RNASEH1-AS1 induced by H3K27ac stabilizes ANXA2 mRNA to promote the progression of colorectal cancer through recruiting BUD13.

Colorectal cancer (CRC) is a malignant tumor with high morbidity and mortality. It is well-accepted that dysregulated lncRNAs are closely related to the development of CRC. In this study, the function and mechanism of RNASEH1-AS1 in CRC were investigated. RT-qPCR and western blot detected the expression of targeted genes in tissues and cells. CCK-8, clone formation, wound healing assay, and Transwell were applied to evaluate CRC cell malignant behaviors. ChIP, RIP, and RNA pull-down validated interactions among RNASEH1-AS1, H3K27ac, CBP, BUD13, and ANXA2. Nucleoplasmic separation and FISH assay determined the location of RNASEH1-AS1 in CRC cells. IHC assay was used to detect Ki-67 expression in tumor tissues from mice. RNASEH1-AS1 was highly expressed in CRC tumor tissues and cells. RNASEH1-AS1 silencing effectively suppressed the viability, proliferation, migration, and invasion of CRC cells. In addition, CBP-mediated H3K27ac increased RNASEH1-AS1 expression in CRC cells and RNASEH1-AS1 could elevate ANXA2 expression through recruiting BUD13. Furthermore, RNASEH1-AS1 silencing inhibited malignant phenotypes of CRC cells and tumor growth in mice through decreasing ANXA2 expression and inactivating the Wnt/ß-catenin pathway. Our results revealed that RNASEH1-AS1 induced by CBP-mediated H3K27ac activated Wnt/ß-catenin pathway to promote CRC progression through recruiting BUD13 to stabilize ANXA2 mRNA, which provides substantial evidence of RNASEH1-AS1 in CRC. Targeting RNASEH1-AS1 might alleviate CRC progression.

[Functions of inflammatory factor in non-tumor deep venous thrombosis of lower extremity].

OBJECTIVE: To explore the functions of inflammatory cytokine, tissue factor (TF) and cancer procoagulant (CP) in non-tumor deep venous thrombosis (NT-DVT). METHODS: A total of 17 NT-DVT patients (5 males and 12 females) were selected for NT-DVT group while 20 voluntary (10 males and 10 females) blood donors for control group from May 2012 to March 2013. The levels of inflammatory cytokines interleukin 1ß (IL-1 ß), IL-18, tumor necrosis factor alpha (TNF-α), TF and CP were tested by enzyme-linked immunosorbent assay (ELISA) before and after treatment. Also the correlations of inflammatory cytokines and TF were determined. RESULTS: The levels of inflammatory cytokines and TF were higher in NT-DVT than those in control group pre-treatment ((153.13 ± 2.30) vs (59.26 ± 1.57) ng/L, (364.27 ± 1.46) vs (67.46 ± 1.48) ng/L, (363.51 ± 1.85) vs (216.42 ± 1.55) µg/L, (66.90 ± 1.44) vs (14.55 ± 1.52) ng/L, all P < 0.05). And after anticoagulant therapy, the levels decreased (all P < 0.05). Also the levels of IL-1ß,IL-18 and TNF-α were positively correlated with TF pre-treatment. And the correlation coefficients were 0.492 (P = 0.045), 0.652 (P = 0.005) and 0.511(P = 0.036) respectively. Compared with control group, the plasma level of CP had no obvious change before and after treatment (both P > 0.05). CONCLUSION: A high level of inflammatory cytokines is an important risk factor for NT-DVT.

Donor-derived Anti-CD19 CAR T cells GC007g for relapsed or refractory B-cell acute lymphoblastic leukemia after allogeneic HSCT: a phase 1 trial.

