Glossary Active immunity Immunity acquired actively following infection or immunisation by vaccines. Addison's disease Disease resulting from destruction of adrenal glands, characterised by weakness, debility and very great suscepti- bility to the stress of infection, trauma, etc. Other features include spontaneous hypoglycaemia and pigmentation. Adjuvant A material that enhances the immune response to an antigen. Agglutination Clumping together of proteins (in antigen-antibody reactions) or microorganisms, or red blood cells (haemagglutination). Agonist Something that stimulates a biological response by occupy- ing cell receptors. Aleutian disease virus This virus infects mink and causes a fatal immunopathological disease in the type of mink that are homozy- gous for a recessive gene conferring the Aleutian coat colour. Anamnestic response Secondary immune response (see Primed). Anterior horn cells The main motor neurons in the anterior horn (as seen in cross-section) of the spinal cord, supplying striated muscle. Antigen presentation Display on the cell surface of processed peptides in combination with MHC proteins. Antigen processing Proteolytic digestion of a protein to form peptides which combine with MHC proteins to be presented on the cell surface to specifically reactive T cells. Antigenic determinant (= epitope) The small site on the antigen to which antibody attaches. Large antigens such as proteins carry several different antigenic determinants on the molecule, against which several different antibodies are formed. Antigenic site A cluster of epitopes/antigenic determinants (q.v.). Apoptosis Death of a cell in which it rounds up and is phagocy- tosed. It is not lysed. Involved in the natural regulation of cell numbers in tissues and occurs as the result of signals transmitted by adjoining cells. Is triggered by some viruses and inhibited by others (see Ch. 8). 427 428 Mims" Pathogenesis of Infectious Disease Arthus response Inflammatory reaction formed at the site where antigen is given to an animal possessing precipitating antibody to that antigen. Characteristically, oedema, haemorrhage and necrosis appear after a few hours ('immediate hypersensitivity'), and comple- ment, polymorphs and platelets are involved in the reaction. Attenuated Reduced in virulence for a given host, often as a result of continued growth of a microorganism in an artificial host or culture system. Autoimmunity Immunity (humoral or cell mediated) to antigens of the body's own tissues. Can cause tissue damage and disease, but also occurs as a harmless consequence of tissue damage. Avidity Refers to the strength of binding of I> 2-valent antibodies to multivalent antigens. (Affinity is a more precisely used term refer- ring to the strength of binding of one antibody combining site to a monovalent antigen.) Babesia Intracellular protozoan parasites of deer, cattle, rodents, humans, causing the disease babesiosis. Transmitted by ticks. Occur in Africa, North America, Asia, Europe; more than 70 species. Similar to Plasmodia (malaria parasites) and multiply in red blood cells. Bacterial cell wall Constitutes up to 20% dry weight of cell. Basically peptidoglycan (= mucopeptide = polymer of aminosugars cross-linked by peptide chains) containing components unique to microorganisms (e.g. muramic acid). Peptidoglycan may constitute nearly all of wall (certain Gram-positive bacteria), sometimes with additional polysaccharides and teichoic acids. Gram-negative bacte- rial cell walls are mostly lipopolysaccharides and lipoproteins, with little mucopeptide (p. 94). Bacteriocin Complex bacteriocidal substance released by certain bacteria, active against related bacteria, e.g. colicins produced by E. coli; pyocins produced by Pseudomonas aeruginosa. Basement membrane A sheet of material up to 0.2 lam thick lying immediately below epithelial (and endothelial) cells and supporting them. Contains glycoproteins and collagen and to some extent acts as a diffusion barrier for microorganisms. Thickness and structure varies in different parts of the body. B-cells Population of lymphoid cells derived from bone marrow developing without the need for the thymus. Differentiate to form antibody-producing cells. Compose 10-20% circulating lymphocytes in man. Capsid Protein coat enclosing the nucleic acid core of a virus. CD (cluster differentiation) antigens Antigens on cell surfaces, serving various functions and used to identify