Thymus transplantation as immunotherapy for the enhancement and/or correction of T cell function.

The thymus is where T cells, among the most important immune cells involved in biological defense and homeostasis, are produced and developed. The thymus plays an important role in the defense against infection and cancer as well as the prevention of autoimmune diseases. However, the thymus gland atrophies with age, which might have pathological functions, and in some circumstances, there is a congenital defect in the thymus. These can be the cause of many diseases related to the dysregulation of T cell functions. Thus, the enhancement and/or normalization of thymic function may lead to protection against and treatment of a wide variety of diseases. Therefore, thymus transplantation is considered a strong candidate for permanent treatment. The status and issues related to thymus transplantation for possible immunotherapy are discussed although it is still at an early stage of development.

Monomorphic T-cell post-transplant lymphoproliferative disorder with features of HHV8-negative primary effusion lymphoma: an autopsy case and review of the literature.

A 67-year-old man underwent renal transplantation in his twenties. He developed refractory pleural effusion, with many large lymphocytes with severe atypia and mitosis in the effusion, indicating malignant lymphoma. He finally died of respiratory failure. An autopsy revealed atypical lymphocytes positive for CD3, CD4, and CD30 and negative for CD8, CD20, PAX5, human herpesvirus (HHV) 8, and Epstein-Barr virus-encoded small RNAs by immunohistochemistry and in situ hybridization. Atypical lymphocytes also had T-cell receptor gene rearrangements Jß2, Jγ2, and Jδ1 and chromosomal aberrations der(8)t(1;8)(q21;p21), add(13)(q12), add(14)(q32), and add(16)(q12-13). A few atypical lymphocytes were present at other sites. We finally diagnosed this case as monomorphic T-cell post-transplant lymphoproliferative disorder with features of HHV8-negative primary effusion lymphoma. A literature review only identified six cases (four HHV8-negative, two HHV8-positive) of effusion lymphoma of T-cell type, including the present case. Interestingly, about half of HHV8-negative and HHV8-positive cases had a history of renal transplantation in their twenties. All cases showed tumor CD30 expression, whereas CD4 and CD8 expressions were inconsistent. These findings indicated that this lymphoma may be associated with post-transplant lymphoproliferative disorder by renal transplantation at a young age, although further cases need to be analyzed.

[Repair of Metachronous Inguinal Metastasis from Resected Gastric Cancer by Transabdominal Preperitoneal (TAPP) Technique-A Case Report].

A 68-year-old male patient underwent laparoscopic pyloric gastrectomy(D2)in October 2015 for gastric cancer, pStage ⅠB. In August 2017, a 3 cm large abdominal wall metastasis in the left lateral abdomen was removed. In September 2019, a 2 cm tumor was found in the left inguinal region. The left inguinal area was repaired using mesh with the TAPP technique because of a large abdominal wall defect centered on the inner inguinal ring. Three and a half years after the resection, he is continuing complete response(CR)with nivolumab therapy.

Sudden-onset gallbladder rupture due to Ceftriaxone-associated pseudolithiasis in a patient with acquired hemophilia A.

We herein report a 76-year-old man with acquired hemophilia A (AHA) who developed gallbladder rupture due to Ceftriaxone (CTRX)-associated pseudolithiasis. The patient was admitted for an examination of systemic subcutaneous bleeding. A blood test showed a prolonged activated partial thromboplastin time and sequentially revealed low factor VIII activity (<1%) and a high factor VIII inhibitor level of 143 BU/mL. The patient was thus diagnosed with AHA. After admission, he developed a high-grade fever and was administered intravenous CTRX, considering the possibility of psoas abscess or cellulitis. Although his high-grade fever was improved, computed tomography incidentally showed a high-density lesion in the gallbladder, suggestive of CTRX-associated pseudolithiasis without clinical symptoms. Despite cessation of CTRX, the pseudolithiasis never disappeared, and the patient suddenly died after rapid progression of abdominal bloating. An autopsy revealed that the gallbladder was severely swollen and had ruptured with hemorrhaging because of hemorrhagic cholecystitis, caused by CTRX-associated pseudolithiasis with AHA. Our case demonstrated that CTRX-associated pseudocholelithiasis can unexpectedly induce gallbladder hemorrhaging and rupture in a patient with a bleeding diathesis, including AHA. CTRX-associated pseudocholelithiasis can cause a fatal outcome in patients with a bleeding disorder, even if CTRX is ceased as soon as pseudocholelithiasis is detected.

