Wulamujiang Aini

Stromal plasma cells expressing immunoglobulin G4 subclass in non-small cell lung cancer.

Inflammatory cell infiltration in tumor stroma may represent the interaction between the tumor and the immune system. The significance of immunoglobulin (Ig) G4+ plasmacytic infiltration, however, is poorly understood. Here, we analyzed the number of stromal IgG4+ plasma cells and the IgG4/IgG ratio of plasma cells in 294 primary non-small cell lung cancers (NSCLCs) using tissue microarray (TMA) and conventional surgical specimens. In TMA, 35 (12%) cases of NSCLC revealed more than 20 IgG4+ plasma cells per high-power field. In surgical specimens, most (97%) of those IgG4+ plasma cell-enriched cases showed obliterative phlebitis or arteritis, one of the key morphologic features of IgG4-related disease, within or at the periphery of the tumor. Clinically, none of the patients showed symptoms associated with IgG4-related systemic diseases. In patients with stage I squamous cell carcinoma, IgG4-enriched stroma was significantly associated with a favorable prognosis (P = .04). In conclusion, considerable IgG4+ plasma cell infiltration can be seen in a minority of cases of NSCLC and might contribute to prognostic modulation of NSCLC.

Telomere shortening and karyotypic alterations in hepatocytes in long‐term transplanted human liver allografts

The long‐term fate of aged liver allografts in young recipients who received grafts from older donors is unknown. We evaluated graft aging by analyzing hepatocytic telomere length and karyotypic changes. Seventeen pediatric individuals who underwent living‐donor liver transplantation for congenital biliary diseases were selected. At a median of 10.4 years post‐transplant, ten had tolerated grafts with weaned off immunosuppressants, and seven had idiopathic post‐transplantation hepatitis. Fluorescence in situ hybridization was used to evaluate the telomere signal intensity (TI) and karyotypic changes. First, we measured predictive age‐dependent TI decline with regression analysis of donor livers. The mean TI at the earliest (within a year) and latest biopsies was significantly lower than the predicted TI of the studied allografts. With univariate analysis, a higher abnormal karyotype ratio in the donor liver was correlated with development of idiopathic post‐transplantation hepatitis. With multivariate analysis that included clinical parameters, a greater TI decline at the earliest biopsy was correlated with the development of idiopathic post‐transplantation hepatitis. In conclusion, graft aging as measured by TI decline and donor abnormal karyotype ratio was associated with idiopathic post‐transplantation hepatitis of long‐term transplanted liver allografts.

Frequent hepatocyte chimerism in long-term human liver allografts independent of graft outcome.

Microchimerism after liver transplantation is considered to promote graft tolerance or tissue repair, but its significance is controversial. By using multiplex polymerase chain reaction (PCR) of short tandem repeat (STR) loci after laser capture microdissection of hepatocyte nuclei, we compared the proportions of recipient-derived hepatocytes in long-term stable liver allografts and late dysfunctional allografts caused by chronic rejection or idiopathic post-transplantation hepatitis. Through fluorescence in situ hybridization (FISH), we also analyzed the presence of recipient-derived Y-positive hepatocytes in the biopsies of livers transplanted from female donors to male recipients. The study population comprised 24 pediatric liver transplant recipients who survived with the initial graft, whose 10-year protocol biopsy records were available, and who had normal liver function (stable graft, SG; n=13) or a late dysfunctional graft (LDG; n=11) with similar follow-up periods (mean 10.8years in the SG group and 11.2years in the LDG group). STR analysis revealed that hepatocyte chimerism occurred in 7 of 13 (54%) SGs and 5 of 11 (45%) LDGs (p=0.68). The proportion of hepatocyte chimerism was low, with a mean of 3% seen in 2 of 3 female-to-male transplanted livers (one each of SG and LDG). In conclusion, hepatocyte chimerism was a constant event. The extent of engraftment of recipient-derived hepatocytes does not seem to correlate with the degree of hepatic injury in long-term liver allografts.

