中职卫校病免学教学中合作学习的探究

合作学习是新课程倡导的有效的学习方式之一。与传统的教学组织形式相比，合作学习有较多的优越性，但在教学中仍存在一些有待探讨和解决的问题。本文就合作学习在病免学的教学实践中存在的相关问题进行探究，并提出一些见解。

智慧课堂教学模式在《病原生物学与免疫学基础》实训教学中的应用

目的评价智慧课堂教学模式在《病原生物学与免疫学基础》(以下简称《免病学》)实训教学中的应用效果。方法随机抽取本院2017级护理专业两个班学生作为研究对象,其中一个班30人作为对照组,另一个班30人作为实验组。实验组采用智慧课堂教学模式,对照组采用传统课堂教学模式,以实训操作技能考试对两组学生的学习效果进行分析,以问卷调查法了解实验组学生对智慧课堂教学模式的评价。结果实验组学生的实训操作技能考试成绩要优于对照组,差异有统计学意义(P<0.05)。实验组学生认为智慧课堂教学模式有助于激发学习兴趣,提升实训能力,改善学习效果。结论应用智慧课堂教学模式能有效促进《免病学》实训教学,激发学生学习兴趣,提升教学质量。

提高“免疫学基础及病原生物学”教学效果的实践和体会

本文探讨了如何提高免疫学基础及病原生物学教学效果的方法：上好起始课，激发学生的求知欲；精讲启发、激发兴趣；用形象比喻理解助记；采用多种教具，多种教法相结合，变抽象为具体；投以情感，使课堂气氛变得有声有色等。

Immunologic pathogenesis of multiple sclerosis

Multiple sclerosis （MS） is an autoimmune disease. The etiology and pathogenesis of MS remain unclear. At present, there are substantial evidences to support the hypothesis that genetics plays a crucial role. The people who have genetic predisposing genes easily develop immune-mediated disorder, probably in conjunction with environmental factors. The aim of this review is to describe recent observations regarding the immunologic pathogenesis of MS.

Alterations of red blood cell immunoadherence function in hepatitis B patients

AIMS To investigate the alterations of RBC immunoadherence function in patients with various hepatitis B. METHODS RBCC3bRR,RBCICRR and serum CIC levels were measured in 42 patients with acute and chronic hepatitis B at ac- tive and convalescence stages. RESULTS RBCC3bRRs at the active/acute stage of various hepatitis were decreased.They were 13,54%±5,23% in AH, 7.61%±4.12% in AFH,and 16.18%±6.10% in CH, respectively,all of which were lower than those in normal persons (18.12%±3.91% ).At the quiescent/recovery stage of various hepatitis,the RBCC3bRRs were increased significantly.The changes of RBCICRR and serum CIC level were contrary to those of RBCC3bRR. CONCLUSIONS RBC immunoadherence function is decreased in acute and chronic hepatitis.The decrease is in direct proportion to the severity of the diseases.

Expression of Porcine Reproductive and Respiratory Syndrome Virus ORF7 Gene and Purification and Immunological Activity Analysis of the Recombinant Protein

[Objective] The aim of this study was to realize efficient expression of the porcine reproductive and respiratory syndrome virus （PRRSV） ORF7 gene in genetic engineering bacteria and analYze the immunological activity of the recombinant protein after purification. [ Method] The constructed recombinant expression vector pET-ORF7 was transformed into Escherichia co1BL21 （DE3） and induced by IPTG under the optimal condition. After analysis of SDS-PAGE and Western Blot, the expression products were purified by Ni-NTA His · Bind Resin chrom- atographic column under denaturing condition and renatured by gradient dialysis. Subsequently, the immunological activity of the renatured recombinant protein was detected by Westem Blot and indirect ELISA. [ Result] The recombinant plasmid pET-ORF7 expressed in E. coli successfully, and the fusion protein was in the form of inclusion body. By SDS-PAGE detection, the molecular weight of the expression protein was approximate 33 kD, according with the expectation. Analysis by Bandscan software showed that the expressed fusion protein was about 50% of total bacterial protein of BL21 （DE3）. Wastem Blot and indirect ELISA detection showed that the renatured protein could react with PRRSV positive serum specifically, indicating its good immunological activity. [ Conclusion] This study lays a foundation for the preparation of PRRSV monoclonal antibody and diagnostic kit.

