Serum concentrations of IgG, IgA, and IgM in retired racing Greyhound dogs

Background: Greyhound dogs have significant physiologic, hematologic, and biochemical differences when compared with other breeds, including significantly lower serum globulin concentration owing to decreases in the α‐ and β‐globulin fractions. The specific proteins that account for differences in globulin concentrations are not known, but IgA and IgM, both β‐globulins, are potential candidates. Objectives: The aims of this study were to measure serum IgG, IgA, and IgM in clinically healthy retired racing Greyhounds and compare the results with those of age‐ and sex‐matched non‐Greyhound dogs. Methods: Study animals included 25 Greyhound and 20 non‐Greyhound dogs. Total protein, albumin, and total globulin concentrations were determined. IgG, IgA, and IgM concentrations were measured using a commercially available radial immunodiffusion kit. The Student t‐test assuming equal variances was used to compare concentrations of immunoglobulins between groups. Results: Serum concentrations of IgA and IgM in Greyhounds (IgA=49±20 mg/dL; IgM=132±47 mg/dL) were significantly lower than concentrations in non‐Greyound dogs (IgA=70±39 mg/dL; Ig M=212±78 mg/dL). Concentrations of IgG did not differ between groups. Conclusions: Mean serum IgA and IgM concentrations in Greyhounds were lower than those in non‐Greyhound dogs. This may contribute to low serum concentrations of β‐globulins in Greyhounds. Specific reference intervals are recommended for Greyhounds to avoid possible misdiagnosis of IgA or IgM deficiency.     

Serum concentrations of immunoglobulins G, A, and M in dogs with neoplastic disease

The concentrations of the three major classes of immunoglobulins (Ig) were determined in canine serum by single radial immunodiffusion against calibrated standards. Serum samples were collected from 121 dogs categorized into 3 groups: normal dogs (n = 34), those with lymphosarcoma (n =41), and those with malignant, solid neoplasms other than lymphosarcoma (n = 46). The mean value for serum IgM concentration in the group of dogs with lymphosarcoma was significantly (P less than or equal to 0.02) higher than was the mean IgM concentration of the normal dogs. Dogs with neoplasms other than lymphosarcoma had significantly increased serum concentrations of IgG and IgM antibodies. There was no significant difference in serum IgA concentration among the three groups. A wide range of Ig concentrations was in the serum of clinically normal dogs, as well as in dogs with neoplastic diseases. Although individual dogs with neoplasms had low serum Ig concentrations, the 81 dogs with neoplastic disease were generally able to synthesize Ig.     

Profile of anti-Leishmania antibodies related to clinical picture in canine visceral leishmaniasis

This research investigated the profile of anti-Leishmania antibodies in different clinical forms of canine visceral leishmaniasis (CVL). Naturally infected dogs were divided into two groups: subclinical dogs (SD, n=10) and clinical dogs (CD, n=68). Non-infected dogs (ND, n=7) comprised the negative control group. The humoral response was evaluated by the profile of total IgG, IgG1, IgG2, IgM, IgA and IgE, determined by ELISA. Infected animals showed increased levels of total IgG, IgA and IgE in addition to IgG1 and IgG2 in groups SD and CD, when compared with group ND. Furthermore, it was observed that IgG2 and IgM were correlated with symptomatology, while total IgG, IgG1 and IgA were negatively correlated and IgE showed no correlation. It follows that serum levels of IgG2 anti-Leishmania are correlated with typical clinical signs of disease. Furthermore the determination of specific anti-Leishmania antibodies could be an important tool in monitoring CVL clinical picture.     

Immunopathogenesis of canine angistrongylosis: pulmonary effects of infection

Deposits of immunoglobulins, complement, and fibrinogen were localized in the lungs of Angiostrongylus vasorum-infected dogs. In acutely infected dogs, significant deposits of IgA, IgG and IgM, complement, and fibrinogen were seen. The predominant immunoglobulin noted in infections of longer duration was IgG. The continued presence of fibrinogen as the predominant protein deposited suggested a continuation of intravascular coagulation. This was borne out by demonstrating luminal deposits of fibrinogen in many blood vessels. Histopathologic examination of the large revealed lesions typical of angiostrongylosis, as well as eggs of the worm as early as 35 days postinfection. This is the earliest report of egg production by A. vasorum on record.     

