Distinctive Immunomodulatory and Inflammatory Properties of the Escherichia coli Type II Heat-Labile Enterotoxin LT-IIa and Its B Pentamer following Intradermal Administration

ABSTRACTThe type I and type II heat-labile enterotoxins (LT-I and LT-II) are strong mucosal adjuvants when they are coadministered with soluble antigens. Nonetheless, data on the parenteral adjuvant activities of LT-II are still limited. Particularly, no previous study has evaluated the adjuvant effects and induced inflammatory reactions of LT-II holotoxins or their B pentameric subunits after delivery via the intradermal (i.d.) route to mice. In the present report, the adjuvant and local skin inflammatory effects of LT-IIa and its B subunit pentamer (LT-IIaB5) were determined. When coadministered with ovalbumin (OVA), LT-IIa and, to a lesser extent, LT-IIaB5exhibited serum IgG adjuvant effects. In addition, LT-IIa but not LT-IIaB5induced T cell-specific anti-OVA responses, particularly in respect to induction of antigen-specific cytotoxic CD8+T cell responses. LT-IIa and LT-IIaB5induced differential tissue permeability and local inflammatory reactions after i.d. injection. Of particular interest was the reduced or complete lack of local reactions, such as edema and tissue induration, in mice i.d. inoculated with LT-IIa and LT-IIaB5,respectively, compared with mice immunized with LT-I. In conclusion, the present results show that LT-IIa and, to a lesser extent, LT-IIaB5exert adjuvant effects when they are delivered via the i.d. route. In addition, the low inflammatory effects of LT-IIa and LT-IIaB5in comparison to those of LT-I support the usefulness of LT-IIa and LT-IIaB5as parenterally delivered vaccine adjuvants.

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Intradermal Administration of the Type II Heat-Labile Enterotoxins LT-IIb and LT-IIc of Enterotoxigenic Escherichia coli Enhances Humoral and CD8+ T Cell Immunity to a Co-Administered Antigen

PLoS ONE ◽

10.1371/journal.pone.0113978 ◽

2014 ◽

Vol 9 (12) ◽

pp. e113978 ◽

Cited By ~ 7

Author(s):

John C. Hu ◽

Camila Mathias-Santos ◽

Christopher J. Greene ◽

Natalie D. King-Lyons ◽

Juliana F. Rodrigues ◽

...

Keyword(s):

Escherichia Coli ◽

T Cell ◽

Cd8 T Cell ◽

T Cell Immunity ◽

Enterotoxigenic Escherichia Coli ◽

Type Ii ◽

Heat Labile ◽

Cell Immunity ◽

Intradermal Administration

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Biochemical and structural characterization of the novel sialic acid-binding site of Escherichia coli heat-labile enterotoxin LT-IIb

Biochemical Journal ◽

10.1042/bcj20160575 ◽

2016 ◽

Vol 473 (21) ◽

pp. 3923-3936 ◽

Cited By ~ 3

Author(s):

Dani Zalem ◽

João P. Ribeiro ◽

Annabelle Varrot ◽

Michael Lebens ◽

Anne Imberty ◽

...

Keyword(s):