Clinico-pathologic significance of neuroendocrine cells in gastric carcer tissue

AIMS To elucidate the biological and clinicopathological signifi- cance of neuroendocrine(NE)cells in gastric carcinoma(GC). METHODS One hundred and eighty-nine cases of various histo- logical types of GC were observed using light microscopy, histochemistry,immunohistochemistry and electron microscopy. Of them 127 patients were followed up. RESULTS Chromogranin A(CgA)positive GC was demonstrat- ed in 85 cases(45.0%).The typos of NE cells in GC were probed using 9 kinds of hormone antibodies 49 cases(67.2%) contained more than one hormone.NE cells were found more often in poorly differentiated GC than in well differentiated ones(P<0. 01).Expression of some kinds of hormone Was relative to the dif- ferentiation and histological types of GC.BOM,CT(P<0.01) GAST and 5-HT(P<0.05)were more expressed in poorly differ- entiated cases than in well defferentiated ones.Nineteen cases of the matastatic foci in regional lymph nodes were found to have CgA positive cancer cells.The presence of HCG in matastatic lymph nodes was more often observed than that of other hormone (P<0.01).The survival rate of patients with NE positive GC was 38.9% and negative GC 52.7%.Five of 7 patients(71. 4%)with somatostatin positive GC still survived at follow up of 33-66 months,but 4 patients with HCG positive GC died in 12-29 months. CONCLUSIONS The NE cells occur more frequently in poorly differentiated GC.Certain hormones appear to be related to the metastasis and prognosis.

Location of Highly Pathogenic Porcine Reproductive and Respiratory Syndrome Virus in Tissues of Natural Cases

[ Objective] The aim of this study was to provide a theoretical basis for the prevention and treatment of highly pathogenic porcine reproductive and respiratory syndrome （HP-PRRS）. [Method] Antigen location and histopathological observation in natural cases infected by highly pathogenic porcine reproductive and respiratory syndrome virus （HP-PRRSV） were analyzed by immunohistochemistry and H. E. staining. [Result] The virus antigen mainly existed in epithelial calls, and also a few in mecrophages, lymphocytes and brain nerve cells. [ Conclusion] The cell and tissue tropism of HP-PRRSV strain in natural cases is different from that of previous strains.

Crohn's disease in Stockholm County during 1990-2001:An epidemiological update

AIM： To further assess of the incidence and localization of Crohn＇s disease （CD） in a well-defined population during the 1990s and to evaluate the prevalence of CD on the 1^st of January 2002. METHODS： In a retrospective population based study, all 16-90 years old citizens of Stockholm County diagnosed as having CD according to Lennard Jones＇ criteria between 1990 and 2001 were included. Case identification was made by using computerized inpatient and outpatient registers. Moreover private gastroenterologists were asked for possible cases. The extent of the disease and the frequency of anorectal fistulae were determined as were the ages at diagnosis. Further, the prevalence of CD on the 1^st of January 2002 was assessed. RESULTS： All the 1 389 patients, 689 men and 700 women, fulfilled the criteria for CD. The mean incidence rate for the whole period was 8.3 per 10s （95%CI 7.9 -8.8）. There was no difference between the genders. The mean annual incidence of the whole study period for colorectal disease and ileocecal disease, was 4.4 （95%CI 4.0-4.7） and 2.4 （95%CI 2.1-2.6） per 10s, respectively. Perianal disease occurred in 13.7% （95%CI 11.9-15.7 %） of the patients. The prevalence of CD was 213 per 100 000 inhabitants. CONCLUSION： The incidence of CD has markedly increased during the last decade in Stockholm County and 0.2% of the population suffers from CD. The increase is attributed to a further increase of colorectal disease, while the incidence of ileocecal disease has remained stable.

Do we really understand what the immunological disturbances in inflammatory bowel disease mean?

