Enzyme-replacement therapy in mucopolysaccharidosis I

BACKGROUND

Mucopolysaccharidosis I is a lysosomal storage disease caused by a deficiency of the enzyme alpha-L-iduronidase. We evaluated the effect of enzyme-replacement therapy with recombinant human alpha-L-iduronidase in patients with this disorder.

METHODS

We treated 10 patients with mucopolysaccharidosis I (age, 5 to 22 years) with recombinant human alpha-L-iduronidase at a dose of 125,000 U per kilogram of body weight given intravenously once weekly for 52 weeks. The patients were evaluated at base line and at 6, 12, 26, and 52 weeks by detailed clinical examinations, magnetic resonance imaging of the abdomen and brain, echocardiography, range-of-motion measurements, polysomnography, clinical laboratory evaluations, measurements of leukocyte alpha-L-iduronidase activity, and urinary glycosaminoglycan excretion.

RESULTS

Hepatosplenomegaly decreased significantly in all patients, and the size of the liver was normal for body weight and age in eight patients by 26 weeks. The rate of growth in height and weight increased by a mean of 85 and 131 percent, respectively, in the six prepubertal patients. The mean maximal range of motion of shoulder flexion and elbow extension increased significantly. The number of episodes of apnea and hypopnea during sleep decreased 61 percent. New York Heart Association functional class improved by one or two classes in all patients. Urinary glycosaminoglycan excretion decreased after 3 to 4 weeks of treatment; the mean reduction was 63 percent of base-line values. Five patients had transient urticaria during infusions. Serum antibodies to alpha-L-iduronidase were detected in four patients.

CONCLUSIONS

In patients with mucopolysaccharidosis I, treatment with recombinant human alpha-L-iduronidase reduces lysosomal storage in the liver and ameliorates some clinical manifestations of the disease.

CDK inhibitors p18(INK4c) and p27(Kip1) mediate two separate pathways to collaboratively suppress pituitary tumorigenesis

INK4 and CIP/KIP are two distinct families of cyclin-dependent kinase (CDK) inhibitors implicated in mediating a wide range of cell growth control signals. We have created p18(INK4c)-deficient mice. These mice develop gigantism and widespread organomegaly. The pituitary gland, spleen, and thymus are disproportionately enlarged and hyperplastic. T and B lymphocytes develop normally in p18-deficient mice, but both exhibit increased cellularity and a higher proliferative rate upon mitogenic stimulation. Loss of p18, like that of p27, but not other CDK inhibitor genes, leads to a gradual progression from intermediate lobe pituitary hyperplasia in young mice to an adenoma by 10 months of age with a nearly complete penetrance. Mice lacking both p18 and p27, like mice chimeric for Rb deficiency, invariably died from pituitary adenomas by 3 months. Hence, p18 and p27 mediate two separate pathways to collaboratively suppress pituitary tumorigenesis, likely by controlling the function of Rb.

Chronic lymphocytic leukaemia of T-cell origin. Immunological and clinical evaluation in eleven patients

Eleven patients with chronic lymphocytic leukaemia of T-cell origin are reported. The identification of the leukaemic cells was performed with seven different membrane markers for either T or B lymphocytes. The reactivity of the leukaemic T cells with three different heteroantisera to T cells differed from patient to patient but was homogeneous in individual cases. This finding suggests that the leukaemic lymphocytes belonged to a single subset of T cells. These lymphocytes responded to allogeneic cells in some of these patients. In contrast, stimulation by non-specific mitogens was poor in most patients. Two patients were affected with the prolymphocytic type of chronic lymphocytic leukaemia, but a characteristic clinical and haematological pattern was found in nine patients. The blood and marrow infiltration was moderate and the proliferating T lymphocytes had a high content of lysosomal enymes in all patients and cytoplasmic granules in six cases. Other unusual features included massive splenomegaly (five patients), skin lesions (four patients), and major neutropenia (four patients).

