Review Article

Targeting TLR2 for Vaccine Development

Table 1

(a) TLR2 expression; (b) specificities reported for veterinary species.
(a)

Human and mouseReference

Antigen presenting cells: macrophages, monocytes, and DCs (CD8α +, CD8α , and plasmacytoid DCs in mouse; interstitial and Langerhans DCs but not plasmacytoid DCs in humans)[20]

Lymphocytes: B cells, CD4+, and CD8+ T cells, Treg cells, γ δ T cells, and NK cells
Granulocytes: neutrophils, basophils [21, 22]
Some epithelial cells

(b)

SpeciesCells and tissues reported to express TLR2MethodaInformation on the level of expressionReference

BovineMonocytesRT-PCR/FCStrong[23, 28]
Monocyte derived-macrophagesRT-PCR/FC
Alveolar macrophagesRT-PCR/FCIntermediate
Monocyte derived-DCsRT-PCR/FCWeak
CD172+ DCsRT-PCR/FC
CD172 DCsRT-PCR/FC
CD21+ B cellsRT-PCRNo signal[28]

OvineCD14+ monocytes from PBMCsFC[23]

Nilgai and BuffaloPBMCs, monocytes, DCs, testes, skin RT-PCRHigher in Nilgai than Buffalo [29]
BuffaloKidney, endometrium, bone marrow, tracheaRT-PCRHigher in endometrium and bone marrow

SwineMesenteric lymph nodes and Peyer's patchesRT-PCR, IHC, FCHigher than in spleen by RT-PCR [30]
Heart, thymus, lung, kidney, skeletal muscle, small intestineRT-PCRLower than in spleen
M cellsIHC, FC
T and B cellsFCHigher in T cells than in B cells
Monocytes, macrophage, and granulocytes, but not on peripheral blood lymphocytesFC [24]
Epithelial cells lining body entries (Lung, jejunum, kidney, liver)IHC
Alveolar MacrophagesWB[17]

EquinePBMCsRT-PCR[33]
Alveolar macrophagesRT-PCR[31]
Respiratory epithelial tissuesRT-PCR[32]

ChickenHeart, liver, gizzard, muscleRT-PCR, WBStrong[26]
Spleen, caecal tonsil, bursa, liverRT-PCRStrong[34]
Heterophils, monocytes, macrophages, B and T cells RT-PCR[34, 35]

CanineBlood mononuclear cells, lymph node, lung, liver, spleen, bladder, pancreas, small intestine, large intestine, and skinRT-PCR[18]
Blood neutrophils RT-PCR [27]
Blood neutrophils, monocytes FCHigher levels
LymphocytesFCLower levels

FelineSpleen, thymusRT-PCR [36]
CD4+ T cells, CD8+ T cells, CD21+ B cellsRT-PCRHigher in B cells than in T cells
BM-DCsRT-PCR[37]
Palatoglossal mucosaRT-PCR[38]

RT-PCR: reverse transcription-PCR; FC: flow cytometry; IHC: immunohistochemistry; WB: Western blot.