Fanzhi Kong

Differentiation Imbalance of Th1/ Th17 in Peripheral Blood Mononuclear Cells Might Contribute to Pathogenesis of Hashimoto’s Thyroiditis

T helper 17(Th17) cell is a new subset of CD4+ T cells that produce a proinflammatory cytokine interleukin‐17 (IL‐17). Th17 cells have recently been shown to play a critical role in many autoimmune diseases that had previously been thought to be Th1 dominant. Although Hashimoto’s thyroiditis (HT) was thought to be a Th1‐type disease, the contributions of Th17 cells to the pathogenesis remain unclear. In this study, we investigated the expression levels of Th1/Th17 cell‐associated factors in peripheral blood mononuclear cells (PBMC) and plasma from patients with HT by quantitative real‐time polymerase chain reaction (RT‐qPCR) and enzyme‐linked immunosorbent assay (ELISA). Our results showed that the expression levels of Th1 cells‐related T‐bet and interferon‐γ (IFN‐γ) mRNA in PBMC from HT significantly decreased. However, the mRNA of Th17 coherent retinoic acid‐related orphan nuclear receptor gamma t (RORγt) and IL‐17 in patients with HT increased. In addition, a negative correlation between T‐bet and RORγt mRNA expression was found in patients with HT, and the similar phenomena also appeared on the levels of mRNA and plasma concentration between IFN‐γ and IL‐17. It suggested that Th17 cells rather than Th1 cells predominated among patients suffering from HT, and Th17 cells might be involved in the pathogenesis of HT.

Four novel resistance integron gene-cassette occurrences in bacterial isolates from zhenjiang, china.

Integrons, which are widely distributed among bacteria and are strongly associated with resistance, are specialized genetic elements that are capable of capturing, integrating, and mobilizing gene cassette. In this work, we investigated classes 1, 2, and 3 integrons associated integrases genes in 365 bacteria isolates, amplified and analyzed the structure of class 1 integron, detected 8 resistant gene cassettes [dfr17, aadA5, aadA1, aadA2, dhfrI, aadB, aac(6′)-II, and pse-I], and found four novel gene-cassette arrays. We also found that commensal bacteria in the common microenvironment had the same integron gene cassette, which provided direct evidence that integron was an important horizontal transmission element.

The mutations of Th1 cell-specific T-box transcription factor may be associated with a predominant Th2 phenotype in gastric cancers

Gastric cancer is a serious public health cancer and causes nearly 1 million deaths a year worldwide. Th1 cells play critical roles in orchestrating the adaptive immune responses against gastric cancer. T‐bet, a member of the T‐box family of transcription factors, is the Th1 master regulator and up‐regulated during Th1 differentiation. Polymorphisms have also been shown to exist in T‐bet. Some reports indicated that some tumours were associated with the drift of Th1 and Th2. In the present work, we investigated the drift of Th1/Th2 by detecting the expression levels of T‐bet, IFN‐γ, IL‐4, and GATA‐3 in peripheral blood mononuclear cell of gastric cancer patients by real‐time PCR, explored the relationship between the polymorphism of T‐bet gene and drift of Th1/Th2 by gene sequence, western blot, and gene transfection. Our results indicated that a predominant Th2 phenotype was existence. T‐bet gene mutations may be associated with Th2‐dominated condition in gastric cancers.

Enhancing Specific-Antibody Production to the ragB Vaccine with GITRL That Expand Tfh, IFN-γ+ T Cells and Attenuates Porphyromonas gingivalis Infection in Mice

The outer membrane protein RagB is one of the major virulence factors of the periodontal pathogen Porphyromonas gingivalis (P. gingivalis). In order to induce protective immune response against P. gingivalis infection, an mGITRL gene-linked ragB DNA vaccine (pIRES-ragB-mGITRL ) was constructed. Six-week-old female BALB/c mice were immunized with pIRES-ragB-mGITRL through intramuscular injection and then challenged by subcutaneous injection in the abdomen with P. gingivalis. RagB-specific antibody-forming cells were evaluated by an Enzyme-linked immunosorbent spot, and specific antibody was determined by enzyme-linked immunosorbent assay. In addition, the frequencies of Tfh and IFN-γ+ T cells in spleen were measured using flow cytometer, and the levels of IL-21 and IFN-γ mRNA or proteins were detected by real time RT-PCR or ELISA. The data showed that the mGITRL-linked ragB DNA vaccine induced higher levels of RagB-specific IgG in serum and RagB-specific antibody-forming cells in spleen. The frequencies of Tfh and IFN-γ+ T cells were obviously expanded in mice immunized by pIRES-ragB-mGITRL compared with other groups (pIRES or pIRES-ragB ). The levels of Tfh and IFN-γ+ T cells associated cytokines were also significantly increased in pIRES-ragB-mGITRL group. Therefore, the mice immunized with ragB plus mGITRL showed the stronger resistant to P. gingivalis infection and a significant reduction of the lesion size caused by P. gingivalis infection comparing with other groups. Taken together, our findings demonstrated that intramuscular injection of DNA vaccine ragB together with mGITRL induced protective immune response dramatically by increasing Tfh and IFN-γ+ T cells and antibody production to P. gingivalis.