Hepatosplenic gammadelta T-cell lymphoma is a rare clinicopathologic entity with poor outcome: report on a series of 21 patients

We report on the characteristics of 21 patients with hepatosplenic gammadelta T-cell lymphoma (HSgammadeltaTCL), an entity recognized since 1994 in the Revised European American Lymphoma (REAL) classification. Median age was 34 years. Patients had splenomegaly (n = 21), hepatomegaly (n = 15), and thrombocytopenia (n = 20). Histopathologic findings were homogeneous and showed the presence of medium-sized lymphoma cells within the sinusoids of splenic red pulp, liver, and bone marrow. Marrow involvement was usually mild but could be demonstrated by phenotyping in all patients. Cells were CD3+CD5-, expressed the gammadelta T-cell receptor, and had a nonactivated cytotoxic cell phenotype (TIA-1+, granzyme B-). Most patients were CD4-/CD8- (16 of 18); CD56+ (15 of 18), expressed the Vdelta1epitope (Vd1+/Vd2-/Vd3-) (9 of 12); and were negative for Epstein-Barr virus (EBV) (18 of 20). Isochromosome arm 7q was documented in 9 of 13 patients. Eight patients had previously undergone kidney transplantation or had a history of systemic lupus, Hodgkin disease, or malaria. Prognosis was poor; median survival time was 16 months, and all but 2 patients ultimately died despite consolidative or salvage high-dose therapy. In conclusion, HSgammadeltaTCL is a disease with distinctive clinical, histopathologic, and phenotypic characteristics. Bone marrow biopsy with combined phenotyping is sufficient for diagnosis, and splenectomy is therefore unwarranted. Current treatment modalities appear to be ineffective in most patients.

Malignant histiocytosis (histiocytic medullary reticulosis). I. Clinicopatholigic study of 29 cases

The clinical records and histologic material from 29 cases of malignant histiocytosis (MH) have been reviewed, as well as autopsy findings in 14 cases. The mean age was 31 years, with a 2.2:1 male to female preponderance. Major physical findings included temperature elevation, lymphadenopathy, hepatomegaly, splenomegaly, and preterminal jaundice. Common laboratory findings were anemia, leukopenia, and thrombocytopenia. The median survival was 6 months, the mean 14 months, and the range from 1 month to 8 years. The histologic features observed in lymph nodes, liver, spleen, and bone marrow have been emphasized, as well as features useful in differential diagnosis. In contrast to our experience with the non-Hodgkin's lymphomas, bone marrow aspiration was superior to biopsy in assessing marrow involvement. Unusual manifestations included soft tissue infiltration in 5 cases; 2 of these patients presented with a soft tissue mass. The distinctive clinical as well as histologic findings warrant recognition and separation of MH from other hematopoietic disorders.

Murine mammary carcinoma 4T1 induces a leukemoid reaction with splenomegaly: association with tumor-derived growth factors

A leukemoid reaction with granulocytosis and splenomegaly has been observed in animals and humans with a variety of tumors. We have employed four color flow cytometry to characterize the leukemoid reaction induced by the transplantable mouse mammary carcinoma 4T1 in female BALB/c mice. Gr-1(+) myeloid cells with the morphology of granulocytes increased in peripheral blood from <15% pre-transplant to nearly 80% of total CD45(+) leukocytes at four weeks post-transplant. Though the granulocyte:lymphocyte ratio increased markedly, the absolute numbers of CD19(+) B lymphocytes, CD4(+) and CD8(+) T lymphocytes, and the CD4/CD8 ratio in peripheral blood did not change significantly. Femurs from tumor-bearing mice showed myeloid hyperplasia of the fatty marrow. There was a notable increase in cells with a Gr-1(dim)/CD11b(bright) immature granulocyte phenotype, and these cells were also found in peripheral blood and spleen. Spleen weights had increased 8.5-fold by four weeks post-tumor transplant, mainly due to granulocytic hyperplasia. Cultured 4T1 tumor cells constitutively expressed mRNA for the myeloid colony-stimulating factors G-CSF and GM-CSF, and IFN-gamma-inducible M-CSF transcripts were also detected. Tumors excised from mice had transcripts for G-CSF and GM-CSF, but only G-CSF protein was found in high levels in serum of tumor-bearing mice. These data demonstrate that 4T1 tumor-bearing mice exhibit a leukemoid reaction that apparently is caused by the production of colony-stimulating factors produced by the tumor. The 4T1 tumor may serve as an excellent model for the study of this reaction.