Survey of serum IgA, IgG, and IgM concentrations in a large beagle population in which IgA deficiency had been identified

Concentrations of serum IgA, IgG, and IgM were determined for 829 adult Beagles from a commercial kennel in which several IgA-deficient dogs had been identified previously (index kennel). These values were compared with measurements of 100 adult dogs from another Beagle kennel (control kennel). After adjustment for differences in the ages and gender of the dogs, dogs from the index kennel had significantly (P less than 0.0001) lower IgA concentrations (mean, 46 mg/dl) than dogs from the control kennel (mean, 68 mg/dl). Regardless of kennel, males had significantly (P less than 0.01) higher IgA concentrations than did females. Dogs in the control kennel had significantly (P less than 0.04) higher IgG concentrations (mean, 2,649 mg/dl) than did dogs in the index kennel (mean, 2,478 mg/dl), and female dogs in the control kennel had significantly (P less than 0.05) higher IgM concentrations (mean, 189 mg/dl) than dogs of either sex in the index kennel (mean, 162 mg/dl) or male dogs in the control kennel (mean, 163 mg/dl). For both sexes, concentrations of IgA, IgG, and IgM increased with age.     

Normal profile of immunoglobulins in sera and tracheal washings of chickens

Concentration and distribution of the three immunoglobulins in the sera and tracheal washings of a chicken population was studied. The mean IgM, IgG and IgA concentrations in serum were 1.35, 5.09 and 0.31 mg/ml, respectively. The distribution of IgM and IgG in birds irrespective of age was almost normal whereas that of IgA was skewed. All the three immunoglobulins were present in tracheal washings but the level of IgM was barely detectable. The IgG was predominant in the tracheal washings but higher IgA : IgG ratio compared to that of serum indicated local IgA production in the chicken respiratory tract.     

Isolation and phenotypic and functional characterization of cells from Peyer's patches in the dog.

Cells were isolated from canine Peyer's patches (PPs) and their phenotype and capacity to secrete immunoglobulins in vitro were determined. Cells isolated from duodenal and jejunal PPs of adult dogs consisted of 91.4% lymphocytes and 1.6% macrophages with 55.4% mIg(+)-cells and 35.6% Thy-1(+)-cells. In vitro IgA secretion by pokeweed mitogen (PWM)-stimulated PP cells exceeded that by cells from other lymphoid tissues and was specifically increased by concanavalin A, suggesting a role for isotype-specific T-cells. Comparison of duodenal and jejunal (proximal) PPs and the ileal PP revealed that the ileal PP contained fewer T-cells, fewer mIgA(+)-cells and more mIgM(+)-cells. Cells from the ileal PP produced very little IgA and IgG, but abundant IgM in vitro. These data suggest that the proximal PPs of dogs are important in the generation of IgA B-cells, similar to PPs of rodents. The ileal PP of dogs may have a function in the early development of the B-cell system of the dog.     

Pitfalls in immunofluorescence testing in canine dermatology

Indirect immunofluorescence testing for pemphigus-like antibodies was performed on 100 dogs: 50 dogs with various nonpemphigus dermatologic diseases, 25 dogs with various nondermatologic diseases, and 25 normal dogs. One dog (generalized demodicosis) was positive for pemphigus-like antibodies at a titer of 1:10. It was concluded that canine pemphigus-like antibodies are a potential source of misinterpretation and misdiagnosis in indirect immunofluorescence testing. Direct immunofluorescence testing for IgG, IgA, IgM, and C3 was performed on the footpads of 11 normal dogs. Granular deposition of IgM at the basement membrane zone was demonstrated in 5 of the 11 dogs. It was concluded that direct immunofluorescence testing of canine footpads using only polyvalent immunoglobulin antisera or anti-IgM antisera may lead to misinterpretation and misdiagnosis in up to 45% of all dogs tested.     

Immunoglobulin class response to canine distemper virus in gnotobiotic dogs

Serial serum samples from 27 gnotobiotic dogs infected with R252-canine distemper virus (CDV) were tested for anti-viral IgG, IgM and IgA immunoglobulins using an enzyme-linked immunosorbent assay (ELISA). The results were compared retrospectively to clinicopathological course of disease and to previously reported patterns of complement-fixing and virus neutralizing antibody titers determined in these same sera. Virus-specific IgA was never detected in the sera. High levels of IgG correlated with recovery from disease, whereas the antiviral IgM levels were equivalent in both persistently infected animals and those animals which recovered from disease. The inability to sustain a significant antiviral antibody response in either IgM or IgG classes was characteristic of dogs with fatal encephalitis. The data suggests that IgG is the most important Ig class for recovery from disease.     