Background: Although chimeric antigen receptor-modified T cells (CAR T) cell therapy has been widely reported in improving the outcomes of B-cell acute lymphoblastic leukemia (B-ALL), less research about the feasibility and safety of donor-derived CAR T after allogeneic hematopoietic stem cell transplantation (allo-HSCT) was reported. Methods: This phase 1 clinical trial aims to evaluate safety and efficacy of donor-derived anti-CD19 CAR T cells (GC007g) in B-ALL patients who relapsed after allo-HSCT. This trial is registered with ClinicalTrials.gov, NCT04516551. Findings: Between 15 March 2021 and 19 May 2022, fifteen patients were screened, three patients were excluded due to withdraw of consent, donor's reason, and death, respectively. Patients received donor-derived CAR T cells infusions at 6 × 105/kg (n = 3) or 2 × 106/kg (n = 6) dose level. The median time from HSCT to relapse was 185 days (range, 81-2063). The median age of patients was 31 years (range 21-48). Seven patients (77.8%) had BCR-ABL fusion gene. CAR T cells expanded in vivo and the median time to reach Cmax was 9 days (range, 7-11). One patient had hyperbilirubinemia after GC007g infusion which was defined as a dose-limiting toxicity. All patients experienced CRS and hematological adverse events. Three patients had acute graft-versus-host-disease (grade I, n = 1; grade II, n = 1; grade IV, n = 1) and all resolved after treatment. They received CAR T cells from matched sister, haploidentical matched father and sisiter, respectively. At 28 days after infusion, all patients achieved complete remission with/without incomplete hematologic recovery (CRi/CR) with undetectable MRD. At a median follow-up of 475 days (range 322-732), seven patients remained in CR/CRi while two had CD19-negative relapse. The overall response rates (ORR) were 100% (9/9), 88.9% (8/9), and 75% (6/8) at 3 month, 6 month, and 12 month, respectively. The 1-year progression-free and overall survival were 77.8% and 85.7%, respectively. Interpretation: GC007g expanded and induced durable remission in patients with B-ALL relapsed after allo-HSCT, with manageable safety profiles. Funding: Gracell Biotechnologies Inc.

[The In Vivo Intervention and Relative Mechanism of Genistein on the Inflammation and Thrombophilia in Lymphoma-Bearing Mice].

OBJECTIVE: To investigate the in vivo intervention and relative mechanism of Genistein (GEN) on tumor-associated inflammatory and tumor thrombophilia in lymphoma-bearing mice. METHODS: Forty female Balb/c mice aged 5-6 weeks were injected with murine-derived Pro B-cell lymphoma cell line 38B9 to establish a lymphoma mouse model, which was randomly divided into control group, tumor-bearing group, GEN drug intervention group and cyclophosphamide (CTX）drug intervention group. Histopathologic was used to evaluate the tumorigenesis. Tumor formation was observed, and tumor tissues were collected of HE and immunohistochemical staining. ELISA and flow cytometry were used to detect the expression of inflammatory factors and the changes of thrombus indices in plasma after intervention of GEN and Cyclophosphamide (CTX) respectively. Immunohistochemistry method was used to detect the expression of CD19 in tomor tissues of tummor bearing mice. RESULTS: After 14 days of tumor bearing, the mice were tumorigenic. The lymphoma cells were diffusely distributed in the tumor tissue and the expression of CD19 in the tumor tissue was positive. The inflammatory factors such as IL-6, NETs and CLEC-2, and thrombotic indices such as TF, FIB and D-D in lymphoma-bearing mice were significantly higher than those before tumor-injection and lower than those after drug-intervention (all P<0.05). The levels of CLEC-2 and D-D in GEN group were significantly lower than those in CTX group (P<0.05). CONCLUSION: Tumor-associated inflammation and thrombophilia exist in lymphoma-bearing mice. GEN shows better anti-inflammatory and anti-thrombotic effects compared with CTX by interfering with tumor inflammatory factors.

CD7 targeted "off-the-shelf" CAR-T demonstrates robust in vivo expansion and high efficacy in the treatment of patients with relapsed and refractory T cell malignancies.

