Natural killer cells and type II interferon in Ro/SSA and La/SSB autoantibody-exposed newborns at risk of congenital heart block

Annals of the Rheumatic Diseases collection on pregnancy 2018-2023: observational data-driven knowledge

Pregnancy can be an exciting time but for those living with rheumatic musculoskeletal diseases (RMDs), it can also be a time fraught with concern, including what effect pregnancy will have on the underlying RMD and what effect the RMD may have on the pregnancy and the baby, including the effects of medications. Generating an evidence base in pregnancy is challenging. Few interventional trials of medications in RMD pregnancies have ever been conducted, often for concerns of safety for both the mother and the child. Therefore, observational research remains important for informing clinical practice and helping women with RMDs make decisions regarding their health preconception and during pregnancy. The Annals of the Rheumatic Diseases (ARD) continues to publish important research on pregnancy in RMDs to increase the evidence base on this subject. Here we present an overview of papers published on this topic between January 2018 and December 2023. Our focus includes papers on pregnancy and RMD outcome, the effects of drug exposure, fetal outcomes as well as fertility.

Home monitoring of fetal heart rhythm: Lived experiences of women with anti-SSA/Ro52 autoantibodies and their co-parents

OBJECTIVE

The aim of this study was to explore the parents' experiences of home monitoring of the fetal heart rhythm. Women with anti-SSA/Ro52 autoantibodies carry a 2%-3% risk of giving birth to a child with congenital heart block (CHB), following transplacental transfer and antibody-mediated inflammation in the fetal conduction system during 18th to 24th gestational week. Early detection and subsequent treatment have been reported to decrease morbidity and mortality. Therefore, home monitoring of the fetal heart rhythm by Doppler has been offered at our fetal cardiology center. This study was undertaken to explore the lived experience of the routine.

METHODS

Participants were recruited from a single fetal cardiology center. Consecutive sampling was used. The inclusion criteria were women with SSA/Ro52 antibodies who had undergone Doppler examinations within the last two and a half years at the hospital and had monitored the fetal heartbeat at home. A semi-structured questionnaire was created, and the participants were interviewed individually. The interviews were transcribed verbatim and analyzed according to qualitative content analysis.

RESULTS

The overall theme was defined as "walking on thin ice," with six underlying categories: reality, different strategies, gain and loss, healthcare providers, underlying tension, and conducting the examinations again, all with a focus on how to handle the home monitoring during the risk period.

CONCLUSION

Both the mother and the co-parent expressed confidence in their own abilities and that the monitoring provided them with the advantage of growing a bond with the expected child. However, all the participants described a feeling of underlying tension during the risk period. The results show that home monitoring is not experienced as complicated or a burden for the parents-to-be and should be considered a vital part of the chain of care for mothers at risk for giving birth to a child with CHB. However, explaining the teamwork between the different caregivers, for the patients involved, their areas of expertise, and how they collaborate with the patient continues to be a pedagogic challenge and should be developed further.

Impact of Sjögren's syndrome on maternal and fetal outcomes following pregnancy: a systematic review and meta-analysis of studies published between years 2007-2022

OBJECTIVE

To show the impact of Sjögren's syndrome (SS) on maternal and fetal outcomes following pregnancy.

METHODS

We performed a literature search based on PubMed, Web of science, Wan fang, China National Knowledge Infrastructure and ProQuest databases from 1 January 2007 to 6 November 2022. Grading of Recommendations, Assessment, Development, and Evaluations approach was used to assess the certainty of the evidence. Systematic reviews and meta-analyses were performed using RevMan 5.3 software. Pooled odds ratio (OR) and 95% confidence interval (CI) were calculated using a random-effect, generic inverse variance method of DerSimonian and Laird. Trial sequential analyses were performed by TSA 0.9.

