Abstract 3689: Jak3 mutations in colorectal neoplasia- Preliminary data on a not so silent minority

As a tumorigenesis model, colorectal cancer is associated with multiple gene mutations accumulating progressively but also has mutations that may alter disease course and provide a therapeutic target. Good examples of this are EGFR and VEGF. In melanoma, PD-1 interactions involving the immunobiome are therapeutically important. We conducted a study to detect potential mutations that might enhance therapy in colorectal cancer guided by expression of p87, a product of innate immune system Paneth cells. Methods: Adnab-9 immunohistochemistry or ELISA was used to define significant p87 Adenoma-associated antigen field effects (FE) in 10 patients with >1cm large high grade dysplastic adenomas (LHiGDA) and 3 with smaller high grade dysplastic adenomas (SHiGDA). We postulated that SHiGDA are not immunologically recognized by host defenses leading to negative outcomes. We used Ion Torrent™ sequencing (ITS) to find mutations in DNA (QiaAmp kit) extracted from 4 normal-appearing colonic segments taken from 1 patient in each group. Novel mutations found on ITS would then be sought using PCR with appropriate primers and subsequent sequencing of the PCR product circulating DNA extracted from available serum samples. These samples were taken from the Large- and SHiGDA groups described above and from 17 patients undergoing colonoscopy for diverse indications. Results: p87 FE were found in 40% of 10 LHiGDA and 0% of 3 SHiGDA patients. The ITS in the 2 representative patients showed unique mutational fields in: KRAS, APC, p53 in the LHiGDA and Jak3, PIK3Ca, p53, APC in the SHiGDA patient, both of whom lacked p87 FE. PCR using the Jak3 primers used in the ITS and subsequent sequencing revealed the same non-synonymous mutation in the serum of a FAP patient after colonic resection and an additional colonic segment of the selected ShiGDA patient but not in his serum. Other Jak3 mutations were found in 1 of 8 LHiGDA, 1 (the selected patient) of 3 SHiGDA, 1 of 7 patients with FAP and 1 of 10 colonoscopy patients with a family history of colorectal cancer with a FE and an untoward outcome. The selected SHiGDA patient subsequently contracted and died of NSCLC adenocarcinoma. The positive LHiGDA and FAP patients had a severely dysplastic anal condyloma and severe pancreatitis, respectively. Overall, the non-synonymous mutation occurring in the non-FAP SHiGDA patient occurred in the absence of p87 FE. Conclusions: In this pilot study we demonstrate the presence of Jak3 mutations likely associated with the lack of p87 expression in patients with high grade dysplastic adenomas and 1 FAP patient. Most of these patients had a clinical course which may have differed from their group members suggesting an altered immune system milieu. If confirmed in SHiGDA and FAP, Jak 3 mutations, associated with the SCID and late onset combined immunodeficiency, may allow for intervention with currently available medications to potentially avert a deleterious clinical outcome.

Citation Format: Martin Tobi, Xiaoping Zhao, Darshana Jhala, Rebecca Rodriguez, Fadi Antaki, Edi Levi, Paula Sochacki, John Lieb, MaryAnn Rambus, Tapan Ganguly, Martin Bluth, Michael J. Lawson. Jak3 mutations in colorectal neoplasia- Preliminary data on a not so silent minority [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3689. doi:10.1158/1538-7445.AM2017-3689

A HEXIM1-AIRE transcriptional counter-balance in trophoblasts regulates maternal-fetal mucosal immunity in pregnancy (MUC7P.755)