Induction of γδT cells from HSC-enriched BMCs co-cultured with iPSC-derived thymic epithelial cells.

T cells bearing γδ antigen receptors have been investigated as potential treatments for several diseases, including malignant tumours. However, the clinical application of γδT cells has been hampered by their relatively low abundance in vivo and the technical difficulty of inducing their differentiation from hematopoietic stem cells (HSCs) in vitro. Here, we describe a novel method for generating mouse γδT cells by co-culturing HSC-enriched bone marrow cells (HSC-eBMCs) with induced thymic epithelial cells (iTECs) derived from induced pluripotent stem cells (iPSCs). We used BMCs from CD45.1 congenic C57BL/6 mice to distinguish them from iPSCs, which expressed CD45.2. We showed that HSC-eBMCs and iTECs cultured with IL-2 + IL-7 for up to 21 days induced CD45.1+ γδT cells that expressed a broad repertoire of Vγ and Vδ T-cell receptors. Notably, the induced lymphocytes contained few or no αßT cells, NK1.1+ natural killer cells, or B220+ B cells. Adoptive transfer of the induced γδT cells to leukemia-bearing mice significantly reduced tumour growth and prolonged mouse survival with no obvious side effects, such as tumorigenesis and autoimmune diseases. This new method suggests that it could also be used to produce human γδT cells for clinical applications.

Transverse colonic volvulus due to mesenteric fibromatosis: a case report.

BACKGROUND: Colonic volvulus, a condition in which a colonic segment partially twists around its base, is the third leading cause of large bowel obstruction after colonic neoplasms and diverticular disease. However, volvulus of the transverse colon is the rarest type of large intestinal volvulus. Moreover, the occurrence of transverse colonic volvulus secondary to a benign tumor originating from outside the intestine has never been reported. We hereby report a case of transverse colonic volvulus caused by mesenteric fibromatosis. CASE PRESENTATION: A 53-year-old female with a history of rheumatoid arthritis and thyroid tumor presented with abdominal pain for 1 day. Abdominal computed tomography revealed intestinal torsion at the hepatic flexure. Twisted and obstructed mucosa of the transverse colon was observed during colonoscopy, but no tumor invasion of the mucosal surface was detected. A solid mass of a mesenteric origin with involvement of the transverse colon was observed during surgery. The mass was diagnosed surgically as transverse colonic volvulus induced by a mesenteric tumor. Hence, the patient underwent a right hemicolectomy. Histopathological results indicated mesenteric desmoid-type fibromatosis. The postoperative recovery was uneventful, and the patient was discharged 8 days after surgery. CONCLUSIONS: Although mesenteric fibromatosis is rare, this disease should be considered when managing transverse colonic volvulus resulting from nonmucosal tumors.

The role of CD5 expression in thymic carcinoma: possible mechanism for interaction with CD5+ lymphoid stroma (microenvironment).