Escherichia Coli ◽

Binding Site ◽

Cholera Toxin ◽

Carbohydrate Binding ◽

Type I ◽

Type Ii ◽

E Coli ◽

B Subunit ◽

Heat Labile ◽

B Subunits

The structurally related AB5-type heat-labile enterotoxins of Escherichia coli and Vibrio cholerae are classified into two major types. The type I group includes cholera toxin (CT) and E. coli LT-I, whereas the type II subfamily comprises LT-IIa, LT-IIb and LT-IIc. The carbohydrate-binding specificities of LT-IIa, LT-IIb and LT-IIc are distinctive from those of cholera toxin and E. coli LT-I. Whereas CT and LT-I bind primarily to the GM1 ganglioside, LT-IIa binds to gangliosides GD1a, GD1b and GM1, LT-IIb binds to the GD1a and GT1b gangliosides, and LT-IIc binds to GM1, GM2, GM3 and GD1a. These previous studies of the binding properties of type II B-subunits have been focused on ganglio core chain gangliosides. To further define the carbohydrate binding specificity of LT-IIb B-subunits, we have investigated its binding to a collection of gangliosides and non-acid glycosphingolipids with different core chains. A high-affinity binding of LT-IIb B-subunits to gangliosides with a neolacto core chain, such as Neu5Gcα3- and Neu5Acα3-neolactohexaosylceramide, and Neu5Gcα3- and Neu5Acα3-neolactooctaosylceramide was detected. An LT-IIb-binding ganglioside was isolated from human small intestine and characterized as Neu5Acα3-neolactohexaosylceramide. The crystal structure of the B-subunit of LT-IIb with the pentasaccharide moiety of Neu5Acα3-neolactotetraosylceramide (Neu5Ac-nLT: Neu5Acα3Galβ4GlcNAcβ3Galβ4Glc) was determined providing the first information for a sialic-binding site in this subfamily, with clear differences from that of CT and LT-I.

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Structure of the two promoters of the human lck gene: differential accumulation of two classes of lck transcripts in T cells

Molecular and Cellular Biology ◽

10.1128/mcb.9.5.2173-2180.1989 ◽

1989 ◽

Vol 9 (5) ◽

pp. 2173-2180

Author(s):

T Takadera ◽

S Leung ◽

A Gernone ◽

Y Koga ◽

Y Takihara ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Cell Lines ◽

Carcinoma Cell ◽

Human Peripheral Blood ◽

Specific Gene ◽

Type I ◽

Type Ii ◽

Carcinoma Cell Lines ◽

Human T Cell

The human T-cell- or lymphocyte-specific gene, lck, encodes a tyrosine kinase and is a member of the src family. In this report we demonstrate that there are two classes of human lck transcripts (types I and II), containing different 5'-untranslated regions, which are expressed from two distinct promoters. No apparent sequence similarity was observed between the 5'-flanking regions of the two promoters. The expression of lck in human T-cell leukemia and carcinoma cell lines and in human peripheral blood T lymphocytes was examined by S1 nuclease and primer extension mapping and by Northern (RNA) blot analysis of total cellular RNA. The following results were obtained. (i) Two RNA start sites in the downstream promoter were used to generate type I transcripts. (ii) The major human type I start site has not been described for the mouse. (iii) At least five RNA start sites in the upstream promoter were used to generate type II transcripts. (iv) In T cells and in two colon carcinoma cell lines, type II transcripts were present in higher amounts than type I transcripts. (v) In T cells treated with phytohemagglutinin, tetradecanoylphorbol acetate, and cyclosporin A, the modulation of lck expression was associated primarily with changes in levels of type II transcripts. The above results suggest that the two human lck promoters are utilized differentially and may be regulated independently during certain physiological states.

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Mutants of Type II Heat-Labile Enterotoxin LT-IIa with Altered Ganglioside-Binding Activities and Diminished Toxicity Are Potent Mucosal Adjuvants

Infection and Immunity ◽

10.1128/iai.01009-06 ◽

2006 ◽

Vol 75 (2) ◽

pp. 621-633 ◽

Cited By ~ 20

Author(s):

Hesham F. Nawar ◽

Sergio Arce ◽

Michael W. Russell ◽

Terry D. Connell

Keyword(s):

