• Reproductive and Developmental Biology
• /
• v.37 no.1
• /
• pp.1-8
• /
• 2013

In order to investigate genetic stability and gene expression profile after cloning procedure, two groups of cloned pigs were used for swine leukocyte antigen (SLA) gene nucleotide alteration and microarray analyses. Each group was consist of cloned pigs derived from same cell line (n=3 and 4, respectively). Six SLA loci were analyzed for cDNA sequences and protein translations. In total, 16 SLA alleles were identified and there were no evidence of SLA nucleotide alteration. All SLA sequences and protein translations were identical among the each pig in the same group. On the other hand, microarray assay was performed for profiling gene expression of the cloned pigs. In total, 43,603 genes were analyzed and 2,150~4,300 reliably hybridized spots on the each chip were selected for further analysis. Even though the cloned pigs in the same group had identical genetic background, 18.6~47.3% of analyzed genes were differentially expressed in between each cloned pigs. Furthermore, on gene clustering analysis, some cloned pigs showed abnormal physiological phenotypes such as inflammation, cancer or cardiomyopathy. We assumed that individual environmental adaption, sociality and rank in the pen might have induced these different phenotypes. In conclusion, the results of the present study indicate that SLA locus genes appear to be stable following SCNT. However, gene expressions and phenotypes between cloned pigs derived from the same cell line were not identical even under the same rearing conditions.

• Hanyang Medical Reviews
• /
• v.33 no.1
• /
• pp.10-16
• /
• 2013

Follicular helper T cells (Tfh) play a significant role in providing T cell help to B cells during the germinal center reaction, where somatic hypermutation, affinity maturation, isotype class switching, and the differentiation of memory B cells and long-lived plasma cells occur. Antigen-specific T cells with IL-6 and IL-21 upregulate CXCR5, which is required for the migration of T cells into B cell follicles, where these T cells mature into Tfh. The surface markers including PD-1, ICOS, and CD40L play a significant role in providing T cell help to B cells. The upregulation of transcription factor Bcl-6 induces the expression of CXCR5, which is an important factor for Tfh differentiation, by inhibiting the expression of other lineage-specific transcription factors such as T-bet, GATA3, and RORγt. Surprisingly, recent evidence suggests that CD4 T cells already committed to Th1, Th2, and Th17 cells obtain flexibility in their differentiation programs by downregulating T-bet, GATA3, and RORγt, upregulating Bcl-6 and thus convert into Tfh. Limiting the numbers of Tfh within germinal centers is important in the regulation of the autoantibody production that is central to autoimmune diseases. Recently, it was revealed that the germinal center reaction and the size of the Tfh population are also regulated by thymus-derived follicular regulatory T cells (Tfr) expressing CXCR5 and Foxp3. Dysregulation of Tfh appears to be a pathogenic cause of autoimmune disease suggesting that tight regulation of Tfh and germinal center reaction by Tfr is essential for maintaining immune tolerance. Therefore, the balance between Tfh and Tfr appears to be a critical peripheral tolerance mechanism that can inhibit autoimmune disorders.

• IMMUNE NETWORK
• /
• v.22 no.6
• /
• pp.50.1-50.19
• /
• 2022

Autoreactive B cells are not entirely deleted, but some remain as immunocompetent or anergic B cells. Although the persistence of autoreactive B cells as anergic cells has been shown in transgenic mouse models with the expression of B cell receptor (BCR) reactive to engineered self-antigen, the characterization of naturally occurring anergic B cells is important to identify them and understand their contribution to immune regulation or autoimmune diseases. We report here that a low-level expression of CD138 in the splenic B cells marks naturally arising anergic B cells, not plasma cells. The CD138^int B cells consisted of IgM^lowIgD^high follicular (FO) B cells and transitional 3 B cells in homeostatic conditions. The CD138^int FO B cells showed an anergic gene expression profile shared with that of monoclonal anergic B cells expressing engineered BCRs and the gene expression profile was different from those of plasma cells, age-associated B cells, or germinal center B cells. The anergic state of the CD138^int FO B cells was confirmed by attenuated Ca²⁺ response and failure to upregulate CD69 upon BCR engagement with anti-IgM, anti-IgD, anti-Igκ, or anti-IgG. The BCR repertoire of the CD138^int FO B cells was distinct from that of the CD138^- FO B cells and included some class-switched B cells with low-level somatic mutations. These findings demonstrate the presence of polyclonal anergic B cells in the normal mice that are characterized by low-level expression of CD138, IgM downregulation, reduced Ca²⁺ and CD69 responses upon BCR engagement, and distinct BCR repertoire.

