VIOLIN: Vaccine Investigation and Online Information Network

Entamoeba histolytica

Table of Contents

General Information
Vaccine Related Pathogen Genes
1. ARP2 (Protective antigen)
2. CEL-170/4 (Protective antigen)
3. CP3 (Protective antigen)
4. Gal/GalNAc lectin (Protective antigen)
5. gEh29 (Protective antigen)
6. SREHP (Protective antigen)
Vaccine Information
References

I. General Information

1. NCBI Taxonomy ID:

5759

2. Disease:

Amoebiasis

3. Introduction

Entamoeba histolytica is an anaerobic parasitic protozoan, part of the genus Entamoeba. Predominantly infecting humans and other primates, E. histolytica is estimated to infect about 50 million people worldwide. Many older textbooks state that 10% of the world population is infected, but these figures predate the recognition that at least 90% of these infections were due to a second species, E. dispar. Mammals such as dogs and cats can become infected transiently, but are not thought to contribute significantly to transmission.

The active (trophozoite) stage exists only in the host and in fresh loose faeces; cysts survive outside the host in water, soils and on foods, especially under moist conditions on the latter. The cysts are readily killed by heat and by freezing temperatures, and survive for only a few months outside of the host. When cysts are swallowed they cause infections by excysting (releasing the trophozoite stage) in the digestive tract. The trophozoite stage is readily killed in the environment and cannot survive passage through the acidic stomach to cause infection. Symptoms can include fulminating dysentery, bloody diarrhea, weight loss, fatigue, abdominal pain, and amoeboma (Wiki: Entamoeba histolytica).

4. Microbial Pathogenesis

The amoeba can actually 'bore' into the intestinal wall, causing lesions and intestinal symptoms, and it may reach the blood stream. From there, it can reach different vital organs of the human body, usually the liver, but sometimes the lungs, brain, spleen, etc. A common outcome of this invasion of tissues is a liver abscess, which can be fatal if untreated. Ingested red blood cells are sometimes seen in the amoeba cell cytoplasm (Wiki: Entamoeba histolytica).

5. Host Ranges and Animal Models

Other than infecting humans, mammals such as dogs and cats can become infected transiently, but are not thought to contribute significantly to transmission (Wiki: Entamoeba histolytica).

6. Host Protective Immunity

It has been shown that amoeba-specific sIgA antibodies are capable of blocking parasite adherence to target cells, preventing cytotoxic activity (Carrero et al., 2010).

II. Vaccine Related Pathogen Genes

1. ARP2

Gene Name : ARP2
Sequence Strain (Species/Organism) : Entamoeba histolytica
NCBI Protein GI : AAF21857
Other Database IDs : CDD:100111
Taxonomy ID : 5807
Protein Name : acidic ribosomal protein P2
Protein pI : 4.15
Protein Weight : 11050.47
Protein Length : 179
Protein Note : Ribosomal protein P2. This subfamily represents the eukaryotic large ribosomal protein P2. Eukaryotic P1 and P2 are functionally equivalent to the bacterial protein L7/L12, but are not homologous to L7/L12. P2 is located in the L12 stalk, with proteins...; cd05833

Protein Sequence : Show Sequence

>AAF21857.1 acidic ribosomal protein P2 [Cryptosporidium parvum]
MGMKYVAAYLLCVSSGKEQPTASDIKKVLESVGIEYDQSIIDVLISNMSGKLSHEVIASGLSKLQSVPTG
GVAVSGGAAAASGAAQDSAPAEKKKEEEEEEEGDLGFSLFD

Molecule Role : Protective antigen
Molecule Role Annotation : (Priest et al., 2010)

2. CEL-170/4

Gene Name : CEL-170/4
Sequence Strain (Species/Organism) : Entamoeba histolytica
VO ID : VO_0011326
NCBI Protein GI : 401088
Taxonomy ID : 5759
Gene Strand (Orientation) : ?
Protein Name : 170 kDa surface lectin
Protein pI : 4.96
Protein Weight : 138236.38
Protein Length : 1384
Protein Note : {ECO:0000269|PubMed:2000392, ECO:0000269|PubMed:2536731}.