The gastrointestinal tract uses a system of tolerance and controlled inflammation to limit the response to dietary or bacteria-derived antigens in the gut. When this complex system breaks down, either by a chemi- cal or pathogenic insult in a genetically predisposed individual the resulting immune response may lead to inflammatory bowel disease. Although the aetio- pathogenesis of inflammatory bowel disease remains unsolved current evidence indicates that defective T-cell apoptosis and impairment of intestinal epithelial barrier function play important roles. In inflammatory bowel disease, it has been reported that activation of macrophages seems to be as important as increased production of the macrophage-derived cytokines such as TNF-α, IL-1 and IL-6. The triggering factor for this cascade is still to be elucidated as to whether it rep- resents an auto-antigen or a hetero-antigen. It has been also demonstrated that a serologic anti-microbial response exists. This response includes antibodies against saccharomyces cerevisiae （ASCA）, E. coli outer membrane porin C （Omp-C）, flagelin （cBirl） and pseu- domonas aeroginosa （I2）. Host response to microbial pathogens includes self-defense mechanisms including defensins, pattern recognition receptors and Toll-like receptors. Neuroimmunomodulation in inflammatory bowel disease （IBD） is another interesting approach with implications on the influence of brain-gut axis on intestinal inflammation and its perpetuation. It isprobable that inflammatory bowel disease represents a heterogenic group of diseases that share similar mechanisms of tissue damage but have different ini- tiating events and immunoregulatory abnormalities. A better understanding of all these events will hope- fully provide new insights into the mechanisms of epithelial responses to microorganisms and ideas for therapies.

Gastric malignancies in Northern Jordan with special emphasis on descriptive epidemiology

AIM:To study the epidemiology of gastric malignancies in Jordan as a model for Middle East countries where such data is scarce. METHODS:Pertinent epidemiological and clinicopathological data for 201 patients with gastric malignancy in north of Jordan between 1991 and 2001 were analyzed. RESULTS:Male:female ratio was 1.8:1.The mean age was 61.2 years,and 8.5% of the patients were younger than 40 years of age.The overall age-adjusted incidence was 5.82/100 000 population/year.The age specific incidence for males raised from 1.48 in those aged 30-39 years to 72.4 in those aged 70-79 years.Adenocarcinomas, gastric lymphomas,malignant stromal tumors,and carcinoids were found in 87.5%,8%,2.5%,and 2% respectively.There was an average of 10.1-month delay between the initial symptoms and the diagnosis.Only 82 patients underwent“curative”gastrectomy.Among adenocarcinoma groups,Lauren intestinal type was the commonest(72.2%)and the distal third was the most common localization(48.9%).The mean follow up for patients with gastric adenocarcinoma was 25.1 mo(range 1-132mo).The 5-year survival rates for stages Ⅰ(n=15), Ⅱ(n=41),Ⅲ(n=59),and Ⅳ(n=53) were 67.3%,41.3%, 5.7%,and 0% respectively(P=0.0001).The overall 5 year survival was 21.1%. CONCLUSION:Despite low inddence,some epidemiological features of gastric cancer in Jordan mimic those of high- risk areas.Patients are detected and treated after a relatively long delay.No justification in favor of a possible gastric cancer screening effort in Jordan is supported by our study;rather,the need of an earlier diagnosis and subsequent better care.

Human bocavirus: Current knowledge and future challenges

Human bocavirus(HBoV) is a parvovirus isolated about a decade ago and found worldwide in both respiratory samples, mainly from early life and children of 6-24 mo of age with acute respiratory infection, and in stool samples, from patients with gastroenteritis. Since then, other viruses related to the first HBoV isolate(HBoV 1), namely HBoV 2, HBoV 3 and HBoV 4, have been detected principally in human faeces. HBo Vs are small nonenveloped single-stranded DNA viruses of about 5300 nucleotides, consisting of three open reading frames encoding the first two the non-structural protein 1(NS1) and nuclear phosphoprotein(NP1) and the third the viral capsid proteins 1 and 2(VP1 and VP2). HBoV pathogenicity remains to be fully clarified mainly due to the lack of animal models for the difficulties in replicating the virus in in vitro cell cultures, and the fact that HBo V infection is frequently accompanied by at least another viral and/or bacterial respiratory and/or gastroenteric pathogen infection. Current diagnostic methods to support HBoV detection include polymerase chain reaction, real-time PCR, enzymelinked immunosorbent assay and enzyme immunoassay using recombinant VP2 or virus-like particle capsid proteins, although sequence-independent amplification techniques combined with next-generation sequencing platforms promise rapid and simultaneous detection of the pathogens in the future. This review presents the current knowledge on HBoV genotypes with emphasis on taxonomy, phylogenetic relationship and genomic analysis, biology, epidemiology, pathogenesis and diagnostic methods. The emerging discussion on HBoV s as true pathogen or innocent bystander is also emphasized.