AIMS: Most thymic carcinomas express the lymphocyte marker CD5 aberrantly. This study was performed to examine the role of the self-reactive CD5 antigen in thymic carcinoma. METHODS AND RESULTS: We examined CD5 expression in thymic carcinoma in relation to the lymphoid stroma. All cases of thymic carcinoma examined expressed CD5. A number of CD5(+) lymphocytes were also present in the stroma of thymic carcinoma. The CD5(+) tumour areas were predominantly in contact with the lymphoid stroma, and the expression level was significantly lower in tumour cells than lymphocytes. Although p53 and Bcl-2 expression levels were significantly higher in thymic carcinoma than normal thymic epithelial cells (TECs), they did not differ between CD5(+) and CD5(-) areas. E-cadherin expression in thymic carcinoma was comparable with that of normal TECs, and it also did not differ between these areas. In contrast, both Ki-67 index and mitotic activity were significantly higher in thymic carcinoma than normal TECs, and they were significantly higher in CD5(+) than CD5(-) areas. CONCLUSIONS: CD5 may be induced by interaction with CD5(+) lymphoid stroma, and may be related to tumour proliferation. CD5 induction may also be a significant and/or specific effect of the tumour microenvironment of the thymus.

Positive C4d staining of the portal vein endothelium in the liver of patients with biliary atresia: a role of humoral immunity in ongoing liver fibrosis.

PURPOSE: This study aimed to clarify the role of complement activation in fibrogenesis in BA. METHODS: In total, 27 paraffin-embedded liver biopsy samples were immunohistochemically analyzed using C4d polyclonal antibody, vascular cell adhesion molecule-1 (VCAM-1), and CD45. The liver samples were obtained from 25 patients during Kasai operation, and two additional specimens were obtained from 2 patients by needle biopsy later at the time of liver function deterioration. The degree of liver fibrosis was histologically graded 1-3. RESULTS: Among the 25 samples, 9 showed C4d-positive immunostaining localized on the endothelia of a few portal veins in the portal tract. The degree of fibrosis was correlated with C4d staining (p = 0.025). The age at Kasai operation correlated with the degree of fibrosis and the C4d positivity. Two needle biopsy samples were positive for C4d. Among 13 samples submitted for VCAM-1 staining, 2 negative samples were C4d negative and all positive C4d samples were VCAM-1 positive with CD45 mononuclear cell infiltration. CONCLUSION: These findings suggest that ongoing cirrhosis could be a result of progressive "vasculopathy" of the portal vein caused by humoral and cell-mediated immune interaction.

New allogeneic hematopoietic stem cell transplantation method: hematopoietic stem cell transplantation plus thymus transplantation for intractable diseases.

Although allogeneic hematopoietic stem cell transplantation (allo-HSCT) has become a valuable strategy for some intractable diseases, a number of problems remain to be resolved. We have developed a new HSCT method, HSCT + thymus transplantation (TT) from the same donor, which induces elevated T cell function with mild graft-versus-host disease (GVHD) in comparison to conventional HSCT alone and HSCT + donor lymphocyte infusion (HSCT + DLI). This new method is effective in the treatment of several intractable diseases and conditions, such as autoimmune diseases in aging, advanced malignant tumors, exposure to supralethal irradiation, multiple organ transplantation from different donors, and type 2 diabetes mellitus, for which conventional methods are ineffective. Our findings suggest that allo-HSCT + TT is preferable to conventional allo-HSCT alone or allo-HSCT + DLI. This method may become a valuable next-generation HSCT technique.

The impact of preoperative muscle strength on postoperative walking ability in patients undergoing total knee arthroplasty.

Although knee extensor muscle strength is strongly associated with postoperative walking ability (PWA) in patients undergoing total knee arthroplasty (TKA), few studies have considered the impact of both knee extensor and flexor muscle strength. This study aimed to determine whether operative side knee flexor and extensor muscle strength before surgery affects the PWA of patients who undergo TKA while accounting for potential covariates. This multicenter retrospective cohort study involved four university hospitals, and patients who underwent unilateral primary TKA were included. The outcome measure was the 5-m maximum walking speed test (MWS), which was completed 12 weeks postoperatively. Muscle strength was measured as the maximum isometric muscle strength required for knee flexor and extensor. Three multiple regression models with a progressively larger number of variables were developed to determine the predictors of 5-m MWS at 12 weeks post-TKA surgery. One hundred thirty-one patients who underwent TKA were enrolled in the study (men, 23.7%; mean age, 73.4 ± 6.9 years). Age, sex, operative side knee flexor muscle strength before surgery, Japanese Orthopaedic Association knee score, and preoperative walking ability were significantly associated with PWA in the final model of the multiple regression analysis ( R2 = 0.35). The current findings suggest that the operative side knee flexor muscle strength before surgery is a robust modifiable predictor of improved PWA. We believe that further validation is needed to determine the causal relationship between preoperative muscle strength and PWA.