Protein Sequence : Show Sequence

>sp|P23502.2|SL17_ENTHI RecName: Full=170 kDa surface lectin; Flags: Precursor
MKLLLLNILLLCCLADKLNEFSADIDYYDLGIMSRGKNAGSWYHSYTHQYDVFYYLAMQPWRHFVWTTCE
TTKGNKECYKYIINEDHNLNAQQLNNIKNLDKQDFCQKEYAYPIEKYEVDWDNVPVDEQQIESVDINGKT
CFKYAAKRPLAYVYLNTKMTYATKTEAYDVCRMDFIGGRSITFRSFNNENKDFIDQYNTNTTSKCIIDVH
KNNVNTHLAIILGITDSTVIKSLQENLSLLSQLKQSRVTLYYLKDDSYATDNIKLKDLKYETLVKYTAGQ
GQVDPLVNQAKNDLFKMISDKKIKRGTMVVLMDNALGSEFNAETEFDRKNISVHTVVLNRNKDSKITYSA
LKLVSLGPHYHEFTSNSEVSTTIDELFKGIRANLTERCDRDKCSGFCDAMNRCTCPMCCENDCFYTSCDV
ETGSCIPWPKAKPKAKKECPATCVGLYECKDLEGCVVTKYNASCEPKVKCMVPYCDDDNNLKEVCKQKAN
CEADQKPSSDGYCWSYTCDETTGFCKKYKHGNLCTGKTTNCQEYVCDSEQRCTVQEKVCVKTSPYIEMSC
YVAKCNLNTGMCENRLSCDTYSSCGGDSTGSVCKCDASTGNQCKCNKVENGNYCDSSKHEICDYTGDKPK
CIVSECTEDLVRDGCLIKRCNKTSKTTYWENVDCSNTKIEFAQDGKSETMCKPYYSATCLNGQCVVQAVG
DVSNVGCGYCSMGTDNVITYHDDCDSRKSQCGNFNGKCQPNGDNSYSCVFEKDKTSSKSDNDICAECSSL
TCPADTTYRTYTYDSKTGTCKATVKPTPSCSVCEKGKFVEKSKDQKLERKVTLEDGKEYQYNIPKDCVNE
QCIPRTYVDCLANDDNFGEIYKFYLPCQAYVTATYHYSSLFNLTSYKLHLPQSEEFMKEADKEAYCTYEI
TTRECKTCSLTETKEKVEEIDLCAEETKNGGVPFKCKNNNCIIDPNFDCQPIECKIQEIVITEKDGIKTT
TCKDGTKTTCDTNNKRIEDARKAFIEGKEGIEQVECASTVCQNDNSCPIIADVEKCNQNTEVDYGCKAMT
GECDGTTYLCKFVQLTDDPSLDSEHFRTKSGVELNNACLKYKCVESKGSDGKITHKWEIDTERSNIDPKP
RNPCETATCDQTTGETIYTKKTCTVSEEFPTITPNQGRCFYCQCSYLDGSSVLTMYGETDKEYYDLDACG
NCRVWNQTDRTQQLNNHTECILAGEINNVGAIAAATTVAVVVVAVVVALIVVSIGLFKTYQLVSSAMKNA
ITTTNENAEYVGADNEATNAATYNG

Molecule Role : Protective antigen
Molecule Role Annotation : Researcherse tested the ability of the galactose-specific adherence lectin of E. histolytica to elicit a protective immune response in conjunction with Freund's incomplete and complete adjuvants. Four independent trials demonstrated complete protection from amebic liver abscess formation in 67% of lectin-immunized gerbils. The gerbil antilectin antibodies were shown by Western immunoblotting to be directed to the heavy subunit (CEL-170/4) but not the light subunit of the lectin (Petri and Ravdin, 1991).
Related Vaccine(s): E. histolytica CEL-170/4 protein vaccine

3. CP3

Gene Name : CP3
Sequence Strain (Species/Organism) : Entamoeba histolytica
NCBI Protein GI : CAA60673
Other Database IDs : CDD:214853
CDD:278538
CDD:239068
GOA:P36184
InterPro: IPR000169
InterPro: IPR000668
InterPro: IPR013128
InterPro: IPR013201
UniProtKB/UniProt: P36184
Taxonomy ID : 5759
Protein Name : cysteine proteinase
Protein pI : 6.95
Protein Weight : 31942.92
Protein Length : 370
Protein Note : pathogen;
locus EhCP3

Protein Sequence : Show Sequence

>CAA60673.1 cysteine proteinase [Entamoeba histolytica]
MFALILFVSLACANEVAFKQWAATHNKVFANRAEYLYRFAVFLDNKKFVEANANTELNVFADMTHEEFIQ
THLGMTYEVPETTSNVKAAVKAAPESVDWRSIMNPAKDQGQCGSCWTFCTTAVLEGRVNKDLGKLYSFSE
QQLVDCDASDNGCEGGHPSNSLKFIQENNGLGLESDYPYKAVAGTCKKVKNVATVTGSRRVTDGSETGLQ
TIIAENGPVAVGMDASRPSFQLYKKGTIYSDTKCRSRMMNHCVTAVGYGSNSNGKYWIIRNSWGTSWGDA
GYFLLARDSNNMCGIGRDSNYPTGVKLI

Molecule Role : Protective antigen
Molecule Role Annotation : (He, 2012)

4. Gal/GalNAc lectin

Gene Name : Gal/GalNAc lectin
Sequence Strain (Species/Organism) : Entamoeba histolytica HM-1:IMSS
VO ID : VO_0011323
NCBI Gene ID : 3404842
NCBI Protein GI : 67469085
Locus Tag : EHI_046650
Genbank Accession : DS571321
Protein Accession : XP_650534
Taxonomy ID : 294381
Chromosome No : Unknown
Gene Starting Position : 16307
Gene Ending Position : 19930
Gene Strand (Orientation) : -
Protein pI : 4.63
Protein Weight : 126939.55
Protein Length : 1207
Protein Note : transcript EHI_046650A