T-cell acute lymphoblastic leukemia (T-ALL) represents an area of highly unmet medical needs. Once relapsed, patients have limited treatment options and poor prognosis. T-ALL antigens such as CD7 is extensively expressed in normal T cells and natural killer (NK) cells, and extending the success of CAR-T therapy to T cell malignancies was challenged by CAR-T cell fratricide, high production cost, and potential product contaminations. GC027 is an "off-the-shelf" allogeneic CD7 targeted CAR-T therapeutic product for T cell malignancies. It demonstrated superior cell expansion and antileukemia efficacy in mouse xenograft model. In our previous study, we observed promising efficacy results in the first two relapsed and refractory(R/R) T-ALL patients treated with GC027. In the expanded study, 11 out of 12 patients had rapid eradication of T-lymphoblasts and reached complete response within 1-month after GC027 infusion. GC027 cells expanded quickly beginning at infusion and reached to peak around 5-10 days after infusion. For most patients with a response(9/11), GC027 could not be detected via flow cytometry or qPCR 4 weeks after infusion. One patient had progression free survival of >3 years. With manageable toxicity profile, GC027 demonstrated superior clinical efficacy to standard chemotherapy regimens in (R/R) T cell malignancies.

Proteases in MHC class I presentation and cross-presentation.

Cells that have mutated their genes or are virally infected are a potential threat to a host. Consequently, the immune system has evolved mechanisms for CD8 T lymphocytes to identify such cells and eliminate them. The generation of CD8 T cell responses occurs in two phases, both of which critically involve the process of Ag presentation. In the first phase, sentinel cells gather Ags present in tissues and then present them to naive CD8 T cells in ways that stimulate their maturation into effectors. In the second phase, these effector cells seek out and eliminate the pathological cells. The abnormal cells are identified through their presentation of immunogenic Ags that they are producing. The Ag presentation mechanisms used by the sentinel cells can be different from those in other cells. This article will review these mechanisms with a focus in each case on how antigenic peptides are generated for presentation.

TLR4 is a negative regulator in noninfectious lung inflammation.

Low m.w. hyaluronan (LMW HA) has been shown to elicit the expression of proinflammatory cytokines and chemokines in various cells in vitro. However, the effects of this molecule in vivo are unknown. In this study, we report that intratracheal administration of LMW HA (200 kDa) causes inflammation in mouse lung. A lack of TLR4 is associated with even stronger inflammatory response in the lung as shown by increased neutrophil counts and elevated cytokine and chemokine concentrations. We also demonstrate that TLR4 anti-inflammatory signaling is dependent upon a MyD88-independent pathway. TLR4-mediated IL-1R antagonist production plays a negative regulatory role in LMW HA (200 kDa) induced lung inflammation. These data provide a molecular level explanation for the function of TLR4 in LMW HA (200 kDa)-induced lung inflammation, as inhibition of the beta form of pro-IL-1 promotes an anti-inflammatory response.

Exploiting T cell signaling to optimize engineered T cell therapies.

Engineered T cell therapies, mainly chimeric antigen receptor (CAR)-T and T cell receptor (TCR)-T, have become the new frontier of cancer treatment. CAR-T and TCR-T therapies differ in many aspects, including cell persistence and toxicity, leading to different therapeutic outcomes. Both TCR and CAR recognize antigens and trigger T cell mediated antitumor response, but they have distinct molecular structures and signaling properties. TCR represents one of the most complex receptors, while CAR is a single-chain chimera integrating modules from multiple immune receptors. Understanding the mechanisms underlying the strengths and limitations of both systems can pave the way for the development of next-generation T cell therapy. This review synthesizes recent findings on TCR and CAR signaling and highlights the potential strategies of T cell engineering by signaling refinement.

Protein S gene mutation c.946C > T (p.R316C) contributed to ischemic stroke in a man with von Willebrand disease type 3 caused by two novel VWF gene mutations, c.2328delT (p.A778Lfs* 23) and c.6521G > T (p.C2174F).

