Thelma C. Fletcher

PHYLOGENETIC ASPECTS OF C-REACTIVE PROTEIN AND RELATED PROTEINS*

C-reactive protein (CRP) was discovered by Tillett and Francis’ in the sera of patients with various infectious and inflammatory diseases as a material which precipitated pneumococcal C-polysaccharide (CPS). Subsequently Abernethy and Ave

The effect of stress on the immune response of Atlantic salmon (Salmo salar L.) fed diets containing different amounts of vitamin C

characterized CRP as a protein and identified the requirement for calcium ions in its interaction with CPS, while they and established that the appearance of CRP in the serum is a nonspecific response to infection, inflammation and tissue damage. Abernethy and Averf also introduced the term “acute phase sera” to designate samples obtained from patients in the acute phase of infectious diseases. CRP was called the “acute phase protein” and this term was subsequently applied to the large number of other plasma proteins, the concentrations of which are raised in acute phase sera. At an early stage Abernethy’ reported the presence of a precipitin comparable to CRP in acute phase monkey serum and, although he had been unable to find any in mouse or rabbit sera, Anderson and McCarty’later described the existence

PHAGOCYTOSIS IN FISH

An experiment was performed to determine the effects of dietary vitamin C levels and stress on immunological parameters in Atlantic salmon (Salmo salar L.). Atlantic salmon parr were maintained on diets containing 0.082 (low), 0.44 (normal) and 3.17 (high) g vitamin C/kg dry diet. After 23 weeks, tissue levels were found to reflect dietary input. Groups of fish were removed and subjected to a 2 h confinement stress prior to sacrifice and isolation of plasma and head kidney leucocytes. Leucocyte respiratory burst activity (P<0.01) and bactericidal activity (P<0.05) were both found to be significantly reduced by stress, but were unaffected by vitamin C status. Leucocyte migration was unaffected by stress or vitamin C status. Plasma bactericidal activity was also unaffected by vitamin C status but was significantly enhanced by stress (P<0.05). Production of specific antibody following immunisation with Aeromonas salmonicida was found to be significantly reduced (P<0.01) by stress, and there were significantly greater levels of specific antibody (P<0.01) in fish fed the low vitamin C diet compared with fish fed high levels of vitamin C.

Effect of temperature on macrophage activation and the production of macrophage activating factor by rainbow trout (Oncorhynchus mykiss) leucocytes.

Publisher Summary This chapter discusses phagocytosis in fish. Phagocytosis, the cellular ingestion and digestion of particulate matter, is probably the most widely distributed defense reaction occurring in virtually all animal phyla, As shown by primitive organisms, the process is directly related to nutrition and defense, but with the appearance of metazoan organization, cells specifically dedicated to the recognition and elimination of nonself material emerged. The presence of a vascular system also enhanced the speed with which these phagocytic cells could be mobilized at sites of injury, to dispose of invading bacteria and damaged cells from the organism itself. The phagocytic cells that play an important role in vertebrate defense mechanisms fall into two categories: (1) the granulocytes and (2) the mononuclear phagocytes. The phagocytic cells of fish can be generally considered within these groups. Studies on the behavior of phagocytic cells in fish exposed to pathogens can provide information on their effectiveness as defensive cells. A defect in phagocyte recognition, ingestion, or intracellular killing could be a contributory factor in the pathogenicity of some organisms.

C-reactive protein and serum amyloid P component in the plaice (Pleuronectes platessa L.), a marine teleost, are homologous with their human counterparts

Production of macrophage activating factor (MAF) by rainbow trout leucocytes has been shown to be temperature dependent in vivo and in vitro. Cells from fish held at 14 degrees C and stimulated to produce MAF immediately after isolation were capable of secreting MAF down to 6 degrees C (the lowest temperature tested). However, after 48 h at 6 degrees C, these leucocytes show impaired MAF secretion. Acclimation of fish to low temperatures (7 degrees C) did not recover the inhibitory effects of low in vitro temperatures on MAF production, but if these leucocytes were preincubated at 10 or 18 degrees C for 48 h, MAF was produced from these cells. Interestingly, macrophages isolated from fish kept at 7 or 14 degrees C and cultured at low temperatures (6 degrees C) were responsive to MAF-containing supernatants, and showed a higher relative increase in respiratory burst activity compared with their counterparts cultured at 10 and 18 degrees C. Such observations clearly demonstrate that a major impairment of bactericidal activity at low temperatures resides within the specific immune compartment of fish. The implications for fish health are discussed.

