La batalla decisiva contra la fiebre tifoidea en Santiago de Chile en el siglo XX

Hasta 1983, cuando alcanzaba la increíble tasa de 118 casos por 100.000 habitantes, la fiebre tifoidea era la peor amenaza infecciosa en Santiago, Chile, ciudad que figuraba junto a Ciudad de México, El Cairo y Bombay, como una de las con mayor endemia en el mundo. El Ministerio de Salud respondió formando el Comité de Tifoidea de Chile, con participación de expertos nacionales y del grupo de Myron Levine, de la Universidad de Maryland, que llevó a cabo ingeniosas investigaciones, culpando al río Mapocho, cuyas aguas contaminadas con Salmonella typhi regaban los predios agrícolas vecinos, conformando así un ciclo largo de infección. Las vacunas antitíficas ensayadas (oral Ty21a atenuada y polisacárido capsular Vi inyectable) no mostraron eficacia, los portadores crónicos no se trataron, pero una campaña sanitaria a través de la televisión contribuyó decisivamente a mejorar los hábitos higiénicos de la población, fortalecida por el pánico que causó la llegada del cólera en 1991, y la fiebre tifoidea prácticamente desapareció del escenario.

Until 1983, when reached the incredible frequency of 118 cases for 100.000 habitants, typhoid fever was the worst infectious threat in Santiago, Chile, city that appeared next to Mexico City, Cairo and Bombay, as one of the most endemic in the world. The Ministry of Health responded with the creation of The Chilean Typhoid Committee, with the participation of national experts and Myron Levine's group, which carried out ingenious investigations blaming the Mapocho River, whose waters contaminated with Salmonella typhi irrigated the neighboring farms, thus conforming a long cycle of infection. Typhoid vaccines tested (strain Ty 21a oral and Vi capsular polysaccharide) did not show efficacy, chronic carriers were not treated, but a health campaign on television made a decisive contribution to improving hygiene habits of the population, strengthened by the panic caused by the arrival of cholera in 1991, and typhoid fever practically disappeared from the stage.

Clinical analysis of 42 elderly patients with pulmonary cryptococcosis / 中华老年医学杂志

Objective:To analyze the clinical features, imaging characteristics, diagnosis and treatment of elderly patients with pulmonary cryptococcosis, and to propose considerations for the early diagnosis and treatment of pulmonary cryptococcosis.Methods:Clinical data of 42 elderly patients with pulmonary cryptococcosis diagnosed at the First Affiliated Hospital of Zhejiang University School of Medicine from January 2015 to September 2020 were retrospectively analyzed.Differences in clinical data were compared between immunocompromised patients and immunocompetent patients by using the SPSS software.Results:The mean age of patients of with pulmonary cryptococcosis was(66.0±5.3)years.Of the cases, 27 were immunocompromised, with common underlying diseases such as autoimmune rheumatic disorders, tumors and chronic kidney disease.Main clinical manifestations were cough, sputum expectoration, fever and chest tightness.Twenty-two cases showed nodules on chest CT scans, most of which contained multiple nodules.Twenty-four cases showed unilateral lesions, mainly in the lower lobe.There was no significant difference in clinical manifestations, lesion types or location distribution between the immunocompromised and immunocompetent groups( P>0.05), while the incidence of air bronchograms was higher in the immunocompetent group than in the immunocompromised group( P<0.05). Seventeen cases were diagnosed by histopathology, and the clinical diagnosis of 25 cases was confirmed by the positive detection of capsular polysaccharide antigens.Nine cases were treated surgically, 1 case underwent clinical observation postoperatively, and 8 cases were treated with fluconazole after surgery.Thirty-three cases were treated with antifungal therapy, 6 of whom were treated with a combination of drugs.Eight cases were lost to follow-up, 29 were cured or improved, 2 progressed, and 3 died. Conclusions:Pulmonary cryptococcosis in the elderly is more common in immunocompromised patients, with atypical clinical symptoms and a high rate of misdiagnosis.Cryptococcal capsular polysaccharide antigen testing is helpful for early diagnosis, and treatment plans need to be chosen and adjusted according to the patient's immune status and specific conditions.

