Identifying trajectories of radiographic spinal disease in ankylosing spondylitis: a 15-year follow-up study of the PSOAS cohort

Objectives: Little is known with certainty about the natural history of spinal disease progression in ankylosing spondylitis (AS). Our objective was to discover if there were distinct patterns of change in vertebral involvement over time and to study associated clinical factors. Methods: Data were analysed from the Prospective Study of Outcomes in Ankylosing Spondylitis (PSOAS) observational cohort. All patients met modified New York Criteria for AS and had ≥2 sets of radiographs scored by modified Stoke Ankylosing Spondylitis Spinal Score (mSASSS) by two independent readers between 2002 and 2017. Group-based trajectory modelling (GBTM) was used to classify patients into distinct groups of longitudinal mSASSS considering sociodemographic and clinical covariables. The optimal trajectory model and number of trajectories was selected using Nagin's Bayesian information criterion (BIC). Results: A total of 561 patients with 1618 radiographs were analysed. The optimum number of trajectory groups identified was four (BIC -4062). These groups were subsequently categorized as: non-progressors (204 patients), late-progressors (147 patients), early-progressors (107 patients) and rapid-progressors (103 patients). Baseline predictors associated with higher spinal disease burden groups included: baseline mSASSS, male gender, longer disease duration, elevated CRP and smoking history. In addition, time-varying anti-TNF use per year was associated with decreased mSASSS progression only in the rapid-progressor group. Conclusions: GBTM identified four distinct patterns of spinal disease progression in the PSOAS cohort. Male gender, longer disease duration, elevated CRP and smoking were associated with higher spinal disease groups. Independent confirmation in other AS cohorts is needed to confirm these radiographic patterns.</p

Longitudinal associations between depressive symptoms and clinical factors in ankylosing spondylitis patients: analysis from an observational cohort

Objectives: Although cross-sectional studies have shown that ankylosing spondylitis-specific factors correlate with depressive symptom severity, the association of these factors over time is unresolved. We examined the demographic and clinical factors associated with longitudinal depressive symptom severity in AS patients. Methods: We analyzed sociodemographic, clinical, behavioral and medication data from 991 patients from the Prospective Study of Outcomes in Ankylosing spondylitis cohort, and measured depression severity with the Center for Epidemiological Studies Depression (CES-D) Scale administered at approximately 6-month visit intervals. Multivariable longitudinal negative binomial regression models were conducted using generalized estimating equation modeling to assess the demographic, clinical, and medication-related factors associated with depression severity by CES-D scores over time. Results: The median baseline CES-D score (possible range 0–60) was 10.0 (interquartile range = 5, 17). In longitudinal multivariable analyses, higher CES-D scores were associated with longitudinal smoking, greater functional impairment, greater disease activity, self-reported depression, and poor global health scores. Marital status (e.g., being married) was associated with lower CES-D. Adjusted mean CES-D scores in our model decreased over time, with a significant interaction between time and gender observed. Conclusion: This study identified longitudinal clinical factors such as greater disease activity, greater functional impairment, and poor global health to be associated with longitudinal depression severity. These factors are potentially modifiable and may help manage depressive symptoms in AS

Regulatory B Cell Function Is Suppressed by Smoking and Obesity in H. pylori-Infected Subjects and Is Correlated with Elevated Risk of Gastric Cancer.

Helicobacter pylori infection occurs in more than half of the world's population and is the main cause for gastric cancer. A series of lifestyle and nutritional factors, such as tobacco smoking and obesity, have been found to elevate the risk for cancer development. In this study, we sought to determine the immunological aspects during H. pylori infection and gastric cancer development. We found that B cells from H. pylori-infected patients presented altered composition and function compared to uninfected patients. IL-10-expressing CD24+CD38+ B cells were upregulated in H. pylori-infected patients, contained potent regulatory activity in inhibiting T cell pro-inflammatory cytokine secretion, and responded directly to H. pylori antigen stimulation. Interestingly, in H. pylori-infected smoking subjects and obese subjects, the number of IL-10+ B cells and CD24+CD38+ B cells were reduced compared to H. pylori-infected asymptomatic subjects. Regulatory functions mediated by CD24+CD38+ B cells were also impaired. In addition, gastric cancer positive patients had reduced IL-10-producing B cell frequencies after H. pylori-stimulation. Altogether, these data suggest that in H. pylori-infection, CD24+CD38+ B cell is upregulated and plays a role in suppressing pro-inflammatory responses, possibly through IL-10 production, a feature that was not observed in smoking and obese patients

CD24⁺CD38⁺ B cell responses to bacterial antigen stimulation in different study groups.

