Optimization of condition for prokaryotic expression of recombinant tetanus toxin heavy chain fragment C protein / 中国生物制品学杂志

@#Objective To optimize the condition for prokaryotic expression of recombinant tetanus toxin heavy chain fragment C(rTTHc) protein.Methods The rTTHc gene fragment after optimization of codon was inserted into prokaryotic expression vector pET30a,low temperature expression vector pCold Ⅱ and high temperature expression vector pBV220separately.The constructed recombinant plasmids were transformed to E.coli BL21(DE3).The expression levels and solubility of recombinant protein at various temperatures were compared.Results The expression level of pBV220-rTTHc after induction at 42 ℃ for 4 h was relatively low,and the protein solubility was poor.The expression level of pET30a-rTTHc after induction at 37 ℃ for 4 h was equivalent to that of pCold-rTTHc after induction at 15 ℃ for 8 h,while the solubility of the former was slightly lower than that of the latter.However,both the expression level and solubility of pET30a-rTTHc after induction at 28 ℃ for 4 h were high,while the expression time was short.Conclusion The pET30a-rTTHc induced by2 mg/mL IPTG at 28℃ is optimal for high expression of rTTHc protein.

Tétanos generalizado: Una amenaza persistente, reporte de tres casos y revisión de la literatura / Generalized tetanus: A persistent threat, review of the literature and report of three cases

RESUMEN INTRODUCCIÓN: El tétanos es una enfermedad inmunoprevenible, ocasionada por la bacteria Clostridium tetani, desencadenando una enfermedad caracterizada por espasmos musculares, insuficiencia respiratoria y disautonomías, potencialmente mortal. MATERIALES Y MÉTODOS: Presentamos una serie de tres pacientes que consultaron al servicio de urgencias por presentar trismus, rigidez muscular generalizada y dificultad respiratoria, requiriendo manejo en la unidad de cuidados intensivos, con relajación muscular y administración intramuscular e intratecal de inmunoglobulina antitetánica, con evolución satisfactoria en todos los casos. DISCUSIÓN: Su tratamiento está divido en dos grandes secciones; la primera parte, el control de la infección y eliminación del agente causal, con lavado y desbridamiento de heridas, administración de antibióticos y neutralización de la neurotoxina. La segunda parte del tratamiento está en el soporte vital en la unidad de cuidados intensivos, con la administración de sedación, relajación muscular, control de disautonomías y manejo de complicaciones. CONCLUSIONES: El tétanos a pesar de los avances en vacunación aún es una enfermedad presente, cuyo diagnóstico y tratamiento rápido y adecuado, permite sobrevivir a los pacientes, como en los casos aquí reportados.

ABSTRACT INTRODUCTION: Tetanus is an immuno-preventable disease, produced by the bacterium Clostridium tetani, that causes a disease characterized by muscle spasms, respiratory insufficiency and life-threatening dysautonomia. MATERIALS AND METHODS: We present a series of three patients who consulted for trismus, muscle stiffness and respiratory failure, which required intensive care management, muscle relaxation, intramuscular and intrathecal administration of tetanus immu-noglobulin, with satisfactory outcomes in all the cases. DISCUSSION: Its treatment is divided into two main sections; the first part, the control of infection and elimination of the causative agent, with washing and debridement of wounds, administration of antibiotics and neutralization of the neurotoxin. The second part is life support in the intensive care unit, with the administration of sedation, muscular relaxation and control of dysautonomia and the management of complications. CONCLUSIONS: Despite the advances in vaccination, tetanus is still a present disease, whose diagnosis and rapid and adequate treatment allows patients to survive, as in the cases reported here.