Frequency of Staphylococcus aureus virulence genes in milk of cows and goats with mastitis / Frequência de genes fatores de virulência de Staphylococcus aureus em leite de vacas e cabras com mastite

The present study determined the frequency of Staphylococcus aureus virulence genes in 2,253 milk samples of cows (n=1000) and goats (n=1253) raised in three different geographical regions of the state Pernambuco, Brazil. The presence of genes of virulence factors associated to adhesion to host cells (fnbA, fnbB, clfA and clfB), toxinosis (sea, seb, sec, sed, seg, seh, sei, tsst, hla and hlb), and capsular polysaccharide (cap5 and cap8) was evaluated by PCR. A total of 123 and 27 S. aureus strains were isolated from cows' and goats' milk, respectively. The sec and tsst genes were detected exclusively in goats' isolates, while the seh gene was only identified in cows' isolates. The number of toxin genes per strain showed that goats' isolates are likely more toxic than bovines' isolates. The cap5 genotype predominated in both host species, especially in strains collected from cows raised in the Agreste region. The cap8 genotype is likely more virulent due to the number of virulence genes per strain. The results of the present study demonstrate that S. aureus may pose a potential threat to human health in Brazil, and, therefore, these results should support actions related to mastitis control programs.(AU)

O presente estudo determinou a frequência de genes de virulência de Staphylococcus aureus em 2253 amostras de leite, sendo de vacas n=1000 e de cabras n=1253, procedentes das três regiões geográficas do estado de Pernambuco, Brasil. A presença de genes de fatores de virulência associados à adesão às células hospedeiras (fnbA, fnbB, clfA e clfB), toxinosis (sea, seb, sec, sed, seg, seh, sei, tsst, hla e hlb) e polissacarídeo capsular (cap5 e cap8) foram avaliadas por PCR. Um total de 123 e 27 cepas de S. aureus foram isoladas do leite de vacas e cabras, respectivamente. Os genes sec e tsst foram detectados exclusivamente em isolados de cabras, enquanto o gene seh foi identificado apenas em isolados de vaca. O número de genes de toxina por cepa mostrou que os isolados de cabras são potencialmente mais tóxicos do que os isolados obtidos de bovinos. O genótipo cap5 predominou em ambas as espécies hospedeiras, especialmente em cepas coletadas de vacas criadas na região Agreste. O genótipo cap8 é potencialmente mais virulento devido ao número de genes de virulência por isolado. Os resultados do presente estudo demonstram que S. aureus pode representar uma ameaça potencial para a saúde humana no Brasil e, portanto, estes resultados devem subsidiar ações relacionadas aos programas de controle de mastite.(AU)

Comparative genomics reveals diverse capsular polysaccharide synthesis gene clusters in emerging Raoultella planticola

Raoultella planticola is an emerging zoonotic pathogen that is associated with rare but life-threatening cases of bacteremia, biliary tract infections, and urinary tract infections. Moreover, increasing antimicrobial resistance in the organism poses a potential threat to public health. In spite of its importance as a human pathogen, the genome of R. planticola remains largely unexplored and little is known about its virulence factors. Although lipopolysaccharides has been detected in R. planticola and implicated in the virulence in earlier studies, the genetic background is unknown. Here, we report the complete genome and comparative analysis of the multidrug-resistant clinical isolate R. planticola GODA. The complete genome sequence of R. planticola GODA was sequenced using single-molecule real-time DNA sequencing. Comparative genomic analysis reveals distinct capsular polysaccharide synthesis gene clusters in R. planticola GODA. In addition, we found bla TEM-57 and multiple transporters related to multidrug resistance. The availability of genomic data in open databases of this emerging zoonotic pathogen, in tandem with our comparative study, provides better understanding of R. planticola and the basis for future work.

