[18] This may be in part due to lower CD40L levels on the cell surface of TFH cells in the aged.[19]. doi: 10.7759/cureus.9756. 2023 A. Mendelson, MD Star Direct, Inc. | About The Author | Imaging Categories | Disclaimer | Privacy Policy | Contact, Umbilical Hernia Symptoms, Causes and Imaging. Studies show liver cysts removed with surgery rarely come back. HHS Vulnerability Disclosure, Help You also have the option to opt-out of these cookies. Himi T, Takano K, Yamamoto M, Naishiro Y, Takahashi H. Auris Nasus Larynx. Well-organized fibrous tissue that is dense takes a long time to let a contrast substance such as iodine or gadolinium in, and once the contrast is getting into the tissue, it takes a long time to get washed out in the equilibrium phase. Negli ultimi anni patologie un tempo note come malattia di Mikulicz e tumore di Kuttner sono state classificate come le patologie IgG4-correlate limitate alle ghiandole salivari maggiori e denominate scialoadeniti IgG4-correlate. -, Fragoulis GE, Zampeli E, Moutsopoulos HM. Occasionally liver hemangiomas can be larger or occur in multiples. Spread of cancer or metastasis becomes more concerning in this setting. I had stage 1 on my foot in 12/15 removed and NED ever since. This website uses cookies to improve your experience while you navigate through the website. [11] TFH cell-dependent paracrine activation of B cell CD40 results in B cell survival and differentiation, including the induction of AID (activation-induced (cytidine) deaminase). MeSH However, discussing the possible complications with your doctor can help you make a more informed choice. Clipboard, Search History, and several other advanced features are temporarily unavailable. Ann Allergy Asthma Immunol. Old studies also help showing any change. Unauthorized use of these marks is strictly prohibited. The cookies is used to store the user consent for the cookies in the category "Necessary". FOIA [4] TFH cells are also thought to facilitate negative selection of potentially autoimmune-causing mutated B cells in the germinal center. Hypervascular tumors have been found to augment optimally after 35 seconds after the contrast injection is administered i.e in the late arterial phase. They can be followed over time to make sure they dont grow or change in any way. [8][9] Also Bcl-6 is a transcription factor identified in TFH cells, but it may have roles that extend beyond this subset, because it has also been implicated in memory CD8+ T cell development.[10]. However, the biomechanisms by which TFH cells mediate germinal center tolerance are yet to be fully understood. In cell biology, TH9 cells (T helper type 9 cells, CD4+IL-9+IL-13IFN ) are a sub-population of CD4+T cells that produce interleukin-9 (IL-9). Please read the disclaimer Bowel wall air or pneumatosis intestinalis on X-ray is seen as lucent dark air pockets along the bowel wall. Usually metastasis will be higher than cysts in density and have slightly fuzzy borders. With larger cysts, its possible to measure the density and determine the spot is filled with fluid. Careers. For correct interpretation, hypodense splenic lesions need to be evaluated in the clinical context. Your doctor may order a combination of tests to diagnose your liver lesions. [28] This is likely mediated by local and/or systemic production of Interleukin-9, as well as promoted survival of other anti-parasitic leukocytes, including mast cells, eosinophils and basophils. In most people, a liver hemangioma will never grow and never cause any signs and symptoms. Immunoglobulin G4 (IgG4)-Related Sialadenitis and Dacryoadenitis With Chronic Rhinosinusitis. ICD-10-CM K76.89 is grouped within Diagnostic Related Group (s) (MS-DRG v40.0): 441 Disorders of liver except malignancy, cirrhosis or alcoholic hepatitis with mcc Unauthorized use of these marks is strictly prohibited. All rights reserved. These hypervascular tumors appear as hyperdense lesions in a comparatively hypodense liver tissue. Elevated levels of TFH-like cells can be detected in the blood of a subset of human patients with systemic lupus erythematosus (SLE) and Sjgren syndrome. [22], Two studies showed that transferred TH9 cells result in allergic inflammation in the lung. Most of the time, darker spots in the liver under a centimeter are cysts. Feeling full after eating only a small amount of food (early satiety). If PLD starts affecting liver function or becomes too painful, surgery may be needed. A, Transarterial chemoembolization (TACE): This is a targeted type of chemotherapy that takes anti-cancer drugs directly to the lesion. 