DNA Sequence : Show Sequence

>NW_001915036.1:16307-19930 Entamoeba histolytica HM-1:IMSS scf_1104750517013 genomic scaffold, whole genome shotgun sequence
ATTATCCATTGAAATTAGCATTTGTGGCATTATCATCTTTAGCTGTGAATTGTGGGTTATTCACAGTATT
ATCAACAGTATTCTTTCTTGCAGAAATAACAATATCAACAGTTTGCTTAATTCCAATAGCAATAATTACC
ATAACAACAACAATTACTGCAACAACAACTGCAACAGTGGTACCAGCAGCAATAGCAGCTGTATTATCAA
CGTCTTGCCATAACAAACAAACAGCATCTTTATCAACCAATTCATCATTGATCTTACAATTACCACATGC
ATCTAATGAGAATCTATGATCTGCATAATCAGAGTACATTGTTAAAATCCACCCACTTTCAGATTGTAAT
GAACATTCACAATAGAAACAATTCTTAGCTGCTTTAGACATATTAGGGAATTGAATATCAATATCACATT
GAACAAAATTAGTTTCAATTTCTCCTGTTTCTTTGTCACAATAAGCGTCTTGACATTTATTCTTATAGAG
CAATGCTTTTTCATGTCCATCAATATTACTTGTCCATTTATGTGTTATCACTCCTTCAGTGATAGTTTCA
ACACAGGTATAATTATAACATTTATCAGTACAATCCCTATCATTAGATGGCTCATCACTACATTTTGTAA
ATTCCTTCTTGATACAATATCCTGTACTTGTATCACATTTACCTGTTAATGAAGCACACCCAACATCAGC
AGTATTTGATGAACAAATAGAATCATCATACACACCACTACATTTTGGAATACTTCCAGAAGCATCACAA
TTAGTTTTCATACAAATAACTTCTCCAGGTTTACTAGGAGGAAGTGATGGACAAATAGTGACATTAGTTG
GTTCACAAAGTTGGGATGTTCCAGTCTTTACTTGAATGAAACAATTATTAGTTGGATTACAATCTCCTTC
ATATTTACAATCCCCATCTGAACAAGTCATCTGATAAATATTTCCAGATGCATCTACTTGATTTGGACAT
TTATCAACAAGAGTAGACTCTTTATCCATTCCACTACAATACTTACATAAACTTTTTACCTTTTCTTCGT
TTGAATTCCATTCACATTTATATTCATCAAATGTTGTGCCAATAATTAATTTGTAATCAAGAACATCAAG
ACATTTACTAGGGAAATTCTCATGTTTAGTACAATCAAATTCATCATCAATATGACAACTTCCATCACGA
CATACATATGGAATACCATTTATATTCTTTTTATTAGTACAATCCATTTTAATAAGTTTAGCTGGGTCAA
CAAGAATATTATCATATGAACAATACATACACTGACTATCTAAAATAACTTTTGATCCATCTTTTACAAT
AACTTTACATTCTCCATTTGCATATTCCCATTCATAATATTGTTCACAATCACTTAATCTATCTTTGAAA
AGATCTTTACAATCATATTCATCTGGTGCTTGACATTCTCCATCTTTACAAACAAATGGAATTCCTTGTG
ATGTAGTCAAACCTTCACATTTATTAACAATTTCATTTCCATCACAAATTTTACATTCTTGAATTGCTTT
ATCTGTAGTTACAAGTATACATTCTCTATTTCCACTACATACATAATTAGCATATCCATCACATTTTTCA
GGTACTTTTTCTTTACATACATATTCCTCTTGGTCTACAACATATTGAGTCGTTCCATTAGCAGTATATT
CTTTACAGACTTTTTTGTAACAACCTTCCCAAACAATATCATGTCCTTTAAGCTCTTCACAATTATCAAC
ATTAATACATTTTGGATCCCCATCTGTATAATCACAAACTTCGCCATTAGTACATCCATTACTAGTATCA
CATTTACATTGATATGATGTAGATGCATCACATCGACAATTTCCATTAACTTTCCCACACACTTTCATTC
CAGAACTACATCCAACTAAATTCATAACACAATTTCCAGTTTCACTATCACATGTAGCTTCATAACATGG
ATTTTCTTCATATGGAGATACTTTAATACATTTCTTTTCTTGAACCATACATGTTCCAGCAGAACAATAA
TATTCTTCACACTTACTTGATAATTTAGGACAATAGCTAGATGATTGTAATGTATTTGGAATACATTCTC
CATTTGTTCTATCACATGAATAAGTTCTACAAACAAATTTTTCTACTCCAGATTCAATAATTGAAGATGG
CTTAATATCATCAGTACAATTACTTCTAAAAGCACAGTTGTTTCCTGAACAATAAGGCTCTAAACATTTA
ACTGTTGAAACACATTTATTTTGTTCAATAGTACATCCAATATCTTCAACACATTTAGCTACACCTAAAC
AACTTTCTGTTGTACATTTTCTTTTTTCAATTTTATGATCAGCACTTGGATAATAAACACATTCTCCATT
TTCAGTATTACATGTTGTATAATAACATTCACTATGACAACACATTGGACATGTACAACGAGCCCCACCA
TCACAAAATCCTTTACAAGTTTTTCTATCACATAATTCAGTATTATTTGCCATAATAGTATTATATAATT
GTGGAAGAGAAGTGCTTAATGATGAAACAGATGATTTAAAGTAATGTTCCCCTTTATTAACTAATTCTTC
AAGTTGATATTCTTCTTCAATTGATGAGTCTAAATTAAATACATAAAATGTAGTATTATGACTATAAAGA
GTATTTAACATATTAGAAGCTTTTCCTGCATATTTACTGATATAAACAATATTCTTTCCTGCTTTTGAAG
ACATTTGGTTATATACAGTTTCTATAGCTTTTGTTTCATTTCCTTTTCTCATAACAGTAATTCCATTTAA
TACATTTTTAATATTATCCTTTGTTACTAATGAATCTGAATGATATGGATTTTGAGAGTTAATATAATAA
GCGAATGAAGTATCATTTGGGAATAAATCAATCAAATAATTAACAATTGAACTAAATATATTTCTTAATG
TATTAGTCATATCTAAATTAACAACAATACCAACCGCCATATTATTTGTTGGTGGTAAAACAGTAGAAGC
ATGACATTTAGTAATATTATTATTTTTATAGTCAGTGATAAAATTATCAGAAAATTCTGAACTACTTCTA
AATGTAATAACTTTACCTCCAATATATTCAAATCTACATGGTGACATTCCTTCTGCATATTTATTTGTTA
CATCATATGTTTTTTCAAGAAAATATGCAGCTGTTAATGGTGGTTTAGCAGCATATTTATAACAAGTTAA
TCCATTAATTGAAACAACTGGTAATTTAGAAGTATCTGATGGAATACGAGACCAATCCAATTGATATTCT
CTAATAGGATATCCCATTTTCTTTCTACACATATTTTCTTCTTTTGTATCACTTTTATCACGGTCATAAT
CTTGATTAAATATCATTTCAGTAAAATATTTACTTTGGTCTTTAGTAGGAAAATTACTATCAATAGTTGT
CCATTCTAAATTTCTCCATGGTTGCATTGTTAAATAATAAAATACACTATACTTTTTATTTACACTTCTT
GACCATGAAGCTGCATTTTTACCCATTCCCATTCTTCCTTTATCTTGGATATCTACAGTTCCAGAAAACT
CATTTAAATTAATTCCTAAAGCAATTGAAGCATAAAATAATACCAAAATTATCA