Mycoplasma pneumoniae capsular polysaccharides inhibit phagocytosis and membrane molecules expression of dendritic cells / 中国免疫学杂志

Objective:To study the influences of Mycoplasma penumoniae capsular polysaccharide (CPS) on the phagocytosis and membrane molecules expression of the human peripheral blood mononuclear cells derived dendritic cells by binding to dendritic cell-specific intercellular adhesion molecule-3-grabbing nonintegrin (DC-SIGN),so as to know the effect of CPS on the maturation of dendritic cells.Methods:M.pneumoniae strain was cultivated and CPS was extracted.Human peripheral blood mononuclear cells were separated and induced to dendritic cells,then identified the cells by flow cytometry and observation under the microscope.CPS was used to treat dendritic cells or cells pretreated with DC-SIGN monoclonal antibody,and then FITC-dextran phagocytosis and surface markers CD83,HLA-DR,CD80 and CD86 were detected by flow cytometry.Results:The dendritic cells tended to form colony groups.The positive rate of CD11c molecule in the cultured dendritic cells was about 86.27％.After stimulated by CPS,the FITC-dextran fluorescence mean intake by dendritic cells were increased (P＜0.05),while the cell surface membrane molecules CD83,HLA-DR,CD80 and CD86 were decreased significantly when compared with the PBS treated control cells(P＜0.05).When blocked DC-SIGN with the monoclonal antibody,the FITC-dextran fluorescence mean and membrane molecules expression had no statistical difference with the control cells(P＞0.05).Conclusion:M.pneumoniae CPS can promote the phagocytic function of DC and inhibit the expression of CD83,HLA-DR,CD80 and CD86.

The significance and therapy monitoring of detection cryptococcal capsular polysaccharide antigen in HIV-positive patients with secondary cryptococcal meningitis / 国际检验医学杂志

Objective To discuss the significance and therapy monitoring of detection cryptococcal capsular polysaccharide anti-gen in HIV-positive patients with secondary cryptococcal meningitis.Methods Cerebrospinal fluid and serum samples of 23 HIV-positive patients with secondary cryptococcal meningitis were collected,retrospective analysis was conducted in the capsular antigen titer changes data which from 23 patients with the cerebrospinal fluid(CSF)and serum samples before and after treatment.And the capsular antigen in 1 3 patients before and after treatment of CSF and serum specimens were compared in matching t test.Results The CSF and serum samples before and after treatment of cryptococcal capsular antigen titer decreased both with statistical signifi-cance(P<0.01),but by effective treatment and fungal culture and smears were negative in the 13 patients,the cryptococcal capsu-lar antigen was still positive.Conclusion Cryptococcal capsular antigen test could help improve HIV-infected patients with crypto-coccal meningitis secondary to early diagnosis,it could be used to determine the efficacy of antigen titer,but not as a cure indicator.

Preparation of Streptococcus pneumonia type 3 capsular polysaccharide conjugate vaccine / 中国免疫学杂志

Objective:To prepare Streptococcus pneumonia type 3 capsular polysaccharide conjugate vaccine.Methods:Strep-tococcus pneumonia type 3 capsular polysaccharide was covalently linked to protein CRM197 and its immunogenicity was evaluated in infant mice.Results:Through the preliminary research, we found that the polysaccharide was treated with 0.2 mol/L acetic acid at 85℃ for 1 h,activation grade reached to 10.0,and the radio of polysaccharide and protein was 20∶10,could induce infant mice to produce the high titers of antibodies.Conclusion:This result shows that conjugate vaccine prepared under this condition retained intact antigenicity.It is applicable to prepare Streptococcus pneumonia type 3 capsular polysaccharide conjugate vaccine by the process condi-tions.

Cyclic AMP and Cyclic AMP-Receptor Protein are Required for Optimal Capsular Polysaccharide Expression

Vibrio vulnificus causes fatal infections in susceptible individuals. Group 1 capsular polysaccharide (CPS) operon is responsible for CPS expression, which plays an essential role in the pathogenesis of this pathogen. Cyclic AMP (cAMP) and cAMP receptor protein (crp) complex, which responds to glucose availability and functions as a global regulator, has been known to affect CPS production in this pathogen. This study was undertaken to experimentally verify whether cAMP-Crp directly or indirectly affects CPS production. A mutation in cyaA encoding adenylate cyclase, which is required for cAMP biosynthesis, inhibited V. vulnificus growth and changed opaque colonies to translucent colonies, and these changes were recovered by complementing cyaA or by adding exogenous cAMP. A mutation in crp encoding Crp also inhibited V. vulnificus growth and changed opaque colonies to translucent colonies, and these changes were recovered by complementing crp. Moreover, the crp or cyaA mutation decreased the susceptibility of V. vulnificus against NaOCl. The crp mutation reduced the transcription levels of group 1 CPS operon on a per cell basis. Glucose addition in the absence of Crp stimulated V. vulnificus growth, changed translucent colonies to opaque colonies, and increased the transcription levels of group 1 CPS operon. These results indicate that cAMP or Crp is indirectly involved in optimal CPS production by positively affecting metabolism or V. vulnificus growth rather than by directly controlling the expression of group 1 CPS operon.