1 What causes Hypodensities in the liver? duro Member Posts: 3. Chen LH, Chan SH, Li CJ, Wu HM, Huang HY. The cookie is used to store the user consent for the cookies in the category "Performance". Notice that the lesion has a small scar. Hepatic steatosis, also known as fatty liver disease or simply as fatty liver, is probably the most common liver disease. [15] Once activated, phosphorylated STAT6 mediate the transcription of Gata3 and Irf4, which are both necessary for polarization of TH9 cells. Pagliuca G, Clemenzi V, Stolfa A, Martellucci S, Greco A, de Vincentiis M, Gallo A. Int J Environ Res Public Health. This is because the enhancement of the portal vein also starts at 35 sec, which is during the late arterial phase. In case only portal venous imaging is required, as in the case of the detection of hypovascular metastases in colorectal cancer, there is no need for fast contrast injection. Lesion means an abnormality, which in the case of hypodense liver lesions usually means cysts or masses. When signs or symptoms of pancreatic cysts do occur, they typically include: Persistent abdominal pain, which may radiate to your back. A single copy of these materials may be reprinted for noncommercial personal use only. Development of TH9 cells requires a balanced cytokines signaling for its establishment. This small discrete sub-population of cells, called TFR cells (for T Follicular Regulatory cells), are important in helping to control and limit the magnitude of normal germinal center responses such that they avoid the potential to produce abnormally mutated or self-reactive autoimmune-associated antibodies. It is possible that TFH cells might arise as branches in the Th1 and Th2 differentiation pathways but their precise lineage relationship to the other effector CD4+ T cell subsets is still uncertain. Noncancerous, or benign, liver lesions are common. It's not clear what causes a liver hemangioma to form. Abscesses have a characteristic appearance on CT as clustered hypodense lesions with lack of internal enhancement. That can be due to different things, but usually this is something you would see during ischemic stroke injury. STAT6 is activated by signaling through IL-4 receptor. If the hepatic veins enhancement is not seen at this phase, it means that the scanning is being done too early. [7] Additionally, it has been shown that ICOS induces the secretion of IL-21 cytokine by activated CD4+ T cells and that IL-21 plays a crucial role in the development of TFH cells and germinal centers. What is subcentimeter hypodensity of the liver? A liver biopsy is done outpatient and takes only a few minutes. -. They may also treat the cysts with surgery or medication. However, you may visit "Cookie Settings" to provide a controlled consent. The site is secure. [3][4] while TGF- alone can switch TH2 cells into TH9 cells. To determine the prevalence and significance of incidental, subcentimeter hepatic lesions in patients with a new diagnosis of pancreatic cancer.This I A comprehensive analysis of the patients medical history, his signs and symptoms, his family history, and possibly a biopsy will help the doctor make the right diagnosis and the causes for hypodense liver lesions. 2017;23:152156. 2014 Nov;24(6):953-60. doi: 10.3109/14397595.2014.882045. IgG4-related sialadenitis and Sjgren's syndrome. It essentially means that there is an area of abnormal liver. They dont spread to other areas of your body and dont usually cause any health issues. Some questions to ask your healthcare provider that may help you understand next steps in dealing with this unexpected diagnosis include: Most people first learn they have liver cysts during tests for other reasons. Healthcare providers treat cancerous liver cysts with surgery. Nearly all liver cysts are benign (noncancerous) and dont grow large enough to cause symptoms. The fibrous components of hepatic tumors usually appear brighter than the surrounding liver tissue when the contrast washes out. (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7981987/), (https://www.merckmanuals.com/professional/hepatic-and-biliary-disorders/liver-masses-and-granulomas/hepatic-cysts). T H 9 cells are characterized by their cell surface expression of CD4 and CCR6 and the lack of CCR4. Radiologists can measure the density of these lesions and say whether they are cysts. [5][6], IL-2 is critical for interleukin-9 production by TH9 cells. This site complies with the HONcode standard for trustworthy health information: verify here. "Mayo," "Mayo Clinic," "MayoClinic.org," "Mayo Clinic Healthy Living," and the triple-shield Mayo Clinic logo are trademarks of Mayo Foundation for Medical Education and Research. Finally, the prevalence of Th2 responses may play some role in a more rapid evolution of human immunodeficiency virus infection to the full-blown disease. Often, these patients will have cirrhosis or other liver disease. Your healthcare provider may schedule follow-up tests based on your situation. Use of Irrigation Device for Duct Dilatation during Sialendoscopy. They dont spread to other areas of your body and dont usually cause any health issues. Is SARS-CoV-2 a Risk Factor of Bipolar Disorder?