• Journal of Veterinary Clinics
• /
• v.6 no.2
• /
• pp.307-318
• /
• 1989

In recent years much attention has been paid to swine respiratory infection caused by Pasteurella(P) multocida with rapid expansion of pork Industry in Korea. The present study was performed to observe the etiologic situation of P. multocida infection by bacteriological, serological(serotyping) and pathological examinations with the lungs respectively. In addition antibiotic susceptibility test was carried out against the isolated strains of P. multocida. The results obtained are as follows : 1. Eighteen strains(12.8％) wert isolated from the 140 cases of swine lungs examined, and biological and biochemical characteristics of the isolates were the sam as those in the references of other workers, whereas some differences were observed in sugar fermentation and enzyme activity according to the strain of isolates. 2. Capsular serotyping performed on 18 P. multocida revealed that 13 strains(72.2％) were A type and 5 strains(27.8％) were D type, respectively. 3. When serotyping was performed against somatic antigen on 18 strains capsular types of which were identified as described above 9(50％), 3(16.7％) and 4(22.2％) strains belong to 1:A, 3:A and 2:D, respectively, but untypable 2 strains(11.1％) were observed. 4. Antibiotic susceptibility test by employing disc method for 24 kinds of drugs revealed that 15 kinds of antibiotics were sensitive to 18 strains of P. multocida isolated such as ampicillin(l00％), penicillin(100％), cloxacillin(56％), piperacillin(70％), cefotaxime(30%), minocycline(60％), chloramphenicol(95％), erythromycin(39％), kanamycin(17％), gentamicin(70%), amikasin(30%), colistin(78％) and nalidixic acid(5％), respectively, but resistant to 9 kinds of antibiotics such as sulpenicillin, cefazolin, cephalothin, cefametazol, cefoperazone, kitasamycin, oleandomycin. lincomycin and bacitracin. 5. Pathological features of 60 cases of swine lungs indicated that pneumonic .lesions were observed in 38 cases(63.3％) examined by macroscopic finding, in which lesions of 8 cases(13.4％) would correspond to those of mycoplasmal infection, and 30 cases(50％) were similar to viral infection by histopathological finding, whereas 22 cases(36.7％) were considered to be normal by ecropsy or histopathological finding.

• IMMUNE NETWORK
• /
• v.21 no.5
• /
• pp.34.1-34.16
• /
• 2021

Sjögren's syndrome (SS) is an autoimmune disease characterized by dryness of the mouth and eyes. The glandular dysfunction in SS involves not only T cell-mediated destruction of the glands but also autoantibodies against the type 3 muscarinic acetylcholine receptor or aquaporin 5 (AQP5) that interfere with the secretion process. Studies on the breakage of tolerance and induction of autoantibodies to these autoantigens could benefit SS patients. To break tolerance, we utilized a PmE-L peptide derived from the AQP5-homologous aquaporin of Prevotella melaninogenica (PmAqp) that contained both a B cell "E" epitope and a T cell epitope. Repeated subcutaneous immunization of C57BL/6 mice with the PmE-L peptide efficiently induced the production of Abs against the "E" epitope of mouse/human AQP5 (AQP5E), and we aimed to characterize the antigen specificity, the sequences of AQP5E-specific B cell receptors, and salivary gland phenotypes of these mice. Sera containing anti-AQP5E IgG not only stained mouse Aqp5 expressed in the submandibular glands but also detected PmApq and PmE-L by immunoblotting, suggesting molecular mimicry. Characterization of the AQP5E-specific autoantibodies selected from the screening of phage display Ab libraries and mapping of the B cell receptor repertoires revealed that the AQP5E-specific B cells acquired the ability to bind to the Ag through cumulative somatic hypermutation. Importantly, animals with anti-AQP5E Abs had decreased salivary flow rates without immune cell infiltration into the salivary glands. This model will be useful for investigating the role of anti-AQP5 autoantibodies in glandular dysfunction in SS and testing new therapeutics targeting autoantibody production.