Protein Sequence : Show Sequence

>XP_650534.1 Gal/GalNAc lectin heavy subunit, putative [Entamoeba histolytica HM-1:IMSS]
MIILVLFYASIALGINLNEFSGTVDIQDKGRMGMGKNAASWSRSVNKKYSVFYYLTMQPWRNLEWTTIDS
NFPTKDQSKYFTEMIFNQDYDRDKSDTKEENMCRKKMGYPIREYQLDWSRIPSDTSKLPVVSINGLTCYK
YAAKPPLTAAYFLEKTYDVTNKYAEGMSPCRFEYIGGKVITFRSSSEFSDNFITDYKNNNITKCHASTVL
PPTNNMAVGIVVNLDMTNTLRNIFSSIVNYLIDLFPNDTSFAYYINSQNPYHSDSLVTKDNIKNVLNGIT
VMRKGNETKAIETVYNQMSSKAGKNIVYISKYAGKASNMLNTLYSHNTTFYVFNLDSSIEEEYQLEELVN
KGEHYFKSSVSSLSTSLPQLYNTIMANNTELCDRKTCKGFCDGGARCTCPMCCHSECYYTTCNTENGECV
YYPSADHKIEKRKCTTESCLGVAKCVEDIGCTIEQNKCVSTVKCLEPYCSGNNCAFRSNCTDDIKPSSII
ESGVEKFVCRTYSCDRTNGECIPNTLQSSSYCPKLSSKCEEYYCSAGTCMVQEKKCIKVSPYEENPCYEA
TCDSETGNCVMNLVGCSSGMKVCGKVNGNCRCDASTSYQCKCDTSNGCTNGEVCDYTDGDPKCINVDNCE
ELKGHDIVWEGCYKKVCKEYTANGTTQYVVDQEEYVCKEKVPEKCDGYANYVCSGNRECILVTTDKAIQE
CKICDGNEIVNKCEGLTTSQGIPFVCKDGECQAPDEYDCKDLFKDRLSDCEQYYEWEYANGECKVIVKDG
SKVILDSQCMYCSYDNILVDPAKLIKMDCTNKKNINGIPYVCRDGSCHIDDEFDCTKHENFPSKCLDVLD
YKLIIGTTFDEYKCEWNSNEEKVKSLCKYCSGMDKESTLVDKCPNQVDASGNIYQMTCSDGDCKYEGDCN
PTNNCFIQVKTGTSQLCEPTNVTICPSLPPSKPGEVICMKTNCDASGSIPKCSGVYDDSICSSNTADVGC
ASLTGKCDTSTGYCIKKEFTKCSDEPSNDRDCTDKCYNYTCVETITEGVITHKWTSNIDGHEKALLYKNK
CQDAYCDKETGEIETNFVQCDIDIQFPNMSKAAKNCFYCECSLQSESGWILTMYSDYADHRFSLDACGNC
KINDELVDKDAVCLLWQDVDNTAAIAAGTTVAVVVAVIVVVMVIIAIGIKQTVDIVISARKNTVDNTVNN
PQFTAKDDNATNANFNG

