@misc{qureshi_heggen_hussain_2000, title={Avian macrophage: effector functions in health and disease}, volume={24}, ISSN={["0145-305X"]}, DOI={10.1016/S0145-305X(99)00067-1}, abstractNote={Monocytes-macrophages, cells belonging to the mononuclear phagocytic system, are considered as the first line of immunological defense. Being mobile scavenger cells, macrophages participate in innate immunity by serving as phagocytic cells. These cells arise in the bone marrow and subsequently enter the blood circulation as blood monocytes. Upon migration to various tissues, monocytes mature and differentiate into tissue macrophages. Macrophages then initiate the 'acquired' immune response in their capacity as antigen processing and presenting cells. While responding to their tissue microenvironment or exogenous antigenic challenge, macrophages may secrete several immunoregulatory cytokines or metabolites. Being the first line of immunological defense, macrophages therefore represent an important step during interaction with infectious agents. The outcome of the macrophage-pathogen interaction depends upon several factors including the stage of macrophage activation, the nature of the infectious agent, the level of genetic control on macrophage function as well as environmental and nutritional factors that may modulate macrophage activation and functions. Research in avian macrophages has lagged behind that in mammals. This has been largely due to the lack of harvestable resident macrophages from the chicken peritoneal cavity. However, the development of elicitation protocols to harvest inflammatory abdominal macrophages and the availability of transformed chicken macrophage cell lines, has enabled researchers to address several questions related to chicken macrophage biology and function in health and disease. In this manuscript the basic profiles of several macrophage effector functions are described. In addition, the interaction of macrophages with various pathogens as well as the effect of genetic and environmental factors on macrophage functional modulation is described.}, number={2-3}, journal={DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY}, author={Qureshi, MA and Heggen, CL and Hussain, I}, year={2000}, pages={103–119} }
 @article{hussain_qureshi_1998, title={The expression and regulation of inducible nitric oxide synthase gene differ in macrophages from chickens of different genetic background}, volume={61}, ISSN={["1873-2534"]}, DOI={10.1016/S0165-2427(97)00153-0}, abstractNote={It has been previously reported that lipopolysaccharide (LPS)-stimulated macrophages from Cornell K-Strain chickens (B15B15) and a transformed cell line, MQ-NCSU, (broiler origin) produced significantly higher levels of inducible nitric oxide synthase (iNOS) mRNA than macrophages isolated from GB1 (B13B13) and GB2 (B6B6) chickens. The purpose of this study was to determine the basis of such differential iNOS gene expression and to study the relationship of high or low expression of iNOS mRNA with iNOS enzyme activity in macrophages from GB2 (low iNOS mRNA expresser), K-strain and MQ-NCSU (high iNOS mRNA expressers). The enzyme activity in lysates from LPS-stimulated macrophages was lower in GB2 (range: 23 to 41 μM, P<0.05) as compared with the K-strain and MQ-NCSU macrophages that exhibited intermediate (range: 27 to 59 μM) and the highest (range: 144 to 217 μM) activity, respectively. Total RNA collected from LPS-treated macrophages at various time-points post-actinomycin D treatment revealed comparable iNOS mRNA levels in MQ-NCSU, GB2, and K-strain macrophages, suggesting that post-transcriptional regulation mechanism(s) do not account for the difference in iNOS mRNA expression. To determine if differences in the transcription rate are the basis of the differential iNOS gene expression, macrophages were stimulated with or without LPS and nuclei-isolated. Inducible NOS mRNA probes were generated and hybridized with immobilized iNOS cDNA (reverse Northern blot). The resulting lumigraph yielded enhanced transcriptional activity from K-strain and MQ-NCSU macrophages whereas this activity was lower in GB2 macrophages. Therefore, these studies suggest that the previously reported genetically-based difference in iNOS mRNA expression further translates into differences in iNOS enzyme activity, and that the iNOS gene in chickens is transcriptionally regulated.}, number={2-4}, journal={VETERINARY IMMUNOLOGY AND IMMUNOPATHOLOGY}, author={Hussain, I and Qureshi, MA}, year={1998}, month={Feb}, pages={317–329} }
 @article{qureshi_hussain_heggen_1998, title={Understanding immunology in disease development and control}, volume={77}, ISSN={["0032-5791"]}, DOI={10.1093/ps/77.8.1126}, abstractNote={Two functional aspects of the avian immune system, the humoral and the cell-mediated arms, provide the basis for the preventive and protective response against disease-causing microorganisms. On the other hand, certain avian diseases may induce a transient or permanent immunosuppressive state in one or both of these arms, leading to increased disease susceptibility. In addition to the classical immune response, manifested as antibody production or effector cell activation several cytokines and metabolites are also produced. The consequence of cytokine- and metabolite-mediated microenvironments may be either beneficial or result in a noninfectious immunopathology. Nevertheless, the integrity of the immune system and its functional modulation by factors such as genetics, nutrition, and prophylactic approaches continue to be an important focus of attention in current poultry research and production efforts.}, number={8}, journal={POULTRY SCIENCE}, author={Qureshi, MA and Hussain, I and Heggen, CL}, year={1998}, month={Aug}, pages={1126–1129} }
 @article{hussain_qureshi_1997, title={Nitric oxide synthase activity and mRNA expression in chicken macrophages}, volume={76}, ISSN={["0032-5791"]}, DOI={10.1093/ps/76.11.1524}, abstractNote={The activity of inducible nitric oxide synthase (iNOS) enzyme was quantified in chicken macrophages. Macrophages from Cornell K-strain (B15B15), GB1 (B13B13), and GB2 (B6B6) chickens and a transformed cell line (MQ-NCSU) were incubated with or without varying concentrations of bacterial lipopolysaccharide (LPS). The culture supernatants were tested for the presence of nitrite. Macrophages from either source produced minimal nitrite (< 4.4 microM/1 x 10(6) cells) levels without LPS stimulation. However, nitrite levels produced by K-strain (42 microM) and MQ-NCSU (41 microM) macrophages were higher (P < 0.05) than those produced by the GB1 (14 microM) and GB2 (14 microM) per 1 x 10(6) macrophages with optimum LPS concentration range of 50 ng to 1 microgram/mL. The addition of an L-arginine analog, NGMMLA, at a concentration of 200 microM completely abolished nitrite production. The addition of 10% vol/vol lymphokines exhibited an additive effect on nitrite production in conjunction with LPS. The increased nitrite production by the K-strain and MQ-NCSU macrophages corresponded to an increased expression of iNOS mRNA as compared to the mRNA produced by GB1 and GB2 macrophages. The iNOS mRNA kinetics study revealed that mRNA levels peaked between 6 to 12 h. The cells from avian lymphoid lineage failed to produce any detectable iNOS activity. These studies showed that macrophages from varying sources differ in NOS activity and implied that genetic background may dictate the extent of arginine-mediated contribution in various biological and immunological functions.}, number={11}, journal={POULTRY SCIENCE}, author={Hussain, I and Qureshi, MA}, year={1997}, month={Nov}, pages={1524–1530} }