[Pouchitis showed complete response to ustekinumab].

Pouchitis is the most common long-term complication following ileal pouch-anal anastomosis (IPAA) in patients with ulcerative colitis. Although several agents, including probiotics, steroids, and immunomodulators, have been used, the treatment of pouchitis remains challenging. Owing to the proven efficacy of biological therapy in inflammatory bowel disease, there is now growing evidence suggesting the potential benefits of biological therapy in refractory pouchitis. Here, we report the case of a 64-year-old woman with pouchitis due to ulcerative colitis who was successfully treated with ustekinumab (UST). The patient developed ulcerative pancolitis at the age of 35. Total colectomy and IPAA with J-pouch anastomosis were performed when the patient was 47 years old. Ileotomy closure was performed 6 months later. Postoperatively, the patient developed steroid-dependent pouchitis. Three years later, she developed steroid-induced diabetes. The patient has been taking 3mg of steroid for 20 years;therefore, her lifetime total steroid dose was 21g. The patient had over 20 episodes of bloody diarrhea a day. The last pouchoscopy in 20XX-9 revealed inflammatory stenosis with deep ulcerations of the afferent limb just before the ileoanal pouch junction. In July 20XX, when we took over her treatment, the policy of treatment was to withdraw her from steroids. Pouchoscopy revealed a widened but still tight afferent limb through which the scope could easily pass, and the ileoanal pouch still showed erosive ileitis without ulcers. Thiopurine administration and steroid tapering were initiated. Steroid tapering increased the erythrocyte sedimentation rate (ESR). As ESR increased, her arthritis exacerbated. Six months after the end of steroid administration, the patient consented to UST treatment. On April 20XX+1, the patient received her first 260-mg UST infusion. At this point, she experienced 14-15 episodes of muddy bloody stools. She had no abdominal pain;however, she experienced shoulder pain. Gradually, UST affected both pouchitis and arthritis. UST treatment was continued at 90mg subcutaneously every 12 weeks without abdominal pain recurrence. Eight months after the first UST infusion, nonsteroidal anti-inflammatory drugs were no longer necessary for shoulder pain. Follow-up pouchoscopy performed 14 months after UST optimization revealed a normal afferent limb without ulcerations in either segment. Pouchitis remission was maintained for over 2 years.

p24 family Tango(1) at the endoplasmic reticulum exit site to organize cargo exit.

The p24 family of proteins have been regarded as cargo receptors for endoplasmic reticulum (ER) to Golgi transport; however, their precise functions have yet to be revealed. In this issue, Pastor-Pareja and colleagues (https://doi.org/10.1083/jcb.202309045) show that the interaction of these proteins with Tango1 is critical for their localization at the ER exit site (ERES) and efficient transport of secretory proteins in Drosophila.

Small GTPase ActIvitY ANalyzing (SAIYAN) system: A method to detect GTPase activation in living cells.

Small GTPases are essential in various cellular signaling pathways, and detecting their activation within living cells is crucial for understanding cellular processes. The current methods for detecting GTPase activation using fluorescent proteins rely on the interaction between the GTPase and its effector. Consequently, these methods are not applicable to factors, such as Sar1, where the effector also functions as a GTPase-activating protein. Here, we present a novel method, the Small GTPase ActIvitY ANalyzing (SAIYAN) system, for detecting the activation of endogenous small GTPases via fluorescent signals utilizing a split mNeonGreen system. We demonstrated Sar1 activation at the endoplasmic reticulum (ER) exit site and successfully detected its activation state in various cellular conditions. Utilizing the SAIYAN system in collagen-secreting cells, we discovered activated Sar1 localized both at the ER exit sites and ER-Golgi intermediate compartment (ERGIC) regions. Additionally, impaired collagen secretion confined the activated Sar1 at the ER exit sites, implying the importance of Sar1 activation through the ERGIC in collagen secretion.