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Immunity relatively inefficient
Helminths are much adapted
Most helminths extracellular & too large for phagocytosis
Growth is not exponential
Usually mild infections
No division inside host
Do not pose imminent threat
Over-dispersion.
Immunity relatively inefficient
Helminths are much adapted
Most helminths extracellular & too large for phagocytosis
Growth is not exponential
Usually mild infections
No division inside host
Do not pose imminent threat
Over-dispersion.
1.Host:AGE
SEX
Genetic makeup –HbA to HbB : More superior in resistance to H.contortus and O.ostertagii
Enhanced resistance to Cooperia oncophora in Zebu as compared to European cattle
Fasciola gigantica resistance in Indonesian thin tailed sheep (Hansen et al,1999)
Greater production of Th2-like cytokines (IL-4, IL-5, IL-13) in resistant breeds to Haemonchus contortus (Sallé et al 2014)
2.Parasite: Presence of adult worm delays larval development if a new infection takes place
as in E. granulosus in sheep and T saginata in cattle
Interspecific competition between helminths for nutrient and habitat
Humoral:Usually IgE mediated
Cell mediated Immunity can be transferred to naïve animals by transfer of lymphoid
cells of infected animals and infected animals show DTH in Trichinella spiralis (Wakelin, 1978)
Immunity can be transferred to naïve animals by both lymphocytes and serum in Trichostrongylus colubriformes
(J. K. Dineen and B. M. Wagland …1996)
Immunity can be transferred to syngenic sheep by transfer of lymphocytes in Haemonchus contortus. (Smith WD et al 1984)
*Dominance of Th1 or Th2 depends on :
Antigen presenting cell type
Co-stimulatory molecules
Cytokines
Nature and dose of parasite antigen
*Dominance of Th1 or Th2 depends on :
Antigen presenting cell type
Co-stimulatory molecules
Cytokines
Nature and dose of parasite antigen
Type 1 immunity
Usually found in early stages of helminth infection and larval migration.
Few examples are:Dead cysts of Taenia solium (E. Sciutto et al, 2000)
Peri-oval granuloma formation in Schistosoma mansoni (E. J. Pearce et
al….1991)
Th1-like responses might act on migrating larvae of Fasciola spp through the liver parenchyma (E Moreau et al …..2010)
Usually found in early stages of helminth infection and larval migration.
Few examples are:Dead cysts of Taenia solium (E. Sciutto et al, 2000)
Peri-oval granuloma formation in Schistosoma mansoni (E. J. Pearce et
al….1991)
Th1-like responses might act on migrating larvae of Fasciola spp through the liver parenchyma (E Moreau et al …..2010)
Journal of NeuroimmunologyVolume 127, Issues 1–2, June 2002
The Journal of Experimental Medicine " Volume 173 January 1991
Journal of Biomedicine and Biotechnology (2010)
Highly complex multicellular, multifactorial system
Refers to combined immune response, which includes both innate and adaptive components.
Regulated by Th2 cells
Cytokines IL-4,IL-5,IL-9,IL-13.
Characterized by:
Highly complex multicellular, multifactorial system
Refers to combined immune response, which includes both innate and adaptive components.
Regulated by Th2 cells
Cytokines IL-4,IL-5,IL-9,IL-13.
Characterized by:
B cell proliferationAntibody productionClass switchingEosinophilia and Mastocytosis
IL-33
TSLP
IL-25
Source: Secreted by epithelial cells and other cell types (Th2
and mast cells) Functions:
IL-25 induces the production of other cytokines, including IL-4, IL-5 and IL-13 in multiple tissues, which stimulate the expansion of Eosinophils
All three alarmins promote Th2 responses through their ability to induce Th2 cytokine production from ILC2s. (Natural helper cells, Nuocytes )
ILC2s like Th2 cells can produce IL-5, IL-9 and IL-13.
. Nat Rev Immunol 2011;11:375–88.