Escherichia Coli ◽

Immune Responses ◽

Binding Activity ◽

Enzyme Linked Immunosorbent Assay ◽

Type I ◽

Type Ii ◽

Heat Labile ◽

Enhanced Expression ◽

Adhesin Protein ◽

And Function

ABSTRACT The structure and function LT-IIa, a type II heat-labile enterotoxin of Escherichia coli, are closely related to the structures and functions of cholera toxin and LT-I, the type I heat-labile enterotoxins of Vibrio cholerae and enterotoxigenic Escherichia coli, respectively. While LT-IIa is a potent systemic and mucosal adjuvant, recent studies demonstrated that mutant LT-IIa(T34I), which exhibits no detectable binding activity as determined by an enzyme-linked immunosorbent assay, with gangliosides GD1b, GD1a, and GM1 is a very poor adjuvant. To evaluate whether other mutant LT-IIa enterotoxins that also exhibit diminished ganglioside-binding activities have greater adjuvant activities, BALB/c mice were immunized by the intranasal route with the surface adhesin protein AgI/II of Streptococcus mutans alone or in combination with LT-IIa, LT-IIa(T14S), LT-IIa(T14I), or LT-IIa(T14D). All three mutant enterotoxins potentiated strong mucosal immune responses that were equivalent to the response promulgated by wt LT-IIa. All three mutant enterotoxins augmented the systemic immune responses that correlated with their ganglioside-binding activities. Only LT-IIa and LT-IIa(T14S), however, enhanced expression of major histocompatibility complex class II and the costimulatory molecules CD40, CD80, and CD86 on splenic dendritic cells. LT-IIa(T14I) and LT-IIa(T14D) had extremely diminished toxicities in a mouse Y1 adrenal cell bioassay and reduced abilities to induce the accumulation of intracellular cyclic AMP in a macrophage cell line.

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Type I NKT cells protect (and type II NKT cells suppress) the host's innate antitumor immune response to a B-cell lymphoma

Blood ◽

10.1182/blood-2007-05-092866 ◽

2008 ◽

Vol 111 (12) ◽

pp. 5637-5645 ◽

Cited By ~ 106

Author(s):

Gourapura J. Renukaradhya ◽

Masood A. Khan ◽

Marcus Vieira ◽

Wenjun Du ◽

Jacquelyn Gervay-Hague ◽

...

Keyword(s):

T Cell ◽

B Cell ◽

Cell Lymphoma ◽

B Cell Lymphoma ◽

Nkt Cells ◽

Type I ◽

Type Ii ◽

Nkt Cell ◽

Tumor Bearing

Abstract Natural killer T (NKT) cells are a T-cell subpopulation known to possess immunoregulatory functions and recognize CD1d molecules. The majority of NKT cells express an invariant T-cell receptor (TCR) α chain rearrangement (Vα14Jα18 in mice; Vα24Jα18 in humans) and are called type I NKT cells; all other NKT cells are type II. In the current study, we have analyzed the roles for these NKT-cell subsets in the host's innate antitumor response against a murine B-cell lymphoma model in vivo. In tumor-bearing mice, we found that type I NKT cells conferred protection in a CD1d-dependent manner, whereas type II NKT cells exhibited inhibitory activity. Pro- and anti-inflammatory cytokines secreted by splenocytes from tumor-bearing mice correlated with tumor progression. Myeloid cells (CD11b+Gr1+) were present in large numbers at the tumor site and in the spleen of tumor-bearing type I NKT–deficient mice, suggesting that antitumor immunosurveillance was inhibited by CD11b+Gr1+ cells. Overall, these data suggest that there are distinct roles for NKT-cell subsets in response to a B-cell lymphoma in vivo, pointing to potential novel targets to be exploited in immunotherapeutic approaches against blood cancers.

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Molecular analysis of the T-cell acute lymphoblastic leukemia- associated t(1;7)(p34;q34) that fuses LCK and TCRB

Blood ◽

10.1182/blood.v84.4.1232.bloodjournal8441232 ◽

1994 ◽

Vol 84 (4) ◽

pp. 1232-1236 ◽

Cited By ~ 1

Author(s):

RC Burnett ◽

MJ Thirman ◽

JD Rowley ◽

MO Diaz

Keyword(s):