The risk factors for a family with VWD presenting with an ischemic stroke (IS) were explored. FVIII activity (FVIII:C), VWF antigen (VWF:Ag), and protein S activity were measured. Next generation sequencing (NGS) was performed targeting F8, F9, VWF, PROC, and PROS1. Sanger sequencing validation was performed on family members. The proband and his sister both had low FVIII:C (1 IU/dL) and VWF:Ag (3 IU/dL) levels, confirming the diagnosis of type 3 VWD. His father had nearly normal levels of FVIII:C (58 IU/dL) and VWF:Ag (57 IU/dL). His daughter had type 1 VWD with decreased FVIII:C (46 IU/dL) and VWF:Ag (19 IU/dL). NGS identified a heterozygous VWF c.2328delT (p.A778Lfs*23) frame shift mutation only in the proband and his sister. Another VWF missense mutation, c.6521G > T (p.C2174F), was found heterozygous in all members studied. A PROS1 mutation, c.946C > T (p.R316C), previously reported to relate to ischemic stroke, was found heterozygous in the patient, his father, and his daughter. Only the proband and daughter have a slightly decreased plasma protein S level. This may be the first case with type 3 VWD with severe VWF/FVIII deficiency presented with ischemic stroke contributed to by a protein S defect.

Next-day manufacture of a novel anti-CD19 CAR-T therapy for B-cell acute lymphoblastic leukemia: first-in-human clinical study.

To improve clinical outcomes and shorten the vein-to-vein time of chimeric antigen receptor T (CAR-T) cells, we developed the FasT CAR-T (F-CAR-T) next-day manufacturing platform. We report the preclinical and first-in-human clinical studies evaluating the safety, feasibility, and preliminary efficacy of CD19 F-CAR-T in B-cell acute lymphoblastic leukemia (B-ALL). CD19 F-CAR-T cells demonstrated excellent proliferation with a younger cellular phenotype, less exhaustion, and more effective tumor elimination compared to conventional CAR-T cells in the preclinical study. In our phase I study (NCT03825718), F-CAR-T cells were successfully manufactured and infused in all of the 25 enrolled pediatric and adult patients with B-ALL. CD19 F-CAR-T safety profile was manageable with 24% grade 3 cytokine release syndrome (CRS) and 28% grade 3/4 neurotoxicity occurring predominantly in pediatric patients. On day 14, 23/25 patients achieved minimal residual disease (MRD)-negative complete remission (CR), and 20 subsequently underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT) within 3 months post F-CAR-T therapy. Fifteen of 20 patients were disease-free with a median remission duration of 734 days. One patient relapsed and 4/20 died from transplant-related mortality. Of the three patients who did not undergo allo-HSCT, two remained in CR until 10 months post-F-CAR-T. Our data indicate that anti-CD19 FasT CAR-T shows promising early efficacy for B-ALL. Further evaluations in larger clinical studies are needed.

Novel CD19 chimeric antigen receptor T cells manufactured next-day for acute lymphoblastic leukemia.

Chimeric antigen receptor-engineered T (CAR-T) cells have shown promising efficacy in patients with relapsed/refractory B cell acute lymphoblastic leukemia (R/R B-ALL). However, challenges remain including long manufacturing processes that need to be overcome. We presented the CD19-targeting CAR-T cell product GC007F manufactured next-day (FasTCAR-T cells) and administered to patients with R/R B-ALL. A total of 21 patients over 14 years of age with CD19+ R/R B-ALL were screened, enrolled and infused with a single infusion of GC007F CAR-T at three different dose levels. The primary objective of the study was to assess safety, secondary objectives included pharmacokinetics of GC007F cells in patients with R/R B-ALL and preliminary efficacy. We were able to demonstrate in preclinical studies that GC007F cells exhibited better proliferation and tumor killing than conventional CAR-T (C-CAR-T) cells. In this investigator-initiated study all 18 efficacy-evaluable patients achieved a complete remission (CR) (18/18, 100.00%) by day 28, with 17 of the patients (94.4%) achieving CR with minimal residual disease (MRD) negative. Fifteen (83.3%) remained disease free at the 3-month assessment, 14 patients (77.8%) maintaining MRD negative at month 3. Among all 21 enrolled patients, the median peak of CAR-T cell was on day 10, with a median peak copy number of 104899.5/µg DNA and a median persistence period of 56 days (range: 7-327 days). The incidence of cytokine release syndrome (CRS) was 95.2% (n = 20), with severe CRS occurring in 52.4% (n = 11) of the patients. Six patients (28.6%) developed neurotoxicity of any grade. GC007F demonstrated superior expansion capacity and a less exhausted phenotype as compared to (C-CAR-T) cells. Moreover, this first-in-human clinical study showed that the novel, next-day manufacturing FasTCAR-T cells was feasible with a manageable toxicity profile in patients with R/R B-ALL.