different cell types (e.g. CD4 on helper T-cells). More than 100 different CDs are described. Cell-mediated immunity (CMI) Specific immunity mediated by and transferrable to other individuals by cells (T cells), not by serum. Glossary 429 Challenge Administration of antigen or pathogen to provoke an immune reaction, usually in a primed individual. Chemokines Small molecular weight molecules acting as chemo- attractants and activators of lymphocytes and macrophages. There are four families defined by the position of the first two cysteines in their sequence: CC (27 members), CXC (15 members), CX3C (1 member), and C (2 members). They bind specifically to a seven- transmembrane G-protein-coupled receptor, for which there exists an equally diverse family of chemokine receptors. Coccus Spherical or ovoid bacterium. Colicins See Bacteriocin. Commensal ('table-companion') Associated with a host, often deriving nourishment from host, but neither beneficial nor harmful. Complement An enzymic system of serum proteins, made up of nine components (C1-C9) that are sequentially activated in many antigen-antibody reactions. It is a unique cascade system in which a small triggering event is amplified into a large response. Complement can also be activated directly, without an initial antigen-antibody reaction; this is the alternate complement path- way. Complement is involved in immune lysis of bacteria, and of some viruses and other microorganisms. It plays a part in phagocytosis, opsonisation, chemotaxis and the inflammatory response. Connective tissue Forms an all-pervading matrix, connecting and supporting muscles, nerves, blood vessels, etc. Consists of a muco- polysaccharide 'ground substance' containing cells (fibroblasts, histiocytes, etc.), collagen and elastic fibres. C-reactive protein A protein with subunits of M~ 24 300 that happens to react with the C carbohydrate of the pneumococcus. It is synthesised in the liver and is detectable in the serum when inflam- mation or tissue necrosis has taken place. It binds to substances from microorganisms and damaged tissues, activating the comple- ment system. Cryptococcus neoformans A yeast-like fungus found universally in soil, occasionally causing local or generalised infection in man. Cushing's syndrome A disease resulting from excessive secretion of hormones from the adrenal cortex. Patients show wasting of muscle and bone, fat deposits on face, neck and back, and small blood vessels are easily ruptured. Cytokines A group of at least 20 proteins, including interferons and interleukins. They are the hormones of the immune system, medi- ating interactions between immune cells, and having pathological as well as protective actions on infectious diseases. Defective virus replication Incomplete virus replication, with production only of viral nucleic acid, proteins or noninfectious virus particles. 430 Mires' Pathogenesis of Infectious Disease Defensins Peptides present in tears and in phagocytes that act against and destroy many microbes (bacteria, viruses, fungi) by punching holes in outer membranes. Delayed-type hypersensitivity (DTH) Hypersensitivity reaction visible 1-2 days after introduction (usually intradermally) of antigen into a sensitised individual. An expression of cell-mediated immu- nity (cf. Arthus reaction). Dendritic cell A large, specialized antigen-presenting cell with long tree-like (dendritic) processes, present in lymphoid tissues; not phagocytic and does not bear Fc receptors. Similar to Langerhan's cell in skin. Dorsal root ganglia A series of ganglia lying dorsal to the spinal cord (as seen in cross-section). Contain cell bodies of principal sensory neurons, each receiving impulses along fibres from skin, etc., and sending impulses along shorter fibres to spinal cord. ELAM-1 Endothelial cell leucocyte adhesion molecule-1. Inflam- matory mediator, binds to polymorphs, enabling them to stick to endothelial cells lining capillaries and venules. Enanthem Lesions of mucosae (e.g. mouth, intestines) in virus infec- tions (cf. Exanthem). Endocytosis The uptake of material by the cell into membrane- lined vesicles in the cytoplasm. The term includes pinocytosis (uptake of fluids) and phagocytosis (uptake of particles). Endogenous pyrogen (= Interleukin-1) Substance released from leucocytes (in man) acting on hypothalamus to produce fever. Endotoxin (q.v.) causes fever by liberating endogenous pyrogen. Endotoxin Toxic component