Molecule Role : Protective antigen
Molecule Role Annotation : Study tested if vaccination with the E. histolytica Gal/GalNAc lectin could prevent cecal infection in a C3H mouse model of amebic colitis. Vaccination prevented intestinal infection with efficacies of 84 and 100% in the two native lectin trials and 91 and 34% in the two LecA trials. Results show for the first time that immunization with the Gal/GalNAc lectin can prevent intestinal amebiasis in mice (Houpt et al., 2004).
Related Vaccine(s): E. histolytica Gal/GalNAc lectin protein vaccine

5. gEh29

Gene Name : gEh29
Sequence Strain (Species/Organism) : Entamoeba histolytica
VO ID : VO_0011322
NCBI Nucleotide GI : 399673
NCBI Protein GI : 399674
Protein Accession : CAA50324.1
Other Database IDs : CDD:223527
CDD:239313
GOA:P19476
InterPro: IPR000866
InterPro: IPR012335
InterPro: IPR012336
InterPro: IPR017936
InterPro: IPR019479
UniProtKB/UniProt: P19476
Taxonomy ID : 5759
Gene Strand (Orientation) : ?
Protein Name : alkyl hydroperoxide reductase
Protein pI : 7.38
Protein Weight : 25237.95
Protein Length : 304
Protein Note : Alkyl hydroperoxide reductase subunit AhpC (peroxiredoxin) [Defense mechanisms]; COG0450

DNA Sequence : Show Sequence

>gi|399673|emb|X70996.1| E.histolytica gEh29 gene for alkyl-hydroperoxidase reductase
TTAGTTAAAAAGTATTTGATGACTTATTAGTTCATGTTACATATACAAAAATAATACTTTTATTGAAGTT
TTGTGCCAATACATTTCTCTTTCTCCTCATCATATTCTTCATTAGATTCTTTGAGAATGTGTGGATGTGT
GTATCTCCGTTTTCTTCTTTTTATCTAGTCATTTTTGTTTTCTATTTACCAGTTCTTTCATTATAAGTTG
TTTAAATGTTGAATAATTACCATAATGAGAATAATGCAGAAGTGATGATGACGACATTTTTATTTTAGTT
AAGTAAAGATGATTTTGGTAGTTCATTTGTCATTTAAACATCTCATCATCACCACAATCTCATCAATTCA
ATCAGTCAAATGTCTTGCAATCAACAAAAAGAGTGTTGTAAAAAAGAATGTCAAGAGAAAGAATGTTGTA
AAGAATGTTGTTGTCCAAGAATAAAAGCATTTAAGAAATTTATAAACACATTTGAAAAAGCACAAATTGG
AAAAGAAGCACCAGAATTTAAAGCACCAGCATATTGTCCATGTGGTTCAATCAAAGAGATTGATATTAAT
GAATATAGAGGAAAATATGTTGTATTGTTGTTTTATCCATTGGATTGGACATTTGTTTGTCCAACAGAAA
TGATTGGATATAGTGAACTTGCAGGACAATTGAAAGAAATCAATTGTGAAGTTATTGGAGTGAGTGTAGA
TTCAGTTTATTGTCATCAAGCATGGTGTGAAGCAGATAAAAGTAAAGGAGGAGTAGGAAAGTTGACATTC
CCATTAGTATCAGATATTAAGAGATGCATTTCTATCAAATATGGAATGTTAAATGTCGAAGCAGGAATTG
CAAGAAGAGGATATGTCATCATTGACGATAAAGGAAAAGTAAGATACATTCAAATGAATGATGATGGAAT
TGGAAGATCAACGGAAGAAACAATCAGAATAGTGAAAGCAATTCAATTCAGTGATGAACATGGAGCAGTT
TGTCCACTCAATTGGAAACCAGGCAAAGACACCATTGAACCAACACCAGATGGAATTAAGAAATATTTAA
CAGCACATTAAAACAAACAAGATAATTTAATACAAATTATTTTATGTTTTATAAGAAGAAAATGATATAA
TAAAAGATAAA

Protein Sequence : Show Sequence

>CAA50324.1 alkyl hydroperoxide reductase [Entamoeba histolytica]
MSCNQQKECCKKECQEKECCKECCCPRIKAFKKFINTFEKAQIGKEAPEFKAPAYCPCGSIKEIDINEYR
GKYVVLLFYPLDWTFVCPTEMIGYSELAGQLKEINCEVIGVSVDSVYCHQAWCEADKSKGGVGKLTFPLV
SDIKRCISIKYGMLNVEAGIARRGYVIIDDKGKVRYIQMNDDGIGRSTEETIRIVKAIQFSDEHGAVCPL
NWKPGKDTIEPTPDGIKKYLTAH