Prevalence and genotype distribution of high-risk human papillomavirus infection among women with cervical cytological abnormalities in Chongqing, China, 2014-2020.

BACKGROUND: Persistent infection with high-risk human papillomavirus (HR-HPV) is the main leading cause of cervical precancerous lesions and cervical cancer. This study aims to explore the epidemiological characteristics of HR-HPV genotypes and their correlation with the ThinPrep cytological test (TCT) results among women in Chongqing, in China. METHODS: In this retrospective study, cervical exfoliations of 14,548 women who visited Chongqing university cancer hospital were collected for detecting HR-HPV genotypes and TCT. RESULTS: Overall, the rate of HR-HPV infection was 14.26%. The three most common HR-HPV genotypes are HPV52 (4.39%), HPV58 (2.21%), and HPV16 (1.94%). In this study, the positive rate of cervical TCT was 4.54%. Atypical squamous cells of undetermined significance (ASC-US), atypical squamous cells that could not exclude high-grade squamous intraepithelial lesion (ASU-H), low-grade squamous intraepithelial lesions (LSIL), high-grade squamous intraepithelial lesions (HSIL), and atypical glandular cells of undetermined significance (AGC) were 2.99%, 0.20%, 0.92%, 0.29%, and 0.14%, respectively. Among the several types of cytological lesions, the HR-HPV infection rates of ASC-US, ASC-H, LSIL, HSIL, and (AGC) were 24.82%, 41.38%, 64.18%, 95.24%, and 23.81%, respectively. CONCLUSIONS: HPV52, HPV 58, and HPV16 are the most common infection subtypes in Chongqing. When implementing HPV vaccine programs in Chongqing, HPV58 and HPV52 should be attached importance as HPV16 and HPV18.

Phase I study of CAR-T cells with PD-1 and TCR disruption in mesothelin-positive solid tumors.

Programmed cell death protein-1 (PD-1)-mediated immunosuppression has been proposed to contribute to the limited clinical efficacy of chimeric antigen receptor T (CAR-T) cells in solid tumors. We generated PD-1 and T cell receptor (TCR) deficient mesothelin-specific CAR-T (MPTK-CAR-T) cells using CRISPR-Cas9 technology and evaluated them in a dose-escalation study. A total of 15 patients received one or more infusions of MPTK-CAR-T cells without prior lymphodepletion. No dose-limiting toxicity or unexpected adverse events were observed in any of the 15 patients. The best overall response was stable disease (2/15 patients). Circulating MPTK-CAR-T cells peaked at days 7-14 and became undetectable beyond 1 month. TCR-positive CAR-T cells rather than TCR-negative CAR-T cells were predominantly detected in effusion or peripheral blood from three patients after infusion. We further confirmed the reduced persistence of TCR-deficient CAR-T cells in animal models. Our results establish the preliminary feasibility and safety of CRISPR-engineered CAR-T cells with PD-1 disruption and suggest that the natural TCR plays an important role in the persistence of CAR-T cells when treating solid tumors.

Eradication of T-ALL Cells by CD7-targeted Universal CAR-T Cells and Initial Test of Ruxolitinib-based CRS Management.