Antigenic stimulation during pregnancy modifies specific iga1 and iga2 subclasses in human colostrum according to the chemical composition of the antigen

ABSTRACT Background: Several studies have evaluated the effect of infectious diseases and vaccine protocols during pregnancy on maternal milk immunoglobulin (Ig) levels, to understand the protection conferred by lactation on newborns. Colostrum is the primary source of maternal IgA for the newborn. IgA participates in protection mechanisms in the neonate's mucosa. In humans, IgA has two subclasses with differential anatomical distribution among mucosal compartments. Total IgA levels in maternal milk vary after antigen stimulation and have differential affinities in function of the chemical composition of the antigens. We studied the effect of antigenic stimulation during pregnancy on the concentrations of specific IgA1 and IgA2 subclasses in human colostrum. Methods: We analyzed data from 113 women in Mexico City and compared the amount of IgA subclasses in colostrum against three antigens: two from vaccine protocols (tetanus toxoid and pneumococcal polysaccharides) and lipopolysaccharide, a ubiquitous antigen in the gastrointestinal tract. Results: In agreement with the previous reports, we showed that IgA1 from colostrum mainly recognized protein antigens; in sharp contrast, IgA2 was mostly directed against polysaccharide antigens. These levels increased in women who had previous contacts through vaccination or infections during pregnancy. Conclusions: Antigen interaction during pregnancy increased the amount of specific IgA subclasses, depending on the chemical composition of the antigen.

Synthetic Cannabinoid-Induced Immunosuppression Augments Cerebellar Dysfunction in Tetanus-Toxin Treated Mice

Synthetic cannabinoids are one of most abused new psychoactive substances. The recreational use of abused drug has aroused serious concerns about the consequences of these drugs on infection. However, the effects of synthetic cannabinoid on resistance to tetanus toxin are not fully understood yet. In the present study, we aimed to determine if the administration of synthetic cannabinoids increase the susceptibility to tetanus toxin-induced motor behavioral deficit and functional changes in cerebellar neurons in mice. Furthermore, we measured T lymphocytes marker levels, such as CD8 and CD4 which against tetanus toxin. JWH-210 administration decreased expression levels of T cell activators including cluster of differentiation (CD) 3ε, CD3γ, CD74p31, and CD74p41. In addition, we demonstrated that JWH-210 induced motor impairment and decrement of vesicle-associated membrane proteins 2 levels in the cerebellum of mice treated with tetanus toxin. Furthermore, cerebellar glutamatergic neuronal homeostasis was hampered by JWH-210 administration, as evidenced by increased glutamate concentration levels in the cerebellum. These results suggest that JWH-210 may increase the vulnerability to tetanus toxin via the regulation of immune function.

Tetanus toxin fragment C fused to flagellin makes a potent mucosal vaccine

PURPOSE: Recombinant subunit vaccines provide safe and targeted protection against microbial infections. However, the protective efficacy of recombinant subunit vaccines tends to be less potent than the whole cell vaccines, especially when they are administered through mucosal routes. We have reported that a bacterial flagellin has strong mucosal adjuvant activity to induce protective immune responses. In this study, we tested whether FlaB could be used as a fusion partner of subunit vaccine for tetanus. MATERIALS AND METHODS: We constructed fusion proteins consisted with tetanus toxin fragment C (TTFC), the nontoxic C-terminal portion of tetanus toxin, and a Toll-like receptor 5 agonist from Vibrio vulnificus (FlaB). Mice were intranasally administered with fusion protein and protective immune responses of the vaccinated mice were analyzed. RESULTS: FlaB-TTFC recombinant protein induced strong tetanus-specific antibody responses in both systemic and mucosal compartments and prolonged the survival of mice after challenge with a supra-lethal dose of tetanus toxin. CONCLUSION: This study establishes FlaB as a successful fusion partner for recombinant subunit tetanus vaccine applicable through mucosal route, and it further endorses our previous observations that FlaB could be a stable adjuvant partner for mucosal vaccines.

Dimensionamiento de los sistemas de microfiltración y ultrafiltración para la producción de la toxina tetánica elaborada en el Instituto Nacional de Higiene Rafael Rangel / Microfiltration and ultrafiltration systems dimension for using in tetanus toxin production in the Instituto Nacional de Higiene "Rafael Rangel"