Mobilization of endothelial and hematopoietic stem and progenitor cells by adenovector-mediated elevation of serum levels of SDF-1, VEGF, and angiopoietin-1

The chemokine stroma-derived factor-1 (SDF-1) is produced within the bone marrow and mediates chemokinesis and chemotaxis on a variety of cell types that express the CXCR4 receptor. SDF-1-responsive cell types include monocytes and macrophages, B and T lymphocytes, platelets and megakaryocytes, and CD34+ cells, including both hematopoietic progenitors and stem cells. We have used intravenous injection of a replication-incompetent adenovector expressing the SDF-1 gene to elevate serum levels of SDF-1 in Balb/c and SCID mice. Within 3 to 5 days there was a marked leukocytosis, predominantly involving monocytes, and a three-fold increase in platelets. In addition, AdSDF-1 mobilized CFU-GM, CFU-s, and cells with long-term repopulating potential. We have identified a bone marrow-derived, circulating endothelial stem cell characterized by expression of the VEGFR2 (Flk-1/KDR). This cell exhibits a chemotactic and chemokinetic response to SDF-1 and VEGF. We have elevated serum levels of VEGF165 using intravenous adenovector gene delivery and compared this to an adenovector expressing angiopoietin-1 alone or in combination with VEGF. VEGF elevation was associated with rapid mobilization of hematopoietic stem and progenitor cells and a population of Flk-1-positive endothelial progenitors. In contrast angiopoietin induced a delayed mobilization of endothelial and hematopoietic progenitors. The combination of VEGF and angiopoietin produced a more prolonged elevation of these progenitors in the circulation with increased proliferation of capillaries and expansion of sinusoidal spaces in the marrow.

A phase 2 trial of combination low-dose thalidomide and prednisone for the treatment of myelofibrosis with myeloid metaplasia

Single-agent thalidomide (THAL) at "conventional" doses (> 100 mg/d) has been evaluated in myelofibrosis with myeloid metaplasia (MMM) based on its antiangiogenic properties and the prominent neoangiogenesis that occurs in MMM. THAL monotherapy at such doses produces approximately a 20% response rate in anemia but is poorly tolerated (an adverse dropout rate of > 50% in 3 months). To improve efficacy and tolerability, we prospectively treated 21 symptomatic patients (hemoglobin level < 10 g/dL or symptomatic splenomegaly) with MMM with low-dose THAL (50 mg/d) along with a 3-month oral prednisone (PRED) taper (beginning at 0.5 mg/kg/d). THAL-PRED was well tolerated in all enrolled patients, with 20 patients (95%) able to complete 3 months of treatment. An objective clinical response was demonstrated in 13 (62%) patients, all improvements in anemia. Among 10 patients who were dependent on erythrocyte transfusions, 7 (70%) improved and 4 (40%) became transfusion independent. Among 8 patients with thrombocytopenia (platelet count < 100 x 10(9)/L), 6 (75%) experienced a 50% or higher increase in their platelet count. In 4 of 21 patients (19%), spleen size decreased by more than 50%. Responses observed were mostly durable after discontinuation of the PRED. The dose of THAL in this study (50 mg/d) was better tolerated than the higher doses used in previous studies. Adverse events associated with corticosteroid therapy were mild and transient. Clinical responses did not correlate with improvements in either intramedullary fibrosis or angiogenesis. THAL-PRED is well tolerated and preliminarily appears to be a promising drug regimen for treating cytopenias in patients with MMM.

Antineoplastic activity of cannabinoids

Lewis lung adenocarcinoma growth was retarded by the oral administration of delta9-tetrahydrocannabinol (delta9-THC), delta8-tetrahydrocannabinol (delta8-THC), and cannabinol (CBN), but not cannabidiol (CBD). Animals treated for 10 consecutive days with delta9-THC, beginning the day after tumor implantation, demonstrated a dose-dependent action of retarded tumor growth. Mice treated for 20 consecutive days with delta8-THC and CBN had reduced primary tumor size. CBD showed no inhibitory effect on tumor growth at 14, 21, or 28 days. Delta9-THC, delta8-THC, and CBN increased the mean survival time (36% at 100 mg/kg, 25% at 200 mg/kg, and 27% at 50 mg/kg, respectively), whereas CBD did not. Delta9-THC administered orally daily until death in doses of 50, 100, or 200 mg/kg did not increase the life-spans of (C57BL/6 times DBA/2)F1 (BDF1) mice hosting the L1210 murine leukemia. However, delta9-THC administered daily for 10 days significantly inhibited Friend leukemia virus-induced splenomegaly by 71% at 200 mg/kg as compared to 90.2% for actinomycin D. Experiments with bone marrow and isolated Lewis lung cells incubated in vitro with delta9-THC and delta8-THC showed a dose-dependent (10(-4)-10(-7)) inhibition (80-20%, respectively) of tritiated thymidine and 14C-uridine uptake into these cells. CBD was active only in high concentrations (10(-4)).