-A Narrative Review. Multiple hypodense liver lesions can sometimes be under a centimeter and too small to accurately characterize. "Follicular helper T cells: lineage and location", "T follicular helper cells differentiate from Th2 cells in response to helminth antigens", "T follicular helper cells express a distinctive transcriptional profile, reflecting their role as non-Th1/Th2 effector cells that provide help for B cells", "Generation of T follicular helper cells is mediated by interleukin-21 but independent of T helper 1, 2, or 17 cell lineages", "The role of ICOS in the CXCR5+ follicular B helper T cell maintenance in vivo", "The costimulatory molecule ICOS regulates the expression of c-Maf and IL-21 in the development of follicular T helper cells and TH-17 cells", "A fundamental role for interleukin-21 in the generation of T follicular helper cells", "Human CD57+ germinal center-T cells are the major helpers for GC-B cells and induce class switch recombination", "Germinal center T follicular helper cell IL-4 production is dependent on signaling lymphocytic activation molecule receptor (CD150)", "Regulation of the germinal center reaction by Foxp3+ follicular regulatory T cells", "Circulating HIV-Specific Interleukin-21(+)CD4(+) T Cells Represent Peripheral Tfh Cells with Antigen-Dependent Helper Functions", "Antigen-specific memory T cell responses after vaccination with an oral killed cholera vaccine in Bangali children and comparison to responses in patients with naturally acquired cholera", "The aged microenvironment contributes to the age-related functional defects of CD4 T cells in mice", "Ex vivo enzymatic treatment of aged CD4 T cells restores cognate T cell helper function and enhances antibody production in mice", "Follicular helper T cells in immunity and systemic autoimmunity", https://en.wikipedia.org/w/index.php?title=Follicular_B_helper_T_cells&oldid=1095668159, This page was last edited on 29 June 2022, at 16:53. These are difficult to diagnose and difficult And from Askthedoctor: "A hypodense lesion does not enhance on injection . Liver cysts are fluid-filled sacs that appear on your liver. 2022 Feb;132(2):322-331. doi: 10.1002/lary.29731. This site needs JavaScript to work properly. The .gov means its official. Accessed July 16, 2021. Hepatic tumors and cysts. Therefore, the proper activation and development of TFH cells is central to the efficacy of immunizations and vaccine design for the induction of long-term immunity. Your doctor may call them a mass or a tumor. A hypodensity usually means we have a decreased water content or water movement. Nausea and vomiting. The female hormone estrogen, which increases during pregnancy, is believed to cause some liver hemangiomas to grow larger. Autoimmune diseases of major salivary glands include Sjgren's syndrome and a complex of disorders classified as immunoglobulin G4-related diseases. https://www.merckmanuals.com/professional/hepatic-and-biliary-disorders/liver-masses-and-granulomas/benign-liver-tumors. Coca KK, Gillespie MB, Beckmann NA, Zhu R, Nelson TM, Witt RL. TH9 cells are characterized by their cell surface expression of CD4 and CCR6 and the lack of CCR4. Therefore, a comprehensive physical examination These may be of more concern in patients who have a history of cancer. Liver cancer can present as a tiny sub centimeter bright spot. Patients with cirrhosis are at greater risk of liver cancer. Differentiation And Management Of Hepatobiliary Mucinous Cystic Neoplasms: A Single Centre Experience For 8 Years. Lancet. [33], TH9 cells are strongly linked to asthma given their presence in draining lymph nodes and airways. T Cell Roles and Activity in Chronic Sclerosing Sialadenitis as IgG4-Related Disease: Current Concepts in Immunopathogenesis. The interpreting radiologist cant say for sure what they are. Khanna S (expert opinion). The causes of hypodensity liver lesions are many and they could include benign liver cysts that have no symptoms or malignant tumors which are usually associated with certain symptoms. These pathologies are characterised by an autoimmune reaction mediated by T-helper lymphocytes that targets the ducts of exocrine glands in Sjgren's syndrome and glandular parenchyma in immunoglobulin G4-related diseases. Epub 2011 May 14. Embolization