Trophoblasts are gatekeepers at maternal-fetal mucosal interface, but trophoblast-derived molecules that initiate and maintain maternal-fetal mucosal immunity are not fully understood. We found that HEXIM1, an inhibitor of P-TEFb essential for eukaryotic RNA Pol II-mediated transcription, is highly expressed in human villous and extravillous trophoblasts. Hexim1-/- mouse placentas exhibit abnormal placental immunity characterized by increased maternal leukocyte and T cell infiltration, a paucity of spiral arteries and reduced placental size. HEXIM1 interacts in trophoblasts with AIRE, a protein critical for central and peripheral immune tolerance, via 7SK snRNA. Such interaction is further dependent on the nuclear localization domains of HEXIM1 and AIRE. Extravillous trophoblasts in human preterm labor with placental inflammation have reduced HEXIM1 and increased AIRE expression. Silencing HEXIM1 in trophoblasts led to increased Treg induction by trophoblasts. Our findings identify trophoblasts as a new type of extrathymic AIRE-expressing immunoregulatory cell, reveal a novel function of epithelial cells in mucosal immune regulation via AIRE-mediated Treg induction, suggest HEXIM1 and AIRE establish a transcriptional counterbalance in trophoblasts to maintain maternal-fetal mucosal immunity in pregnancy by regulating P-TEFb and Pol II, and promote a better understanding of how certain pathogens, such as HIV-1, perturb mucosal homeostasis after hijacking the HEXIM1 machinery.

Defective induction of regulatory B cells by decidua stromal cells underlies the pathogenesis of preterm birth (P3213)

Preterm birth is the leading cause of mortality and morbidity of newborns. Many maternal autoimmune conditions that predispose to preterm birth involve the dysregulation of autoreactive B cells that contribute to disease pathogenesis. Despite the fundamental roles of B cells as effectors and regulators of immunity, their functions in pregnancy are poorly understood. We found that human B cells undergo activation, class switching, memory and plasmacytoid differentiation in the decidua in situ. Preterm decidua harbors increased numbers of total B cells and B-1 cells but diminished numbers of IL-10-producing regulatory B cells in vivo. Furthermore, stromal cells in preterm decidua, as compared to those in term decidua, stimulate increased B cell activation and the differentiation of potentially autoreactive B cells, but are defective in inducing IL-10 expression by B cells. These results demonstrate that preterm birth involves abnormal B cell functions at the maternal-fetal interface, whereby decidua stromal dysfunction engenders unique populations of B cells with increased autoreactivity but diminished regulatory functions, and suggest that regulatory B cells are important for the maintenance of normal pregnancy. These studies provide insights into the functions of B cells at the maternal-fetal interface during pregnancy and inform the design of B cell-targeted therapies to treat preterm birth and other pregnancy complications involving B cell dysfunction.

Mechanism of sophorolipid (SL) suppression of nitric oxide production in models of septic or endotoxic shock. (169.9)

Introduction: Severe sepsis often leads to endotoxic shock and is reported to account for 9% of all deaths in the United States annually. Clinical manifestations of severe sepsis and shock are believed to result from the host’s overwhelming inflammatory reaction to infection and bacterial endotoxins. There is a clear need for new therapeutic approaches and agents based on a better understanding of the physiologic pathways underlying endotoxic shock. Objective: The aim of this project is to determine the mechanism of action of sophorolipids (SL) as novel therapeutic agents to block severe sepsis and shock. We established that SL were protective in vivo when injected following the initiation of endotoxic shock and in vitro when added to macrophage cultures following the addition of LPS. Methods: Cultured macrophages (RAW 264.7) were incubated for 1-5 days with LPS (0-200 ng/ml) and SL (100 ng/ml). Accumulated nitric oxide was measured using Griess reaction. Surface expression of CD14 and TLR4 was determined using specific antibodies (Santa Cruz Biotechnology, immunohistochemistry). Results: LPS induced nitric oxide production was inhibited by 70% in the presence of SL (SL alone had no effect on nitric oxide production). Surface expression of CD14 (macrophage LPS receptor) was also inhibited by 70% in the presence of SL; expression of TLR4 was inhibited by 15%. Conclusions: SL may interfere with binding and intracellular steps in the LPS-mediated gene activation cascade.