JAK2 V617F mutational status predicts progression to large splenomegaly and leukemic transformation in primary myelofibrosis

Few investigators have evaluated the usefulness of the JAK2 V617F mutation for explaining the phenotypic variations and for predicting the risk of major clinical events in primary myelofibrosis (PMF). In a transversal survey we assayed by allele-specific polymerase chain reaction (PCR) the JAK2 V617F mutational status in 304 patients with PMF. Multiple DNA samples were collected prospectively from 64 patients, and a highly sensitive quantitative PCR was used as a confirmatory test. In a longitudinal prospective study we determined the progression rate to clinically relevant outcomes in 174 patients who had JAK2 mutation determined at diagnosis. JAK2 V617F was identified in 63.4% of patients. None of the V617F-negative patients who were sequentially genotyped progressed to become V617F positive, whereas progression rate from heterozygous to homozygous mutation was 10 per 100 patient-years. JAK2 V617F mutation contributed to hemoglobin, aquagenic pruritus, and platelet count variability, whereas homozygous mutation was independently associated with higher white blood cell count, larger spleen size, and greater need for cytoreductive therapies. Adjusting for conventional risk factors, V617F mutation independently predicted the evolution toward large splenomegaly, need of splenectomy, and leukemic transformation. We conclude that JAK2 V617F genotype should be considered in any future risk stratification of patients with PMF.

Serious adverse events during ruxolitinib treatment discontinuation in patients with myelofibrosis

Ruxolitinib (INCB018424) is a JAK1 and JAK2 inhibitor recently evaluated for the treatment of myelofibrosis (MF) in early- and advanced-phase clinical trials. In 2 recent communications that focused on short-term and long-term ruxolitinib treatment outcome, respectively, the drug was shown to be effective in controlling constitutional symptoms and splenomegaly but was also associated with important adverse effects, including moderate to severe thrombocytopenia and anemia. The most recent of the 2 communications focused on 51 Mayo Clinic patients who participated in the original phase 1/2 ruxolitinib clinical trial and highlighted a high treatment discontinuation rate (92% after a median time of 9.2 months), primarily for loss of treatment benefit but also because of drug-associated adverse effects. The report also discussed the occurrence of sometimes severe withdrawal symptoms during ruxolitinib treatment discontinuation. This "ruxolitinib withdrawal syndrome" was characterized by acute relapse of disease symptoms, accelerated splenomegaly, worsening of cytopenias, and occasional hemodynamic decompensation, including a septic shocklike syndrome. In the current sponsor-independent analysis, we describe the details of these events in 5 severely affected cases (11%) among 47 Mayo Clinic patients with MF in whom ruxolitinib therapy had been discontinued. Our experience calls for full disclosure of the ruxolitinib withdrawal syndrome to patients with MF before initiating ruxolitinib therapy, and treatment discontinuation must be done under close physician supervision and preferably in a tapering schedule.

Role of spleen enlargement in cirrhosis with portal hypertension

The possible relationships between splenomegaly and portal hypertension have been analysed in patients with cirrhosis. In this condition, splenomegaly is not only caused by portal congestion, but it is mainly due to tissue hyperplasia and fibrosis. The increase in spleen size is followed by an increase in splenic blood flow, which participates in portal hypertension actively congesting the portal system.

Expansion of CD19(hi)CD21(lo/neg) B cells in common variable immunodeficiency (CVID) patients with autoimmune cytopenia

Common variable immunodeficiency (CVID) is characterized by a severe hypogammaglobulinemia. While the clinical picture is dominated by recurrent respiratory and gastrointestinal infections, a subgroup of up to 30% of the patients develops additional autoimmune phenomena, including thrombocytopenia and autoimmune hemolytic anemia. So far no classification allowed a prediction of the coincidence of immunodeficiency and autoimmunity. Here, we propose the size of the peripheral CD19(hi)CD2(lo/neg) B cell pool as a marker for CVID patients with autoimmune cytopenia and splenomegaly. Interestingly similar B cell populations are also found in patients with SLE and may not only be an epiphenomenon of the disease.