Extremely well-differentiated adenocarcinoma of the stomach: Clinicopathological and immunohistochemical features

AIM： Minimal deviation carcinoma of the uterine cervix, otherwise known as extremely well-differentiated adenocarcinoma （EWDA）, is characterized by its benign microscopic appearance in contrast to its aggressive behavior. In order to elucidate the clinicopathological features and biological behavior of the gastric counterpart of EWDA, we, using immunohistochemistry, analyzed nine lesions for the phenotypic expression, proliferative activity, and the expression of oncogene-associated products. METHODS： Clinicopathological features, including preoperative biopsy diagnosis, were reviewed. Using immunohitstochemistry, Ki-67 labeling index and expression of p53 and c-erbB-2 protein in the gastric lesions were detected.RESULT： Locations in the middle or upper third of the stomach and polypoid macroscopic features are characteristic of EWDA of the stomach. Although 4 of the 9 lesions showed only focal lymphatic or venous invasion, lymph node metastasis was not present and none of the patients died of the lesions （mean follow-up period, 56 too）. All 9 cases of EWDA could be classified into gastric phenotype （5 lesions） and intestinal phenotype （4 lesions）. The former resembled gastric foveolar epithelium, mucous neck cells or pyloric glands, but their papillary structures were frequently elongated and the tumor cellsand their nuclei were slightly larger and more hyperchromatic compared to normal epithelium. The latter resembled intestinal metaplasia with minimal nulcear atypia and irregular glands; two of these lesions demonstrated complete intestinal phenotype, while two demonstrated incomplete intestinal phenotype. Ki-67 labeling index was low and none of the cases revealed over-expression of p53 and c-erbB-2 protein. CONCLUSION： Unlike minimal deviation carcinoma of the cervix, these findings suggest that EWDA of the stomach is a lesion of low-grade malignancy. This favorable biological behavior is supported by the data of a low Ki-67 labeling index and a lack of p53 or c-erbB-2 protein over-expression. Because of its resemblance to normal gastric mucosa or mucosa with intestinal metaplasia, EWDA is often misdiagnosed. To prevent the misdiagnosis of such lesions, the clinical and pathologic characteristics should be taken into consideration.

CXCL16 participates in pathogenesis of immunological liver injury by regulating T lymphocyte infiltration in liver tissue

AIM： To investigate the role of CXCL16 in the pathogenesis of immunological liver injury and to explore the possible mechanism ofT lymphocyte infiltration regulated by CXCL16. METHODS： Immunological liver injury in murine model was induced by Bacille Calmette-Guerin and lipopolysaccharide. Expression pattern and distribution of CXCL16 were examined by real-time quantitative RT-PCR and immunohistochemical analysis. Anti-CXCL16 antibody was administrated in vivo to investigate its effect on T-cell recruitment and acute hepatic necrosis. The survival of murine model was also evaluated. RESULTS, The murine immunological liver injury model was successfully established, CXCL16 expression increased and predominantly distributed in periportal areas and vascular endothelia in injured liver tissues. Administration of anti-CXCL16 Ab protected the mice from death and acute liver damage. Approximately 70% of the mice survived for 72 h in the anti-CXCL16 Ab treatment group, whereas 80% died within 72 h in control Ab group. The number of liver-infiltrating T lymphocytes was significantly reduced from 1.01×10^7 to 3.52×10^6/liver, compared with control Ab treatment. CONCLUSION： CXCL16 is involved in immunological liver injury by regulating T lymphocyte infiltration in liver tissue.

Antiviral innate immunity pathways

Recent studies have uncovered two signaling pathways that activate the host innate immunity against viral infection. One of the pathways utilizes members of the Toll-like receptor （TLR） family to detect viruses that enter the endosome through endocytosis. The TLR pathway induces interferon production through several signaling proteins that ultimately lead to the activation of the transcription factors NF-kB, IRF3 and IRFT. The other antiviral pathway uses the RNA helicase RIG-Ⅰ as the receptor for intracellular viral double-stranded RNA. RIG-Ⅰ activates NF-kB and IRFs through the recently identified adaptor protein MAVS, a CARD domain containing protein that resides in the mitochondrial membrane. MAVS is essential for antiviral innate immunity, but it also serves as a target of Hepatitis C virus （HCV）, which employs a viral protease to cleave MAVS off the mitochondria, thereby allowing HCV to escape the host immune system.