Effect of filgrastim (recombinant human granulocyte colony stimulating factor) on IgE responses in human asthma (48.1)

Rationale: The role of peripheral blood progenitor cell mobilization on IgE responses has not been studied. Methods: Distributions of blood lymphocytes (CD4+, CD8+, CD8+CD60+, CD19+, CD23+, CD16/56+, CD25, CD45RA+, CD45RO+, CD34+), and levels of serum immunoglobulins (IgM, IgG, IgA, IgE) were studied in an allergic asthmatic serum IgE+ (181 IU/mL) adult (m/45 y/o) donor undergoing routine stem cell mobilization protocol (American Society of Hematology) before (day -30), during (day 4), and after (1 wk post last dose) filgrastim (subcutaneous, 480 mcg, 2qd) treatment (flow cytometry, nephelometry, UniCAP Total IgE Fluoroenzymeimmunoassay). Results: On day 4 of filgrastim treatment, numbers of CD8+CD60+ T cells and CD23+ blood cells dramatically increased (>2 fold); CD34+ cell numbers also increased. One week after treatment, numbers of these cells decreased to pre-treatment levels. On day 4 of treatment, serum IgE levels decreased (>50%). However, one week after treatment, IgE levels approached pre-treatment levels. Conclusions. Filgrastim treatment transiently increases numbers of CD8+CD60+ T cells known to regulate human IgE responses (Smith-Norowitz, et al., JI, 2008), while also transiently suppressing ongoing IgE responses. These results suggest that filgrastim might be useful in modulating allergic responses.

Long term persistence of IgE anti-hepatitis A virus antibodies in adult serum post vaccination. (113.9)

Rationale: The role of IgE in immunity against Hepatitis A has not been studied. Methods. Serum was obtained from an adult who was vaccinated with Hepatitis A virus (HAV) (Havrix®) in 2005 and again in 2009 and compared with pre vaccination status and natural HAV infection. Serum was assessed for the presence of IgE anti-HAV antibody (modified Immunoblot/ELISA, spectrophotometry) over seven years post vaccination and compared with IgG and IgM virus specific antibodies.. Results. Serum obtained from HAV adult contained IgE anti-virus antibodies which increased over 1.5 years post initial vaccination. In contrast, serum levels of IgE anti-HAV antibodies increased 6 fold two years after 2nd vaccine booster compared with pre-booster levels (1.2OD450 vs 0.21OD450, p<0.05). The rise of IgE anti-HAV levels increased proportionally with time after booster. Interestingly, serum IgE HAV antibody levels seven years post vaccination were comparable to levels of IgE anti-hepatitis antibodies in natural HAV infection (1.2OD450 vs 1.23OD450). Similar patterns were not observed with IgG and IgM anti virus antibodies with respect to consistency and rate of rise. Conclusions. This is the first description of the presence of IgE anti-HAV antibodies, and the first demonstration of its long term persistence serum seven years post vaccination. Understanding the role of IgE anti-virus antibodies may provide insight into vaccine physiology with respect to protection against viral infection.

Immune response profiles after caterpillar exposure (91.3)

Rationale: The role of the immune response to caterpillar exposure is not well described. Methods: Distributions of blood T and B lymphocytes, monocytes (CD1d+), levels of serum Igs(IgM, IgG, IgA, IgE), and cytokines (IFN-γ, IL-4, TNF-α) were studied in an allergic asthmatic serum IgE+ (181 IU/mL) adult who was exposed to the caterpillar, Halysidota harrisii Walsh, 1864. Results: Numbers of CD4+ T cells, CD45 RA+ T cells, CD25 + cells, CD19+ B cells, and CD1d+ monocytes decreased (20-33%) one week post reaction, while CD8+CD60+ T cells and CD23+ cells decreased 48 hrs (33, 74%) post reaction. In contrast, numbers of CD16/56+ NK precursor cells increased (60%) 12 hr, then decreased (65%) 48 hr post reaction; other lymphocyte subsets were unaffected. Serum IgM, IgG and IgA were normal; however, serum IgE levels were elevated 2 hrs post reaction (15%), and returned to pre-exposure levels by 24-48 hrs. High levels of IFN-γ (187-319 pg/mL) and TNF-α (549-749 pg/mL) were detected in serum 24-36 hrs and 3.5-24 hrs post reaction, respectively. In contrast, levels of IL-4 were undetected (<1.0 pg/mL) in serum at all time points. Conclusions. Caterpillar exposure may result in a variety of clinical reactions including increased serum IgE levels, blood CD16/56+ NK precursor cells, and cytokines. Understanding immunomodulation in caterpillar exposure will provide better insight and mechanisms of caterpillar contact and tailor more effective therapeutic intervention.