.
Source: Th2 cells
Mast cells
Eosinophils
NK cells
Functions: Key role in the differentiation, maturation, and survival of eosinophils derived from bone marrow precursors.
IL-5 has been shown to act on mast cell and basophil to release vasoactive mediators
Source: Th2 cells
Mast cells
Eosinophils
NK cells
Functions: Key role in the differentiation, maturation, and survival of eosinophils derived from bone marrow precursors.
IL-5 has been shown to act on mast cell and basophil to release vasoactive mediators
The Journal of ImmunologyMarch 15, 2011
*Sources:*Primarily produced by Monocytes
*To a lesser extent by:
Type 2 T helper cells (TH2),
Mast cells
Treg cells
*Sources:*Primarily produced by Monocytes
*To a lesser extent by:
Type 2 T helper cells (TH2),
Mast cells
Treg cells
Specifically defined macrophages that respond to signalling through the IL-4R alpha.
Have Receptors for both IL-4 and IL-13 and their receptors share the common IL-4R chain, which is central to most type 2 effector responses
IL-4 strongly induces a non-inflammatory response from AAM..
Specifically defined macrophages that respond to signalling through the IL-4R alpha.
Have Receptors for both IL-4 and IL-13 and their receptors share the common IL-4R chain, which is central to most type 2 effector responses
IL-4 strongly induces a non-inflammatory response from AAM..
Arginase .Arginase suppresses the NO mediated anti-microbial pathways of classically activated macrophages.
RELM-α ::Stimulation of collagen production in myofibroblasts (providing a potential link between alternatively activated macrophages, fibrosis, and tissue repair
RELM β : Intestinal goblet cells up regulate and secrete RELM-β under the control of IL-13 signalling through the IL-4 receptor.
Arginase .Arginase suppresses the NO mediated anti-microbial pathways of classically activated macrophages.
RELM-α ::Stimulation of collagen production in myofibroblasts (providing a potential link between alternatively activated macrophages, fibrosis, and tissue repair
RELM β : Intestinal goblet cells up regulate and secrete RELM-β under the control of IL-13 signalling through the IL-4 receptor.
.
*The factors involved in the activation of eosinophils
*Granulocyte-macrophage colony-stimulating factor (GM-CSF)
*EAF ; Eosinophil Activating Factor
*PAF ; Platelet-Activation Factor
Text book of veterinary immunology 9th edition Ian R Tizzard
Cellular and Molecular Immunology 7th edition
.
Text book of veterinary immunology 9th edition Ian R Tizzard
EPO: oxidants and NOECP,ENT: Ribonucleases
Potent inflammatory cells that are distributed throughout mucosal barrier tissues
Mucosal mast cell proteinases are secreted in serum and local intestinal secretions during expulsion of GI nematodes
(Woodbury et al., 1984)
MCs play an important role as late-stage effectors
Mastocytosis controlled by IL3, IL9 and other stem cell factors
Potent inflammatory cells that are distributed throughout mucosal barrier tissues
Mucosal mast cell proteinases are secreted in serum and local intestinal secretions during expulsion of GI nematodes
(Woodbury et al., 1984)
MCs play an important role as late-stage effectors
Mastocytosis controlled by IL3, IL9 and other stem cell factors
.
Mast cells
Histamine 5HT Proteinases Prostaglandins Leucotrienes
Increased mucosal permeability/SM contraction
Immunity against helminths differs from bacterial and viral immunity
Helminths typically induce Type 2 immune response through the production of cytokines IL-4,IL-5,IL-9,IL-10, and IL-13.
Th1 responses are found only in early stages like larval migration.
Type 2 response is non inflammatory response.
Interleukins act on both innate effector cells and adaptive effector cells.
AAM plays main role in tissue repair through IL-4 and IL-13.
