Objective To prepare monoclonal antibodies against bovine CD4 and identify their basic biological characteristics. Methods Recombinant bovine CD4 (rHis-BoCD4 and rGST-BoCD4) was successfully expressed and purified by constructing a prokaryotic plasmid of bovine CD4 gene. The bovine CD4 monoclonal antibody was produced using hybridoma technology. The subtype and potency of the monoclonal antibody were identified and analyzed by ELISA, while specificity was analyzed through indirect immunofluorescence assay (IFA) and Western-blot. Results Four hybridoma cell lines, namely, 1H4, 6A10, 3F9 and 4G10, stably secreting monoclonal antibodies against BoCD4 were successfully obtained. The subclasses of the monoclonal antibodies subclass 6A10 was IgG2b and the rest of the monoclonal antibodies were of IgM type. Western-blot results showed that the four anti-bovine CD4 mAb strains were able to specifically bind to the bovine CD4 protein expressed in vitro. Indirect immunofluorescence assay showed that four monoclonal antibodies were able to specifically recognize the natural bovine CD4 protein. Flow cytometry assay showed that 3F9 was best to recognize bovine natural CD4 molecules. Conclusion Four monoclonal antibody strains with high specificity to natural bovine CD4 protein were successfully prepared, which lays the foundation for the subsequent studies on the function of bovine CD4 and diagnosis and treatment of bovine T-lymphocyte diseases.
Animals ; Antibodies, Monoclonal/isolation & purification* ; Cattle ; CD4 Antigens/genetics* ; Hybridomas/immunology* ; Antibody Specificity/immunology* ; Mice ; Mice, Inbred BALB C ; Enzyme-Linked Immunosorbent Assay ; Fluorescent Antibody Technique, Indirect

Nonhuman primates(NHPs)are susceptible hosts of tuberculosis(TB).After infection,TB not only spreads among monkey populations but can also spread to humans.An effective vaccine to protect NHPs from TB has not been developed.Although prevention and control protocols have matured and reduced the incidence of TB among NHPs in captivity,outbreaks continue to occur.This article summarizes the worldwide epidemiological situation of TB in monkeys in captivity and in the wild,analyzes the advantages and disadvantages of commonly used detection method,and summarizes the most common practices of TB prevention and control in NHPs.Our findings indicate that TB poses a great threat to NHPs,underscoring the importance of raising awareness of TB among NHP breeding workers and managers.Additionally,our result provide a basis for improving current management procedures and offer valuable insights for TB diagnosis,prevention,and control in NHPs in China.

Salmonella Derby is recognized as a major human food-borne pathogen causing food poisoning,septicaemia and other symptoms.Meanwhile,it can represent a severe threat to livestock breeding and health.The objective of this review is to summarize novel research progress on epidemic,genomics,pathogenic mechanism of Salmonella Derby for provide reference to related research.

Salmonella is an important zoonosis.China is the largest pork consumer.Contaminated pork is the main source of Salmonella disease at home and abroad.There are many swine Salmonella vaccine in use in Europe.Now the current swine Salmonella vaccine is a live attenuated vaccine,Salmonella can reduce colonization in pigs,and can induce immune response efficiently after the two immunizations.The control effect is poor,at this stage of swine vaccine cross protection research,type of Salmonella and vaccine antigen are not the same.This paper reviews the research progress of swine Salmonella vaccine.

Tuberculosis (TB) is an infectious disease endangering people’s health around the world ,and diagnosis and ra‐tional treatment are the key to control TB .However ,currently there is no diagnostic golden standard for latent tuberculosis in‐fection (LTBI) .The tuberculin skin test and IFN‐gamma release analysis are regarded as effective methods for TB diagnosis , which is based on host’s cellular immune response to mycobacterial antigens .But the two methods are not perfect ;neither test can make a clear distinction between latent infection and active TB .Flow Cytometry (FCM ) has been widely used in the field of clinical medicine .In recent years ,substantial advances have been achieved in the fields of TB diagnosis and evaluation of treat‐ment efficacy by using the FCM intracellular cytokine detection technology .In this paper ,we will review the latest progress in tuberculosis diagnosis research by using flow cytometry in recent years .

