1.NLRP6 as a Negative Regulator of Innate Immunity.
Zahid MANZOOR ; Young Sang KOH
Journal of Bacteriology and Virology 2013;43(1):64-66
Nucleotide-binding and oligomerization domain (NOD)-like receptors (NLRs) play important role in immune responses by regulating nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kappaB), type I interferon and inflammasomes. Nod-like receptor pyrin domain-containing protein 6 (NLRP6) is vital for protection of mice from colitis and colorectal tumorigenesis. However, the role of NLRP6 in microbial infection remains unclear. NLRP6 was recently reported as negative regulator of inflammatory signaling and demonstrated that how it hinders clearance of bacterial pathogens.
Animals
;
B-Lymphocytes
;
Cell Transformation, Neoplastic
;
Colitis
;
Cytoskeletal Proteins
;
Immunity, Innate
;
Inflammasomes
;
Interferon Type I
;
Listeria monocytogenes
;
Mice
2.PKR as a Regulator of Inflammasome Activation.
Zahid MANZOOR ; Young Sang KOH
Journal of Bacteriology and Virology 2013;43(2):145-147
Detection of pathogen by pattern recognition receptors leads to activation of inflammasome which plays a crucial role in immune system. The inflammasome regulates the release of cytokines, such as interleukin (IL)-1beta, IL-18 and high-mobility group box 1 (HMGB1). Double-stranded RNA-dependent protein kinase (PKR) is a critical component of an inflammatory complex. Recently, the critical role of PKR was reported in regulation of multiple inflammasomes.
Cytokines
;
eIF-2 Kinase
;
Immune System
;
Inflammasomes
;
Interleukin-18
;
Interleukins
;
Receptors, Pattern Recognition
3.Caspase-11, the Main Executioner in Non-canonical Inflammasome.
Zahid MANZOOR ; Young Sang KOH
Journal of Bacteriology and Virology 2012;42(2):169-171
Murine caspase-11 is orthologus to human caspase-4 and caspase-5, and is required for the response to cholera toxin B and infection with Escherichia coli, Citrobacter rodentium or Vibrio cholerae. Caspase-11 rather than caspase-1 is the main offender involved in sepsis. Hence, caspase-11 plays an essential pro-inflammatory role in innate immune response to bacterial infections.
Bacterial Infections
;
Cholera Toxin
;
Citrobacter rodentium
;
Criminals
;
Escherichia coli
;
Humans
;
Immunity, Innate
;
Sepsis
;
Vibrio cholerae
4.cGAS-cGAMP Signaling and Antiviral Defense.
Zahid MANZOOR ; Young Sang KOH
Journal of Bacteriology and Virology 2014;44(1):112-114
Cyclic guanosine monophosphate-adenosine monophosphate (cGAMP) synthase (cGAS) is a cytosolic DNA sensor that plays an important role in innate immunity. Transfection of DNA or DNA virus infection results in the induction of type I interferon production in fibroblasts, macrophages, and dendritic cells which is dependent on cGAS. Recently, cGas (-/-) mice have been reported to be more vulnerable to fatal infection with herpes simplex virus 1 (HSV1) as compared to wild-type mice.
Animals
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Cytosol
;
Dendritic Cells
;
DNA
;
DNA Virus Infections
;
Fibroblasts
;
Guanosine
;
Herpesvirus 1, Human
;
Immunity, Innate
;
Interferon Type I
;
Macrophages
;
Mice
;
Transfection
5.Prevalence of Ascaridia galli in white leghorn layers and Fayoumi-Rhode Island red crossbred flock at government poultry farm Dina, Punjab, Pakistan
Hafiz Allah Bachaya ; Muhammad Asif Raza ; Muhammad Ashraf Anjum ; Imran Ahmad Khan ; Abdul Aziz ; Zahid Manzoor ; Shaukat Hussain Munawar
Tropical Biomedicine 2015;32(1):11-16
Poultry farming not only provides high nutritious food but also creates employment
opportunity for rural masses. Documented evidences elaborates that helminth parasitism is
most deciduous problem of chickens especially in developing world. Ascaridia (A.) galli, a
nematode of small intestine, has been considered as the most common and important parasite
of chicken. The present study was carried out to investigate prevalence and severity of A.
galli in White Leghorn layers (housing type: battery cage and deep litter, 50 each) and
Fayoumi-Rhode Island Red crossbred (male and female: 50 each) flock rearing at Government
Poultry Farm, Dina, Punjab, Pakistan. Two hundred faecal samples were examined by using
standard parasitological and McMaster egg counting technique. The overall prevalence was
24.5% at farm, 13% in White leghorn layer (battery cage=2%, deep litter=24%) and 36% in
Fayoumi-Rhode Island Red (male=34%, female=38%). It was also observed that White leghorn
layer rearing in deep litter had more severe infection (EPG=1920) of A. galli compare with
battery cages birds (EPG=500). Parasite prevalence was significantly related with sex (P<0.05)
in Fayoumi-Rhode Island Red and male birds had less number of average parasites (0.34±0.47)
as compared to females (0.38±0.490). Additionally, female birds were under serious threat of
infection (EPG=2270) compared with its counterpart (EPG=1250). Given the high infection
rates, particular attention should be paid to management and provision of feed supplement to
White leghorn layer housing in deep litter and female bird of Fayoumi-Rhode Island Red
crossbred.