associated with cell wall or micro- organism. Generally refers to lipopolysaccharide of Gram-negative bacilli, the toxic activity being due to lipid A (see Fig. 4.4 and Fig. 8.15). Enterotoxin Toxin acting on intestinal tract. Envelope Limiting membrane of virus derived from infected host- cell membrane. Exanthem Skin rash in virus infections (cf. Enanthem). Exotoxin Toxin actively secreted (e.g. cholera toxin) or released by autolysis from microorganism (e.g. tetanus toxin). Fimbriae (pili) Thread-like processes (not flagella) attached to cell walls of certain bacteria, often mediating attachment to host epithe- lial cell. Fomites Comprehensive word for patients' bedding, clothes, towels, and other personal possessions that may transmit infections. Germinal centre A rounded aggregation of lymphocytes, lympho- blasts, dendritic cells and macrophages. Germinal centres develop in primary nodules (follicles) of lymphoid tissue in response to anti- genic stimuli. Gram-negative Losing the primary violet or blue during decolorisa- tion in Gram's staining method. The method, developed by Hans Glossary 431 Gram, a Danish physician, in 1884, gives a simple and convenient distinction between groups of bacteria. The staining reaction reflects differences in cell wall composition (see Fig. 4.4), but the mechanism is not clear. Gram-positive Retaining the primary violet or blue stain in Gram's method. Granuloma A local accumulation of densely packed macrophages, often fusing to form giant cells, together with lymphocytes and plasma cells. Seen in chronic infections such as tuberculosis and syphilis. tIaemolysis Destruction of red blood cells. Caused by bacterial toxins, or by the action of complement on red cells coated with specific antibody. ttapten A small molecule which is antigenic (combines with anti- body) but is not immunogenic, i.e. does not induce an immune response in vivo unless attached to a larger ('carrier') molecule. Heat shock proteins (hsp) A family of proteins that control the correct folding of other proteins, acting as 'molecular chaperones'. They are induced in both microbe and phagocyte during the stress of infection (e.g. raised body temperature); and also have immunolog- ical roles (e.g. in antigen processing). Heterophile antibody Antibody to heterophile antigens which are present on the surface of cells of many different animal species. HLA (see MHC). Horizontal transmission The transmission of infection from indi- vidual to individual in a population rather than from parent to offspring. Humoral immunity Specific immunity mediated by antibodies. ICAM-1 Intercellular adhesion molecule-1. Immune complex A complex of antigen with its specific antibody. Immune complexes may be soluble or insoluble, and may be formed in antibody excess, antigen excess, or with equivalent proportions of antibody and antigen. They may contain complement components. Immune tolerance An immunologically specific reduction in immune responsiveness to a given antigen. Immunopathology Pathological changes partly or completely caused by the immune response. Infarction Obstruction of blood supply to a tissue or organ. Integrin A family of at least 18 cell adhesion receptors (e.g. fibrinogen receptor, laminin receptor) expressed on many cell types, mediating adhesion of cells to each other or to extracellular compo- nents. After interaction of integrin with ligand, vital signals affecting differentiation, proliferation, etc. are transmitted to the cell interior. Interleukins Cytokines; a group of 18 different proteins, all of them cloned and sequenced, that carry vital signals between different immune cells. 432 Mims" Pathogenesis of Infectious Disease Interleukin-1 (= endogenous pyrogen) Produced by macrophages, promotes activation and mitosis ofT and B cells. Causes fever as well as a variety of effects on muscle cells, fibroblasts and osteoblasts. Interleukin-2 Produced by T (especially Th) cells; essential for the continued proliferation (clonal expansion) of activated T cells. Interleukin-3 Multicolony stimulating factor; stimulates precursor cells (e.g. in bone marrow) to divide and form colonies of polymorphs, monocytes, etc. In vitro 'In glass', that is to say not in a living animal or person. In vivo In a living animal or person. Kinins Low molecular weight peptides generated from precursors in plasma or tissues and functioning as important mediators of inflam- matory responses. C2 kinin is