No description available.

published_or_final_version / Zoology / Master / Master of Philosophy

by Cheung Yeuk Siu. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves 141-153). / Abstracts in English and Chinese. / Acknowledgments --- p.i / Abstract --- p.ii / 摘要 --- p.iv / List of abbreviations --- p.v / Table of contents --- p.viii / Chapter Chapter 1 --- Introduction / Chapter 1.1 --- Prolactin (PRL) --- p.1 / Chapter 1.1.1 --- General introduction --- p.1 / Chapter 1.1.2 --- Genomic organization of teleost PRL gene --- p.2 / Chapter 1.1.3 --- Conserved domains of fish PRL --- p.3 / Chapter 1.1.4 --- Structure of teleost PRL --- p.6 / Chapter 1.1.5 --- Tissue sources of PRL --- p.8 / Chapter 1.2 --- Prolactin receptor (PRLR) --- p.9 / Chapter 1.2.1 --- Tissue distribution in teleosts --- p.9 / Chapter 1.2.2 --- Receptor structure and multiple forms of PRLR --- p.11 / Chapter 1.2.3 --- Possible action mechanisms of PRL --- p.14 / Chapter 1.3 --- Control of PRL release --- p.17 / Chapter 1.4 --- Biological functions of PRL in vertebrates --- p.19 / Chapter 1.4.1 --- Biological effects on teleosts --- p.19 / Chapter 1.4.1.1 --- Osmoregulatory roles --- p.20 / Chapter 1.4.1.2 --- Non-osmoregulatory roles --- p.29 / Chapter 1.5 --- Aim of the present study --- p.32 / Chapter Chapter 2 --- "Recombinant goldfish (Carassius auratus) prolactin: subcloning, expression, purification and refolding of the recombinant protein" / Chapter 2.1 --- Introduction --- p.35 / Chapter 2.2 --- Materials --- p.38 / Chapter 2.3 --- Methods --- p.48 / Chapter 2.3.1 --- Subcloning of the gfPRL cDNA --- p.48 / Chapter 2.3.1.1 --- PCR cloning of gfPRL cDNA --- p.48 / Chapter 2.3.1.2 --- DNA sequencing of the subcloned fragment --- p.51 / Chapter 2.3.1.3 --- Subcloning of the gfPRL cDNA fragment into the expression vector --- p.52 / Chapter 2.3.2 --- Expression and purification of rgfPRL --- p.53 / Chapter 2.3.2.1 --- Transformation of pRSETA/gfPRL into BL21(DE3)pLysS cells --- p.53 / Chapter 2.3.2.2 --- Prokaryotic expression of rgfPRL --- p.53 / Chapter 2.3.2.3 --- Affinity purification of rgfPRL --- p.55 / Chapter 2.3.2.4 --- Western blot analysis of the purified rgfPRL --- p.57 / Chapter 2.3.2.5 --- Protein concentration determination of the rgfPRL --- p.59 / Chapter 2.3.3 --- Protein refolding --- p.60 / Chapter 2.4 --- Results --- p.61 / Chapter 2.4.1 --- Subcloning and DNA sequencing of the gfPRL --- p.61 / Chapter 2.4.2 --- Expression and purification of rgfPRL --- p.63 / Chapter 2.4.2.1 --- Prokaryotic expression of rgfPRL --- p.63 / Chapter 2.4.2.2 --- Affinity purification of rgfPRL --- p.66 / Chapter 2.4.2.3 --- Western blot analysis of the purified rgfPRL --- p.68 / Chapter 2.4.2.4 --- Protein concentration determination of the rgfPRL --- p.68 / Chapter 2.4.3 --- Protein refolding --- p.70 / Chapter 2.5 --- Discussion --- p.72 / Chapter Chapter 3 --- Production of polyclonal antibodies against rgfRPL / Chapter 3.1 --- Introduction --- p.81 / Chapter 3.2 --- Materials --- p.82 / Chapter 3.3 --- Methods --- p.84 / Chapter 3.3.1 --- Immunization of rabbits --- p.84 / Chapter 3.3.2 --- Collection of the polyclonal antisera --- p.85 / Chapter 3.3.3 --- Purification of IgG from the polyclonal antisera --- p.86 / Chapter 3.3.4 --- Enzyme linked immunosorbent assay (ELISA) --- p.87 / Chapter 3.3.5 --- Western blot analysis for cross-reactivity --- p.88 / Chapter 3.4 --- Results --- p.90 / Chapter 3.4.1 --- Isolation and