Integrin αIIbβ3-Dependent ERK Signaling Is Regulated by Src and Rho Kinases in Both Leu33 and Pro33 Polymorphic Isoforms.
Acta Haematol. 2016 Dec 07;137(1):44-50
Authors: Huynh KC, Nguyen TH, Pham DC, Nguyen HT, Van Vo T, Gyenes M, Stoldt VR
Platelet integrin αIIbβ3 possesses a Leu/Pro polymorphism at residue 33 (Leu33/HPA-1a or Pro33/HPA-1b). The Pro33 isoform has been suggested to exhibit prothrombotic features. αIIbβ3-expressing CHO (Chinese hamster ovary) cells on immobilized fibrinogen show activation of the MAP kinase family member ERK2, with an enhanced ERK2 activity in Pro33 cells compared to Leu33 cells. In our present work, we examined how the Leu/Pro polymorphism modulates the ERK2 activation stimulated by 2 differently triggered outside-in signalings. We either treated the CHO cells with Mn2+ or allowed them to adhere to fibrinogen. Moreover, we studied which signaling cascades are involved in ERK2 activation. In contrast to immobilized fibrinogen, Mn2+ did not significantly increase ERK2 activation. However, Mn2+ had a synergistic effect on ERK2 phosphorylation when combined with immobilized fibrinogen. Pro33 cells adherent to fibrinogen exhibited a significantly greater ERK2 activity than Leu33 cells in the presence of Mn2+, which peaked after 10 min of adhesion. Our data showed that Src family and rho kinases play a crucial role in the integrin αIIbβ3-dependent outside-in signaling to ERK2.
PMID: 27923225 [PubMed - as supplied by publisher]
Intestinal Pneumatosis Associated with Tuberculosis after Allogeneic Hematopoietic Stem Cell Transplantation.
Acta Haematol. 2016 Dec 07;137(1):51-54
Authors: Venkataramani V, Seif Amir Hosseini A, Schulze MH, Trümper L, Wulf G, Bacher U, Jung W
Pneumatosis intestinalis (PI), defined as intestinal intra- and extramural gas accumulation, is a rare radiographic finding in conditions of intestinal wall damage of varied etiology. Here, we report on a 56-year-old female with multiple myeloma who presented with undulating fever, fluctuating abdominal symptoms, and a distended abdomen 5 months after allogeneic hematopoietic stem cell transplantation (HSCT). Abdominal X-ray and CT scan documented PI with gas accumulation both in the intestinal and colonic bowel walls. Concurrently, thoracic CT revealed mediastinal and bihilar lymphadenopathy associated with bilateral pleural effusions. Microscopy of bronchoalveolar lavage fluid (BALF) revealed acid-fast bacilli, which were identified as Mycobacterium tuberculosis. Tuberculostatic treatment resulted in timely clinical improvement, a complete clearance of the radiological and clinical findings of PI, and the control of the tuberculosis (Tbc), determined by multiple negative BALF results. Taken together, PI occurred as the initial symptom of Tbc in an allogeneic stem cell recipient, achieving complete recovery by tuberculostatic treatment only.
PMID: 27923223 [PubMed - as supplied by publisher]