PURPOSE: Although chimeric antigen receptor T-cell (CAR-T) therapy development for B-cell malignancies has made significant progress in the last decade, broadening the success to treating T-cell acute lymphoblastic leukemia (T-ALL) has been limited. We conducted two clinical trials to verify the safety and efficacy of GC027, an "off-the-shelf" allogeneic CAR-T product targeting T-cell antigen, CD7. Here, we report 2 patients as case reports with relapsed/refractory T-ALL who were treated with GC027. PATIENTS AND METHODS: Both the trials reported here were open-label and single-arm. A single infusion of GC027 was given to each patient after preconditioning therapy. RESULT: Robust expansion of CAR-T cells along with rapid eradication of CD7+ T lymphoblasts were observed in the peripheral blood, bone marrow, and cerebrospinal fluid. Both patients achieved complete remission with no detectable minimal residual disease. At data cutoff, 30 September 2020, 1 of the 2 patients remains in ongoing remission for over 1 year after CAR T-cell infusion. Grade 3 cytokine release syndrome (CRS) occurred in both patients and was managed by a novel approach with a ruxolitinib-based CRS management. Ruxolitinib showed promising activity in a preclinical study conducted at our center. No graft-versus-host disease was observed. CONCLUSIONS: The two case reports demonstrate that a standalone therapy with this novel CD7-targeted "off-the-shelf" allogeneic CAR-T therapy may provide deep and durable responses in select patients with relapsed/refractory T-ALL. GC027 might have a potential to be a promising new approach for treating refractory/relapsed T-ALL. Further studies are warranted.

Granzyme A from cytotoxic lymphocytes cleaves GSDMB to trigger pyroptosis in target cells.

Cytotoxic lymphocyte-mediated immunity relies on granzymes. Granzymes are thought to kill target cells by inducing apoptosis, although the underlying mechanisms are not fully understood. Here, we report that natural killer cells and cytotoxic T lymphocytes kill gasdermin B (GSDMB)-positive cells through pyroptosis, a form of proinflammatory cell death executed by the gasdermin family of pore-forming proteins. Killing results from the cleavage of GSDMB by lymphocyte-derived granzyme A (GZMA), which unleashes its pore-forming activity. Interferon-γ (IFN-γ) up-regulates GSDMB expression and promotes pyroptosis. GSDMB is highly expressed in certain tissues, particularly digestive tract epithelia, including derived tumors. Introducing GZMA-cleavable GSDMB into mouse cancer cells promotes tumor clearance in mice. This study establishes gasdermin-mediated pyroptosis as a cytotoxic lymphocyte-killing mechanism, which may enhance antitumor immunity.

Priming of T cells by exogenous antigen cross-presented on MHC class I molecules.

Cross-presentation is the process whereby bone-marrow-derived antigen-presenting cells acquire, process and present exogenous antigen as peptides bound to MHC class I molecules to CD8(+) T cells. Professional antigen-presenting cells acquire cell-associated antigen predominantly in the form of protein, then process and present antigenic peptides on their surface MHC class I molecules via several mechanisms and efficiently cross-prime naïve CD8(+) T cells in vivo. This pathway is of considerable interest because it has an important role in the immune surveillance of tissues for pathogens and cancers.

[Effect of Coagulation and Platelet Activation on Tumor-Associated Hypercoagulable State in Lymphoma-Bearing Mice].

OBJECTIVE: To investigate the coagulation abnormality and tumor-associated hypercoagulable state in lymphoma-bearing mice by measuring the changes in coagulation indices (D-D, vWF, TF) and platelet activation indices (P-selectin, GPIIbIIIa). METHODS: The mouse model with lymphoma was established by the subcutaneous injection of 38B9 lymphoma cells into BALB/c mice, and the tumor formation was evaluated by using MRI and B ultrasonography. The D-D, vWF and TP levels of blood samples from inner canthal vein of tumor-bearing mice on 1 d, 14 d and 21 d were detected by using ELISA, the platelet activation indices (P-selectin, GPIIbIIIa) were detected by using flow cytometry. RESULTS: The lymphoma-bearing mouse model was successfully established. The levels of D-D, vWF and TF as well as platelet activation indices P-selectin and GPIIbIIIa in the peripheraI blood were significantly higher than those of control group (P<0.05). CONCLUSION: Lymphoma-bearing mice showed abnormalities of coagulation and platelet activation, which relates with the tumor hypercoagulable state in lymphoma-bearing mice.

[Regulation of UC-MSC on Immune Inflammatory Thrombophilia in MRL/lpr Mice].