Alteration of chaperonin60 and pancreatic enzyme in pancreatic acinar cell under pathological condition

AIM： To investigate the changes of chaperonin60 （Cpn60） and pancreatic enzymes in pancreatic acinar cells, and to explore their roles in the development of experimental diabetes and acute pancreatitis （AP）. METHODS： Two different pathological models were replicated in Sprague-Dawley rats： streptozotocininduced diabetes and sodium deoxycholate-induced AP. The contents of Cpn60 and pancreatic enzymes in different compartments of the acinar cells were measured by quantitative immunoo/tochemistry. RESULTS： The levels of Cpn60 significanUy increased in diabetes, but decreased in AP, especially in the zymogen granules of the pancreatic acinar cells. The elevation of Cpn60 was accompanied with the increased levels of pancreatic lipase and chymotrypsinogen in diabetes. However, a decreased Cpn60 level was accompanied by high levels of lipase and chymotrypsinogen in AP. The amylase level was markedly reduced in both the pathological conditions. CONCLUSION： The equilibrium between Cpn60 and pancreaUc enzymes in the acinar cells breaks in AP, and Cpn60 content decreases, suggesting an insufficient chaperone capacity. This may promote the aggregation and autoactivation of the premature enzymes in the pancreatic acinar cells and play roles in the development of AR

Expression of pituitary homeobox 1 gene in human gastric carcinogenesis and its clinicopathological significance

AIM： To investigate the effect of pituitary homeobox 1 （PITX1） expression in cases of human gastric cancer on cancer differentiation and progression, and carcinogenesis. METHODS： Using polyclonal PITX1 antibodies, we studied the expression of PITX1 in normal gastric mucosa, atypical hyperplasia, intestinal metaplasia, and cancer tissue samples from 83 gastric cancer patients by immunohistochemistry. Moreover, semi-reverse transcription polymerase chain reaction （semi-RT-PCR） was performed to detect the mRNA level of PITX1 in three gastric cancer cell lines and a normal gastric epithelial cell line. Subsequently, somatic mutations of the PITX1 gene in 71 gastric cancer patients were analyzed by a combination of denaturing high performance liquid chromatography （DHPLC） and DNA sequencing. RESULTS： Immunohistochemistry showed that PITXl was strongly or moderately expressed in the parietal cells of normal gastric mucosa （100%）, while 55 （66.3%） out of 83 samples of gastric cancers showed decreased PITXl expression. Moreover, PITXl expression was reduced in 20 out of 28 cases （71.5%） of intestinal metaplasia, but in only 1 out of 9 cases （11%） of atypical hyperplasia. More importantly, PITXl expression was significantly associated with the differentiation, position and invasion depth of gastric cancers （r = -0.316, P 〈 0.01; r = 0.213, P 〈 0.05; r = -0.259, P 〈 0.05, respectively）. Similarly, levels of PITXl mRNA were significantly decreased in 2 gastric cancer cell lines, BGC-823 and SGC-7901, compared with the normal gastric epithelial cell line GES-1 （0.306 ± 0.060 vs 0.722 ± 0.102, P 〈 0.05; 0.356 ± 0.081 vs 0.722 ± 0.102, P 〈 0.05, respectively）. Nevertheless, no somatic mutation of PITX1 gene was found in 71 samples of gastric cancer by DHPLC analysis followed by sequencing. CONCLUSION： Down-regulation of PITX1 may be a frequent molecular event in gastric carcinogenesis. Aberrant levels of PITXl expression may be closely correlated with the progression and differentiation of gastric cancer,

Science Letters:A synthetic Toll-like receptor 2 ligand decreases allergic immune responses in a mouse rhinitis model sensitized to mite allergen