<p>Total B cells were isolated from PBMCs by negative selection and then cultured in the absence or presence of heat-killed <i>H</i>. <i>pylori</i> bacterium, together with IL-10 capture beads. After 72h incubation, the secretion of IL-10 in the supernatant was collected by capture beads and measured by luminex assay. The B cells were also harvested for intracellular IL-10 staining. N = 8 for every group. (A) Secreted IL-10 concentration in the supernatant. (B) Percentage of IL-10⁺ cells in CD24⁺CD38⁺ B cells at the end of the 72h incubation. *: P< 0.05. **: P<0.01. ***: P<0.001. (Student’s <i>t</i> test).</p

T cell cytokine secretion after co-culturing with autologous whole B cells, CD24⁺CD38⁺-depleted B cells, or CD24⁺CD38⁺ B cells.

<p>Pure B cells and T cells were isolated from whole PBMCs through magnetic negative selection. Purified B cells were stained with anti-human CD24 and anti-human CD38 antibodies and sent for live cell sorting. The whole B cells, CD24⁺CD38⁺-depleted B cells, or purified CD24⁺CD38⁺ B cells were then co-cultured with autologous T cells in vitro at 1-to-1 ratio for 72h, after which T cells were further separated through magnetic selection into CD4⁺ and CD8⁺ fractions and cultured in the presence of plate-bound anti-CD3 antibody and cytokine capture beads for 6 days. N = 8 for each group. The cytokine productions from (A) CD4⁺ T cells and (B) CD8⁺ T cells were then measured by sensitive luminex assay. *: P< 0.05. **: P<0.01. ***: P<0.001. (Kruskal-Wallis one-way ANOVA and Dunn’s test).</p

Demographic and clinical characteristics of study subjects.

<p>Continuous data were represented as mean (range).</p><p>Past smoker: smoked before but no longer smoking for at least 1 y.</p><p>Current smoker: currently smoking with at least 10 y history.</p><p>N.S.: not significant.</p><p>Demographic and clinical characteristics of study subjects.</p

B cell cytokine expression in H. pylori-infected subjects and in healthy controls.

<p>(A) Percentages of total B cells expressing IL-2, IFN-g, TNF-a, and TGF-b in <i>H</i>. <i>pylori-</i>uninfected (N = 7), <i>H</i>.<i>pylori-</i>infected asymptomatic (N = 8), <i>H</i>. <i>pylori</i>-infected smoking (N = 6), and <i>H</i>. <i>pylori</i>-infected obese (N = 6) subjects under unstimulated (without PMA/ionomycin) condition. (B) Representative dot plots of B cell intracellular cytokine staining without or with PMA/ionomycin stimulation, from an uninfected subject. The cytokine expressions of total B cells minus CD24⁺CD38⁺ B cells (non-CD24⁺CD38⁺ B cells) and that of CD24⁺CD38⁺ B cells were shown separately. (C) Percentages of IL-10-expressing, non-CD24⁺CD38⁺ B cells and CD24⁺CD38⁺ B cells in all study groups, under both unstimulated and PMA/ionomycin stimulated conditions. (D) Numbers of IL-10⁺ B cells in study groups, calculated by the percentage of IL-10-expressing cells in CD24⁺CD38⁺ B cells multiplied by the percentage of CD24⁺CD38⁺ in total B cells (as shown in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0134591#pone.0134591.g001" target="_blank">Fig 1C</a>). *: P< 0.05. **: P<0.01. ***: P<0.001. (Kruskal-Wallis one-way ANOVA and Dunn’s test). For dot plots, 5000 events in each gate were shown.</p

Frequencies of IL-10⁺ B cells and CD24⁺CD38⁺ B cells in study subjects with or without gastric cancer development.

<p>Patients’ gastric cancer status was tracked for 5 years after initial sample collection. (A) The frequencies of IL-10⁺ cells in CD24⁺CD38⁺ B cells after direct <i>H</i>. <i>pylori</i> stimulation in <i>H</i>. <i>pylori</i>-infected smoking subjects and obese subjects (B) The percentages of CD24⁺CD38⁺ B cells in total B cells in <i>H</i>. <i>pylori</i>-infected smoking subjects and obese subjects. N = 8 for every group. *: P< 0.05. (Student’s <i>t</i> test).</p