OBJECTIVE: To study the immune repair effect of umbilical cord mesenchymal stem cells (UC-MSC) on inflammatory disorders and thrombophilia state of MRL/lpr mice by detecting the expression change of peripheral blood CD4(+) CD25(+) T cells and the levels of plasma inflammatory cytokines TNF-α, IL-6 and thrombosis indicators TF, FIB. METHODS: Twenty five MRL/lpr mice were divided into control (C) group, UC-MSC one time treatment (UT1) group and UC-MSC three time treatments (UT3) group. UC-MSC cell suspension was injecled via tail vein and these mice were feeded in SPF environment. The blood samples were taken from the mice every 2 weeks after 16(th) week. FCM was used to detect the expression of CD4(+) CD25(+) T cells in peripheral blood, ELISA assay was used to detect the levels of inflammatory cytokines TNF-α, IL-6 and thrombosis indicators TF, FIB. RESULTS: The expression of peripheral blood CD4(+) CD25(+) T cells in treatment groups increased during 16(th) to 18(th) week, dropped and tended to be stable since 20(th) week, and lower than those in control group. The levels of plasma TNF-α and IL-6 in treatment group decreased since 16(th) week and significantly lower than those in control group (P < 0.05). The levels of plasma TF and FIB in treatment group decreased since 16(th) week. The level of plasma TF in treatment group was significantly lower than those in control group (P < 0.05) since 18(th) week. CONCLUSION: UC-MSC can repair the immune inflammatory microenvironment disorders of MRL/lpr mice through its immunomodulatory effect. UC-MSC contribute to repair of immune inflammatory thrombophilia of MRL/lpr mice.

[Immunomodulatory effect of UC-MSC on function of immunocytes of rats with collagen type II induced arthritis].

This study was purposed to observe the influence of umbilical cord mesenchymal stem cells (UC-MSC) on the peripheral blood CD4(+)CD25(+)regulatory T cells (Treg), Th17 cells and neutrophils in rats with collagen type II-induced arthritis(CIA), and to explore the regulating effect of UC-MSC transplantation on immunocyte subgroup. The rats wee divided into 3 groups: CIA group (model group), UC-MSC treated group and blank control group. The CIA rats were injected with UC-MSC via tail vein. The percentage of CD4(+)CD25(+) cells in peripheral blood and the expression of NCD11b on neutrophil surface in CIA rates was detected by flow cytometry (FCM), and the serum interleukin-17 (IL-17) was observed by enzyme-linked immunosorbent assay (ELISA). The results showed that the mean fluorescence intensity(MFI) of NCD11b and the level of IL-17 in the model group were significantly higher than those in the blank control group, and the ratio of CD4(+)CD25(+) cells were significantly lower (P < 0.05). The MIF of NCD11b and the level of IL-17 in the UC-MSC treated group were significantly lower than that in the model group (P < 0.05), while the proportion of CD4(+)CD25(+) Treg increased (P < 0.05). Since the fifth week, the above indicators in the UC-MSC group have almostly approached the control group. It is concluded that the UC-MSC can increase peripheral blood Treg proportion in CIA rat, inhibit the secretion of Th17 and the activity of neutrophils, reduce the immune inflammation reaction, decrease the release of proinflammatory factor, and induce immune reconstruction.

Assessment of roles for calreticulin in the cross-presentation of soluble and bead-associated antigens.

Antigen cross-presentation involves the uptake and processing of exogenously derived antigens and their assembly with major histocompatibility complex (MHC) class I molecules. Antigen presenting cells (APC) load peptides derived from the exogenous antigens onto MHC class I molecules for presentation to CD8 T cells. Calreticulin has been suggested to mediate and enhance antigen cross-presentation of soluble and cell-derived antigens. In this study, we examined roles for calreticulin in cross-presentation of ovalbumin using a number of models. Our findings indicate that calreticulin does not enhance in vitro cross-presentation of an ovalbumin-derived peptide, or of fused or bead-associated ovalbumin. Additionally, in vivo, calreticulin fusion or co-conjugation does not enhance the efficiency of CD8 T cell activation by soluble or bead-associated ovalbumin either in wild type mice or in mice lacking Toll-like receptor 4 (TLR4). Furthermore, we detect no significant differences in cross-presentation efficiencies of glycosylated vs. non-glycosylated forms of ovalbumin. Together, these results point to the redundancies in pathways for uptake of soluble and bead-associated antigens.