Lethargy, ulcers, bronchopneumonia and death in two aged female bonnet macaques presumed to be caused by Cercopithicine herpes virus I

Over the course of 4 weeks, two female aged bonnet macaque (Macaca radiata) group-housed females died after the dominant male was removed from the group and the newly dominant male persistently chased, caught and bred all females in the pen. The two aged affected females were observed exhibiting lethargy, dyspnea, with widespread necroulcerative lesions in and around the mouth, muzzle and bridge of their noses. Extensive ulcerative glossitis, necrotic bronchopneumonia with intra-nuclear inclusions and the absence of other evidence is highly suggestive that death was caused by an alphaherpes virus commonly known as herpes B virus. Herpes B virus is a potentially zoonotic disease periodically shed by macaques, which is structurally related to herpes simplex viruses I and II of humans. The emergence of fatal B virus to primates in this pen may have been associated with the combination of age and stress in the affected individuals.

Use of gene expression profiles in cells of peripheral blood to identify new molecular markers of acute pancreatitis

HYPOTHESIS

Blood leukocytes play a major role in mediating local and systemic inflammation during acute pancreatitis. We hypothesize that peripheral blood mononuclear cells (PBMCs) in circulation exhibit unique changes in gene expression and could provide a "reporter" function that reflects the inflammatory response in the pancreas with acute pancreatitis.

DESIGN

To determine specific changes in blood leukocytes during acute pancreatitis, we studied the gene transcription profile in PBMCs in a rat model of experimental pancreatitis (sodium taurocholate). Normal rats, saline controls, and a model of septic shock were used as a controls. Complementary RNA obtained from PBMCs of each group (n = 3 in each group) were applied to Affymetrix rat genome DNA GeneChip arrays. Main Outcome Measure Changes in gene expression.

RESULTS

From the 8799 rat genes analyzed, 140 genes showed unique significant changes in their expression in PBMCs during the acute phase of pancreatitis, but not in sepsis. Among the 140 genes, 57 were up-regulated, while 69 were down-regulated. Platelet-derived growth factor receptor, prostaglandin E(2) receptor, and phospholipase D(1) were among the top up-regulated genes. Others included genes involved in G protein-coupled receptor and transforming growth factor beta-mediated signaling pathways, while genes associated with apoptosis, glucocorticoid receptors, and even the cholecystokinin receptor were down-regulated.

CONCLUSIONS

Microarray analysis in transcriptional profiling of PBMCs showed that genes that are uniquely related to molecular and pancreatic function display differential expression in acute pancreatitis. Profiling genes obtained from an easily accessible source during severe pancreatitis may identify surrogate markers for disease severity.

Case report: Paenibacillus thiaminolyticus: a new cause of human infection, inducing bacteremia in a patient on hemodialysis

Paenibacilli are gram-positive, aerobic bacteria that are related to Bacilli but differ in the DNA encoding their 16S rRNA. Until recently, these organisms were not known to cause human disease. There are now several reports of human infection caused by a few members of this genus, most commonly by P. alvei. We report a human infection in a patient with a permacath for chronic hemodialysis who was found to have bacteremia caused by P. thiaminolyticus, which is an environmental bacterium that has never been found to cause human disease. We identified this bacterium by biochemical tests, cloning, sequencing the genomic DNA encoding its 16S rRNA, growth characteristics, and electron microscopic studies. This constitutes the first report of a human infection caused by this organism.

["I'd like to have a high-dose chemotherapy with stem cell transplantation!"]

Patients with factitious disorders can imitate complex diseases and cause multiple investigations and therapies. The presented patient showed the typical signs and behaviour of this psychiatric disorder. Confrontation may not be helpful in severe cases, whereas a supportive approach might help to avoid further useless and dangerous procedures.