derived from complement, and other kinins from a2-globulins. Lactate dehydrogenase elevating virus A virus that commonly infects mice, and multiplies only in macrophages. The macrophages fail to remove certain endogenous enzymes from the blood and an infected mouse is identified because there is a rise in the level of plasma lactate dehydrogenase. Infection is lifelong, and there are no pathological lesions or harmful effects. Latency Stage of persistent infection in which a microorganism causes no disease, but remains capable of activation and disease production. LD5o (lethal dose 50) Dose that kills 50% of test animals/cells. A direct measure of virulence. Legionellosis Infection with Legionella pneumophila. The bacteria colonise cooling towers, creeks, showerheads, air conditioning units, etc., and are inhaled after becoming airborne. Some patients develop pneumonia. Leishmaniasis Disease caused by protozoa of genus Leishmania, e.g. cutaneous leishmaniasis (Delhi boil, etc.) or generalised leish- maniasis (kala-azar). Leucocytes Circulating white blood cells. There are about 9000 mm -3 in human blood, divided into granulocytes (polymorphs 68-70%, eosinophils 3%, basophils 0.5%) and rnononuclear cells (rnonocytes 4%, lymphocytes 23-25%). LCM Lymphocytic choriomeningitis virus. Naturally occurring virus infection of mice displaying many phenomena of great biological interest, e.g. vertical transmission, imrnunopathology, noncytopathic infection of cells. Lymphokine A cytokine released by primed lymphocyte on contact with specific antigen. Involved in signalling between immune cells. Important in CMI; cf. monokine (e.g. IL-1) produced by monocytes and macrophages. Lysosome Cytoplasmic sac present in many cells, bounded by a lipoprotein membrane and containing various enzymes. Plays an important part in intracellular digestion. Glossary 433 Lysozyme An enzyme present in the granules of polymorphs, in macrophages, in tears, mucus, saliva and semen. It lyses certain bacteria, especially Gram-positive cocci, splitting the muramic acid- ~-(l~4)-N-acetylglucosamine linkage in the bacterial cell wall. It potentiates the action of complement on these bacteria. Presumably lysozyme is not exclusively an antibacterial substance because large amounts are present in cartilage. It is present in glandular cells in the small intestine, especially in the Brazilian ant bear, where its chitinase-like activity may help with the digestion of insect skele- tons. Marek's disease virus A herpes virus, commonly infecting chickens, and causing lymphocyte infiltration of nerves with demyelination and paralysis, and lymphoid tumours. Infectious virus present in oral secretions and feather follicles. Controlled successfully by a live virus vaccine. Memory cells Sensitised cells generated during an immune response, and surviving in large enough numbers to give an acceler- ated immune response on challenge. MHC (major histocompatibility complex) A region of the genome coding for immunologically important molecules. Class I MHC molecules are HLA (human leucocyte antigen A, B, C) in man and H2 (K, D, L) in mice. They are associated with ~2 microglobulin and expressed on the surface of nearly all cells. They confer uniqueness on the cells of each individual and ideally the class I characteristics of donor and recipient should be matched for successful organ transplantation. Class II MHC molecules (HLA-DP, DQ, DR in man; H-2 IA, IE in mice) are present on antigen-presenting cells (some macrophages, dendritic cells, Langerhans cells). Monoclonal antibody A given B cell makes antibody of a certain class, avidity and specificity. Serum antibody consists of the separate contributions from tens of thousands of B cells. Dr Caesar Milstein discovered how to induce an individual B cell to divide and form a large enough population (clone) of cells to give bulk quantities of the unique antibody. This is a monoclonal antibody. Natural antibodies Antibodies present in normal serum, reacting with a wide range of organisms. To a large extent they reflect specific responses to previous subclinical infections, e.g. normal sera lyse many Gram-negative bacteria because of antibodies induced by the normal intestinal flora. Nosocomial infection An infection acquired in hospital. Nucleocapsid Viral nucleic acid enclosed in a capsid consisting of repeating protein subunits. Opsonin (Greek opson, a seasoning or sauce). Serum component that