Histology of intestinal allografts: lymphocyte apoptosis and phagocytosis of lymphocytic apoptotic bodies are diagnostic findings of acute rejection in addition to crypt apoptosis.

Acute rejection of a small-bowel transplant is often difficult to diagnose due to complicated immune responses. The present study aimed to elucidate the specific immune responses involved in intestinal transplant rejection. We correlated immunohistologic findings with an increase in crypt apoptosis, which has been commonly accepted as a criterion for the diagnosis of acute cellular rejection (ACR). Of 8 patients who received an intestinal allograft at Kyoto University Hospital, biopsy specimens from 7 patients were assessed immunohistologically with antibodies against 20 types of lymphocytic antigens including CD3, CD4, CD8, CD79a, CD20, IgG, and T-cell receptor, along with assessment of the patients’ clinical courses. It was revealed that, in addition to apoptotic crypts, T-lymphocyte apoptosis and phagocytosis of apoptotic bodies in the lamina propria of villi were findings of ACR; both were observed in all cases. Immunostaining of the Fas ligand, one of the apoptosis-inducing molecules, was useful for the identification of the apoptotic bodies in the lamina propria of villi. Apoptotic body phagocytosis may be a surrogate diagnostic finding of grafts undergoing ACR.

STAT5A Modulates Chemokine Receptor CCR6 Expression and Enhances Pre-B Cell Growth in a CCL20-Dependent Manner.

Signal transducer and activator of transcription 5A (STAT5A) contributes to B‐cell responses to cytokines through suppressor of cytokine signaling (Socs) genes in innate immunity. However, its direct roles in B‐cell responses to chemokines are poorly understood. In this study, we examined the role of STAT5A in the innate immune response. We found that STAT5A upregulated the transcription of C‐C motif receptor 6 (Ccr6) to induce responses to its ligand, CCL20. STAT5A transcriptional activity proceeded through binding to the interferon‐γ activation site (GAS) element in the CCR6 promoter in the genome of pre‐B cells. High levels of STAT5A and CCR6 increased CCL20‐dependent colony growth of pre‐B cells. In human B‐lymphoblastic lymphoma with inflammation, STAT5A phosphorylation was correlated with CCR6 expression (P > 0.05 compared with that in cases without inflammation). In conclusion, our data supported our hypothesis that STAT5A enhanced the response of pre‐B cells to CCL20 to promote their growth.   J. Cell. Biochem. 117: 2630–2642, 2016.

Abnormal Localization of STK17A in Bile Canaliculi in Liver Allografts: An Early Sign of Chronic Rejection

The biological significance of STK17A, a serine/threonine kinase, in the liver is not known. We analyzed STK17A expression in HepG2 cells and human liver tissue. Accordingly, we investigated whether STK17A could help in identifying earlier changes during the evolution of chronic rejection (CR) after liver transplantation. RT-PCR and immunofluorescence were used to analyze STK17A expression in HepG2 cells. Antibody microarray was performed using human liver samples from CR and healthy donors. Immunohistochemistry was used to verify the clinical utility of STK17A on sequential biopsies for the subsequent development of CR. A novel short isoform of STK17A was found in HepG2 cells. STK17A was localized in the nuclei and bile canaliculi in HepG2 cells and human livers. Microarray of STK17A revealed its decrease in failed liver allografts by CR. During the evolution of CR, the staining pattern of bile canalicular STK17A gradually changed from diffuse linear to focal intermittent. The focal intermittent staining pattern was observed before the definite diagnosis of CR. In conclusion, the present study was the first to find localization of STK17A in normal bile canaliculi. Abnormal expression and localization of STK17A were associated with CR of liver allografts since the early stage of the rejection process.