Study on the molecular size distribution and the structural characteristics of group B meningococcal cap-sular polysaccharides / 中华微生物学和免疫学杂志

Objective To investigate the molecular size distribution and the structure of group B me-ningococcal capsular polysaccharides for the development of vaccines .Methods The molecular size distribution of group B meningococcal capsular polysaccharides was analyzed by chromatography on a Sepharose CL -4B col-umn.The molecular weight of repeat units were measured by matrix assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF-MS).The structural characteristics of group B meningococcal capsular polysaccharides were analyzed by nuclear magnetic resonance ( NMR) based on the chemical shift of all charac-teristic protons by using group C meningococcal capsular polysaccharides and sialic acid as the controls .Results The KD value of group B meningococcal capsular polysaccharides extracted from 15 strains were ranged from 0.60 to 0.76.The molecular weight of repeat units was 284, which was identical to the theoretical value .The group B meningococcal capsular polysaccharides were 2→8 linked homopolymers of sialic acid lacking O-acetyl groups.Conclusion The group B meningococcal capsular polysaccharides had lower molecular weights , which might result in their poor immunogenicity .The structure of group B meningococcal capsular polysaccharides could be quickly and accurately analyzed by NMR technology .

A comparative study of a double immune-diffusion assay and a rate nephelometer analysis for evalua-ting the antigen activity of pneumococcal capsular polysaccharides / 中华微生物学和免疫学杂志

Objective To comparatively analyze the advantages and disadvantages between a double immune-diffusion assay and a rate nephelometer analysis for the detection of antigen activity of pneu -mococcal capsular polysaccharides .Methods The antigen activity of pneumococcal capsular polysaccharides of serotypes 1,6B,9V,10A,14 and 19A from four manufacturers and ATCC were analyzed by a double im-mune-diffusion assay and a rate nephelometer analysis , respectively .The effects of antiserum samples and gain values on the rate response value were evaluated .Results The sample 4 of type 9V showed no antigeni-city with a rate response value similar to that of negative control as indicated by both tests .However ,the pre-cipitation lines and the rate response values presented by other polysaccharide samples differed in a wide range.Results of the rate nephelometer analysis were not affected by the anti -serum samples from different sources and the gain values .Conclusion The rate nephelometer analysis could quantitatively analyze the antigen activity of pneumococcal capsular polysaccharides .

Desenvolvimento de meio quimicamente definido para produção de polissacarídeo capsular em cultivo de Streptococcus pneumoniae sorotipo 14 / Development of a chemically defined medium for capsular polysaccharide production by Streptococcus pneumoniae serotype 14

Neste trabalho avaliou-se a influência de fontes de carbono (FC) e composições de meio definido no crescimento celular e na produção do polissacarídeo PS14. Em batelada, testou-se como FC glicose, sacarose e frutose em diferentes concentrações. Testou-se também meios com ausência dos aminoácidos asparagina, ácido aspártico, fenilalanina, serina, alanina, treonina, triptofano, lisina e tirosina, das vitaminas/cofatores ácido fólico, piridoxamina, ácido p-aminobenzóico, b-NAD e riboflavina, além bem como da adição de maiores concentrações de aminoácidos identificados como importantes. Em cultivo contínuo foram avaliadas vazões específicas de alimentação (D) de 0,1h-1a 0,5h-1 e a influência das bases nitrogenadas. O meio com sacarose como FC, retirada dos aminoácidos e vitaminas citados e adição do dobro de glicina isoleucina, leucina, valina e o triplo de glutamina levou à maior produção de PS14 (441mg/L). Obteve-se a maior produtividade com D=0,4h-1e a maior quantidade de PS14 com adenina na concentração original no meio de cultura.