purification of IgG from the polyclonal antisera --- p.90 / Chapter 3.4.2 --- ELISA --- p.93 / Chapter 3.4.3 --- Western blot analysis for cross-reactivity --- p.96 / Chapter 3.5 --- Discussion --- p.98 / Chapter Chapter 4 --- Isolation of native PRL from goldfish pituitaries / Chapter 4.1 --- Introduction --- p.100 / Chapter 4.2 --- Materials --- p.101 / Chapter 4.3 --- Methods --- p.103 / Chapter 4.3.1 --- Alkaline extraction --- p.103 / Chapter 4.3.2 --- Size exclusion chromatography --- p.104 / Chapter 4.3.3 --- Anion exchange chromatography --- p.104 / Chapter 4.4 --- Results --- p.106 / Chapter 4.4.1 --- Size exclusion chromatography --- p.106 / Chapter 4.4.2 --- Anion exchange chromatography --- p.109 / Chapter 4.4.3 --- SDS-PAGE analysis and immuno-detection of the purified protein --- p.112 / Chapter 4.5 --- Discussion --- p.114 / Chapter Chapter 5 --- Receptor binding assays / Chapter 5.1 --- Introduction --- p.115 / Chapter 5.2 --- Materials --- p.117 / Chapter 5.3 --- Methods --- p.119 / Chapter 5.3.1 --- Gill membrane preparation --- p.119 / Chapter 5.3.2 --- Radioactive labelling of the primary ligand --- p.120 / Chapter 5.3.3 --- Determination of the percentage of 125I incorporation and specific radioactivity of the radioligand --- p.121 / Chapter 5.3.4 --- Membrane protein dependence assay --- p.122 / Chapter 5.3.5 --- Receptor binding study using rgfPRL --- p.124 / Chapter 5.4 --- Results --- p.125 / Chapter 5.4.1 --- Radioactive labelling of the primary ligand --- p.125 / Chapter 5.4.2 --- Determination of the percentage of 125I incorporation and specific radioactivity of the radioligand --- p.127 / Chapter 5.4.3 --- Membrane protein dependence assay --- p.129 / Chapter 5.4.4 --- Receptor binding study using rgfPRL --- p.131 / Chapter 5.5 --- Discussion --- p.133 / Chapter Chapter 6 --- General discussion and conclusion --- p.136 / References --- p.141

by Lee Tsz On. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves 148-155). / Abstracts in English and Chinese. / Abstract --- p.i / 摘要 --- p.iii / Acknowledgments --- p.v / Contents --- p.vi / List of figures --- p.xii / List of table --- p.xiv / Abbreviations --- p.xv / Chapter Chapter 1 --- General Introduction / Chapter 1.1. --- Growth hormone (GH) --- p.1 / Chapter 1.1.1. --- Introduction to GH --- p.1 / Chapter 1.1.2. --- Actions of GH --- p.2 / Chapter 1.1.3. --- Structure of GH --- p.3 / Chapter 1.1.4. --- The sequence of GH --- p.5 / Chapter 1.2. --- Growth hormone receptor (GHR) --- p.6 / Chapter 1.2.1 --- Introduction to GHR --- p.6 / Chapter 1.2.2. --- Structure of the extracellular domain of GHR --- p.9 / Chapter 1.2.3. --- The regulation of GHR --- p.12 / Chapter 1.2.4. --- GHR biosynthesis --- p.13 / Chapter 1.2.5. --- Tissue distribution of GHR --- p.14 / Chapter 1.3. --- Signal transduction mechanisms of GHR --- p.15 / Chapter 1.3.1. --- Dimerization of GH and GHR complex --- p.15 / Chapter 1.3.2. --- The Jak and Stat pathway --- p.18 / Chapter 1.3.3. --- The ras and other signaling pathways --- p.20 / Chapter 1.4. --- Project aim --- p.22 / Chapter Chapter 2 --- Material and Methods / Chapter 2.1. --- Preparation of ribonuclease free reagents and apparatus --- p.23 / Chapter 2.2. --- Isolation of total RNA --- p.23 / Chapter 2.3. --- Isolation of mRNA --- p.24 / Chapter 2.4. --- Spectrophotometric quantification and qualification of DNA and RNA --- p.24 / Chapter 2.5. --- First strand cDNA synthesis --- p.25 / Chapter 