Disease relevance of CTBS

• These results suggest that rPsaA coencapsulated with CTB can be used as an oral vaccine to induce cross-protective immunity for the prevention of pneumococcal infection [1].
• Herein, we evaluate CpG ODN with intranasal (IN) delivery of purified hepatitis B surface antigen (HBsAg), relative to and in combination with CT, Escherichia coli heat labile enterotoxin (LT), the B subunit of CT (CTB), and a nontoxic derivative of LT (LTK63) [2].
• The non-toxic B subunit of cholera toxin (CTB) and E. coli heat-labile toxin mutant proteins with reduced toxicity (LTR72) or no toxicity (LTK63) were used as adjuvants for epidermal powder immunization (EPI) with an influenza vaccine [3].
• The B subunit portion of cholera toxin (CTB) is a safe and effective oral immunizing agent in humans, affording protection against both cholera and diarrhoea caused by enterotoxigenic Escherichia coli producing heat-labile toxin (LT) (Clemens et al., 1986; 1988) [4].
• Synthesis of CTB-LF monomers and their assembly into biologically active CTB-LF fusion protein pentamers in potato tuber tissues demonstrates the feasibility of using edible plants for production and delivery of adjuvanted LF protein for CTB-mediated immunostimulation of mucosal immune responses against anthrax toxin [5].

High impact information on CTBS

• The two lots of the ETEC vaccine induced similar rates of serum antibody responses to CTB and CFA/I which were less frequent than the ASC responses to the same antigens [6].
• Both lots of vaccine stimulated a rate of significant antibody-secreting cell (ASC) response to CTB and to colonization factor antigen I (CFA/I) after one or two doses, ranging from 85 to 100% and from 81 to 100%, respectively [6].
• As demonstration that the seminal plasma was not removing G(M1), sperm exposed to seminal plasma were fixed before CTB addition, and again displayed fluorescence over the acrosome [7].
• Using the pentameric B subunit of cholera toxin (CTB), we found G(M1) to be restricted to the plasma membrane overlying the acrosome in the heads of live murine sperm [7].
• To determine whether some component of seminal plasma was interfering with the ability of CTB to access G(M1), we incubated epididymal mouse sperm with fluid from murine seminal vesicles and epididymal bull sperm with bovine seminal plasma [7].

Biological context of CTBS

• The human chitobiase gene ( CTB S) is approximately 20 kb comprising seven exons varying from 0.1 to 2.3 kb and six introns of 0.3 to 8 kb [8].
• These results indicate (i) that CTB has no cytostatic effect on human T cells, (ii) that CT affects proliferation and cytokine production by two different signal pathways, and (iii) that CT might interact with a signal pathway generated through or influenced by CD45 [9].
• Here, we investigated if a nonconjugated form of CTB enhances the induction of immune tolerance after oral insulin administration [10].
• The amino acid sequence of 1841 toxin B subunit was identical with that of KT25 CTB, corresponding to the DNA sequence of ctxB from El Tor strains of the seventh pandemic [11].
• We here expand these findings by describing overexpression of CTB by a constitutive tacP promoter as well as by the T7 RNA-polymerase promoter, and also by describing gene fusions leading to overexpression of several hybrid proteins between heat-stable E. coli enterotoxin (STa)-related peptides to either the amino or carboxy ends of CTB [4].

Anatomical context of CTBS

• We have studied how cholera toxin (CT) and its non-toxic cell-binding B-subunit (CTB) affect the activation of pure human T cells in an anti-CD3-driven system [9].
• Following oral administration of CTB-GFP expressing leaf material to mice, GFP was observed in the mice intestinal mucosa, liver, and spleen in fluorescence and immunohistochemical studies, while CTB remained in the intestinal cell [12].
• We measured transmural myofiber angle distribution in the LV compact myocardium in Hamburger-Hamilton stages 21, 27, 31, and 36 chick embryos during normal development or following either left atrial ligation (LAL; LV hypoplasia model) or conotruncal banding (CTB; LV hyperplasia model) [13].

Analytical, diagnostic and therapeutic context of CTBS

• Protein refolding was carried out on this column, during procedure purification, followed by dialysis against CTBS and then by gel filtration for separation of the active dimmer [14].
• When conjugated to various proteins, the nontoxic B-chain of cholera toxin (CTB) significantly increases the ability of these proteins to induce immunological tolerance after oral administration [10].
• We have as a model protein antigen used human gammaglobulin (HGG) for admixture with or chemical conjugation to recombinantly produced CTB and LTB, respectively, and measured antigen-specific local secretory IgA antibodies in saponin extracts from intestine and lung tissue by ELISA following intra-nasal (i.n.) or per-oral (p.o.) immunization [15].
• Titration of the CTB concentration in this system revealed that an insulin : CTB ratio of 100 : 1 was optimal for the induction of bystander suppression [10].

References