Leukocytes are activated in women with preeclampsia, but the class of leukocyte most likely to cause vascular dysfunction is not known. We hypothesized that neutrophils may be the class of leukocyte most involved in causing this dysfunction because neutrophils are the most abundant of the leukocytes and their numbers increase during pregnancy. In this study we compared vascular infiltration of neutrophils (CD66b) with monocytes/macrophages (CD14) and lymphocytes (CD99) in normal non-pregnant women (NNP), normal pregnant women (NP), and preeclamptic women (PE). There was no significant difference in the infiltration of lymphocytes into the maternal vasculature in PE as compared to NNP or NP. There was significantly more neutrophil infiltration into the systemic vasculature in PE women than in NP and NNP women. Monocytes/macrophages were present in tissue but not in vessels. We speculate that neutrophils are the class of leukocyte that causes the majority of vascular cell dysfunction in preeclampsia.

Les neutrophiles infiltrent la muqueuse colique inflammatoire en maladie de Crohn (CD). Cependant, on ignore l’existence d’une corrélation entre la sévérité endoscopique et la fréquence et/ou l’activation des neutrophiles et autres granulocytes. Une cohorte de 73 patients atteints de CD fut recrutée prospectivement. Les participants furent stratifiés selon la Classification de Montréal ou subdivisés selon le phénotype endoscopique (phénotype typique vs apparence endoscopique « UC-Like »). L’index d’Harvey Bradshaw (HBI) et le Simple Endoscopic score (SES-CD) furent calculés au moment de la coloscopie. La fréquence et l’expression de CD66b et de CD64 sur les granulocytes furent évaluées en cytométrie de flux sur des échantillons sanguins et des biopsies coliques. Le SES-CD corrélait avec l’expression du CD66b sur les neutrophiles coliques et du CD64 sur les neutrophiles circulants en présence de maladie active avec comportement inflammatoire (B1). Les fréquences des neutrophiles et des basophiles mais non des eosinophiles étaient augmentées au sein de la muqueuse inflammatoire, mais la fréquence des neutrophiles coliques n’était corrélée avec le SES-CD uniquement en présence d’un phénotype endoscopique « UC-like ». Deux scores d’activation granulocytaire étaient discriminant entre les individus avec maladie légère et sévère dans l’ensemble de la cohorte avec maladie active. L’activation des granulocytes dans le sang et la muqueuse colique corrèle avec le SES-CD dans des sous-groupes de patients avec une maladie B1, alors que les scores d’activation granulocytaire pourraient être pertinent cliniquement pour évaluer la sévérité de la maladie et possiblement avoir une valeur prognostique parmi les individus avec maladie active. / Neutrophils infiltrate the inflamed colon in Crohn’s disease (CD). However, correlation between endoscopic severity, and frequency and/or activation of neutrophils and other granulocytes like basophils and eosinophils remains to be investigated. A cohort of 73 CD patients was prospectively enrolled according to endoscopic severity and treatment history. Patients with active disease were stratified according to Montreal classification or subdivided into typical CD and UC-like endoscopic features. Harvey Bradshaw Index (HBI) and Simple Endoscopic score (SES-CD) were performed at the time of ileocolonoscopy. Frequency and expression of CD66b and CD64 on granulocytes were assessed in paired blood and colonic biopsies using flow cytometry. SES-CD correlated with neutrophil CD66b expression in mucosa but not blood and conversely, with neutrophil CD64 expression in blood but not mucosa in CD patients with inflammatory (B1) active disease. Frequencies of neutrophils and basophils but not eosinophils, increased in inflamed colon, but only in a subgroup of CD patients presenting “UC-like” endoscopic features were the frequencies of colonic neutrophils correlated with SES-CD. Furthermore, a neutrophil activation score (CD66b X CD64 on neutrophils) and a blood granulocyte score (CD66b on eosinophils X CD64 on neutrophils) discriminated between mild and severe disease in the entire cohort of patients with active disease. Activation of granulocytes in blood and/or mucosa correlated with SES-CD in subgroups of patients with B1 inflammatory disease while granulocyte activation scoring systems may be clinically relevant to evaluate disease severity and predict prognosis in the entire cohort of active disease patients.