Eosinophils play role in parasite killing
Interleukins hence lead parasite killing, expulsion and tissue repair
Immunity against helminths differs from bacterial and viral immunity
Helminths typically induce Type 2 immune response through the production of cytokines IL-4,IL-5,IL-9,IL-10, and IL-13.
Th1 responses are found only in early stages like larval migration.
Type 2 response is non inflammatory response.
Interleukins act on both innate effector cells and adaptive effector cells.
AAM plays main role in tissue repair through IL-4 and IL-13.
Eosinophils play role in parasite killing
Interleukins hence lead parasite killing, expulsion and tissue repair
[1] Immunology of Parasitic Helminth Infections :Andrew S. MacDonald, MariaIlma Araujo, and Edward J. Pearce INFECTION AND IMMUNITY, Feb. 2002, p. 427–433[2] Protective immune mechanisms in helminth infection Robert M. Anthony, Laura I. Rutitzky, Joseph F. Urban Jr, Miguel J. Stadecker‡, and William C. Gause|| Eur J Immunol. 2003 Sep;33(9):2382-90[3] Anthony RM, Rutitzky LI, Urban JF, Stadecker MJ, Gause WC. Protective immune mechanisms in helminth infection. Nat Rev Immunol 2007;7:975–87. [4] Licona-Limón P, Kim LK, Palm NW, Flavell RA. TH2, allergy and group 2 innate lymphoid cells. Nat Immunol 2013;14:536–42.[5] Saenz SA, Taylor BC, Artis D. Welcome to the neighbourhood: epithelial cell derived cytokines license innate and adaptive immune responses at mucosal sites. Immunol Rev 2008;226:172–90.[6] Gause WC, Wynn TA, Allen JE. Type 2 immunity and wound healing: evolutionary refinement of adaptive immunity by helminths. Nat Rev Immunol 2013;13:607–14. (7) Allen JE, Maizels RM. Diversity and dialogue in immunity to helminths. Nat Rev Immunol 2011;11:375–88. (8) Tom N. McNeilly,and Alasdair J. Nisbet Immune modulation by helminth parasites of ruminants: implications for vaccine development and host immune competence Tom N. McNeilly, and Alasdair J. Nisbet Parasite 2014, 21, 51(9) Ian R Tizzard Textbook of veterinary immunology 9th edition
[1] Immunology of Parasitic Helminth Infections :Andrew S. MacDonald, MariaIlma Araujo, and Edward J. Pearce INFECTION AND IMMUNITY, Feb. 2002, p. 427–433[2] Protective immune mechanisms in helminth infection Robert M. Anthony, Laura I. Rutitzky, Joseph F. Urban Jr, Miguel J. Stadecker‡, and William C. Gause|| Eur J Immunol. 2003 Sep;33(9):2382-90[3] Anthony RM, Rutitzky LI, Urban JF, Stadecker MJ, Gause WC. Protective immune mechanisms in helminth infection. Nat Rev Immunol 2007;7:975–87. [4] Licona-Limón P, Kim LK, Palm NW, Flavell RA. TH2, allergy and group 2 innate lymphoid cells. Nat Immunol 2013;14:536–42.[5] Saenz SA, Taylor BC, Artis D. Welcome to the neighbourhood: epithelial cell derived cytokines license innate and adaptive immune responses at mucosal sites. Immunol Rev 2008;226:172–90.[6] Gause WC, Wynn TA, Allen JE. Type 2 immunity and wound healing: evolutionary refinement of adaptive immunity by helminths. Nat Rev Immunol 2013;13:607–14. (7) Allen JE, Maizels RM. Diversity and dialogue in immunity to helminths. Nat Rev Immunol 2011;11:375–88. (8) Tom N. McNeilly,and Alasdair J. Nisbet Immune modulation by helminth parasites of ruminants: implications for vaccine development and host immune competence Tom N. McNeilly, and Alasdair J. Nisbet Parasite 2014, 21, 51(9) Ian R Tizzard Textbook of veterinary immunology 9th edition