genes with the clinical characteristics. Conclusion. The results suggest that KIR2DL2 and 2DS4del could have a risk role in the development of SSc, but not with clinical manifestations.

Rheumatoid Arthritis (RA) is characterized by joint destruction, chronic inflammation, and autoantibody production. IL-21/IL-21R plays an essential role in the immunopathology of RA. Elevated IL-21 serum levels have been associated with RA and disease activity. Here, we evaluated the association of IL-21/IL-21R polymorphisms and IL-21 serum levels with RA. The study included 275 RA patients and 280 Control subjects (CSs). Single nucleotide polymorphisms IL-21 (rs2055979 and rs2221903) and IL-21R (rs3093301) were genotyped using PCR-RFLP. Clinical activity was evaluated by DAS28-ESR; IL-21 and anti-CCP serum levels were quantified by ELISA. The IL-21 rs2055979 AA genotype was higher in RA patients than in the CS group (p = 0.0216, OR = 1.761, 95% CI = 1.085–2.859); furthermore, RA patients showed anti-CCP elevated levels compared to the CA genotype (p = 0.0296). The IL21R rs3093301 AA genotype was also higher in RA patients than in the CS group (p = 0.0122, OR = 1.965, 95% CI = 1.153–3.348). The AT haplotypes of IL-21 rs2055979 and rs2221903 were more frequent (49%) in the RA group (p = 0.006). IL-21 serum levels were significantly elevated in the RA group, but without an association with IL-21 polymorphisms. In conclusion, IL-21 rs2255979 and IL-21R rs3093301 are associated with a higher risk of RA, and could be a genetic marker. Moreover, the elevated IL-21 levels in RA suggest that IL-21/IL-21R could be a therapeutic target in RA.

Background: Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by autoantibody production and diverse tissue and organ inflammatory affections. Interleukin 21 (IL-21) is implicated in B cell survival, proliferation, differentiation, class switching, and immunoglobulin production; therefore, it is considered a key cytokine in the pathogenesis of SLE. However, its association with disease activity and clinical phenotypes remains unclear. We aimed to evaluate the association of IL-21 levels with the disease activity and clinical phenotypes in patients with SLE. Also, we analyzed the IL21 polymorphisms associated with increased IL-21 levels. Methods: The IL-21 serum levels were determined using the enzyme-linked immunosorbent assay (ELISA) method. The rs2221903 and rs2055979 polymorphisms were assessed in 300 healthy controls (HCs) and 300 patients with SLE by the polymerase chain reaction–restriction fragment length polymorphism (PCR-RFLP) technique. The levels of IL-21 were monitored during follow-up visits in 59 patients with SLE. Results: The patients with SLE showed higher IL-21 levels compared to the HCs. The IL-21 levels did not correlate with Mex-SLEDAI and were not different in patients with inactive, mild–moderate, and severe disease. The IL-21 levels were increased in patients with hematological affection. The ROC curve analysis revealed that the IL-21 levels had good predictive power in discriminating among patients with SLE and HCs. In a follow-up analysis, the levels of IL-21 remained higher in the patients with SLE even when the patients were in remission. Also, the rs2221903 polymorphism was associated with increased IL-21 levels. Conclusions: This study highlights the importance of IL-21 as a key cytokine in SLE. IL-21 levels are higher in patients with SLE and remain increased regardless of disease activity. According to the ROC analysis, IL-21 is a potential biomarker of SLE. Further longitudinal studies are needed to explore the relationship between IL-21 and the clinical phenotypes of SLE.