Intercellular cross-talk through lineage-specific gap junction of cancer-associated fibroblasts related to stromal fibrosis and prognosis.

Stromal fibrosis in cancer is usually associated with poor prognosis and chemotherapy resistance. It is thought to be caused by fibroblasts; however, the exact mechanism is not yet well understood. The study aimed to identify lineage-specific cancer-associated fibroblast (CAF) subgroup and their associations with extracellular matrix remodeling and clinical significances in various tumor types using single-cell and bulk RNA sequencing data. Through unsupervised clustering, six subclusters of CAFs were identified, including a cluster with exclusively high gap junction protein beta-2 (GJB2) expression. This cluster was named GJB2-positive CAF. It was found to be a unique subgroup of terminally differentiated CAFs associated with collagen gene expression and extracellular matrix remodeling. GJB2-positive CAFs showed higher communication frequency with vascular endothelial cells and cancer cells than GJB2-negative CAFs. Moreover, GJB2 was poorly expressed in normal tissues, indicating that its expression is dependent on interaction with other cells, including vascular endothelial cells and cancer cells. Finally, the study investigated the clinical significance of GJB2 signature score for GJB2-positive CAFs in cancer and found a correlation with poor prognosis. These results suggest that GJB2-positive CAF is a unique fibroblast subtype involved in extracellular matrix remodeling, with significant clinical implications in cancer.

Beneficial effects of pretransplantation microchimerism on rejection-free survival in HLA-haploidentical family donor renal transplantation.

BACKGROUND: Fetal-maternal microchimerism (MC) can develop during pregnancy and may persist for decades. Pretransplantation fetal-maternal MC may be present between mother and child and between siblings; however, its effect on renal transplantation is not known. We investigated the effects of pretransplantation MC on allograft outcomes in human leukocyte antigen (HLA)-haploidentical family donor transplantation. METHODS: A total of 106 cases transplanted from 1996 to 2004 were retrospectively studied, with median follow-up of 96 months. The study and control groups included 63 and 43 cases of HLA-haploidentical and HLA-identical donor transplantations, respectively. MC against mismatched donor HLA-DRB1 allele was detected in the recipient's peripheral blood using nested polymerase chain reaction-single-strand conformation polymorphism method. The allograft outcomes of HLA-haploidentical MC (+) and (-) subgroups were compared with those of HLA-identical group. RESULTS: Pretransplantation MC in the HLA-haploidentical recipients was detected in 22.2% (14 of 63). Compared with HLA-identical group, MC (-) subgroup showed significantly inferior allograft outcomes: higher acute rejection rate (11.6% vs. 42.9%; P=0.001), higher 5-year serum creatinine level (1.1 vs. 1.4 mg/dL; P=0.009), and lower 10-year rejection-free survival rate (83.7% vs. 54.5%; log-rank P=0.001). In contrast, MC (+) subgroup showed no significant differences from HLA-identical group in acute rejection rate (14.3%), 5-year serum creatinine level (1.1 mg/dL), and 10-year rejection-free survival rate (85.7%). Multivariate analysis revealed that pretransplantation MC is associated with a significantly lower risk of acute rejection (odds ratio=0.10; P=0.021). CONCLUSION: Pretransplantation MC present in the recipient may have beneficial effects on rejection-free allograft survival in renal transplantation.

Detection of HLA-DRB1 microchimerism using nested polymerase chain reaction and single-strand conformation polymorphism analysis.

For the detection of microchimerism, molecular methods detecting donor-specific HLA-DRB1 alleles in the recipient are most commonly used. Nested polymerase chain reaction sequence specific primer (nested PCR-SSP) methods widely used to increase the sensitivity of detection have been reported to give frequent false-positive reactions. We have developed a new method combining nested PCR with single-strand conformation polymorphism analysis (nested PCR-SSCP) and tested the 1 to 0.00001% level of microchimerism for 27 different HLA-DRB1 alleles. For most (26/27) of the HLA-DRB1 alleles tested, this method could detect 0.01 to 0.001% of microchimerism and its sensitivity was equal to or better than that of nested PCR-SSP tested in parallel. Its specificity was verified by visualizing particular DRB1-specific SSCP bands under test. Nested PCR-SSP indicated frequent false-positive reactions, mainly caused by nonspecific amplification of DRB3/B4/B5 alleles present in the major (recipient) DNAs. We have compared a real-time quantitative PCR for non-human leukocyte antigen (HLA) target (insertion/deletion marker) using a commercial kit (AlleleSEQR Chimerism assay), and its microchimerism detection sensitivity (around 0.1%) was 1 step (10 times) lower than that of nested PCR-SSP or -SSCP methods for HLA-DRB1 alleles. We validated that the newly designed nested PCR-SSCP affords good sensitivity and specificity and may be useful for studying microchimerism in clinical settings.

Serum HBsAg levels during peginterferon α-2a treatment with or without thymosin α-1 in HBeAg-positive chronic hepatitis B patients.

The importance of serum hepatitis B surface antigen (HBsAg) level as a surrogate marker for viral load and a predictor of treatment response remains unclear. The aim of this study was to investigate whether serum HBsAg correlates with serum hepatitis B virus (HBV) DNA during peginterferon (PEG-IFN) α-2a treatment (with or without thymosin α-1) in hepatitis B e antigen (HBeAg)-positive chronic hepatitis B patients and whether it can predict treatment response. Sera from 37 HBeAg-positive chronic hepatitis B patients receiving 48-weeks PEG-IFN α-2a with (n = 20) or without (n = 17) an initial 12-weeks thymosin α-1 were obtained at baseline and at weeks 12, 24, 36, 48 (end of treatment), 56, 72, 84, and 96 (end of follow-up). Taqman HBV DNA tests (Roche) and Architect HBsAg QT (Abbott) were performed. There was a moderate correlation between the HBsAg and HBV DNA levels (r = 0.452, P < 0.001). Median HBsAg levels at baseline and at week 96 were 6,218 IU/ml and 4,038 IU/ml, respectively. The mean HBV DNA and alanine aminotransferase (ALT) levels were 7.48 log(10) IU/ml and 173 IU/L at baseline and 5.37 log(10) IU/ml and 102 IU/L at week 96, respectively. A decrease to <60% of baseline levels of HBsAg at week 12 was identified as an independent predictive factor for HBeAg seroconversion (OR = 45.7, P < 0.05) at week 96. Serum HBsAg levels may be helpful for predicting the response to PEG-IFN therapy in HBeAg-positive chronic hepatitis B patients.