The rag locus of porphyromonas gingivalis might arise from bacteroides via horizontal gene transfer

Porphyromonas gingivalis is regarded as one of the risk factors of periodontitis. P. gingivalis exhibits a wide variety of genotypes. Many insertion sequences (ISs), located in their chromosomes, made P. gingivalis differentiate into virulent and avirulent strains. In this research, we investigated the prevalence of P. gingivalis in the gingival crevicular fluid (GCF) among periodontitis patients from Zhenjiang, China, detected the P. gingivalis rag locus distributions by multiplex polymerase chain reaction (PCR), and analyzed the origin of the P. gingivalis rag locus based on evolution. There were three rag locus variants co-existing in Zhenjiang. The results showed that the rag locus may be associated with severe periodontitis. This work also firstly ascertained that the rag locus might arise, in theory, from Bacteroides sp. via horizontal gene transfer.

The blaCTX-M-1 gene located in a novel complex class I integron bearing an ISCR1 element in Escherichia coli isolates from Zhenjiang, China

Sir, CTX-M enzymes include more than 60 variants belonging to five different clusters (CTX-M-1, CTX-M-2, CTX-M-8, CTX-M-9 and CTX-M-25) according to their amino acid sequence. In recent years, CTX-M enzymes have become the most prevalent extended-spectrum b-lactamases (ESBLs), both in nosocomial and in community settings. Different genetic elements might be involved in the mobilization of blaCTX-M genes, such as insertion sequences (ISs) ISEcp1, IS26 and IS903. The blaCTX-M genes have also been associated with ISCR1 (ISs common region 1, previously also called orf513), which is embedded in class 1 integrons. Class 1 integrons containing ISCR elements are known as complex class 1 integrons. They contain the classic integron structure and a second copy of the 30CS. Between the two copies of the 30CS is a 2.1 kb ISCR, as has been identified in In6, In7, In117, In34, In35 and In601, – 5 followed by a variable region that contains resistance genes, e.g. dfrA10, catII, blaDHA-1 (pSAL-1), blaCTX-M-9 or blaCTX-M-2, 5 but never blaCTX-M-1 thus far. Between 2005 and 2006, a total of 146 Escherichia coli isolates were obtained from the Affiliated People’s Hospital of Jiangsu University. ESBL production was detected in 21/146 isolates using the standard double-disc synergy test. Eighty-nine of 146 (61%) isolates were found to carry class 1 integrons of different types, and 10 of these carried complex class I integrons according to the PCR analysis. The primers were designed according to the GenBank sequence (GenBank accession numbers AF174129 and AF071413). Five of the isolates carrying a complex class 1 integron also produced an ESBL. In these five isolates, a blaCTX-M-1 gene was detected between orf513 and an IS3000 element (Figure 1). The sequence of the complex class I integron bearing a blaCTX-M-1 gene has been submitted to GenBank under accession no. EU687490. Recently, it has been suggested that ISCR1 elements were members of an extended family of IS91-like elements that can transpose adjacent DNA sequences by a mechanism termed rolling-circle transposition and are responsible for the mobilization of antibiotic resistance genes, including the blaCTX-M genes. However, this is the first report of a CTX-M-1 gene found to be associated with an ISCR element. The ISCR element is proposed to provide a powerful mechanism to mobilize antibiotic resistance genes, and, if this is the case, further spread of blaCTX-M-1 can be expected.

Role of Positive Selection in Functional Divergence of Mammalian Neuronal Apoptosis Inhibitor Proteins during Evolution

Neuronal apoptosis inhibitor proteins (NAIPs) are members of Nod-like receptor (NLR) protein family. Recent research demostrated that some NAIP genes were strongly associated with both innate immunity and many inflammatory diseases in humans. However, no similar phenomena have been reported in other mammals. Furthermore, some NAIP genes have undergone pseudogenization or have been lost during the evolution of some higher mammals. We therefore aimed to determine if functional divergence had occurred, and if natural selection had played an important role in the evolution of these genes. The results showed that NAIP genes have undergone pseudogenization and functional divergence, driven by positive selection. Positive selection has also influenced NAIP protein structure, resulting in further functional divergence.