In this work we assessed the influence of different carbon sources (CS) and defined medium compositions on cell growth and polysaccharide PS14 production. In bath, glucose, sucrose and fructose were tested at different concentrations. Also, media were tested with absence of the amino acids: asparagine, aspartic acid, phenylalanine, serine, alanine, threonine, tryptophan, lysine, and tyrosine, and vitamins/cofactors: folic acid, pyridoxamine, p-aminobenzoic acid, riboflavin and b-NAD, besides the addition of higher concentration of amino acids identified as important. In continuous cultivation, dilution rates (D) from 0.1 h-1 to 0.5 h-1 were evaluated as well as the influence of nitrogenous bases. The medium containing sucrose as CS, absence of amino acids and vitamins and addition of twice glycine isoleucine, leucine, valine, and triple glutamine led to higher production of PS14 (441mg/L). D of 0.4 h-1 showed higher productivity and adenine in standard concentration produced greater amounts of PS14.

Establishment of a quantitative ELISA assay recommended by WHO for the detection of human IgG antibodies specific for Streptococcus pneumoniae capsular polysaccharides (Pn PS ELISA) / 中华微生物学和免疫学杂志

Objective To establish a standardized quantitative enzyme-linked immunosorbent as-say ( ELISA) recommended by WHO for the detection of human IgG antibodies specific for Streptococcus pneumoniae capsular polysaccharides ( Pn PS ELISA ) .Methods According to the WHO recommended standard Pn PS ELISA protocol , capsular polysaccharide concentrations of 13 serotypes (1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F, 23F) of Streptococcus pneumonia for coating were optimized;the ELISA plates and AP conjugated goat anti-human IgG antibody for the detection were experimentally selected .Using the established assay parameters assured by testing quality control standards ( QCs) provided by WHO refer-ence laboratory , a panel of 16 LIBP ( Lanzhou Institute of Biological Products Co .Ltd.) QCs were measured for comparison analysis between WHO reference laboratory and LIBP laboratory .In the meantime , the range of IgG concentrations of an internal QC panel 907 for 13 serotypes of pneumococcal capsular polysaccharide were established for routine QC work in LIBP laboratory , and inter-assay precision within LIBP laboratory was assessed as well .Results The standardized Pn PS ELISA assay established in LIBP laboratory met the criteria required by WHO .There was a high correlation between the data collected by WHO reference labora -tory and LIBP laboratory (slope=0.94, coefficient of correlation r=0.97, P<0.05).Eighty one percent of IgG concentrations measured by LIBP laboratory were within the range of ±40%of those measured by WHO reference laboratory , which met the criteria of 75%data falling within the ambit of ±40%of assigned values commonly used for comparison .The ranges of IgG concentration in LIBP QC 907 for 13 serotypes had been established.The inter-assay precision in LIBP laboratory was high with coefficiency of variation ( CV) less than 30%.Conclusion LIBP laboratory has successfully established the standardized ELISA recommended by WHO for quantitative detection of human IgG antibodies against pneumococcal capsular polysaccharides (Pn PS ELISA).The range of IgG concentrations in LIBP QC 907 for 13 serotypes of pneumococcal capsular polysaccharide are also established for routine quality-control practice .

The difference of anti-pneumococcal capsular polysaccharide IgG levels in plasma of asthmatic and non-asthmatic children / 临床儿科杂志

Objectives To explore the humoral immunologic mechanisms of the susceptibility to invasive pneumococcal diseases (IPD) in asthmatic children. Methods Plasma samples were collected from 43 asthmatic and 20 non-asthmatic chil-dren. Anit-pneumococcal capsular polysaccharide (PPS)-IgG concentrations were measured by enzyme-linked immunosorbent assays. Results The mean concentrations of anti-PPS 14, 19A and 23F-IgG were signiifcantly higher in asthmatic children than in non-asthmatic children (P<0.05). The ratios of the asthmatic children who had anti-PPS 14, 19A and 23F-IgG concentrations higher than the protective antibody level (≥0.2 μg/ml ) were 100%for all the serotypes. Conclusions The immune responses of producing anti-PPS IgG to defense IPD were normal in asthmatic children. Asthmatic children may be more susceptive to pneumococcal infection or colonization than non-asthmatic children.