combines with antigen or the surface of a microorganism and promotes its phagocytosis by polymorphs or macrophages. Otitis media Infection and inflammation of the middle ear. 434 Mires' Pathogenesis of Infectious Disease Passive immunity Transfer of preformed antibodies to nonimmune individual by means of blood, serum components, etc., e.g. maternal antibodies transferred to foetus via placenta or milk, or immunoglobulins injected to prevent or modify infections. Pathogenic Producing disease or pathological changes. Persistent infection An infection in which the microorganism persists in the body, not necessarily in a fully infectious form, but often for long periods or throughout life. Phage typing Different strains of Salmonella typhi, Staphylococcus aureus, or Mycobacterium tuberculosis can be distinguished on the basis of their different susceptibility to a battery of bacteriophages. Pili (see Fimbriae). Plaque forming cells (p.f.c.) Refers to lymphocytes that form areas of lysis in a layer of erythrocytes to which the lymphocytes are immunologically sensitised. Plaque forming units (p.f.u.) Refers to virus that kills cells and forms plaques (holes) in cell sheets. Plasma cell B cell which has differentiated to form rough surfaced (ribosome studded) endoplasmic reticulum, with basophilic cyto- plasm. It is the major antibody-producing cell. Plasmid A small extrachromosomal piece of genetic material in bacterium, replicating autonomously in the cytoplasm. It may carry 50-100 genes. Plasmids are common in Gram-negative bacilli, and also occur in staphylococci. Pleural and peritoneal cavities Potential cavities surrounding organs of thorax and abdomen. Lined by 'mesothelial' membrane and containing macrophages and other cells. Pneumocystis carinii Exceedingly common fungal parasite of respiratory tract of man and various animals; normally of zero pathogenicity. Little is known of its structure, life cycle or epidemi- ology. It attaches to host cells in vitro by means of a tubular projec- tion but does not enter the cell except when phagocytosed, e.g. by an alveolar macrophage. It causes pneumonia in immunocompromised individuals, either by reinfecting them or by being reactivated from a persistent state. Polyclonal activator Something that activates many clones of lymphocytes. Infections that activate B cells in this way cause the formation of large amounts of circulating antibody directed against unknown antigens as well as against the infectious agent, and often against host tissue antigens. Primary infection The first infection with a given microorganism. Primed Exposed to antigen for the first time to give a primary immune response. Further contact with the same antigen leads to a secondary immune response. Priori Infectious particle containing neither DNA nor RNA, consisting of host protein (Pr c) that has been converted into a self- replicating form (prSC). Thought to be the infectious particle causing Glossary 435 scrapie, kuru, Creuztfeld-Jakob disease (CJD), bovine spongiform encephalopathy (BSE), etc. Properdin system Consists of Factor A (a serum protein). Factor B (a ~-glycoprotein) and properdin. Not completely defined and role not understood, but may have antibacterial and antiviral action. It is an alternative pathway for the activation of complement, in which C1, C2 and C4 are short-circuited. Pyogenic Causing production of pus. Pyrogen A substance causing fever. Reservoir Animal (bird, mammal, mosquito, etc.) or animals in which a microorganism maintains itself independently of human infection. Reticulocytosis Presence in blood of increased numbers of an early form of red cell (reticulocyte), due to increased rate of production in bone marrow. Reticuloendothelial system A system of cells that take up parti- cles and certain dyes injected into the body. Comprises Kupffer cells of liver, tissue histiocytes, monocytes, and the lymph node, splenic, alveolar, peritoneal and pleural macrophages. Schistosomiasis (= bilharzia) A disease with urinary symptoms common in many parts of Africa. Caused by the fluke (trematode) Schistosoma haematobium; larvae from infected snails enter water and penetrate human skin. Shedding The liberation of microorganisms from the infected host. SSPE (subacute sclerosing panencephalitis) A rare complica- tion of infection with measles virus, occurring in about I per 100 000 cases. The incubation period of about 10 years classifies it as a 'slow' virus