Se evaluó el uso de la tecnología de Flujo de Filtración Tan gencial (FFT), para obtener la toxina tetánica a partir de cultivos de la bacteria Clostridium tetani, usando el proceso de Micro filtración (MF), para eliminar el paquete celular y posteriormente, a partir del filtrado obtenido, concentrar y diafiltrar la Toxina Tetánica usando el proceso de Ultrafiltración (UF). Se determinaron las características de los filtros, condiciones de trabajo y el dimensionamiento de los equipos a adquirir para la nueva producción industrial de Toxina Tetánica. Se evaluaron el flujo, tiempo, rendimiento del proceso y las características del producto obtenido. Utilizando cultivos con Toxina Tetánica en un equipo de filtración de laboratorio, diseñado para producir el efecto de FFT. Se seleccionó las membranas tipo cassettes, formato Suspended Screen, porosidad 0,2μm, como las adecuadas para el proceso de MF, ya que mostraron un 100% de transmisión de la Toxina Tetánica, ausencia de restos celulares y flujo promedio de filtrado de 73.30 L/m2h. Así mismo, se seleccionaron las membranas tipo cassettes, formato Omega, porosidad 50 y 70 kDa, como las adecuadas para el proceso de UF, ya que mostraron 100% de recuperación de la toxina, ausencia de toxina en el filtrado y adecuados flujos de filtrado (106,7 y 104,4 L/m2h, respectivamente). Estos resultados permitieron dimensionar, considerando las variables a utilizar en la producción industrial (Volumen 650 a 950 litros, tiempo de procesos, 3 horas), el área de filtración de los equipos de MF y UF a adquirir, estimados en 20m2 y 5m2, respectivamente.

Tangential Flow Filtration (TFF) technology was evaluated to process tetanus toxin which is produced by Clostridium tetani bacterium. Microfiltration (MF) is used to retain cells while allowing passage of the toxin to the filtrate stream. The filtrate is co - llected and further processed by Ultrafiltration (UF) to concentrate the toxin and to maximize the wash of small species by a Dia filtration step. Both, MF and UF processes were evaluated to specify the filters and corresponding critical process parameters to scale-up the application. As part of the evaluation, flow ra te, processing time, yield and product attributes were characterized. The cell harvest containing the tetanus toxin was processed using a laboratory scale TFF system designed to product the TFF effect. The evaluation demonstrated that a cassette in sus pended screen format and membrane with 0.2μm pore is the right selection for the MF step. It showed 100% of toxin transmission without the presence of cellular debris and average process flux of 73.30 L/m2h. The UF step was conducted using the same system with cassettes in me dium screen format with pores of 50 and 70kDa. It showed 100% retention of the toxin with a process flux of 106,7 and 104,4L/m2h, respectively. To maximise product retention during UF, the 50 kDa membrane was selected. These results were used to scale-up the application to process the industrial volume of 650 a 950 liters in 3 hours of processing time. Membrane area sizing of MF and UF to be acquired is estimated in 20m2 and 5m2, respectively.

Detección inmunoenzimática de la toxina de la bacteria Clostridium tetani: una alternativa a las pruebas biológicas con ratones / Immunoenzimatic detection of the Clostridium tetani bacterial toxin: an alternative to mice bioassays

Cell-free extracts from 20 strains of Clostridium tetani isolated from soil samples, were tested for tetanus toxin production using an enzyme immunoassay. All the extracts were classified as positive for the toxin presence, and eight of them showed absorbance values corresponding to tetanus toxin concentrations between 3.2 and 88 ng/ml; thus, they fell within the linear absorbance range (0.135-0.317). All dilutions of toxin used to obtain the calibration curve (0.0071 to 1.1 ng) were lethal for mice.

Obtención de la toxina tetánica a partir de hidrolizado de caseina de producción nacional

La producción de toxoide tetánico se realiza a partir de la toxina tetánica destoxificada y purificada por métodos químicos. Un buen rendimiento de la toxina tetánica reviste gran importancia, pues éste es fundamental para obtener el número de dosis necesarias a un bajo costo. Se presentan los resultados obtenidos en la producción de toxina tetánica a partir de hidrolizado de caseína de producción nacional, mediante la realización de pruebas químicas, microbiológicas e inmunológicas, y se comprueba que el rendimiento es superior al obtenido con el hidrolizado de caseína de importación (triptona T, Oxoid).

The production of the tetanus toxoid is developed from the chemically detoxified and purified tetanus toxin. A good yielding of the tetanus toxin has a great importances, since it is fundamental to obtain the amount of necessary doses at a low cost. Here the authors present the results of the production of the tetanus toxin from the nationally produced casein hydrolysate, through chemical, microbiological, and immunological tests, and it is confirmed that the yield is higher than the one obtained with the imported casein hydrolysate (triptone T, Oxoid).