6.Bacterial 23S Ribosomal RNA, a Ligand for Toll-like Receptor 13.
Zahid MANZOOR ; Young Sang KOH
Journal of Bacteriology and Virology 2012;42(4):357-358
Toll-like receptors are required for detection of pathogen-associated molecular patterns and play critical roles in protection of host from infection. Murine TLR13 was recently reported to be involved in recognition of bacterial 23S ribosomal RNA sequence that is the binding site of different antibiotics.
Anti-Bacterial Agents
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Binding Sites
;
RNA, Ribosomal, 23S
;
Staphylococcus aureus
;
Toll-Like Receptors
7.Mitogen-activated Protein Kinases in Inflammation.
Zahid MANZOOR ; Young Sang KOH
Journal of Bacteriology and Virology 2012;42(3):189-195
Mitogen-activated protein kinases (MAPKs) play critical regulatory roles in the production of the pro-inflammatory cytokines and downstream signaling events which lead to inflammation. Inflammation is a primarily localized and protective response of host against microbial infection. Controlled inflammation is beneficial and necessary for host defense while uncontrolled inflammatory response results in inflammatory diseases such as septic shock, rheumatoid arthritis and cancer. The MAPK family consists of three subfamilies; the extracellular signal-regulated kinases (ERKs), the c-Jun N-terminal kinases (JNKs), and the p38 MAPKs. MAPKs are involved in transmitting extracellular signals to nucleus which leads to gene regulation. In this review, we summarize the current knowledge of ERK1/2, JNKs, and p38 MAPK members and their roles in inflammation.
Arthritis, Rheumatoid
;
Cytokines
;
Extracellular Signal-Regulated MAP Kinases
;
Humans
;
Inflammation
;
Mitogen-Activated Protein Kinases
;
p38 Mitogen-Activated Protein Kinases
;
Phosphotransferases
;
Shock, Septic
8.Mitogen-activated Protein Kinase Signaling in Inflammation-related Carcinogenesis.
Zahid MANZOOR ; Jung Eun KOO ; Young Sang KOH
Journal of Bacteriology and Virology 2014;44(4):297-304
The role of mitogen-activated protein kinases (MAPKs) in regulation of inflammation is well known. MAPK family is activated by various stimuli and involved in transmitting extracellular signals to nucleus leading to gene regulation. Inflammation is primary defensive response of host against microbes. Controlled inflammation is helpful and indispensable for host defense. However, uncontrolled inflammatory response leads to various inflammatory diseases and cancer. Persistent inflammation leads to cell proliferation and survival that plays crucial role in tumorigenesis. In this review, we recapitulate the recent knowledge of MAPK signaling and its roles in inflammation-associated carcinogenesis.
Carcinogenesis*
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Cell Proliferation
;
Humans
;
Inflammation
;
Mitogen-Activated Protein Kinases
;
Protein Kinases*
9.A20 Protects Against Arthritis by Regulation of the NLRP3 Inflammasome.
Zahid MANZOOR ; Young Sang KOH
Journal of Bacteriology and Virology 2015;45(3):282-284
Rheumatoid arthritis is an autoinflammatory disease that primarily affects joints and is characterized by pervasive joint inflammation. A20/Tumor necrosis factor, alpha-induced protein 3 (Tnfaip3) inhibits activation of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kappaB) and has been associated with rheumatoid arthritis. However, the precise role of A20 in rheumatoid arthritis remains unclear. Deletion of A20/Tnfaip3 gene in mice elicits impulsive erosive polyarthritis that is similar to rheumatoid arthritis in patients. Recently, it has been shown that A20 protects against arthritis by regulating the NLRP3 inflammasome.
Animals
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Arthritis*
;
Arthritis, Rheumatoid
;
B-Lymphocytes
;
Humans
;
Inflammation
;
Joints
;
Mice
;
Necrosis
10.3-Hydroxy-4,7-megastigmadien-9-one, Isolated from Ulva pertusa Kjellman, Inhibits LPS-Induced Inflammatory Response by Down-Regulating Mitogen-Activated Protein Kinase and NF-κB Pathways.
Irshad ALI ; Zahid MANZOOR ; Young Sang KOH
Journal of Bacteriology and Virology 2016;46(3):167-172
In the present study we evaluated the anti-inflammatory potential of 3-hydroxy-4,7-megastigmadien-9-one (Comp) isolated from Ulva pertusa Kjellman, in LPS-stimulated bone marrow-derived dendritic cells (BMDCs). Comp treatment exhibited strong dose dependent inhibition of IL-12 p40 and IL-6 cytokine production with IC₅₀ values of 7.85 ± 0.32 and 7.86 ± 0.18, respectively in LPS-stimulated BMDCs. Treatment of Comp inhibited MAPKs and NF-κB pathways in LPS-stimulated BMDCs by inhibiting the phosphorylation of ERK1/2, JNK1/2, p38 and IκB. Thus, these results suggest that Comp have a significant anti-inflammatory property and affirm further studies concerning the potentials of Comp for medicinal use.
Dendritic Cells
;
Interleukin-12
;
Interleukin-6
;
Phosphorylation
;
Protein Kinases*
;
Ulva*