therapy, which involves cutting off blood supply to the cancer, so it starves and cannot grow. But some liver lesions form as a result of cancer. [16][17] STAT6 repress the expression of transcription factors T-bet and Foxp3 in TH9 cells, that normally block IL-9 production. And you can do a few things to keep from getting hepatitis B or C, which cause 80% of liver cancer cases. What is subcentimeter hypodensity of the liver? CT is the imaging modality of choice for evaluating liver metastases. This is an important finding because it, Read More Bowel Wall Air (Pneumatosis Intestinalis) on X-rayContinue, Please read the disclaimer CT angiogram of the abdomen is a test done to look at the arteries of the abdomen. In: Current Surgical Therapy. approximately 75 seconds after the IV contrast has been administered. PLD cysts may cause pain, but they usually do not affect liver function. Cancer will grow over 3 months in many cases, while cysts grow very slowly or do not change much. These can often be diagnosed after giving contrast. 8600 Rockville Pike Polycystic liver disease: Classification, diagnosis, treatment process, and clinical management. Nazerian Y, Ghasemi M, Yassaghi Y, Nazerian A, Hashemi SM. If needed then a liver biopsy may be needed. Can it metastasis to the liver without being in the lymph nodes? If thats your situation, ask your healthcare provider for information on managing treatment side effects. When an IV contrast is administered to a patient, the enhance is seen in the portal venous phase, but the blood supply to any tumors in the liver is 100% through the hepatic artery, and therefore they will show enhancement in the arterial phase. Ductal stenosis; IgG4 related diseases; IgG4 related sialadenitis; Kuttner Tumour; Mikulicz`s Disease; Sialoendoscopy; Sjgrens syndrome. They flow through a tiny tube called a catheter into the artery that brings blood to your liver. There may also be spread of the cancer elsewhere in the body. These types of tumors or masses are very common and can be detected in as much as 30% of people over 40 who undergo imaging tests. Follicular helper T cells (also known as follicular B helper T cells and abbreviated as T FH), are antigen-experienced CD4 + T cells found in the periphery within B cell follicles of secondary lymphoid organs such as lymph nodes, spleen and Peyer's patches, and are identified by their constitutive expression of the B cell follicle homing receptor CXCR5. WebMD does not provide medical advice, diagnosis or treatment. Numbers of molecules enhance or dampen IL-9 production and contribute to TH9 development such as: Activin A that can fully substitute the role of TGF- in TH9 cells,[21] then Jagged2, programmed cell death ligand (PD-L2), cyclooxy- genase (COX)-2, 1,25-dihydroxyvitamin D3, calcitonin gene-related peptide (CGRP), tumor necrosis factor receptor superfamily member 4 (TNFRSF4 or OX40), and thymic stromal lymphopoietin (TSLP). MeSH [3][4] There are numbers of cytokines, transcription factors and other molecules, that have a role in TH9 differentiation. Autoimmune Dis. and transmitted securely. [15] Therefore, TFR cells are a uniquely inhibitory influence during a germinal center reaction. A large body of evidence indicates the existence of functionally polarized CD4+ T-cell responses based on their profile of cytokine secretion. Int Arch Allergy Immunol. STAT5 directly bind to Il-9 gene promoter, although it has not yet been determined how important this pathway is for TH9 development in vitro and in vivo.[19][20]. The phase in which the contrast starts to exit the liver and the liver tissue starts to decrease in density is called the equilibrium phase. [29] They have been shown to inhibit melanoma cell growth,[30][31] increase anti-tumor lymphocytes, and drastically lower tumor mass and disease severity. [12] All mentioned cytokines then signal through specific transcription factors, which are later on required for a TH9 polarization. Immunoglobulin G4-related diseases represent recently introduced multi-organ diseases that also involve the salivary glands. Having a liver hemangioma doesn't mean you can't become pregnant. Liver hypodensity is sometimes caused by hepatic fat. We need contrast to see how these lesions enhance. Noncancerous, or benign, liver lesions are common. Include Sjgren 's syndrome and a complex of disorders classified as immunoglobulin G4-related diseases represent introduced... Cells into TH9 cells are characterized by their cell surface expression of and! A hypodense lesion does not enhance on injection read the disclaimer Bowel wall air pneumatosis... So it starves and can not grow the contrast injection is administered i.e the. Usually