Molecule Role : Protective antigen
Molecule Role Annotation : 80% of C3H/HeJ mice immunized with Eh29 administered in combination with a subclinical dose of whole cholera toxin, but not as an Eh29-CTxB fusion, showed no evidence of infection in tissue sections harvested following intracecal challenge with virulent E. histolytica trophozoites. These results suggest that Eh29 is capable of inducing protective anti-amoebic immune responses in mice following oral immunization and could be used in the development of oral vaccines against amoebiasis (Carrero et al., 2010).
Related Vaccine(s): E. histolytica Eh29 protein vaccine

6. SREHP

Gene Name : SREHP
Sequence Strain (Species/Organism) : Entamoeba histolytica HM-1:IMSS
VO ID : VO_0011324
NCBI Gene ID : 3402462
NCBI Protein GI : 67463194
Locus Tag : EHI_116360
Genbank Accession : DS571976
Protein Accession : XP_648254
Taxonomy ID : 294381
Chromosome No : Unknown
Gene Starting Position : 1107
Gene Ending Position : 1833
Gene Strand (Orientation) : -
Protein pI : 4.01
Protein Weight : 24419.56
Protein Length : 233
Protein Note : transcript EHI_116360A

DNA Sequence : Show Sequence

>NW_001915691.1:1107-1833 Entamoeba histolytica HM-1:IMSS scf_1104750518053 genomic scaffold, whole genome shotgun sequence
AGACTAAAGTCAAATAACTTCATTTAGAAGATGATAGCTATAATGATAGCACAGAAAACAATGAATGGAC
TTGATGCAGCATCAAGGTTATTATTATCGTTATCTGAACTACTTCCTGATTTATCATTTGAATTACTAGT
TGAGCTTGCTTCTGGTTTATTAGTTGAGCTTGCTTCTGGTTTATTAGTTGAGCTTGCTTCTGGTTTATTA
GTTGAGCTTGCTTCTGGTTTATTAGTTGAGCTTGCTTCTGGTTTATTATCTGGTTTATCACTTGAGCTTG
CTTCTGGTTTATTATCTGGTTTATCACTTGAGCTTGCTTCTGGTTTATTATCTGGTTTATCACTTGAACT
TGCTTCTGGTTTATTATCTGGTTTATCACTTGAACTTGCTTCTGGTTTATTATCTGGTTTATCACTTGAA
CTTGCTTCTGGTTTATCACTTGAACTTGCTTCTGGTTTATTATCTGGTTTATCACTTGAGCTTGATTCTG
AGTTATCACTTGAACTTGCTTTTTCATCTTCATCATCTTCATTATCTTCATTTGAACTTGATTCTGGTTT
TGCTGAGCTACTTTTTTCTTTTTCTTCAGCTTCTTCAAGCTTTTCAGGACTAGCTTCGTTCTTTAAAAAT
ACACCGTAGATATTAGTATCTTTTACTTCTTGATCCAAATCAAGAATGATATTAGTTGCACTAGTGAATG
CAATAAACAATAAAAATGCGAACATTG

Protein Sequence : Show Sequence

>XP_648254.1 serine-rich protein [Entamoeba histolytica HM-1:IMSS]
MFAFLLFIAFTSATNIILDLDQEVKDTNIYGVFLKNEASPEKLEEAEEKEKSSSAKPESSSNEDNEDDED
EKASSSDNSESSSSDKPDNKPEASSSDKPEASSSDKPDNKPEASSSDKPDNKPEASSSDKPDNKPEASSS
DKPDNKPEASSSDKPDNKPEASSTNKPEASSTNKPEASSTNKPEASSTNKPEASSTSNSNDKSGSSSDND
NNNLDAASSPFIVFCAIIIAIIF

Molecule Role : Protective antigen
Molecule Role Annotation : Report describes a recombinant fusion protein containing the serine-rich Entamoeba histolytica protein (SREHP), a protective antigen derived from virulent amebae, and a bacterially derived maltose-binding protein (MBP) from an attenuated strain of Salmonella typhimurium. Gerbils vaccinated with S typhimurium SREHP-MBP were protected against amebic liver abscess after challenge with E. histolytica, the most common extraintestinal complication of amebiasis (Zhang and Stanley, 1996).
Related Vaccine(s): E. histolytica SREHP protein vaccine

III. Vaccine Information

1. E. histolytica CEL-170/4 protein vaccine

a. Vaccine Ontology ID:

VO_0011414

b. Type:

Subunit vaccine

c. Status:

Research

d. Antigen

E. histolytica alactose-specific adherence lectin heavy subunit (CEL-170/4)

e. Gene Engineering of CEL-170/4

Type: Recombinant protein preparation
Description: The galactose-specific lectin has been purified from a pathogenic strain of E. histolytica by monoclonal antibody affinity chromatography (Petri and Ravdin, 1991).
Detailed Gene Information: Click here.

f. Adjuvant:

VO ID: VO_0000139

g. Adjuvant:

VO ID: VO_0000142

h. Immunization Route

Intraperitoneal injection (i.p.)