2.6. --- Agarose gel electrophoresis of DNA --- p.25 / Chapter 2.7. --- Formaldehyde agarose gel electrophoresis of RNA --- p.26 / Chapter 2.8. --- Vacuum transfer of DNA to a nylon membrane --- p.26 / Chapter 2.9. --- Nucleic acids purification by MicroSpin (S-200HR) columns --- p.27 / Chapter 2.10. --- DNA radioactive labeling by nick translation --- p.27 / Chapter 2.11. --- Southern blot analysis --- p.28 / Chapter 2.12. --- Autoradiography and molecular imager --- p.28 / Chapter 2.13 . --- Linearization and dephosphorylation of plasmid DNA --- p.29 / Chapter 2.14. --- Purification of DNA from agarose using QIAEX II kit --- p.29 / Chapter 2.15. --- 3'End modification of PCR amplified DNA --- p.30 / Chapter 2.16. --- Ligation of DNA fragments to linearized vector --- p.30 / Chapter 2.17. --- Preparation of Escherichia coli competent cells --- p.31 / Chapter 2.18. --- Transformation --- p.31 / Chapter 2.19. --- Mini preparation of plasmid DNA --- p.32 / Chapter 2.20. --- Maxi preparation of plasmid DNA --- p.34 / Chapter 2.21 . --- PCR sequencing --- p.35 / Chapter 2.22. --- cDNA library screening --- p.36 / Chapter 2.23. --- Preparation and sterilization of culture medium --- p.38 / Chapter 2.24. --- Preparation of frozen stock of culture cells --- p.39 / Chapter 2.25. --- Cell passage of CHO-Kl --- p.39 / Chapter 2.26. --- Counting of cells --- p.40 / Chapter 2.27. --- Proliferation assay performed on CHO-K1 cells (MTT method) --- p.40 / Chapter 2.28. --- Luciferase assay --- p.41 / Chapter 2.29. --- SDS-PAGE preparation --- p.42 / Chapter 2.30. --- SDS-PAGE analysis of proteins --- p.42 / Chapter 2.31 . --- Recombinant protein expression --- p.43 / Chapter 2.32. --- Small scale purification of recombinant proteins --- p.44 / Chapter 2.33. --- Restriction digestion of DNA --- p.45 / Chapter 2.34. --- Purification of PCR product using QIAquick PCR purification kit --- p.45 / Chapter 2.35. --- TA cloning of PCR fragment --- p.45 / Chapter 2.36. --- Transfection of plasmid into CHO-K1 cells --- p.46 / Chapter 2.37. --- Sources of hormones --- p.46 / Chapter 2.38. --- Buffer and reagents --- p.47 / Chapter Chapter 3 --- "Cloning, expression and tissue distribution of Xenopus laevis GHR" / Chapter 3.1. --- Introduction --- p.50 / Chapter 3.2. --- Materials and methods --- p.51 / Chapter 3.2.1. --- Molecular cloning of xGHR cDNA / Chapter 3.2.1.1. --- Animals and tissues --- p.51 / Chapter 3.2.1.2. --- Reverse transcribed´ؤpolymerase chain reaction (RT-PCR) --- p.51 / Chapter 3.2.1.3. --- Subcloning of PCR amplified DNA fragment --- p.53 / Chapter 3.2.1.4. --- Library screening of xGHR --- p.53 / Chapter 3.2.1.5. --- 5 'Rapid amplification of cDNA end (5' RACE) --- p.55 / Chapter 3.2.2. --- Tissue distribution of xGHR / Chapter 3.2.2.1. --- Animals and tissues --- p.56 / Chapter 3.2.2.2. --- RT-PCR and Southern blot --- p.56 / Chapter 3.2.3. --- Eukarytoic expression of xGHR and functional assay of xGHR / Chapter 3.2.3.1. --- Subcloning ofxGHR into pRc/CMV --- p.57 / Chapter 3.2.3.2. --- Expression of xGHR in CHO-K1 cell --- p.58 / Chapter 3.2.3.3. --- Proliferation assay --- p.58 / Chapter 3.3. --- Results --- p.60 / Chapter 3.3.1. --- RT-PCR of the partial fragment --- p.60 / Chapter 3.3.2. --- Library screening of xGHR cDNA library --- p.61 / Chapter 3.3.3. --- 5' RACE --- p.64 / Chapter 3.3.4. --- The full-length cDNA sequence of xGHR --- p.65 / Chapter 3.3.5. --- Tissue distribution of xGHR mRNA --- p.69 / Chapter 