infection. Noninfectious mutant virus slowly spreads through the brain causing deterioration of brain function and death. Streptococci Classified into groups A-H by antigenic properties of carbohydrate extracted from cell wall. Important human pathogens belong mostly to Group A (= Streptococcus pyogenes), which is divided into 47 types according to antigenic properties of M protein present on outermost surface of bacteria. Streptolysin O Exotoxin produced by Streptococcus pyogenes. Oxygen labile, haemolytic and a powerful antigen. Streptolysin S Exotoxin produced by Streptococcus pyogenes. Oxygen-stable, causing ~ haemolysis on blood agar plates, but not demonstrably antigenic. Stress Physical or mental disturbance severe enough to initiate a coordinated response originating in the cortex and hypothalamus, and involving either the autonomic nervous system or pituitary- adrenal axis. Catecholamines and corticosteroids are released in an attempt to counter the harmful systemic effects of the disturbance (or often the threatened disturbance in the case of mental stress). Symbiotic Living in a mutually beneficial association with the host. Systemic infection Infection that spreads throughout the body. 436 Mims' Pathogenesis of Infectious Disease T cells (T lymphocytes) Population of lymphoid cells whose devel- opment depends on the presence of the thymus. Responsible for cell- mediated immunity. Compose 75% circulating lymphocytes in man. Distinguished by having on their surface CD4 proteins or CD8 proteins which define their reactivity with cells bearing MHC I or II proteins, respectively. All helper T cells are CD4. Teleology Doctrine that biological phenomena generally have a purpose, serving some function. T-independent antigen Antigen that directly stimulates a B cell to form antibody without the need for a helper T cell. These antigens (e.g. polysaccharides) have repeated determinants that cross-link Ig receptors on B cells. The antibodies formed are mostly IgM. Titre (1) A measure of units of antibody per unit volume of serum, usually quoted as a reciprocal of the last serum dilution giving anti- body-mediated reaction, e.g. 120. (2) Measure of units of virus per unit volume of fluid or tissue. Usually given in log10 units per ml or g, e.g. 105.5 p.f.u, m1-1. TNF (tumour necrosis factor) A cytokine, first recognised as a product of activated macrophages (see Table 6.1). Plays a role in disease production as well as in host defence. Toxoid Toxin rendered harmless but still capable of acting as antigen. Toxoplasma gondii A protozoan parasite of the intestine of cats, which also infects mice, humans, sheep and other animals. Humans ingest oocysts, originating from cat faeces or cysts from infected meat, and about half of the inhabitants of the UK eventually develop antibodies. It is generally asymptomatic, but disease (toxoplasmosis) sometimes occurs, and infection during pregnancy can result in congenital abnormalities involving the brain and eyes. Transfer factor A preparation derived from disrupted human leucocytes which on transfer to other individuals can supply certain missing CMI responses. The active constituent is unidentified, but it has been successfully used to treat chronic mucocutaneous candidi- asis. Transformation A change in the behaviour of a cell, for instance after infection with an oncogenic virus, so that it acquires the prop- erties of a cancer cell. Transformed cells undergo continued mitosis so that the cells in a monolayer are not inhibited from growth by contact with neighbouring cells, and continue to multiply and form a heap of cells. The word also refers to changes in a lymphocyte associ- ated with onset of division. Tuberculin test A skin test for delayed hypersensitivity to antigens from Mycobacterium tuberculosis. In man the antigen is introduced into the skin by intradermal injections (Mantoux test) or by multiple puncture (Heaf test and tine test). Vector As used in this book the word refers to an arthropod that carries and transfers an infectious agent. Quite separately, a vector [...]... virus infection 108 see also Macrophage; Natural killer (NK) cells; Polymorphonuclear leucocytes Phagocytosis 80, 85, 165 activation of macrophage 174 avoidance, microbial strategies 9 7-1 09 escape from phagosome 107 inhibition of adsorption to cell surface 10 1-2 462 Mims' Pathogenesis of Infectious Disease Phagocytosis contd avoidance, microbial strategies -contd inhibition of chemotaxis 9 9-1 01 lysosome... 