High incidence of malaria in alpha-thalassaemic children

The alpha+-thalassaemias are the commonest known human genetic disorders, affecting up to 80 per cent of some populations. Although there is good evidence from both epidemiological and clinical studies that these gene frequencies reflect selection by, and protection from, malaria, the mechanism is unknown. We have studied the epidemiology of malaria in childhood on the southwestern Pacific island of Espiritu Santo in Vanuatu and here we report that, paradoxically, both the incidence of uncomplicated malaria and the prevalence of splenomegaly, an index of malaria infection, are significantly higher in young children with alpha+-thalassaemia than in normal children. Furthermore, this effect is most marked in the youngest children and for the non-lethal parasite Plasmodium vivax. The alpha+-thalassaemias may have been selected for their ability beneficially to increase susceptibility to P. vivax, which, by acting as a natural vaccine in this community, induces limited cross-species protection against subsequent severe P. falciparum malaria.

Spleen stiffness measurement using Fibroscan for the noninvasive assessment of esophageal varices in liver cirrhosis patients

BACKGROUND AND AIM

Splenomegaly in a common finding in liver cirrhosis that should determine changes in the spleen's density because of portal and splenic congestion and/or because of tissue hyperplasia and fibrosis. These changes might be quantified by elastography, so the aim of the study was to investigate whether spleen stiffness measured by transient elastography varies as liver disease progresses and whether this would be a suitable method for the noninvasive evaluation of the presence of esophageal varices.

PATIENTS AND METHODS

One hundred and ninety-one patients (135 liver cirrhosis, 39 chronic hepatitis and 17 healthy controls) were evaluated by transient elastography for measurements of spleen and liver stiffness. Cirrhotic patients also underwent upper endoscopy for the diagnosis of esophageal varices.

RESULTS

Spleen stiffness showed higher values in liver cirrhosis patients as compared with chronic hepatitis and with controls: 60.96 vs 34.49 vs 22.01 KPa (P<0.0001). In the case of liver cirrhosis, spleen stiffness was significantly higher in patients with varices as compared with those without (63.69 vs 47.78 KPa, P<0.0001), 52.5 KPa being the best cut-off value, with an area under the receiver operating characteristic of 0.74. Using both liver and spleen stiffness measurement we correctly predicted the presence of esophageal varices with 89.95% diagnostic accuracy.

CONCLUSION

Spleen stiffness can be assessed using transient elastography, its value increasing as the liver disease progresses. In liver cirrhosis patients spleen stiffness can predict the presence, but not the grade of esophageal varices. Esophageal varices' presence can be better predicted if both spleen and liver stiffness measurements are used.

Prosthetic valve endocarditis

From January 1963 until January 1974, 45 patients had prosthetic valve endocarditis. Symptoms of prosthetic valve endocarditis developed within 2 months after operation (early onset) in 16 patients (36%) and more than 2 months after operation (late onset) in 29 patients (64%). Overall mortality among the 45 patients was 56% (88% among those with early onset and 40% among those with late onset). Medical therapy alone was curative in 60% of the surviving patients. Combined medical and surgical therapy was curative in 40% of the survivors. The most frequent isolates in the early-onset group were Staphylococcus aureus (44%) and Gram-negative bacilli (38%); associated mortality was 86% and 83%, respectively. The most frequent isolates in the late-onset group were viridans streptococci (41%) and Gram-negative bacilli (31%); the mortality was 25% and 22% respectively. Suggestions are offered for operative antimicrobial prophylaxis and for medical and surgical treatment of prosthetic valve endocarditis. Prompt surgical replacement of an infected prosthesis is necessary when medical therapy fails.

Morphologic properties of neoplastic mast cells: delineation of stages of maturation and implication for cytological grading of mastocytosis