3.3.6. --- Functional assay of xGHR in CHO-K1 cells --- p.71 / Chapter 3.4. --- Discussion --- p.74 / Chapter Chapter 4 --- Cloning and expression of Xenopus laevis GH-A and GH-B / Chapter 4.1. --- Introduction --- p.78 / Chapter 4.2. --- Materials and Methods --- p.79 / Chapter 4.2.1. --- PCR amplification of xGH-A and xGH-B partial fragments --- p.79 / Chapter 4.2.2. --- cDNA library screening of xGH-A and xGH-B --- p.80 / Chapter 4.2.3. --- Rapid amplification of cDNA ends of xGH-B / Chapter 4.2.3.1. --- 3'RACE --- p.80 / Chapter 4.2.3.2. --- 5'RACE --- p.81 / Chapter 4.2.4. --- Expression of xGH-A and xGH-B / Chapter 4.2.4.1 --- Construction of the expression vector --- p.84 / Chapter 4.2.4.2. --- Protein expression of xGH-A and xGH-B --- p.85 / Chapter 4.2.5. --- Purification of recombinant xGH-A and xGH-B --- p.85 / Chapter 4.3. --- Results --- p.87 / Chapter 4.3.1. --- PCRof xGH-A and xGH-B partial fragment --- p.87 / Chapter 4.3.2. --- Library screening of xGH-A --- p.87 / Chapter 4.3.3. --- 5' RACE and 3' RACE of xGH-B --- p.91 / Chapter 4.3.4. --- Sequence analysis of xGH-A and xGH-B --- p.93 / Chapter 4.3.5. --- Protein expression and purification of recombinant xGH-A and xGH-B --- p.100 / Chapter 4.4. --- Discussion --- p.102 / Chapter Chapter 5 --- Molecular cloning and function expression of goldfish GHR / Chapter 5.1. --- Introduction --- p.105 / Chapter 5.2. --- Materials and methods --- p.106 / Chapter 5.2.1. --- Molecular cloning of the partial fragment of gfGHR / Chapter 5.2.1.1. --- Primer design --- p.106 / Chapter 5.2.1.2. --- Library PCR of gfGHR partial fragment --- p.108 / Chapter 5.2.2. --- Library PCR of gfGHR cDNA sequence --- p.110 / Chapter 5.2.3. --- Determination of 3' End and 5' End sequences of gfGHR cDNA --- p.112 / Chapter 5.2.4. --- Tissue distribution of gfGHR / Chapter 5.2.4.1. --- Animals and tissues --- p.115 / Chapter 5.2.4.2. --- Semi-quantitative R T-PCR --- p.115 / Chapter 5.2.5. --- Functional expression of gfGHR in CHO-K1 cell / Chapter 5.2.5.1. --- Construction of an expression vector containing gfGHR --- p.116 / Chapter 5.2.5.2. --- Functional assay of gfGHR expression on CHO-K1 cells --- p.117 / Chapter 5.2.5.3. --- Proliferation assay --- p.118 / Chapter 5.2.5.4. --- Spi luciferase assay --- p.118 / Chapter 5.3. --- Results --- p.120 / Chapter 5.3.1. --- PCR amplification of the partial sequence of gfGHR --- p.120 / Chapter 5.3.2. --- The library PCR of gfGHR cDNA sequence --- p.122 / Chapter 5.3.3. --- The sequence of gfGHR --- p.124 / Chapter 5.3.4. --- Tissue distribution of gfGHR --- p.131 / Chapter 5.3.5. --- Proliferation assay --- p.133 / Chapter 5.3.6. --- Spi luciferase assay --- p.135 / Chapter 5.4. --- Discussion --- p.137 / Chapter Chapter 6 --- General discussion and future works --- p.145 / References --- p.148 / Appendix --- p.156

Yam Kwan Mei. / Thesis submitted in: August 1999. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves 108-129). / Abstracts in English and Chinese. / Abstract (in English) --- p.ii / Abstract (in Chinese) --- p.iv / Acknowledgement --- p.vi / Table of Contents --- p.ix / List of Tables --- p.xiv / List of Figures --- p.xv / Symbols and Abbreviations --- p.xviii / Scientific names --- p.xx / Chapter Chapter 1 --- General Introduction --- p.1 / Chapter 1.1 --- Gonadotropins --- p.1 / Chapter 1.1.1 --- Structure --- p.1 / Chapter 1.1.2 --- Function --- p.3 / Chapter 1.1.3 --- Regulation --- p.9 / Chapter 1.1.3.1 --- GnRH --- p.9 / Chapter 1.1.3.2 --- Steroids --- p.11 / Chapter 1.1.3.3 --- Activin --- p.12 / Chapter 1.2 --- Activin Family of Growth Factors --- p.14 / Chapter 1.2.1 --- Structure --- p.14 / Chapter 1.2.2 --- Function --- p.17 / Chapter 1.3 --- Objectives --- p.22 / Chapter Chapter 2 --- Cloning of Goldfish Activin βA cDNA and the Expression of Its mRNA in Gonadal and Non-gonadal Tissues --- p.24 / Chapter 2.1 --- Introduction --- p.24 / Chapter 2.2 --- Materials and Methods --- p.25 / Chapter 2.2.1 --- Cloning of goldfish activin βA cDNA --- p.26 / Chapter 2.2.1.1 --- Cloning of the 5' and 3' cDNA ends --- p.26 / Chapter 2.2.1.2 --- Extension of the 5' and 3' fragments --- p.28 / Chapter 2.2.2 --- Sequencing of the cDNA --- p.28 / Chapter 2.2.2.1 --- Generation of pKS/GactβA constructs with insert in different orientations --- p.28 / Chapter 2.2.2.2 --- Generation of overlapping subclones --- p.29 / Chapter 2.2.2.3 --- Cycle sequencing --- p.30 / Chapter 2.2.2.4 --- Sequence analyses --- p.30 / Chapter 2.2.3 --- Isolation of total and messenger RNA --- p.30 / Chapter 2.2.3.1 --- Isolation of total RNA --- p.30 / Chapter 2.2.3.2 --- Isolation of messenger RNA --- p.31 / Chapter 2.2.4 --- Southern blot analysis --- p.32 / Chapter 2.2.5 --- Northern blot analysis --- p.33 / Chapter 2.2.6 --- Reverse transcription-polymerase chain reaction (RT-PCR) --- p.33 / Chapter 2.3 --- Results --- p.35 / Chapter 2.3.1 --- Cloning and sequence analysis of activin β A cDNA --- p.35 / Chapter 2.3.2 --- Distribution of activin βA mRNA in different tissues --- p.49 / Chapter 2.4 --- Discussion --- p.53 / Chapter Chapter 3 --- Establishment and Characterization of Stable Cell Lines for the Recombinant Production of Goldfish Activin A --- p.59 / Chapter 3.1 --- Introduction --- p.59 / Chapter 3.2 --- Materials and Methods --- p.60 / Chapter 3.2.1 --- Construction of expression plasmid --- p.60 / Chapter 3.2.2 --- Cell culture --- p.62 / Chapter 3.2.3 --- Transfection of CHO cells --- p.62 / Chapter 3.2.4 --- G418 selection of transfected CHO cells --- p.62 / Chapter 3.2.5 --- Activin bioassay (EDF-assay) --- p.63 / Chapter 3.2.6 --- Cloning of pBK/GactβA-transfected CHO cells by limited dilution --- p.63 / Chapter 3.2.7 --- Isolation of total RNA --- p.65 / Chapter 3.2.8 --- Northern blot analysis --- p.65 / Chapter 3.3 --- Results --- p.66 / Chapter 3.3.1 --- Optimization of G418 concentration for selection --- p.66 / Chapter 3.3.2 --- Expression of activin activity by pBK/GactpβA- transfected CHO cells --- p.67 / Chapter 3.3.3 --- Establishment and characterization of CHO cell lines that stably produce recombinant goldfish activin A --- p.67 / Chapter 3.4 --- Discussion --- p.73 / Chapter Chapter 4 --- Differential Regulation of Goldfish Gonadotropin (GTH-Iβ and GTH-IIβ) Gene Expression by Recombinant Goldfish Activin --- p.79 / Chapter 4.1 --- Introduction --- p.79 / Chapter 4.2 --- Materials and Methods --- p.82 / Chapter 4.2.1 --- Animals --- p.82 / Chapter 4.2.2 --- Drug treatment --- p.83 / Chapter 4.2.3 --- Primary culture of dispersed pituitary cells --- p.84 / Chapter 4.2.4 --- Southern blot analysis --- p.85 / Chapter 4.2.5 --- Isolation of total RNA --- p.86 / Chapter 4.2.6 --- Northern blot analysis --- p.86 / Chapter 4.2.7 --- Dot blot analysis --- p.87 / Chapter 4.2.8 --- Data analyses --- p.87 / Chapter 4.3 --- Results --- p.88 / Chapter 4.3.1 --- Probe specificity --- p.88 / Chapter 4.3.2 --- Effects of goldfish