The humoral immune response to recombinant nucleocapsid antigen of canine distemper virus in dogs vaccinated with attenuated distemper virus or DNA encoding the nucleocapsid of wild-type virus

This study compared the humoral immune response against the nucleocapsid-(N) protein of canine distemper virus (CDV) of dogs vaccinated with a multivalent vaccine against parvo-, adeno-, and parainfluenza virus and leptospira combined with either the attenuated CDV Onderstepoort strain (n = 15) or an expression plasmid containing the N-gene of CDV (n = 30). The vaccinations were applied intramuscularly three times at 2-week intervals beginning at the age of 6 weeks. None of the pre-immune sera recognized the recombinant N-protein, confirming the lack of maternal antibodies at this age. Immunization with DNA vaccine for CDV resulted in positive serum N-specific IgG response. However, their IgG (and IgA) titres were lower than those of CDV-vaccinated dogs. Likewise, DNA-vaccinated dogs did not show an IgM peak. There was no increase in N-specific serum IgE titres in either group. Serum titres to the other multivalent vaccine components were similar in both groups.     

Dynamics of Leishmania-specific immunoglobulin isotypes in dogs with clinical leishmaniasis before and after treatment

Concentrations of Leishmania-specific immunoglobulin G (IgG), immunoglobulin M (IgM), and immunoglobulin A (IgA) isotypes were analyzed by enzyme-linked immunosorbent assay (ELISA) in 23 dogs naturally infected with Leishmania infantum before and 1 year after initiating drug therapy. Results showed a high expression and prevalence of Leishmania-specific IgG (176.4 +/- 89 ELISA units [EU]), IgM (105.3 +/- 95.5 EU), and IgA (153.6 +/- 98 EU) in dogs before treatment (median +/- interquartile range EU). One year after treatment was started, dogs were classified as responsive dogs (RDs; n = 13) or unresponsive dogs (UDs; n = 10) based on clinicopathologic findings. Both groups of dogs experienced a statistically significant decrease (P < .05) in Leishmania-specific IgG (RDs = 27%, UDs = 41%), IgM (RDs = 42%, UDs = 29%), and IgA (RDs = 56%, UDs = 46%). Concentrations of specific IgG and IgM were not different at diagnosis or after treatment between the 2 groups. However, the median value for Leishmania-specific IgA 1 year after treatment was significantly lower (P < .05) in RDs (60.8 +/- 67 EU) than in UDs (117 +/- 54 EU). Examination of our data indicates that both the IgA isotype, which is mostly produced by mucosal plasma cells, and the IgM isotype are increased in infected symptomatic dogs, as previously reported for IgG. These 3 isotypes decreased significantly 1 year after initiation of medical treatment.     

IgA, igG1, IgG2, IgM, and BSA in serum and mammary secretion throughout lactation

Bovine IgG1, IgG2, IgA, and IgM were measured in the serum and lacteal secretions of six cows from 10 days prepartum to 240 days of lactation. Immunoglobulins in lacteal secretions were expressed in units of concentration (mg/ml) as well as in total daily output. All isotypes were selectively accumulated during colostrum formation. The rate of IgG1 accumulation decreased rapidly after calving; this decrease corresponded to a return to normal serum levels of this immunoglobulin. Selective accumulation of IgA > IgM > IgG1 was maintained throughout lactation, but IgG2 showed no selective accumulation beyond 5 days postpartum. In serum, IgA and IgM levels were elevated at parturition and showed a significant decrease postpartum. Increases in serum IgA levels 60 days postpartum corresponded to a rise in lacteal concentration. The concentration of all immunoglobulins increased during late lactation, coincident with a major reduction in milk yield. Six strains of mastitis-causing organisms were cultured during the period of the experiment; however, none resulted in clinical mastitis or showed an effect on immunoglobulin secretion.     