Structure and molar mass analysis of pneumococcal capsular polysaccharides by 1 H NMR and HPSEC-MALLS / 中华微生物学和免疫学杂志

Objective To analyze the structures and molecular weight distributions of the capsular polysaccharides from 6 serotypes of pneumococcus .Methods The structures of pneumococcal capsular pol-ysaccharides of 6 serotypes were analyzed by 1 H nuclear magnetic resonance ( NMR) .Chemical shifts of all characteristic protons were investigated to analyze polysaccharide integrity and inter -assay consistency .High performance size exclusion chromatography-multi angle laser light scattering ( HPSEC-MALLS) was used to measure the molecular weights .Results The chemical shifts of all characteristic protons of the pneumococ-cal capsular polysaccharides of 6 serotypes were consistent with the standard chemical shift .The weight-aver-age molecular mass of the pneumococcal capsular polysaccharides ranged from 7.182×104 g/mol(for serotype 19A) to 1.273×106 g/mol(for serotype 9V)examined by HPSEC-MALLS.Conclusion The structures and molecular weight distributions of pneumococcal capsular polysaccharides could be rapidly and effectively ana -lyzed by 1 H NMR and HPSEC-MALLS.Moreover, C-PS and acetate contained in capsular polysaccharides could also be detected .HPSEC-MALLS is an applicable method for the quantitative analysis of molar mass distributions in different serotypes of pneumococcal capsular polysaccharides . Although 1 H NMR and HPSEC-MALLS have been accepted as the quality control measurements by WHO , to use them as the re-placements of the traditional QC method still needs further investigation .

Research on PCR determining of type b Haemophilus influenzae strains and immunogenicity of polysaccharide conjugates / 中华微生物学和免疫学杂志

Objective To determine Haemophilus influenzae type b strains in molecular level using PCR,and to study the immunogenicity of capsular polysaccharide conjugates in mice.Methods Extracting genomes using bacterial DNA extract kit from Hoemophilus influenzae type b strains,and PCR for determining the strains through serotyping-specific and capsular genotyping primers respectively.Various capsular polysaccharides conjugated TT respectively,and the conjugates were administered subcutaneously to mice through dilution.After vaccination with two doses,blood samples were collected for the detection of antibody levels to polyribosylribitol phosphate ( PRP),the capsular polysaccharide of Hib.Results All five Haemophilus influenzae type b strains contain type-specific(482 bp) and capsular type (343 bp)DNA fragment through PCR detecting.The DNA fragments were sequenced.BLAST show that these sequences are 100％ homology comparing the above strains respectively,and are 99％ and 100％ homology comparing the GenBank X78559.1 and M19995.1 respectively.The immunogenicity of mice from various capsular polysaccharide conjugates (PRP-TT) was not significantly different by ELISA detecting.Conclusion Through PCR,Haemophilus influenzae type b strain can be determined in molecular level.The immunogenicity of mice from purified capsular polysaccharide conjugates was not different.The study provides a detection means for the features and heredity stability of Haemophilus influenzae type b strain and reference data for the immunogenicity of different polysaccharide conjugates in vaccine research and development and production.

Immunogenicity and hereditary stability of Neisseria meningitidis serogroup W135/Y strains used in conjugate vaccine production / 中华微生物学和免疫学杂志