It has been proposed that activation of Toll-like receptors （TLRs） plays crucial roles in the polarization of adaptive immune responses. A synthetic Toll-like receptor 2 （TLR2） ligand, Pam3CSK4, has been reported to modulate the balance of Th1/Th2 responses. We evaluated the modulation effect of Pam3CSK4 on allergic immune response in a mouse rhinitis model sensitized to house dust mite allergen （HDM）. Mice were sensitized and challenged with Dermatophagoidesfarinae allergen （Der f）, and then the allergic mice were treated by Pam3CSK4. Nasal allergic symptoms and eosinophils were scored. Der f-specific cytokine responses were examined in the splenocytes and bronchoalveolar lavage fluid （BALF）. Serum level of total IgE was also detected. After establishing a mouse allergic rhinitis model with HDM, we have showed that Pam3CSK4 treatment not only ameliorated the nasal allergic symptoms remarkably but also decreased the eosinophils and total inflammation cells in BALF significantly. Analysis of cytokine profile found that IFN-7 released from either BALF or stimulated splenocytes increased markedly in Pam3CSK4-treated mice, while IL-13 decreased significantly. Moreover, serum level of total IgE was significantly lower in Pam3CSK4-treated mice than in the untreated. Thus, in an allergic rhinitis mouse model developed with HDM, Pam3CSK4 was shown to exhibit an antiallergic effect, indicating its potential application in allergic diseases.

Expression transformation of claudin-1 in the process of gastric adenocarcinoma invasion

AIM: To investigate the relation of expression transfor-mation of claudin-1 with invasiveness and metastasis of gastric carcinoma. METHODS: By using immunohistochemistry, expres-sion of claudin-1 in mucosa and invasive front of 136 gastric adenocarcinoma cases and proliferative index (Ki-67) were detected and analyzed. RESULTS: In mucosa, the claudin-1 over-expression rate of mucinous adenocarcinomas (including signet-ring cell carcinomas) was the highest. It was nega-tively related with the differentiation but positively related with the invasiveness and metastasis of gastric cancer. In invasive front, the claudin-1 over-expression rate was positively related with the differentiation, in-vasiveness and metastasis of gastric carcinoma. The expression transformation of claudin-1 was found in gastric carcinoma. The expression of claudin-1 in inva-sive front was transformed in 28/136 gastric carcinoma cases. The transformation rate in highly differentiated tubular adenocarcinomas was the highest (51.5%, 17/33). The deeper was the invasiveness, the higher was the transformation rate. The claudin-1 expression transformation rate in serosa and omenta was signifi -cantly higher (92.9%) than in tunica muscularis of in-vasive gastric cancer cases, as well as in patients withlymph node metastasis than in those without lymph node metastasis. CONCLUSION: Up-regulation of claudin-1 expres-sion and its transformation in invasive and metastatic gastric carcinoma suggest that claudin-1 participates in the transformation of biological behaviors in neo-plasms. Further study is needed to elucidate the pre-cise mechanism and the relation of claudin-1 expres-sion with the neoplasm progress.

Changes of CD8+CD28-T regulatory cells in rat model of colitis induced by 2,4-dinitrofluorobenzene

AIM:To determine the changes of CD8+ T subsets especially CD8+CD28-T regulatory cells in rat model of experimental colitis induced by 2,4-dinitrofluorobenzene (DNFB). METHODS:The rat model of experimental colitis was induced by enema with DNFB.Ten days later,colonic intraepithelial and splenic lymphooltes were isolated from colitis animals (n=16) and controls (n=8).The proportion of CD8+ T cells,CD8+CD28+ T cells and CD8+CD28-T regulatory cells were determined by flow cytometry. RESULTS:The model of experimental colitis was successfully established by DNFB that was demonstrated by bloody diarrhea,weight loss and colonic histopathology.The proportion of CD8+ T cells in either splenic or colonic intraepithelial lymphocytes was not significantly different between colitis animals and controls (spleen:34.6±7.24 % vs 33.5±9.41%, colon:14.0±8.93 % vs 18.0±4.06 %,P>0.05).But CD8+CD28- T regulatory cells from colitis animals were significantly more than those from controls (spleen:11.3±2.26 % vs 5.64±1.01%, colon:6.50±5.37 % vs 1.07±0.65 %,P<0.05).In contrast, CD8+CD28+ T cells from colitis animals were less than those from controls (spleen:23.3±6.14 % vs 27.8±9.70 %,P=0.06; colon:7.52±4.18 % vs 16.9±4.07 %,P<0.05).The proportion of CD8+CD28-T regulatory cells in splenic and colon intraepithelial CD8+ T cells from colitis animals was higher than that from controls (spleen:33.3±5.49 % vs 18.4±7.26 %, colon:46.0±14.3 % vs6.10±3.72 %,P<0.005). CONCLUSION:Experimental colitis of rats can be induced by DNFB with simplicity and good reproducibility.The proportion of CD8+CD28-T regulatory cells in rats with experimental colitis is increased,which may be associated with the pathogenesis of colitis.