Salmonella enterica serovar Choleraesuis strain C500 is a live attenuated vaccine that has been widely used in Chi‐na for over 50 years to prevent piglet paratyphoid .However ,as C500 is obtained by chemical methods ,the genetic background of this strain remained unclear .In this study ,we compared the genomic differences between the virulent reference strain C 78‐2 and C500 by suppression subtractive hybridization combined with the mirror orientation selection method (MOS‐SSH ) .Six genes (asr ,ydgF ,ydgD ,ydgE ,rpoS ,and ptsG) were lost in C500 strain .Using real‐time PCR analysis ,we demonstrated that the genes regulated by rpoS ,a vital transcriptional regulator playing an important role in Salmonella infection ,were downregulated in C500 .Additionally ,the virulence of the rpoS mutant strain C78‐2ΔrpoS was 100 000 times lower than the parental strain in BALB/c mice .So loss of rpoS gene is the major factor leading to the attenuation of C500 strain .

Salmonella is a pathogenic bacteria to human and animals ,which can cause seriously complication and death . Salmonella pathogenicity is from the reactions of SP‐1 and SP‐2 T3SS effector proteins .In this paper ,the functions of different T3ss effector proteins in different infection periods is reviewed to provide a reference for further understanding the pathogenesis mechanisms of Salmonella .

Listeriamonocytogenes is a facultative intracellular bacterium that enters professional antigen presenting cells , presents passenger antigens to the major histocompatibility complex class I and II pathways ,then elicits CD+4 and CD+8 T-cell-mediated immune responses .It was demonstrated that attenuated Listeriamonocytogenes as a novel live vaccine vector in deliv-ering tumor antigens of cervical cancer and melanoma etc .,could induce strong protective immune response ,and shows effec-tive antitumor immunotherapeutics .This review discussed the characteristics of immune responses elicited by Listeria monocy-togenes ,and the progress of its antitumor immunotherapeutics as delivery vaccine vector .

Proteins encoded by regions of difference (RD) of Mycobacterium tuberculosis (MTB) constitute a potential source of specific antigens for vaccine development and immunodiagnosis .In the present study ,four genes named nrdF1 , pe_pgrs35 ,rv1985c ,and rv1986 from RD2 of MTB were cloned and overexpressed in E .coli with the induction of IPTG .Western blotting assay showed that these recombinant fusion proteins could well react with anti-His tag monoclonal antibody ,which in-dicated their good immunoreactivity .The serodiagnosis potential applications of these four proteins in bovine tuberculosis were further evaluated .An indirect ELISA assay was established by using fusion proteins as coating antigens for detection of their specific antibodies in bovine sera .The positive rates were 7 .35% in NrdF1 ,22 .06% in PE_PGRS35 ,16 .18% in Rv1985c and 16 .18% in Rv1986 respectively .All the results suggest that these fusion proteins have the potential application in serodiagnosis of bovine tuberculosis .

The prevalence of human and animal listeriosis for nearly 11 years in China was investigated in this study . The literature information about listeriosis in China from 2002 to 2012 was collected through retrieval system to make clinical and epidemiological statistical analysis of listeriosis .Cases of listeriosis were reported in 27 (79% ) provinces of China .The re-sult showed that animal listeriosis was reported for 123 times ,among these reports ,most were from pigs (39% ) ,and the sheep was in second place .Central nervous system infection was the main clinical manifestation of listeriosis in animals (72% ) . For human listeriosis ,84 clinical cases of listeriosis were reported ,including 35% cases in non-perinatal stage and 65% cases in perinatal stage .The main clinical manifestation of listeriosis was septicemia (51% ) .According to the result of investigation about listeriosis based on literatures information ,Listeriamonocytogenes caused humans and animals listeriosis annually ,which were reported in most provinces of China .The epidemic characteristics for listeriosis suggested that it was essential to strength-en the prevention and control of listeriosis .