Progressive thoracic myelopathy caused by spinal calcium pyrophosphate crystal deposition because of proximal junctional vertebral compression fracture after lumbopelvic fusion.

PURPOSE: We describe cases presenting with progressive thoracic myelopathy after lumbopelvic fusion attributed to proximal junctional vertebral compression fracture (PJF) followed by spinal calcium pyrophosphate dehydrate (CPPD) crystal deposition. METHODS: The study included six patients, ranging from 62 to 75 years. All patients had been treated previously with lumbopelvic fusion. The mean period from the detection of PJF to the onset of myelopathy was 4.8 months. Notably, five patients demonstrated upper-instrumented vertebra (UIV) collapse. RESULTS: After revision surgery involving decompressive laminectomy and extension of the spinal fusion, all patients experienced significant improvement. Photomicrographs of the resected ligamentum flavum showed CPPD crystals and multinucleated giant cells. CONCLUSIONS: The combination of mechanical stress plus PJF and CPPD crystal deposition followed by a foreign body reaction to the deposited crystals caused myelopathy. Patients with radiographic evidence of PJF, especially UIV collapse, after lumbopelvic fusion should be followed carefully for the emergence of myelopathy.

Poorly differentiated squamous cell carcinoma of the nipple: a unique case for marked exophytic growth, but little invasion with neuroendocrine differentiation.

A 73-year-old woman showed marked exophytic growth of a tumor (25 × 23 × 14 mm) of the nipple over a period of 2 months. Histologically, numerous tumor nodules with no apparent keratinization were observed in the exophytic lesion. The tumor cells also showed little invasion to the dermis and no metastasis to the axillary lymph nodes (LN). The tumor cells were immunohistochemically positive for cytokeratins (CKs; AE1/AE3 and 34ßE12), epithelial membrane antigen (EMA), and p53, but negative for Ber-EP4 and human papilloma virus (HPV). The MIB-1 index was 56%. Some tumor cells were also positive for some neuroendocrine markers, and showed some tonofilaments and neurosecretory granules in the cytoplasm under electron microscopy. We made the differential diagnosis of mammary ductal carcinoma, basal cell carcinoma (BCC), Paget's disease, and neuroendocrine carcinoma including Merkel cell carcinoma. The final diagnosis was poorly differentiated squamous cell carcinoma (SCC) showing exophytic growth with neuroendocrine differentiation (ND) in the nipple. To our knowledge, although only five cases of Bowen's disease have been reported in the nipple, such a unique SCC has not been reported previously.

A case of primary retroperitoneal amyloidoma resected laparoscopically.

Amyloidosis is known as a group of diseases that causes various disorders because of deposition of amyloid protein in various organs. Amyloidosis occurring in the retroperitoneum is a rare disease. We report a 75-year-old male patient presented to our hospital because he was identified with a retroperitoneal mass incidentally by CT. Laparoscopic surgery was performed to resect the tumor. In the histopathological specimen, amyloid was found in the fibrous soft tissue by Congo red staining. This is the first report to document a primary solitary amyloidosis of the retroperitoneum without systemic amyloidosis, which was resected using the laparoscopic approach.

Prolonged survival in mice with advanced tumors treated with syngeneic or allogeneic intra-bone marrow-bone marrow transplantation plus fetal thymus transplantation.