i. Mongolian Gerbil Response

Vaccination Protocol: Adult male gerbils were immunized by intraperitoneal or subcutaneous injection of 10 ,ug of the affinity-purified lectin emulsified in complete Freund's adjuvant (GIBCO, Grand Island, N.Y.) and boosted with 10 ,ug of the lectin in incomplete Freund's adjuvant at 2 and 4 weeks. Control gerbils were sham immunized with Freund's complete and incomplete adjuvants alone. Prechallenge gerbil sera were collected at 5 weeks after the initial immunization by cardiac puncture (Petri and Ravdin, 1991).
Challenge Protocol: Gerbils were challenged intrahepatically with E. histolytica (Petri and Ravdin, 1991).
Efficacy: Researcherse tested the ability of the galactose-specific adherence lectin of E. histolytica to elicit a protective immune response in conjunction with Freund's incomplete and complete adjuvants. Four independent trials demonstrated complete protection from amebic liver abscess formation in 67% of lectin-immunized gerbils. The gerbil antilectin antibodies were shown by Western immunoblotting to be directed to the heavy subunit (CEL-170/4) but not the light subunit of the lectin (Petri and Ravdin, 1991).

2. E. histolytica Eh29 protein vaccine

a. Vaccine Ontology ID:

VO_0011450

b. Type:

Subunit vaccine

c. Status:

Research

d. Antigen

E. histolytica alkyl hydroperoxide reductase Eh29

e. Gene Engineering of gEh29

Type: Recombinant protein preparation
Description: The full coding region of the gEh29 gene which encodes Eh29 (GenBank Accession No. X70996.1) was amplified by PCR and the 0.7 Kb amplicon was cloned into the expression vector pRSET-A (Invitrogen, CA, USA) following standard methods. After transformation into Escherichia coli BL21 (DE3) pLysS (Stratagene, CA, USA) positive clones were selected on ampicillin and chloramphenicol and were induced for expression of amino-terminal His-tagged Eh29 by incubation with 2 mM IPTG (Carrero et al., 2010).
Detailed Gene Information: Click here.

f. Adjuvant:

VO ID: VO_0000142

g. Immunization Route

Intraperitoneal injection (i.p.)

h. Mouse Response

Host Strain: C3H/HeJ
Vaccination Protocol: Mice were divided into seven groups of 10 animals. Two groups were left unimmunized. The remaining five groups were immunized using Eh29 combined with CT (Eh29 + CT), Eh29–CTxB fusion protein, CT alone, CTxB alone, or ARF combined with CT (ARF + CT). Mice were immunized orally with a dose of the relevant protein solution on days 1, 7, and 21 using a plastic cannula (standard wall spaghetti tubing; Chemplast Inc., USA). The protein solutions were prepared in 0.2 M NaHCO3, pH 8.3 such that one dose contained 100 μg of either recombinant Eh29, Eh29–CTxB or ARF, and 10 μg of commercial CT or CTxB, as pertinent. Additionally, on day 14, all immunized groups received an intraperitoneal boost with 25 μg of the corresponding recombinant protein emulsified in incomplete Freund’s adjuvant. The groups receiving only CT or CTxB were boosted with adjuvant emulsified in PBS (Carrero et al., 2010).
Challenge Protocol: On day 27 all mice (except those from one of the unimmunized groups) were infected intracecally with E. histolytica trophozoites recovered after three passages from hamster liver abscesses (Carrero et al., 2010).
Efficacy: 80% of C3H/HeJ mice immunized with Eh29 administered in combination with a subclinical dose of whole cholera toxin, but not as an Eh29-CTxB fusion, showed no evidence of infection in tissue sections harvested following intracecal challenge with virulent E. histolytica trophozoites. These results suggest that Eh29 is capable of inducing protective anti-amoebic immune responses in mice following oral immunization and could be used in the development of oral vaccines against amoebiasis (Carrero et al., 2010).

3. E. histolytica Gal/GalNAc lectin protein vaccine

a. Vaccine Ontology ID:

VO_0011451

b. Type:

Subunit vaccine

c. Status:

Research

d. Antigen

E. histolyica Gal/GalNAc lectin

e. Gene Engineering of Gal/GalNAc lectin

Type: Recombinant protein preparation
Description: The native E. histolytica Gal/GalNAc lectin was purified from strain HM1:IMSS trophozoites grown under axenic conditions as described previously [5]. A large fragment of the Gal/GalNAc lectin heavy subunit spanning amino acids 578–1154 (“LecA”) was cloned into a pRSET-A vector (Invitrogen, Carlsbad, CA) with a kanamycin resistance gene and expressed in E. coli. The E. coli cells were lyzed by sonication and isolated inclusion bodies were denatured in inclusion body solubilization reagent (Pierce, Rockford, IL) (Houpt et al., 2004).
Detailed Gene Information: Click here.

f. Adjuvant:

VO ID: VO_0000139

g. Adjuvant:

VO ID: VO_0000142

h. Immunization Route

Intraperitoneal injection (i.p.)