Quantitative aspects of binding of canine serum immunoglobulins of Staphylococcus aureus protein A

Quantitative interactions of Staphylococcus aureus protein A (SPA) and canine immunoglobulins (Ig) are described. The S aureus Cowan strain I bound canine IgG, IgM, and IgA, whereas binding was not observed with the SPA-negative Wood 46 strain of S aureus. In a quantitative adsorption experiment, the results indicated that IgA, though present in the lowest amounts in the samples, appeared to be substantially bound by SPA. Adsorption of sera with SPA-negative Wood strain bacteria resulted in nonspecific protein losses in supernatants of 0% to 15%.     

Immunoglobulin containing cells in the tracheobronchial tree of cattle: relationship to age

The cells of the pulmonary immune system of cattle were examined using an immunoperoxidase technique to identify cytoplasmic immunoglobulins. Cells reacting immunohistochemically with bovine IgG1, IgG2, IgA and IgM antisera were quantified in formalin-fixed paraffin embedded tissues from systematically selected sites within the tracheobronchial tree. Non-pneumonic lungs were selected for study from five groups of cattle which ranged in age from neonatal calves to aged adult cattle. Age associated differences were found. Neonatal calves lacked immunoglobulin containing cells (ICC). The numbers of ICC in 18-month-old cattle were significantly greater than in other age groups. The relative frequency of each immunoglobulin class among the cells of the airway mucosa was IgA greater than IgG1 greater than IgG2 greater than IgM for all cattle four months and older (n = 20) with an IgA to IgG1 ratio of 3.46. All airway categories from trachea to bronchiole had similar proportions of cells in each immunoglobulin class although the cell density declined in the distal airways.     

Humoral and cellular immune responses in dogs with inapparent natural Leishmania infantum infection

Molecular analysis, serology and immunophenotyping for T lymphocytes and their subsets, B lymphocytes and monocytes were performed on dogs naturally infected with Leishmania infantum. Animals were categorised as asymptomatic dogs I (AD-I), with negative serology and positive molecular results, and asymptomatic dogs II (AD-II), with positive serology and positive molecular results, and these were compared to symptomatic dogs (SD) and control dogs (CD). AD-I exhibited immunophenotypic features similar to those of CD, including isotype profiles and concentrations of monocytes. Similar biomarkers were found in AD-II and SD, such as, higher levels of immunoglobulins IgG, IgG2, IgM and IgA and higher concentrations of eosinophils. High frequencies of T lymphocytes and CD4(+) T cells were observed in both AD-I and AD-II compared to SD, whereas CD8(+) T cells were higher only in AD-II compared with SD. Analysis of B lymphocytes revealed an increased frequency of this cell type only in AD-II animals compared with SD. Asymptomatic dogs appear to have a dichotomous infection spectrum that can influence the humoral and cellular immunological status during canine visceral leishmaniasis.     

The differential localization of IgA,IgM and IgG in the gut of suckled neonatal piglets

The localization of immunoglobulins IgG, IgM and IgA in tissue sections prepared from the ileum of neonatal and adult swine were compared. Eighty percent of the immunoglobulin-containing lymphoid cells in the lamina propria of conventional adult German Landrasse swine were IgA-positive with lower numbers of IgM cells and occasionally an IgG cell. Anti-μ and α-chain reagents also stained the cytoplasm of the crypt epithelial cells. By comparison to these adult control tissues, the ileum of unsuckled neonates contained no immunoglobulins although after the ingestion of colostrum, the entire cytoplasm of the villus epithelial cells stained intensely when tested for IgG with only faint staining for IgM and IgA. On the other hand, IgA and IgM were readily localized on what appears to be only the apical border of the crypt epithelial cells but in contrast to the adult, the cytoplasm of these cells was unlabelled. IgG was absent from the crypt region. We interprete these findings to indicate an important, selective role for the villus epithelium in the absorption into the neonatal circulation of colostral IgG and probably IgA and IgM, and a specialized role for the crypt epithelium in adsorbing colostral IgA and IgM; possibly by complexing with mucin-bound secretory component.     