Thymic function decreases in line with tumor progression in patients with cancer, resulting in immunodeficiency and a poor prognosis. In the present study, we attempted to restore thymic function by BALB/c (H-2(d)) syngeneic (Syn), or B6 (H-2(b)) allogeneic (Allo) bone marrow transplantation (BMT) using intra-bone marrow-bone marrow transplantation (IBM-BMT) plus Syn-, Allo- or C3H (H-2(k)) 3rd-party fetal thymus transplantation (TT). Although the BALB/c mice with advanced tumors (Meth-A sarcoma; H-2(d), >4 cm(2)) treated with either Syn- or Allo-BMT alone showed a slight improvement in survival compared with non-treated controls, the mice treated with BMT + TT showed a longer survival. The mice treated with Allo-BMT + Allo-TT or 3rd-party TT showed the longest survival. Interestingly, although there was no difference in main tumor size among the BMT groups, lung metastasis was significantly inhibited by Allo-BMT + Allo-TT or 3rd-party TT. Numbers of CD4(+) and CD8(+) T cells, Con A response, and IFN-gamma production increased significantly, whereas number of Gr-1(+)/CD11b(+) myeloid suppressor cells and the percentage of FoxP3(+) cells in CD4(+) T cells significantly decreased in these mice. Furthermore, there was a positive correlation between survival days and the number of T cells or T cell function, while there was a negative correlation between survival days and lung metastasis, the number of Gr-1(+)/CD11b(+) cells, or the percentage of FoxP3(+) cells. These results suggest that BMT + TT, particularly Allo-BMT + Allo-TT or 3rd-party TT, is most effective in prolonging survival as a result of the restoration of T cell function in hosts with advanced tumors.

Successful modulation of type 2 diabetes in db/db mice with intra-bone marrow--bone marrow transplantation plus concurrent thymic transplantation.

There is increasing evidence that both autoimmune and autoinflammatory mechanisms are involved in the development of not only type 1 diabetes mellitus (T1 DM), but also type 2 diabetes mellitus (T2 DM). Our laboratory has focused on this concept, and in earlier efforts replaced the bone marrow cells (BMCs) of leptin receptor-deficient (db/db) mice, an animal model of T2DM, with those of normal C57BL/6 (B6) mice by IBM-BMT. However, the outcome was poor due to incomplete recovery of T cell function. Therefore, we hypothesized that intra-bone marrow-bone marrow transplantation plus thymus transplantation (IBM-BMT + TT) could be used to treat T2 DM by normalizing the T cell imbalance. Hence we addressed this issue by using such dual transplantation and demonstrate herein that seven weeks later, recipient db/db mice manifested improved body weight, reduced levels of blood glucose, and a reduction of plasma IL-6 and IL-1ß. More importantly, this treatment regimen showed normal CD4/CD8 ratios, and increased plasma adiponectin levels, insulin sensitivity, and the number of insulin-producing cells. Furthermore, the expression of pancreatic pAKT, pLKB1, pAMPK and HO-1 was increased in the mice treated with IBM-BMT + TT. Our data show that IBM-BMT + TT treatment normalizes T cell subsets, cytokine imbalance and insulin sensitivity in the db/db mouse, suggesting that IBM-BMT + TT is a viable therapeutic option in the treatment of T2 DM.

Adult thymus transplantation with allogeneic intra-bone marrow-bone marrow transplantation from same donor induces high thymopoiesis, mild graft-versus-host reaction and strong graft-versus-tumour effects.

