Preparation of a polyclonal antibody against human LYZL4 and its expression in the testis / 中华男科学杂志

Objective@#To prepare a polyclonal antibody against human lysozyme-like protein 4 (LYZL4) expressed in the prokaryotic system and identify the distribution of LYZL4 in the testis.@*METHODS@#The full-length cDNA of LYZL4 was cloned into the pET32a plasmid and the expression of the recombinant LYZL4 (rLYZL4) was induced by IPTG. The rLYZL4 was purified by Ni-NTA and chitin affinity chromatography respectively and its bactericidal activity was observed by bilayer agar plate diffusion assay. The purified rLYZL4 was used as an immunogen to generate the polyclonal antibody, followed by examination of the antibody titer by ELISA and its specificity by Western blot. The distribution of LYZL4 in human tissue, sperm and seminal plasma was identified and its subcellular localization in the testis was determined by immunohistochemistry.@*RESULTS@#rLYZL4 was expressed efficiently in the prokaryotic system and exhibited no bacteriolytic activity against M. lysodeikticus and E. coli. The anti-rLYZL4 polyclonal antibody could bind the recombinant protein with a high sensitivity and specificity. LYZL4 was identified in the testis, epididymis and sperm protein extracts and localized in the acrosomal region of round and elongating spermatids.@*CONCLUSIONS@#An anti-rLYZL4 polyclonal antibody was successfully prepared using the prokaryotic expression system. LYZL4 was detected in the acrosomal region of round and elongating spermatids, suggesting an association with the structure and function of the acrosome.

Expression of human lysozyme-like protein 6 in the male reproductive system / 中华男科学杂志

<p><b>Objective</b>To study the expression of human lysozyme-like protein 6 (LYZL6) in the male reproductive system and its physiological role.</p><p><b>METHODS</b>The recombinant P. pastoris strain was cultured and induced with methanol to express LYZL6, followed by purification using chitin affinity chromatography. The bactericidal activity of the recombinant LYZL6 was observed by bilayer agar plate diffusion assay, and then the recombinant protein was used as an immunogen to generate polyclonal antibodies, whose specificity was examined by ELISA. The distribution of LYZL6 in the human tissue and semen was identified by Western blotting and the subcellular localization in the testis was investigated by immunohistochemistry.</p><p><b>RESULTS</b>At pH 5.6, recombinant LYZL6 exhibited a high bacteriolytic activity against M. lysodeikticus. ELISA analysis showed that the anti-LYZL6 polyclonal antibodies could bind the recombinant protein with a high specificity. Western blot manifested the expression of LYZL6 in the testis and epididymis, higher in the former than in the latter. LYZL6 was also detected in the sperm protein extract, while protein bands were not observed in the seminal plasma. Immunodetection with a specific antiserum localized the LYZL6 protein in the late spermatocytes and round spermatids.</p><p><b>CONCLUSIONS</b>LYZL6 has a higher bacteriolytic activity under low pH condition and is bound to spermatozoa after secreted in the testicular epithelia, suggesting that LYZL6 could act as a potential hydrolase for carbohydrates in zona pellucida penetration.</p>

Studies on the establishment of a method to detect HPV 6b E7-specific antibodies of serum and cervical secretion from patients with condyloma acuminatum and its epidemiological significance / 中华流行病学杂志

Objective To establish a method for detection of the human papi 11 omavirus(HPV)6b E7-specific antibodies in serum and cervical secretion from patients with condyloma acuminatum(CA).Methods A full-length HPV 6b E7 gene was amplified by PCR from the CA tissue to construct the recombinant plasmid pET32a(+)/HPV 6b E7.The expression of prokaryotic protein was analyzed by SDS-PAGE and Western blot,then purified with Ni-NTA Agarose affinity column and used as an diagnostic antigen for establishing indirect ELISA method,to detect specific serum IgG and specific cervical secretion slgA from 56 CA patients,81 healthy control.Sera from 43 cervical cancer was served as control.HPV 6b DNA from 56 CA patients was identified by PCR.Results Data showed that the nucleotide homology of cloned sequence was 99.5%,compared to the standard sequences of HPV 6b E7 gene(GenBank accession number:NC001355).A high level expression of E7 fusion protein was obtained in prokaryotic expression system(40 μg/ml).Based on HPV 6b E7 fusion protein being used as coating antigen,results from ELISA showed that the absorbance rates(A)of serum IgG from CA,cervix cancer and healthy control groups were 1.82±0.48,1.36 ± 0.39 and 1.39 ± 0.27,respectively.The level of IgG antibody in the serum of CA group was significantly higher than that in cervix cancer group and healthy control(P＜0.05).The A values of cervical secretion sIgA in CA and healthy control groups were 0.63 ± 0.26 and 0.53 ± 0.06,respectively,while the level of sIgA antibody in the cervical secretion of CA group was also significantly higher than that in healthy controls(P＜0.05).The positive rate of HPV 6b E7 DNA in CA tissue was 78.6%(44/56)by PCR method.When compared the results measured by PCR,the HPV 6b E7-specific IgG and sIgA antibodies by ELISA used to detect the patients infected with HPV 6b infection,showed that the sensitivity rates were 68.2%(30/44)and 54.6%(24/44)respectively,and the specificity were all 100%(12/12).Conclusion Based on the serum and cervical secretion specific HPV 6b E7 antibodies from patients with CA to diagnose HPV 6b infection,results showed medium sensitivity and high specificity,and could further be used to investigate the epidemiological characteristics of HPV 6b infection.