activin on pituitary GTH-Iβ and -IIβ mRNA expression --- p.88 / Chapter 4.3.3 --- Blockade of activin effects by follistatin --- p.92 / Chapter 4.4 --- Discussion --- p.96 / Chapter Chapter 5 --- General Discussion --- p.101 / Chapter 5.1 --- Overview --- p.101 / Chapter 5.2 --- Contribution of the Present Research --- p.103 / Chapter 5.2.1 --- Cloning of full-length goldfish activin βA cDNA --- p.103 / Chapter 5.2.2 --- Establishment of stable cell lines for the recombinant production of goldfish activin A --- p.104 / Chapter 5.2.3 --- Differential regulation of goldfish gonadotropin (GTH-Iβ and GTH-IIβ) gene expression by recombinant goldfish activin --- p.105 / Chapter 5.3 --- Future Research Direction --- p.107 / Chapter 5.3.1 --- Activin studies --- p.107 / Chapter 5.3.2 --- Gonadotropin studies --- p.107 / References --- p.108

published_or_final_version / Zoology / Master / Master of Philosophy

published_or_final_version / Zoology / Master / Master of Philosophy

No description available.

Patterns of proliferation and changes in total cell number in the optic nerve, tract and tectum of goldfish have been examined following optic nerve crush or optic enucleation, using bromodeoxyuridine to label the proliferating cells. In general, an increase in proliferation and total cell number in all parts of the visual system was observed peaking between 7 and 14 days and resolving itself to normal or near normal levels by 32 days postoperative. Enucleation resulted in elevated proliferation values as compared to animals with an optic nerve crush, at least one early timepoint in each part of the visual system, but overall, there is little to suggest that axons are exerting a major effect on the cellular response. Finally, a seasonal effect on the proliferative response of non-neuronal cells and axonal regrowth has been demonstrated. Fish acclimatized under autumn-like conditions showed a faster initiation of the non-neuronal cell response and an enhanced rate of axonal regrowth when compared to fish acclimatized under spring-like conditions. It is believed that photoperiod plays a major role in the seasonal effects observed with temperature playing only a minor one.

This study aims at providing a new technique for the isolation and culture of goldfish microglial cells. So far no protocol has been designed for the growth of these cells in vitro, despite the growing interest in the remarkable capacity of goldfish central nervous system (CNS) for regenerating severed axons. This newly developed technique has little or no similarity to those used in the isolation of mammalian microglia, and is distinguished by its simple setup and its fast yield for microglial cells. In addition, a virtually pure population of microglia was generated when plated on untreated plastic dishes, eliminating further need for purification. This technique may thus provide a starting point for future characterization of the microglial cells in vitro, which may eventually help toward building a better understanding of the function and biology of these cells. A preliminary morphological characterization of the cells has also been conducted, in addition to groundwork experiments on the phagocytic activity of these cells in vitro, using myelin to stimulate phagocytosis. These assays were oriented toward providing a comparison to the mammalian cultures of microglia, and so far, displayed several similarities in morphologies and phagocytosis.