Reassessment of H&E stained clot specimens and immunohistochemistry of phosphorylated Stat5 for histological diagnosis of MDS/MPN

Summary Few studies have comprehensively analysed histopathological findings of bone marrow clots for diagnosis of haematopoietic cell dysplasia. In particular, a limited number of studies have assessed the use of haematoxylin and eosin (H&E) staining, which is generally considered less informative than May-Giemsa staining. In the current study, the utility of bone marrow clot specimens for diagnosis was examined using H&E staining and immunohistochemistry. Patients with myelodysplastic syndromes (MDS) and myelodysplastic/myeloproliferative neoplasm (MDS/MPN), including chronic myelomonocytic leukaemia (CMML), atypical chronic myeloid leukaemia (aCML) lacking Philadelphia chromosome, and juvenile myelomonocytic leukaemia (JMML), were selected for histological evaluation. H&E stained specimens were advantageous for observation of atypical basophilic staining of the cytoplasm and nucleus related to dysplasia. This finding was significantly supported for both MDS and MDS/MPN (p < 0.05 versus May-Giemsa staining); therefore, we concluded that H&E staining could be used for identification of dysplastic cells. In addition, despite the loss of tissue structure, phosphorylated Stat5 immunostaining was sufficiently useful for the observation of myelodysplastic blasts. Thus, clot specimens are useful for diagnosis of haematopoietic dysplasia by pathologists.

Prevention of Cell Growth by Suppression of Villin Expression in Lithocholic Acid-stimulated HepG2 Cells:

Summary Cholestasis is a condition wherein bile flow is interrupted and lithocholic acid is known to play a key role in causing severe liver injury. In this study, we performed in-depth analysis of the morphological changes in bile canaliculi and the biological role of villin in cholestasis using lithocholic acid-stimulated HepG2 human hepatocarcinoma cells. We confirmed disruption of the bile canaliculi in liver sections from a liver allograft patient with cholestasis. Lithocholic acid caused strong cytotoxicity in HepG2 cells, which was associated with abnormal morphology. Lithocholic acid reduced villin expression, which recovered in the presence of nuclear receptor agonists. Furthermore, villin mRNA expression increased following small interfering RNA (siRNA)-mediated knockdown of the nuclear farnesoid X receptor and pregnane X receptor. Villin knockdown using siRNA caused cell growth arrest in HepG2 cells. The effect of villin-knockdown on whole-genome expression in HepG2 cells was analyzed by DNA microarray. Our data suggest that lithocholic acid caused cell growth arrest by suppressing villin expression via farnesoid X receptor and pregnane X receptor in HepG2 cells.

Telomeres in Liver Transplantation Allografts

Living-donor liver transplant is a life-saving procedure for people with end-stage liver disease that has increased the number of organs available for people on the liver transplant waiting list. Patients often receive grafts from their relatives in living-donor liver transplantation. Maintenance of long-term graft function is important in liver transplant recipients. Livers from older donors have worse graft survival rates in human liver transplantation, and therefore, accurate evaluation of graft aging and senescence is expected to provide critical data for therapeutic intervention in longterm grafts. Many insults, including rejection, can contribute to post-transplant damage. Late post-transplant biopsies frequently show chronic hepatitis of unknown cause, and this can cause late graft dysfunction leading to cirrhosis. Telomere length in chronic hepatitis or cirrhosis is significantly lower than that in normal livers of the same age. Sustained cellular turnover in chronic liver disease accelerates cellular senescence or a crisis because of telomere shortening. Here, we review the mecha‐ nisms involved in post-transplant complications including acute cellular rejection, chronic rejection, and chronic hepatitis of unknown cause by ageing and senescence due to telomere shortening.

The Roles of Invariant NKT Cells in Bowel Immunity — Suppression of Tumor Progression and Rejection of Intestinal Transplants

The roles of natural killer (NK)T cells in intestinal immunity have not been sufficiently investigated. The bowel possesses its own unique mucosal immune system, the gut-associated lymphoepithelial tract (GALT). In this review, we focused on CD1d-independent invariant type NKT (iNKT) cells as modulators of GALT. iNKT cells have a restricted invariant T-cell receptor (TCR) Vα24 chain paired with Vβ11 chain. In addition to T helper (Th)1 cytokines, such as IFN-γ, iNKT cells can produce anti-inflammatory Th2 cytokines, such as interleukin (IL)-4.