Although allogeneic bone marrow transplantation (BMT) plus donor lymphocyte infusion (DLI) is performed for solid tumours to enhance graft-versus-tumour (GVT) effects, a graft-versus-host reaction (GVHR) is also elicited. We carried out intra-bone marrow-bone marrow transplantation (IBM-BMT) plus adult thymus transplantation (ATT) from the same donor to supply alloreactive T cells continually. Normal mice treated with IBM-BMT + ATT survived for a long time with high donor-derived thymopoiesis and mild GVHR. The percentage of CD4(+) FoxP3(+) regulatory T cells in the spleen of the mice treated with IBM-BMT + ATT was lower than in normal B6 mice or mice treated with IBM-BMT alone, but higher than in mice treated with IBM-BMT + DLI; the mice treated with IBM-BMT + DLI showed severe GVHR. In tumour-bearing mice, tumour growth was more strongly inhibited by IBM-BMT + ATT than by IBM-BMT alone. Mice treated with IBM-BMT + a high dose of DLI also showed tumour regression comparable to that of mice treated with IBM-BMT + ATT but died early of GVHD. By contrast, mice treated with IBM-BMT + a low dose of DLI showed longer survival but less tumour regression than the mice treated with IBM-BMT + ATT. Histologically, significant numbers of CD8(+) T cells were found to have infiltrated the tumour in the mice treated with IBM-BMT + ATT. The number of terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labelling (TUNEL)-positive apoptotic tumour cells also significantly increased in the mice treated with IBM-BMT + ATT. Allogeneic IBM-BMT + ATT thus can induce high thymopoiesis, preserving strong GVT effects without severe GVHR.

Preferential expansion of human umbilical cord blood-derived CD34-positive cells on major histocompatibility complex-matched amnion-derived mesenchymal stem cells.

BACKGROUND: We previously found in a murine hematopoietic system that hematopoietic stem cells show high differentiation and proliferation capacity on bone marrow-derived mesenchymal stem cells/stromal cells (microenvironment) with "self" major histocompatibility complex (MHC). DESIGN AND METHODS: We examined whether amnion-derived adherent cells have the characteristics of mesenchymal stem cells, and whether these adherent cells can support the proliferation of umbilical cord blood-derived lineage-negative and CD34-positive cells (Lin(-)CD34(+) cells) obtained from the same fetus to a greater extent than those derived from other fetuses. RESULTS: Culture-expanded amnion-derived adherent cells expressed mesenchymal stem cell markers and HLA-ABC molecules and could differentiate into osteoblasts, adipocytes and chondrocyte-like cells, indicating that the cells have the characteristics of mesenchymal stem cells. The Lin(-)CD34(+) cells purified from the frozen umbilical cord blood were strongly positive for HLA-ABC, and contained a large number of hematopoietic stem cells. When the Lin(-)CD34(+) cells were cultured on the autologous (MHC-matched) or MHC-mismatched amnion-derived adherent cells in short-term assays (hematopoietic stem cell-proliferation) and long-term culture-initiating cell assays, greater expansion of the Lin(-)CD34(+) cells was observed in the MHC-matched combination than in MHC-mismatched combinations. The concentration of granulocyte-macrophage colony-stimulating factor in the culture supernatants of the long-term culture-initiating cell assays was significantly higher in the MHC-matched combination than in MHC-mismatched combinations. CONCLUSIONS: IT is likely that a MHC restriction exists between hematopoietic stem cells and mesenchymal stem cells/stromal cells in the human hematopoietic system and that granulocute-macropage colony-stimulating factor contributes to some extent to the preferential hematopoiesis-supporting ability of the MHC-matched amnion-derived adherent cells.

Maternal HLA class I compatibility in patients with biliary atresia.

Biliary atresia (BA) is an inflammatory cholangiopathy of unknown etiology. Maternal microchimerism has been identified in the livers of patients with BA. We analyzed the human leukocyte antigen (HLA) compatibility between 57 BA patient-mother pairs and 50 control-mother pairs. The HLA class I matching was significantly more frequent in BA pairs (odds ratio [OR]=2.46) than controls. Similar results were also found in child-to-mother HLA compatibility (OR=2.16). Our results indicate that patients with BA have an immunogenetic histocompatible relationship with their mothers, which may result in an increase in maternal microchimerism found in BA.