T Cell ◽

Lymphoblastic Leukemia ◽

Receptor Gene ◽

Type I ◽

Type Ii ◽

Transcriptional Enhancer ◽

Recognition Sequence ◽

Chromosomal Breakage ◽

Rnase Protection

Previously we had characterized the t(1;7)(p34;q34) translocation from HSB-2. This translocation fused the beta T-cell receptor gene (TCRB) constant region and transcriptional enhancer with the type I transcription unit of the LCK gene on the derivative 1 [der(1)] chromosome. The type II promoter was translocated to the der(7) chromosome. Regarding the mechanism of the t(1;7) in HSB-2, we identified an alternating purine-pyrimidine tract (G-T)17 at the 1p34/LCK breakpoint. Additionally, sequence analysis of both breakpoint junctions provided data that implicate the V(D)J recombinase in formation of the t(1;7). A heptamer-nonamer recognition sequence with a 12-bp spacer was found in the immediate vicinity of the 1p34/LCK breakpoint and, thus, chromosomal breakage at 1p34 may be explained as resulting from recombinase activity. Because phosphorylation of Tyr-505 in vivo regulates the tyrosine kinase activity of p56lck we amplified a region from LCK exon 12 that contains the codon for Tyr-505 and showed no mutation of this codon in HSB-2 DNA and, therefore, p56lck in HSB-2 is not activated by mutation of Tyr-505. We have analyzed LCK gene expression in HSB-2 and SUP-T12 cell lines. RNase protection analysis identified almost exclusively type I transcripts in HSB-2. An independent t(1;7) in SUP-T12 also resulted in the juxtaposition of LCK to TCRB. The breakpoint in SUP-T12 occurred 2 kb 5′ of the type II promoter, leaving an intact LCK gene on the der(1) chromosome. RNase protection analysis identified both type I and type II LCK transcripts in a 3:1 ratio in SUP-T12. Factors other than proximity to the TCRB enhancer must affect promoter utilization in this cell line.

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Synthetic peptide-based immunoassays for distinguishing between human T-cell lymphotropic virus type I and type II infections in seropositive individuals.

Journal of Clinical Microbiology ◽

10.1128/jcm.29.10.2253-2258.1991 ◽

1991 ◽

Vol 29 (10) ◽

pp. 2253-2258 ◽

Cited By ~ 27

Author(s):

R B Lal ◽

W Heneine ◽

D L Rudolph ◽

W B Present ◽

D Hofhienz ◽

...

Keyword(s):

T Cell ◽

Virus Type ◽

Synthetic Peptide ◽

Type I ◽

Type Ii ◽

Human T Cell

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Characterization of antigen-presenting cells induced by intragastric immunization with recombinant chimeric immunogens constructed from Streptococcus mutans AgI/II and type I or type II heat-labile enterotoxins

Molecular Oral Microbiology ◽

10.1111/j.2041-1014.2011.00608.x ◽

2011 ◽

Vol 26 (3) ◽

pp. 200-209 ◽

Cited By ~ 5

Author(s):

W. Zhao ◽

Z. Zhao ◽

M.W. Russell

Keyword(s):

Streptococcus Mutans ◽

Antigen Presenting Cells ◽

Type I ◽

Type Ii ◽

Heat Labile ◽

Antigen Presenting

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Congenital Dyserythropoietic Anemia Type II: Excessive Endoplasmic Reticulum in Erythroid Cells and Mitochondrial Inclusions of Hepatic Cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100065511 ◽

1971 ◽

Vol 29 ◽

pp. 294-295

Author(s):

George Hug ◽

K. Y. Wong ◽

Beatrice Lampkin

Keyword(s):

Bone Marrow ◽

Human Serum ◽

Present Report ◽

Initial Study ◽

Red Cells ◽

Type I ◽

Red Cell ◽

Type Ii ◽

Erythroid Cells ◽

Congenital Dyserythropoietic Anemia

Congenital dyserythropoietic anemia (CDA) as described in 1966 was characterized by (i) erythroblastic multinuclearity and (ii) lysis of the patient's red cells in acidified compatible normal human serum. This condition has since been labeled CDA Type II to distinguish it from a similar entity, CDA Type I, with erythroblastic multinuclearity but without red cell lysis in acidified human serum. According to this classification, our initial study of bone marrow ultrastructure in CDA concerned a girl with Type II. Her bone marrow contained erythroid cells with excessive cytoplasmic membranes and multiple nuclei. The present report illustrates this observation. The patient was a 12 year old white girl with congenital anemia and benign recurrent jaundice. Hemolysis was not present since Cr51 red cell survival time was normal. Bone marrow aspirates (Figure 1, 2 and 4) circulating red cells (Figure 3) and hepatic biopsy specimens were examined. The markers indicate 0.5 microns and N designates nucleus. The myeloid series was normal. Figure 1 shows a representative polychromatophilic normoblast.

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