Immunogenicity of multi-epitopes gene of major outer membrane protein of Chlamydia trachomatis / 中华预防医学杂志

<p><b>OBJECTIVE</b>To construct a recombinant eukaryotic expression plasmid pcDNA3.1-Ct MOMP168 including Ct MOMP multi-epitopes gene, and evaluate the Ct MOMP-specific humoral and cellular immune response induced by pcDNA3.1-Ct MOMP168 in BALB/c mice.</p><p><b>METHODS</b>Recombinant plasmid pcDNA3.1-Ct MOMP168 including Ct MOMP multi-epitopes gene was constructed. Then, BALB/c mice were randomly assigned to receive (intramuscular injection) either pcDNA3.1-Ct MOMP168 or pcDNA3.1 or PBS (n = 12, 100 microg/time per mouse), and the same immunization schedule was repeated for the third time at 2 week intervals. The titers of anti-Ct MOMP antibody and its antibody subtypes in sera, the cytotoxicity of Ct MOMP-specific cytotoxic T lymphocyte (CTL) in spleen, and the level of cytokine (IFN-gamma, IL-4, IL-10)-producing CD3(+) T cells in spleen were detected by ELISA, LDH release assays and intracellular cytokine staining-fluorescence activated cell sorter (ICS-FACS), respectively.</p><p><b>RESULTS</b>The recombinant plasmid pcDNA3.1-Ct MOMP168 was able to induce Ct-specific antibody response (A(490) = 0.973 +/- 0.136; serum titer was 1:1000) as compared with pcDNA3.1 (A(490) = 0.180 +/- 0.025) and PBS (A(490) = 0.110 +/- 0.015), and the major antibody subtype was IgG2a with statistical significance (F = 106.884, P < 0.05). When the ratio of effector cells and target cells reached to 50:1, the activity of cytotoxic T-lymphocyte in pcDNA3.1-Ct MOMP168 immunized mice (41.71% +/- 8.34%) was significantly higher (F = 22.315, P < 0.05) than that in pcDNA3.1 immunized mice (18.40% +/- 3.45%) and PBS immunized mice (14.50% +/- 2.42%). The levels of CD3(+) IFN-gamma(+) T cells in pcDNA3.1-Ct MOMP168 immunized mice (1.15% +/- 0.16%) were significantly higher (F = 99.638, P < 0.05) than that in pcDNA3.1 immunized mice (0.12% +/- 0.08%) and PBS immunized mice (0.09% +/- 0.03%), while the significant difference in the levels of IL-4(+) CD3(+) T cells and IL-10(+) CD3(+) T cells was not observed (F = 0.886 and 1.112, P > 0.05) between pcDNA3.1-Ct MOMP168 immunized mice (0.13% +/- 0.08% and 0.14% +/- 0.08%) and pcDNA3.1 (0.07% +/- 0.05% and 0.13% +/- 0.06%) or PBS immunized mice (0.08% +/- 0.04% and 0.07% +/- 0.04%).</p><p><b>CONCLUSION</b>In BALB/c mice, the recombinant plasmid pcDNA3.1-Ct MOMP168 might induce not only the generation of Ct-specific antibody, but also the high level of Ct MOMP-specific CD3(+) IFN-gamma(+) T cells.</p>

Cut-off period of subclassification and pathological features of severe hepatitis based on clinical and pathological analyses / 中华实验和临床病毒学杂志