The effect of dietary vitamin A on the immunocompetence of Atlantic salmon (Salmo salar L.).

C-reactive protein and serum amyloid P component were isolated from serum of the plaice (Pleuronectes platessa L.), a murine teleost. The isolation was based on their calcium-dependent binding affinity for pneumococcal C-polysaccharide and for agarose, respectively. These specificities are the same as those of human C-reactive protein and serum amyloid P component, respectively, and we have previously reported that the plaice molecules resemble human C-reactive protein and serum amyloid P component in their electron microscopic appearance. We describe here estimation of the molecular weights of plaice C-reactive protein and serum amyloid P component and their subunits, and analysis of their amino acid composition, glycosylation and partial amino-terminal amino acid sequences. The results establish that plaice C-reactive protein and serum amyloid P component are homologous with each other and with their human counterparts and indicate that there has been stable conservation of this protein family throughout vertebrate evolution.

The effect of inflammatory agents on C-reactive protein and serum amyloid P-component levels in plaice (pleuronectes platessa L.) serum

Atlantic salmon, Salmo salar L. were maintained on diets containing low (0.37 mg kg−1 diet), normal (1.95 mg kg−1 diet) and high (15 mg kg−1 diet) levels of vitamin A fed at 1.5% body weight per day. After 4 months, liver vitamin A levels reflected dietary intake and growth rates of all three groups were similar. Kidney leucocyte migration and serum bactericidal activity were found to be significantly reduced in fish fed low levels of vitamin A. On the other hand, high levels of vitamin A in the diet were found to augment serum antiprotease activity relative to the levels found in the other dietary groups. However, phagocyte respiratory burst activity, bactericidal activity and eicosanoid production were unaffected by the dietary vitamin A regime, as were lymphocyte functions (lymphokine and antibody production) and both serum lysozyme and classical complement activity. That the overall immunomodulatory effect of vitamin A was small was reflected in the resistance to Aeromonas salmonicida. No significant differences were found between the different vitamin A intake groups despite a trend to decreased resistance in the low vitamin A diet group.

IMMUNOCOMPETENCE AS A MEASURE OF THE BIOLOGICAL EFFECTS OF SEWAGE SLUDGE POLLUTION IN FISH

1. 1. Bacterial lipopolysaccharide, Freunds complete adjuvant, turpentine, carrageenan or etiocholanolone were injected into groups of plaice maintained at 11–12°C. 2. 2. Serum amyloid P-component (SAP), C-reactive protein (CRP) and total protein concentrations were measured in the serum over the 25-day period following injection. 3. 3. Lipopolysaccharide caused a significant increase (P < 0.01) of CRP within 24 hr and carrageenan (P < 0.001) within 4 days, although SAP and protein declined. 4. 4. The other irritants caused a steady decrease in the serum proteins.

The lysozyme of the plaice Pleuronectes platessa L.

1. Dab, Limanda limanda, exposed to nominal concentrations of 0 (control), 0.0032% (low) and 0.032% (high) sewage sludge in seawater for 12 weeks, were assessed for their immunological competence. 2. No effect upon total blood leucocyte and erythrocyte numbers was found, although significantly fewer thrombocytes were seen in the high-exposure group. 3. A decreased serum protein level was found in the high exposure group, but lysozyme and immunoglobulin levels showed non-significant differences between the groups. 4. Melano-macrophage centres were also affected in the high-exposure dab, which had increased numbers in the spleen and kidney. No effect upon spleen weights or oxygen free radical production by splenocytes was noted. However, oxygen free radical production by kidney leucocytes was inhibited in the low-exposure dab.

Serum cortisol, glucose and lipids in plaice (Pleuronectes platessa L.) exposed to starvation and aquarium stress

Abstract Lysozyme from the serum of the plaice, Pleuronectes platessa L., has been purified 78-fold with chitin coated cellulose. 1. 2. Further purification on CM-cellulose yielded a single band on acrylamide electrophoresis, exhibiting lysozyme activity. 2. 3. The quantitative amino acid composition of plaice serum lysozyme is reported. 3. 4. The mol. wt is identical with hen egg white lysozyme. 4. 5. A method is described for identifying fractions with lysozyme activity in polyacrylamide gels.