i. Mouse Response

Host Strain: C3H/HeJ
Vaccination Protocol: Mice were immunized with a combined intranasal and intraperitoneal regimen over 6–9 weeks. Intranasal immunizations used 10 μg of antigen and 1 μg of cholera toxin (Sigma) administered intranasally in 20 μl of PBS into C3H mice under isoflurane anesthesia. Intraperitoneal immunizations used 15 μg of antigen emulsified in equal volumes of either complete (CFA) or incomplete Freund’s adjuvant (IFA) (Gibco, Grand Island, NY) injected via 20 gauge syringe. The lectin-1 trial utilized 150 μl of complete Freund’s adjuvant, the week 4 immunization of the lectin-2 trial two utilized 100 μl of CFA, and all other i.p. immunizations utilized 150 μl of incomplete Freund’s adjuvant. Sham-immunized mice from each trial were administered an identical regimen of PBS with adjuvant (Houpt et al., 2004).
Challenge Protocol: Mice were challenged intracecally with trophozoites 2 weeks after the final immunization (Houpt et al., 2004).
Efficacy: Vaccination prevented intestinal infection with efficacies of 84 and 100% in the two native lectin trials and 91 and 34% in the two LecA trials. Results show for the first time that immunization with the Gal/GalNAc lectin can prevent intestinal amebiasis in mice (Houpt et al., 2004).

4. E. histolytica SREHP protein vaccine

a. Vaccine Ontology ID:

VO_0011416

b. Type:

Subunit vaccine

c. Status:

Research

d. Antigen

E. histolytica serine-rich protein (SREHP)

e. Gene Engineering of SREHP

Type: Recombinant protein preparation
Description: Expressed the SREHP-MBP molecule in an attenuated vaccine strain of Salmonella typhimurium (Zhang and Stanley, 1996).
Detailed Gene Information: Click here.

f. Immunization Route

Oral

g. Gerbil Response

Vaccination Protocol: female BALB/c mice or gerbils were deprived of water and food for 4 h and then were given 50 ml of 10% sodium bicarbonate solution per orogastric gavage with a 21-gauge ball-tipped gavage needle. Five minutes later, they received by gavage 50 ml of 0.16Mphosphate-buffered saline (PBS), pH 7.0, containing 109 S. typhimurium cells harboring either pSS3137 (Stm-SREHP) or pYA3137 (Stm-Ctrl). Mice and gerbils were immunized on days 0, 7, and 21. Serum samples were obtained on days 0, 7, 21, and 28 (Zhang and Stanley, 1996).
Challenge Protocol: On day 35 (14 days following the final booster immunization) control gerbils vaccinated with Stm-Ctrl and gerbils vaccinated with Stm-SREHP were challenged intrahepatically with 5 x 10^5 E. histolytica HM1:IMSS trophozoites (Zhang and Stanley, 1996).
Efficacy: Report describes a recombinant fusion protein containing the serine-rich Entamoeba histolytica protein (SREHP), a protective antigen derived from virulent amebae, and a bacterially derived maltose-binding protein (MBP) from an attenuated strain of Salmonella typhimurium. Gerbils vaccinated with S typhimurium SREHP-MBP were protected against amebic liver abscess after challenge with E. histolytica, the most common extraintestinal complication of amebiasis (Zhang and Stanley, 1996).

IV. References

1. Carrero et al., 2010: Carrero JC, Contreras-Rojas A, Sánchez-Hernández B, Petrosyan P, Bobes RJ, Ortiz-Ortiz L, Laclette JP. Protection against murine intestinal amoebiasis induced by oral immunization with the 29kDa antigen of Entamoeba histolytica and cholera toxin. Experimental parasitology. 2010; ; . [PubMed: 20303954].

2. He, 2012: He GZ. Entamoeba histolytica: cloning, expression and evaluation of the efficacy of a recombinant amebiasis cysteine proteinase gene (ACP1) antigen in minipig. Experimental parasitology. 2012; 130(2); 126-129. [PubMed: 22154977].

3. Houpt et al., 2004: Houpt E, Barroso L, Lockhart L, Wright R, Cramer C, Lyerly D, Petri WA. Prevention of intestinal amebiasis by vaccination with the Entamoeba histolytica Gal/GalNac lectin. Vaccine. 2004; 22(5-6); 611-617. [PubMed: 14741152].

4. Petri and Ravdin, 1991: Petri WA Jr, Ravdin JI. Protection of gerbils from amebic liver abscess by immunization with the galactose-specific adherence lectin of Entamoeba histolytica. Infection and immunity. 1991; 59(1); 97-9101. [PubMed: 1987067].

5. Priest et al., 2010: Priest JW, Kwon JP, Montgomery JM, Bern C, Moss DM, Freeman AR, Jones CC, Arrowood MJ, Won KY, Lammie PJ, Gilman RH, Mead JR. Cloning and characterization of the acidic ribosomal protein P2 of Cryptosporidium parvum, a new 17-kilodalton antigen. Clinical and vaccine immunology : CVI. 2010; 17(6); 954-965. [PubMed: 20410328].

6. Wiki: Entamoeba histolytica: Entamoeba histolytica [http://en.wikipedia.org/wiki/Entamoeba_histolytica]

7. Zhang and Stanley, 1996: Zhang T, Stanley SL Jr. Oral immunization with an attenuated vaccine strain of Salmonella typhimurium expressing the serine-rich Entamoeba histolytica protein induces an antiamebic immune response and protects gerbils from amebic liver abscess. Infection and immunity. 1996; 64(5); 1526-1531. [PubMed: 8613356].