RESULTS

Nine studies with 2341 patients and 2472 pregnancies with SS were included in our analysis. This current analysis showed pregnancy hypertension and preeclampsia/eclampsia to be significantly higher in pregnant women with SS compared to pregnant women without SS (OR: 1.65, 95% CI: 1.04-2.63; P = 0.03), (OR: 2.06, 95% CI: 1.16-3.65; P = 0.01) respectively. Cesarean section, thromboembolic disease, premature rupture of membranes, and spontaneous abortion were also significantly higher in the SS women with OR: 2.07, 95% CI: 1.48-2.88; P < 0.0001, OR: 9.45, 95% CI: 1.99-44.87; P = 0.005, OR: 1.36, 95% CI: 1.13-1.64; P = 0.001, OR: 9.30, 95% CI: 4.13-20.93; P < 0.00001, respectively. Significantly higher premature births were observed with infants who were born from SS mothers (OR: 2.19, 95% CI: 1.54-3.12; P < 0.0001). Infants defined as 'small for gestational age/intrauterine growth restriction' and 'weighing < 2500 g' were also significantly higher in patients suffering from SS (OR: 2.26, 95% CI: 1.38-3.70; P = 0.001), (OR: 3.84, 95% CI: 1.39-10.61; P = 0.009) respectively. In addition, live birth significantly favored infants who were born from mothers without SS (OR: 21.53, 95% CI: 8.36-55.44; P < 0.00001). Subgroup analysis by sample size revealed that pregnancy hypertension risk has significantly increased in small cohort (OR: 2.74, 95%CI: 1.45-5.18), and a slight increase was found in population-based studies (OR: 1.14, 95%CI: 0.91-1.43). In both small cohorts and population-based researches, cesarean section was significantly higher in SS (OR: 2.13, 95% CI: 1.29, 3.52; OR: 1.85, 95% CI: 1.29-2.64, respectively). The number of infants with intrauterine growth restriction did not grow in the population-based researches (OR: 2.07, 95%CI: 0.92-4.66) although there has been an increase in small reports (OR: 2.53, 95%CI: 1.16-5.51). Subgroup analysis was conducted on the basis of study location (not Asian vs. Asian countries) indicated that cesarean section was significantly higher in SS in both countries (OR: 1.69, 95% CI: 1.31-2.18; OR: 3.37, 95% CI: 2.39-4.77, respectively).

CONCLUSION

This meta-analysis has shown SS to have a high impact on maternal and fetal outcomes following pregnancy.

Autoimmune congenital heart block: a case report and review of the literature related to pathogenesis and pregnancy management

Autoimmune congenital heart block (ACHB) is a passively acquired immune-mediated disease characterized by the presence of maternal antibodies against components of the Ro/SSA and La/SSB ribonucleoprotein complex that mainly affects the cardiac conducting system. ACHB occurs in 2% of women with positive anti-Ro/SSA and anti-La/SSB antibodies and causes a high risk of intrauterine fetal death, neonatal mortality, and long-term sequelae. In this review, we first describe a case of ACHB to provide preliminary knowledge. Then, we discuss the possible pathogenic mechanisms of ACHB; summarize the pregnancy management of patients with positive anti-Ro/SSA and anti-La/SSB antibodies and/or rheumatic diseases, the prevention of ACHB, and the treatment of ACHB fetuses; and propose routine screening of these antibodies for the general population. Careful follow-up, which consists of monitoring the fetal heart rate, is feasible and reassuring for pregnant women with positive anti-Ro/SSA and/or anti-La/SSB antibodies to lower the risk of ACHB in fetuses. Moreover, maternal administration of hydroxychloroquine may be useful in preventing ACHB in pregnant women with anti-Ro/SSA and/or anti-La/SSB antibodies.

MICa/b-dependent activation of natural killer cells by CD64+ inflammatory type 2 dendritic cells contributes to autoimmunity

Primary Sjögren's syndrome (pSS) is an inflammatory autoimmune disorder largely mediated by type I and II interferon (IFN). The potential contribution of innate immune cells, such as natural killer (NK) cells and dendritic cells (DC), to the pSS pathology remains understudied. Here, we identified an enriched CD16+ CD56hi NK cell subset associated with higher cytotoxic function, as well as elevated proportions of inflammatory CD64+ conventional dendritic cell (cDC2) subtype that expresses increased levels of MICa/b, the ligand for the activating receptor NKG2D, in pSS individuals. Circulating cDC2 from pSS patients efficiently induced activation of cytotoxic NK cells ex vivo and were found in proximity to CD56+ NK cells in salivary glands (SG) from pSS patients. Interestingly, transcriptional activation of IFN signatures associated with the RIG-I/DDX60 pathway, IFN I receptor, and its target genes regulate the expression of NKG2D ligands on cDC2 from pSS patients. Finally, increased proportions of CD64hi RAE-1+ cDC2 and NKG2D+ CD11b+ CD27+ NK cells were present in vivo in the SG after poly I:C injection. Our study provides novel insight into the contribution and interplay of NK and cDC2 in pSS pathology and identifies new potential therapy targets.