19 7-2 00 local interference with immune forces 20 1-5 microorganisms in inaccessible sites 19 6-7 molecular mimicry 18 7-9 see a l s o Molecular mimicry non-induction of immune response 21 1-1 4 phagocyte interference 9 7-1 09, 105 see a l s o Phagocytosis reduced interferon response/induction 20 5-6 of Infectious Disease Immune evasion m e c h a n i s m s - - - c o n t d reduced MHC class I expression (virusinduced)... tolerance 18 4-9 0 antigens 18 4-5 autoimmune disease and 190 definition 184 desensitisation of immune cells 18 6-7 , 192, 20 0-1 453 Immunological t o l e r a n c e - - - c o n t d induction 18 4-9 0 molecular mimicry 18 7-9 prenatal infection 18 5-6 self-antigens 185, 185n see a l s o Persistence of infection Immunopathology 27 7-9 0 reactions 27 9-9 0 type 1 (anaphylactic) 279, 28 0-1 type 2 (cytolytic/cytotoxic)... vasculitis 28 2-6 systemic 28 7-8 Immune evasion mechanisms 7, 124, 18 3-2 15 absence of suitable target 19 4-6 antigenic variation 20 6-1 1 antigen-specific interference 18 5-6 completed infection before immune response 184 desensitisation of immune cells by antigens 18 6-7 immunosuppression 19 0-3 induction of inappropriate antibody response 19 7-2 00 induction of inappropriate T-cell responses 19 7-2 00 local interference... lysosome fusion inhibition 106 phagocytosis inhibition 10 2-5 , 202 resistance to killing 10 7-9 cell biology 8 5-7 of common cold viruses 25 defects 11 5-1 6 disposal of organisms after 97 downstream effectors 87, 89 epithelial cells 28 Fc-mediated 173 gastro-intestinal tract 28 killing of microorganisms 9 1-3 defective 11 5-1 6 Kupffer cells 132 in macrophages see Macrophage of noninfectious microbes 98 opsonisation... host's 280 440 Mires' Pathogenesis o f Infectious Disease Antigen(s) contd soluble 20 0-1 release 200 T-cell-independent 162, 410 tolerance induction 18 4-5 , 186, 192 in vaccines 40 9-1 0 Attenuation 40 0-1 ,401 microorganisms as carriers of vaccines 41 2-1 4 Autoimmunity 190 to vaccines 407 Axons, microorganisms spread via 14 6-7 see also entries beginning antigenic; Immune response Antigen-antibody complexes... induction/responsiveness 20 5-6 role in recovery of infections 32 4-7 therapeutic potential 32 6-7 types 205, 32 4-5 viruses interfering with 327 Interleukin-1 (IL-1), fever pathogenesis 32 9-3 0 Interleukin-6 (IL-6), fever pathogenesis 329n Interleukin-12 (IL-12) 313 Interleukins 153, 155 in acute phase response 78 Interneurons, clostridial toxin action 261 Intestinal lavage 161 Intestinal tract see Gastro-intestinal tract... motif 245 17-Ketosteroids, urinary 382 Kidney, immune complex deposition 28 2-3 , 284 Killer (K) cells 281 Killing of infected host cells 31 6-1 7 see also Cytolysis Killing of microorganisms 9 1-3 complement role 178 cytotoxic T cell action 16 9-7 0, 31 6-1 7 defective mechanisms 11 5-1 6 by macrophage 95, 317 by natural killer cells 317 by neutrophils 9 1-3 , 317 oxygen-dependent 9 1-2 oxygen-independent 9 2-3 resistance... 26 5-6 Clostridium difficile 30 opportunistic infection 52 toxins 101 ,26 3-4 toxins A and B 229, 263, 264 Clostridium novyi type B 265 Clostridium novyi type D 265 Clostridium perfringens 23 1-3 anaerobe 387 phagocytosis evasion 99, 10 0-1 toxins 10 0-1 , 26 4-5 a-toxin 23 1-3 ~-toxin 264 0 toxin 23 4-5 Clostridium perfringens type A 265 Clostridium perfringens type B 265 Clostridium perfringens type C 26 4-5 ,... transmission 6 0-2 , 61 vaccine 37 3-4 see also Neisseria gonorrhoeae G proteins 89 450 Mims' Pathogenesis of Infectious Disease Gram-negative bacteria bacilli 41 7-1 8 cell wall 94, 104 , 203, 26 7-8 immune evasion mechanism 203 cocci 417 endotoxins see Endotoxin secretion systems 32 smooth and rough colonies 203, 271, 366 Gram-positive bacteria bacilli 417 cell wall 94 cocci 417 SH-activated cytolysins 23 3-6 Granulation . 20 4-5 , 316 similar to host's 280 440 Mires' Pathogenesis of Infectious Disease Antigen(s) contd soluble 20 0-1 release 200 T-cell-independent 162, 410 tolerance induction 18 4-5 ,. novyi type D 265 Clostridium perfringens 23 1-3 anaerobe 387 phagocytosis evasion 99, 10 0-1 toxins 10 0-1 , 26 4-5 a-toxin 23 1-3 ~-toxin 264 0 toxin 23 4-5 Clostridium perfringens type A 265 Clostridium. Brill's disease 347 Brill-Zinsser disease 347 Bronchitis 385 chronic 333 442 Mims& apos; Pathogenesis of Infectious Disease Brucella 418 foetal infection 141, 142 growth in macrophages 72, 108 ,