<p><b>BACKGROUND</b>To explore the cut-off period of subclassification and pathological features of severe hepatitis (SH).</p><p><b>METHODS</b>Based on combined clinical and pathological analyses, the complete clinical and biopsy or autopsy liver tissues data from 196 cases of patients with severe hepatitis were investigated. Meanwhile, proliferative hepatocytes, cholangioepithelia and collagens were identified by a panel of monoclonal antibodies such as those against albumin, cytokeratin 18,19 and collagen I, III with immunohistochemical method.</p><p><b>RESULTS</b>The clinical and pathological analyses indicated the cut-off periods of acute, subacute and chronic SH (ASH,SSH and CSH) were (13.4+/-7.2) d, (77.4+/-69.3) d and (80.5+/-63.2) d, respectively. Among all SH cases, one case of ASH patient presented clinical manifestation and pathological changes of ASH for 21 days, however, one patient with SSH was demonstrated 12 day course by histological examination. The time of cut-off period between ASH and SSH in child cases was shorter than that in adult cases. Histologically, ASH liver tissues showed massive and/or submassive necrosis caused by one attack, with congestive sinusoid frameworks and proliferative cholangioepithelium-like hepatocytes, while SSH liver tissues presented combined fresh and old submassive or massive necrosis caused by multiple attacks, accompanied by obviously proliferative bile ducts and sinusoid framework collapse.However, the pathological changes of CSH showed ASH- or SSH-like lesions on the background of chronic liver injury.</p><p><b>CONCLUSION</b>Our data indicated that the cut-off period between ASH and SSH is in accordance with the Scheme of Viral Hepatitis Prevention and Therapy, China, published in 2000, but excluded a part of child SH cases. In our study, the authors found a few pathological features in ASH and SSH.</p>

Clinical pathology and pathogenesis of severe acute respiratory syndrome / 中华实验和临床病毒学杂志

<p><b>BACKGROUND</b>To explore the pathological features and pathogenesis of severe acute respiratory syndrome (SARS) to provide evidence for the clinical treatment and prevention of SARS.</p><p><b>METHODS</b>Pathological features of 2 cases of full autopsy and 4 cases of needle biopsy tissue samples from the patients who died from SARS were studied by light and electron microscopy. The distribution and quantity of lymphocyte subpopulations in the lungs and immune organs from SARS patients were analyzed by immunohistochemistry. The location and semi-quantitative analysis of SARS coronavirus in the tissue specimens were studied by electron microscopy, in situ hybridization and immunohistochemistry.</p><p><b>RESULTS</b>In total of 6 cases, diffuse alveolar damage and alveolar cell proliferation were common. The major pathological changes of 2 autopsy cases of SARS in lung tissues were acute pulmonary interstitial and alveolar exudative inflammation, and 2 autopsy and one biopsy lung tissues showed alveolar hyaline membrane formation. Terminal bronchiolar and alveolar desquamation of lung tissues in one autopsy and 2 biopsy cases were noted. Among 6 cases, 2 biopsy cases presented early pulmonary fibrosis and alveolar organization. Meanwhile, the immune organs, including lymph nodes and spleens from 2 autopsy cases of SARS whose disease courses were less than 12 days showed extensive hemorrhagic necrosis, reactive macrophage/histocyte proliferation, with relative depression of mononuclear and granulocytic clones in the bone marrows. However, spleen and bone marrow biopsy tissue samples from 4 dead SARS cases whose clinical course lasted from 21 to 40 days presented repairing changes. SARS coronaviruses were mainly identified in type I and II alveolar epithelia, macrophages, and endothelia; meanwhile, some renal tubular epithelial cells, cardiomyocytes, mucosal and crypt epithelial cells of gastrointestinal tracts, parenchymal cells in adrenal glands, lymphocytes, testicular epithelial cells and Leydig's cells were also detected by electron microscopy combined with in situ hybridization. The semi-quantitative analysis of lymphocyte subpopulations revealed that the proportion of CD8+ T lymphocytes were about 80% of the total infiltrative inflammatory cells in the pulmonary interstitium, with a few CD4+ lymphocytes CD3+, CD4+, CD8+ or CD20+ lymphocyte subpopulations were obviously decreased and there was imbalance in number and proportion, while CD57+, CD68+, S-100+ and HLA-DR+ cells were relatively increased in lymph nodes and spleens.</p><p><b>CONCLUSIONS</b>Histologically, the pulmonary changes could be divided into acute inflammatory exudative, terminal bronchiolar and alveolar desquamative and proliferative repair stages or types during the pathological process of SARS. SARS coronavirus was found in multi-target cells in vivo, which means that SARS coronavirus might cause multi-organ damages which were predominant in lungs. There were varying degrees of decrease and imbalance in number and proportion of lymphocyte subpopulations in the immune organs of the patients with SARS. However, these changes may be reversible. It was found that cellular immune responses were predominant in the lungs of SARS cases, which might play an important role in getting rid of coronaviruses in infected cells and inducing immune mediated injury.</p>