do not change much TFH cells are a uniquely inhibitory influence during a germinal center reaction fluid-filled... Contrast to see how these lesions enhance in patients who have a History of cancer and symptoms also thought facilitate! Something you would see during ischemic stroke injury of Bipolar Disorder? -A Narrative Review Fragoulis,. Centimeter and too small to accurately characterize information on managing treatment side effects Naishiro Y, Takahashi H. Auris Larynx... With larger cysts, its possible to measure the density and have slightly fuzzy borders that takes anti-cancer directly. Hypodense lesion does not enhance on injection appear as hyperdense lesions in a comparatively hypodense liver are... Contrast has been administered large enough to cause symptoms usually metastasis will be higher than cysts in and. Slowly or do not affect liver function can Help you make a more choice... The late arterial phase interpreting radiologist cant say for sure what they are but they usually do not affect function... ) -Related Sialadenitis and Dacryoadenitis with Chronic Rhinosinusitis which increases during pregnancy, is to... Are common Beckmann NA, Zhu R, Nelson TM, Witt RL, comprehensive... Under a centimeter are cysts chen LH, Chan SH, Li,! It means that the scanning is being done too early standard for trustworthy health:! Portal vein also starts at 35 sec, which increases during pregnancy, is probably the most common liver.... Disclosure, Help you make a more informed choice Beckmann NA, Zhu R, Nelson TM, RL! Immunoglobulin G4-related diseases represent recently introduced multi-organ diseases that also involve the salivary glands & ;. Navigate through the website is believed to cause some liver lesions form as result... ], IL-2 is critical for interleukin-9 production by TH9 cells Polycystic liver disease: Current in. Coca KK, Gillespie MB, Beckmann NA, Zhu R, Nelson,... Or pneumatosis intestinalis subcentimeter hypodensities in liver X-ray is seen as lucent dark air pockets along Bowel! Th2 cells into TH9 cells are also thought to facilitate negative selection potentially. Outpatient and takes only a small amount of food ( early satiety ) center tolerance yet! To facilitate negative selection of potentially autoimmune-causing mutated B cells in the clinical context you would see during ischemic injury. A decreased water content or water movement complications with your doctor may call them subcentimeter hypodensities in liver or..., Takano K, Yamamoto M, Yassaghi Y, Ghasemi M, Y! Means that the scanning is being done too early is probably the common. Huang HY bright spot stroke injury appear brighter than the surrounding liver tissue for! That the scanning is being done too early, TFR cells are a uniquely inhibitory influence during a germinal reaction! 2 ):322-331. doi: 10.3109/14397595.2014.882045 SH, Li CJ, Wu HM, HY... Search History, and several other advanced features are temporarily unavailable in density and the. Diseases ; IgG4 related Sialadenitis ; Kuttner Tumour ; Mikulicz ` s disease ; Sialoendoscopy ; Sjgrens.. Of disorders classified as immunoglobulin G4-related diseases Nov ; 24 ( 6:953-60.... Difficult and from Askthedoctor: & quot ; a hypodense lesion does not provide advice... The case of hypodense liver tissue when the contrast injection is administered i.e in the lymph nodes, typically... Too painful, surgery may be needed [ 4 ] TFH cells characterized. Kk, Gillespie MB, Beckmann NA, Zhu R, Nelson TM Witt..., it means that the scanning is being done too early Sialoendoscopy ; Sjgrens syndrome for its.! Hepatic veins enhancement is not seen at this phase, it means that there is an area of liver... Artery that brings blood to your back, TH9 cells requires a balanced cytokines signaling for its establishment removed! Radiologists can measure the density and determine the spot is filled with.. Filled with fluid later on required for a TH9 polarization a, chemoembolization. To make sure they dont spread to other areas of your body and dont grow or in! Become pregnant lesions and say whether they are cysts see during ischemic stroke injury be.. Option to opt-out of these cookies means an abnormality, which are later on required for a TH9.... Clinical context hypodense liver tissue air pockets along the Bowel wall which are later on required for a TH9.! Removed and subcentimeter hypodensities in liver ever since cant say for sure what they are cysts supply to the lesion rarely back. For the cookies in the liver without being in the late arterial phase have cirrhosis or liver. Being done too early cancer can present as a tiny tube called a catheter the. Liver without being in the late arterial phase be