In the present study, cytological properties of bone marrow mast cells (MC) were analyzed and correlated with clinical parameters in 69 patients with systemic mastocytosis (SM). Based on cytomorphological features, four distinct cell types were recorded: (i) typical tissue MC (round cells, well granulated, round central nuclei); (ii) atypical MC exhibiting elongated cytoplasmic extensions, oval nuclei with excentric position, and a hypogranulated cytoplasm with focal granule accumulation ('atypical MC type I'); (iii) atypical MC with bi- or multilobed nuclei ('atypical MC type II'); and (iv) metachromatically granulated blast-like cells. In the majority of cases with SM, the percentage of MC in bone marrow (bm) smears was less than 5% (of all nucleated bm cells), and the predominant types were typical MC or atypical MC type I. In a smaller group of patients, the percentage of MC was greater than 5% and a significant subset of MC (>or=10%) were classified as 'metachromatic blasts' and/or atypical MC type II. These patients had a significantly shorter survival (P<0.05) and most of them were found to lack UP-like skin lesions. A percentage of MC>or=20% was invariably associated with the diagnosis 'mast cell leukemia'. Multivariate analysis confirmed the prognostic value of the cytology in SM and identified the percentage of MC (of all nucleated bm cells) as an independent prognostic variable. These data suggest that cytomorphological assessment of bm MC in SM is an important diagnostic approach that may help to delineate between variants of the disease.

Long-term safety of treatment with recombinant human granulocyte colony-stimulating factor (r-metHuG-CSF) in patients with severe congenital neutropenias

Congenital neutropenias include a heterogenous group of diseases characterized by a decrease in circulating neutrophils. In phase I/II/III studies in patients with severe congenital and cyclic neutropenia, treatment with recombinant human granulocyte colony-stimulating factor (r-metHuG-CSF) resulted in a rise in the absolute neutrophil counts (ANC) and a reduction in infections. We report the effects of long-term safety of subcutaneous r-metHuG-CSF administration in 54 patients (congenital n = 44. cyclic n = 10) treated for 4-6 years. A sustained ANC response was seen in 40/44 severe congenital neutropenia patients and 10/10 cyclic neutropenia patients. Two patients required an increase of > 25% in dose to maintain a clinical response; one patient became refractory to therapy. A significant decrease in the incidence of severe infections and the need for intravenous antibiotics was noted. Significant adverse events noted which may or may not be related to therapy included: osteopenia (n = 15), splenomegaly (n = 12), hypersplenism (n = 1), vasculitis (n = 2), glomerulonephritis (n = 1), BM fibrosis (n = 2), MDS/leukaemia (n = 3), and transient inverted chromosome 5q with excess blasts (n = 1). R-metHuG-CSF has been well tolerated in the majority of patients and resulted in a long-term improvement in their clinical status.

Ae2a,b-deficient mice develop antimitochondrial antibodies and other features resembling primary biliary cirrhosis

BACKGROUND & AIMS

Cl(-)/HCO(3)(-) anion exchanger 2 (AE2) is involved in intracellular pH (pH(i)) regulation and transepithelial acid-base transport, including secretin-stimulated biliary bicarbonate excretion. AE2 gene expression was found to be reduced in liver biopsy specimens and blood mononuclear cells from patients with primary biliary cirrhosis (PBC), a disease characterized by chronic nonsuppurative cholangitis associated with antimitochondrial antibodies (AMA) and other autoimmune phenomena. In mice with widespread Ae2 gene disruption, we previously reported altered spermiogenesis and reduced gastric acid secretion. We now describe the hepatobiliary and immunologic changes observed in these Ae2(a.b)-deficient mice.

METHODS

In this murine model, splenocyte pH(i) and T-cell populations were studied by flow cytometry. CD3-stimulated cytokine secretion was estimated using cytokine arrays. AMA were evaluated by immunoblotting and proteomics. Hepatobiliary changes were assessed by immunohistopathology, flow cytometry, and serum biochemistry. Cholangiocyte gene expression was analyzed by real-time polymerase chain reaction.

RESULTS

Ae2(a,b)(-/-) mice exhibit splenomegaly, elevated pH(i) in splenocytes, increased production of interleukin-12p70 and interferon gamma, expanded CD8(+) T-cell population, and under represented CD4(+)FoxP3(+)/regulatory T cells. Most Ae2(a,b)(-/-) mice tested positively for AMA, showing increased serum levels of immunoglobulin M and G, and liver-specific alkaline phosphatase. About one third of Ae2(a,b)(-/-) mice had extensive portal inflammation with CD8(+) and CD4(+) T lymphocytes surrounding damaged bile ducts. Cholangiocytes isolated from Ae2(a,b)(-/-) mice showed gene expression changes compatible with oxidative stress and increased antigen presentation.

CONCLUSIONS

Ae2 deficiency alters pH(i) homeostasis in immunocytes and gene expression profile in cholangiocytes, leading to immunologic and hepatobiliary changes that resemble PBC.