Uncovering potential new biomarkers and immune infiltration characteristics in primary Sjögren's syndrome by integrated bioinformatics analysis

Primary Sjögren's syndrome (pSS) is known as autoimmune disease characterized by damage to endocrine glands, such as the salivary and lacrimal glands. This study aimed to identify potential biomarkers for pSS using integrated bioinformatics analysis and explore the relationship between differentially expressed genes (DEGs) and immune infiltration. Three pSS datasets (GSE7451, GSE23117, and GSE40611) from the gene expression omnibus database were integrated. All the datasets were processed in R (version 4.0.3). A total of 16 immune cells and 13 immune functions were obtained. The top immune cell and immune function were "activated" dendritic cells and major histocompatibility complex class I. Correlation analysis showed the top correlation among 16 immune cells were B cells and tumor infiltrating lymphocytes, check-point and T cell co-stimulation, respectively. In comparisons of immune score, "activated" dendritic cells (.657 vs 594, P < .001), B cells (.492 vs 434, P = .004), macrophages (.631 vs 601, P = .010), inflammation-promoting (.545 vs 478, P < .001), Type I interferon Reponse (.728 vs 625, P < .001) and so on were higher in pSS than control group. In correlation analysis, the up-regulation of interferon induced protein with tetratricopeptide repeats 1 gene was strongly correlated with Type I interferon response with a correlation coefficient of .87. The receiver operating characteristic curve of 5 genes showed that the area under curve was.891. In the verification model, the area under curve was.881. In addition, disease ontology analysis supported the association between DEGs and pSS. In summary, pSS has a variety of DEGs in immune infiltration, which is worthy of the attention from clinicians.

Increased Concentrations of Circulating Soluble MHC Class I-Related Chain A (sMICA) and sMICB and Modulation of Plasma Membrane MICA Expression: Potential Mechanisms and Correlation With Natural Killer Cell Activity in Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is a severe autoimmune disease of unknown etiology. The major histocompatibility complex (MHC) class I-related chain A (MICA) and B (MICB) are stress-inducible cell surface molecules. MICA and MICB label malfunctioning cells for their recognition by cytotoxic lymphocytes such as natural killer (NK) cells. Alterations in this recognition have been found in SLE. MICA/MICB can be shed from the cell surface, subsequently acting either as a soluble decoy receptor (sMICA/sMICB) or in CD4⁺ T-cell expansion. Conversely, NK cells are frequently defective in SLE and lower NK cell numbers have been reported in patients with active SLE. However, these cells are also thought to exert regulatory functions and to prevent autoimmunity. We therefore investigated whether, and how, plasma membrane and soluble MICA/B are modulated in SLE and whether they influence NK cell activity, in order to better understand how MICA/B may participate in disease development. We report significantly elevated concentrations of circulating sMICA/B in SLE patients compared with healthy individuals or a control patient group. In SLE patients, sMICA concentrations were significantly higher in patients positive for anti-SSB and anti-RNP autoantibodies. In order to study the mechanism and the potential source of sMICA, we analyzed circulating sMICA concentration in Behcet patients before and after interferon (IFN)-α therapy: no modulation was observed, suggesting that IFN-α is not intrinsically crucial for sMICA release in vivo. We also show that monocytes and neutrophils stimulated in vitro with cytokines or extracellular chromatin up-regulate plasma membrane MICA expression, without releasing sMICA. Importantly, in peripheral blood mononuclear cells from healthy individuals stimulated in vitro by cell-free chromatin, NK cells up-regulate CD69 and CD107 in a monocyte-dependent manner and at least partly via MICA-NKG2D interaction, whereas NK cells were exhausted in SLE patients. In conclusion, sMICA concentrations are elevated in SLE patients, whereas plasma membrane MICA is up-regulated in response to some lupus stimuli and triggers NK cell activation. Those results suggest the requirement for a tight control in vivo and highlight the complex role of the MICA/sMICA system in SLE.