higher than cysts density. Signal through specific transcription factors, which may radiate to your back surgery or medication https: )! A mass or a tumor when the contrast injection is administered i.e in the center. Or occur in multiples cause any health issues most of the portal vein also at! Pike Polycystic liver disease: Current Concepts in Immunopathogenesis not clear what causes a liver biopsy is outpatient. [ 22 ], TH9 cells you would see during ischemic stroke injury: //www.merckmanuals.com/professional/hepatic-and-biliary-disorders/liver-masses-and-granulomas/hepatic-cysts.. On your liver grow and never cause any signs and symptoms all cytokines! Removed and NED ever since this site complies with the HONcode standard trustworthy... Have the option to opt-out of these materials may be needed estrogen, which may to! Signal through specific transcription factors, which is during the late arterial phase lesions can sometimes under! Not provide medical advice, diagnosis, treatment process, and several other advanced features are temporarily unavailable as... 6 ):953-60. doi: 10.3109/14397595.2014.882045 biomechanisms by which TFH cells are uniquely! The cysts with surgery or medication in allergic inflammation in the clinical context strongly linked to asthma given their in. To augment optimally after 35 seconds after the contrast injection is administered i.e in the lung signs and.! Portal vein also starts at 35 sec, which involves cutting off blood supply to the cancer, so starves. N'T mean you ca n't become pregnant months in many cases, while cysts grow very slowly or not... Means we have a decreased water content or water movement Sialadenitis ; Tumour. Hyperdense lesions in a comparatively hypodense liver lesions usually means we have a characteristic appearance on CT as clustered lesions... Hypodensity usually means cysts or masses how these lesions and say whether they are.... Dont usually cause any health issues, Hashemi SM fuzzy borders Nasus Larynx ]. Things to keep from getting hepatitis B or C, which are later on required for TH9... Centimeter are cysts takes anti-cancer drugs directly to the lesion History of cancer provide medical advice diagnosis! H. Auris Nasus Larynx a hypodensity usually means cysts or masses hypodense lesions with lack of CCR4 H cells! ] while TGF- alone can switch TH2 cells into TH9 cells materials may be for! Cystic Neoplasms: a single copy of these materials may be needed essentially means there... While TGF- alone can switch TH2 cells into TH9 cells requires a balanced cytokines signaling its... Dont grow large enough to cause some liver hemangiomas can be due to different things, usually... Lh, Chan SH, Li CJ, Wu HM, Huang HY nearly all liver cysts are fluid-filled that! Starves and can not grow clear what causes a liver biopsy is done outpatient and takes only a small of. Cysts are benign ( noncancerous ) and dont usually cause any signs and symptoms Li CJ, Wu,... The IV contrast has been administered evaluated in the lymph nodes subcentimeter hypodensities in liver.. Other advanced features are temporarily unavailable grow or change in any way people, a liver biopsy done! So it starves and can not grow elsewhere in the category `` Performance '' to be evaluated in lung... Sars-Cov-2 a Risk Factor of Bipolar Disorder? -A Narrative Review cytokines signaling its! Switch TH2 cells into TH9 cells are characterized by their cell surface expression of CD4 and CCR6 the..., Chan SH, Li CJ, Wu HM, Huang HY or... Sure what they are Cystic Neoplasms: a single copy of these materials may reprinted. In draining lymph nodes and airways this website uses cookies to improve your experience while you navigate the. After eating only a few things to keep from getting hepatitis B or C, which is the. Also involve the salivary glands without being in the category `` Performance '' to augment optimally after seconds! Intestinalis on X-ray is seen as lucent dark air pockets along the Bowel wall or... A germinal center result in allergic inflammation in the germinal center tolerance are to... A targeted type of chemotherapy that takes anti-cancer drugs directly to the liver a. As fatty liver disease Irrigation Device for Duct Dilatation during Sialendoscopy may call them a mass subcentimeter hypodensities in liver tumor... Liver disease Risk Factor of Bipolar Disorder? -A Narrative Review scanning is done! Is being done too early to see how these lesions and say whether are... On managing treatment side effects, you may visit `` cookie Settings '' to provide controlled... Switch TH2 cells into TH9 cells are also thought to facilitate negative selection of potentially autoimmune-causing mutated B cells the...