Objective To evaluate the immunogenic stability and hereditary stability of Neisseria meningitides serogroup W135/Y[CMCC(B)29037/CMCC(B)29028]within all the passages,which isolated from china.Methods The toxicity of the 3rd,5th,10th,15th,20th,25th and 30th passage of the Neisseria meningitidis was assayed in mice.Serological detection and biochemical detection were measured,and immunized mice subcutaneously.The antigeeicity of each passage of Neisseria meningitides serogroup W135/Y were measured by serum bactericidal test and the indirect ELISA.With the 30 passage of Neisseria meningitides serogroup W135/Y,the effect to the encephalic tissue was measured in mice.Fermented the Neisseria meningitides serogroup W135/Y with 30 passage and purified the capsular polysaccharide,then analyzed the quality respectively.Results The LD50 of the strains CMCC(B)29037/29028 of each passage was low(LD50 ≥ 109),and all the 30logical detection and all the 30 passage of the two strains were half in the tube agglutination.Glucose and maltose fermentation test were positive.Fructose,sucrose and lactose fermentation test were negative.The GMT of immunogenicity were 1114 and 2229 respectively and all the 30 passage were more than 640 and 1040 respectively.After Immunization with individual 30 passage of the Neisseria meningitides,the titer in serum bactericidal assay(SBA)and indirect ELISA were no difference.The capsular polysaccharide purified from Neisseria meningitides serogroup W135/Y met the quality standard.Conclusion Neisseria meningitides serogroup W135/Y,CMCC(B)29037/29028,used in the manufacture of the meningococcal conjugate vaccine,are stable in the toxicity,antigenicity,immunogenicity.Serological detection and biochemical detection are qulified,and the capsular polysaccharide has met the quality standard.

Study on the immunogenicity and the stability of the toxicity,antigenicity of Neisseria meningitidis serogroup A/C / 中华微生物学和免疫学杂志

Objective To study the stability of the toxicity,antigenicity and immunogenicity of Neisseria meningitidis serogroup A/C[CMCC(B)29201/29205],and to analyze the quality of the capsular polysaecharide extracted from Neisseria meningitidis.Methods The toxicity of the 3rd,5th,10th,15th,20th,25th and 30th passage of the Neisseria meningitidis was assayed in mice,and the antigenicity of each passage was measured by the tube agglutination test(TAT)and ELISA.The effect of individual 30 passages of Neisseria nveningitidis on the brain tissue and the immunogenicity of each passage were tested in mice,and the capsular polysaccharide was purified and analyzed.Resuits The LD50 of the strains CMCC(B)29201/29205 of each passage was low(≥109/ml),and all the 30 passages of the two strains had no effect on the brain tissue of the mice.The titer of each passage was 1∶320 in TAT and more than 1∶3752 in ELISA.After immunization with individual 30 passages of the Neisseria meningitidis the titers in serum bactericidal assay (SBA)were all more than 1∶32.The capsular polysaccharide purified from Neisseria meningitidis met the quality standard of the requirement.Conclusion The strains of Neisseria meningitidis serogroup A/C used in the manufacture of the meningococcal conjugate vaccine,are stable in the toxicity,antigenicity and immunogenicity.And the capsular polysaccharide has met the quality standard.

Capsular polysaccharide typing of domestic mastitis-causing Staphylococcus aureus strains and its potential exploration of bovine mastitis vaccine developmen. I. capsular polysaccharide typing, isolation and purification of the strains

One hundred seven isolates of Staphylococcus aureus from bovine mastitis were investigated for colony morphology in serum-soft agar (SSA), autoagglutination in salt, and capsular serotype. Capsular polysaccharide (CP) was purified and quantified from the extracts of clinical isolates. Overall, 89 isolates (83.2%) were diffuse in the SSA, without any difference in the proportion of diffuse colony between type 5 and type 8 strains. Some strains exhibited compact colonies in the SSA and expressed CP as determined by an enzyme-linked immunosorbent assay, indicating that compact morphology does not exclude encapsulation. The majority of the strains (11/12) showed autoagglutination in the salt aggregation test. The serotype 336 accounted for 46.7% of the isolates followed by serotype 5 (12.1%) and serotype 8 (12.1%). Particularly, twenty-six (24.3%) isolates reacted with two serotypes; 7 for type 8/336 and 19 for type 5/336. Five isolates (4.7%) were nontypeable with monoclonal antibodies specific for CP serotype 5, 8, or 336. The CP concentration in culture supernatants varied with the serotypes, and the total amount of CP produced by cells grown in a liquid medium was much less than that produced by cells grown on a solid medium. The Western blotting indicated that the CP bands of S. aureus serotype 5 and 8 were ranged in the molecular mass of 58-84 kilodalton (kDa), with additional bands in the region of approximately >or= 48 or