Measurement of immunoglobulins in reproductive tract fluids of bulls

Seminal, seminal vesicular, urethral and preputial fluids from bulls of two different age groups were assessed for quantitative differences in immunoglobulins. Selected markers were measured in individual samples to differentiate locally derived immunoglobulins from those present as a result of trauma or secretions from other accessory glands.Immunoglobulin levels in reproductive tract fluids from older bulls (5–6 years) were higher than those of younger bulls (3–4 years) and preputial fluids contained the highest concentration of immunoglobulins of all fluids examined. Similarities existed, however, among all fluids in the relative concentrations of immunoglobulins. IgG was generally in highest concentration, though the predominant subclass varied. A marked predominance of IgG₂ over IgG₁ occurred in preputial fluid samples of older bulls. IgA was in second highest concentration, and levels were often equal to or greater than those in serum. IgM was in low concentration and occasionally undetectable. IgG/IgA ratios did not exceed 5 in most of the reproductive fluids, whereas serum ratios were usually over 100. Proportional contents of albumin and immunoglobulin in reproductive tract fluids by comparison with those in serum indicated that substantial quantities of IgG as well as IgA were synthesized locally or derived by selective transport. Increased numbers of plasma cells in the lamina propria of the preputial and penile mucosa of older bulls were correlated with higher immunoglobulin concentrations in preputial fluid from older bulls, suggesting that differences in local synthesis were responsible.     

Isotype determination of circulating autoantibodies in canine autoimmune subepidermal blistering dermatoses

Abstract The three most common canine autoimmune blistering skin diseases (AISBD), bullous pemphigoid (BP), mucous membrane pemphigoid (MMP) and epidermolysis bullosa acquisita (EBA) have recently been separated based on clinical, histological and immunological grounds. The objectives of this study were to determine the isotype profiles of circulating autoantibodies in these dermatoses. Serum was collected from 5 dogs with BP, 15 with MMP and 11 with EBA. All sera were tested using an indirect immunofluorescence method using salt-split canine gingiva as substrate. Anti-basement membrane IgG autoantibodies were detected in all patients. Among the IgG autoantibodies, IgG1 and IgG4 were encountered most frequently, while IgG2 and IgG3 were uncovered in some dogs. IgE autoantibodies were detected more often than IgA or IgM autoantibodies in any of the three entities. The predominance of IgG1, IgG4 and IgE autoantibody isotypes in dogs with AISBD is very similar to the situation found in humans with the homologous diseases.     

Synthesis of immunoglobulin by normal and antigenically stimulated fetal sheep.

The rate of appearance, quantity and immunochemical character of serum immunoglobulins which appear normally during the development of fetal sheep and following the injection of antigens at different stages of gestation have been studied. After 70 days' gestation a percentage of normal fetal sheep synthesise IgM. Although the concentration of IgM in the circulation of these animals was very low, the precentage with IgM increased with fetal age. A few late term fetuses were detected which also had IgG1 in their circulation, although none were detected with IgG2 or IgA. Fetuses injected with antigens before 71 days' gestation only synthesised IgM, while fetuses injected after 79 days' gestation synthesised both IgM and IgG1. Neither IgG2 nor IgA were detected by single-radial immunodiffusion analyses during the first 14 days of primary immune responses to a variety of antigens, although trace amounts of IgG2 were detected late in responses occurring in older fetuses. The immunoglobulins synthesised by antigenically stimulated fetal sheep appeared identical to adult sheep 19S IgM, 7S IgG1 and 7S IgG2 respectively, when analysed by immunoelectrophoresis, isoelectric focusing and G200 Sephadex column chromatography.     

Dynamic changes of immunoglobulin concentrations in pig colostrum and serum around parturition

The aim of the study was the determination of IgA, IgM and IgG concentrations in porcine serum and colostrum, in order to evaluate their variations in the perinatal period, as well as to clarify whether there is a correlation between colostrum intake, initial level of immunoglobulins (Ig) in piglet serum and development of their own immunity. The mean IgA, IgM and IgG concentrations in sow serum 10 days before parturition were 1.58, 6.12 and 39.56 mg/ml, respectively. Seven days later only the IgG level was insignificantly lower (34.94 mg/ml, p = 0.55), while concentrations of IgA and IgM increased to 2.25 and 7.25 mg/ml, respectively (p = 0.23 and 0.62, respectively). The mean initial IgG concentration in colostrum at farrowing was 118.5 mg/ml and differed between sows. The average value of IgA in colostrum at birth was 23.8 mg/ml and decreased to 7.85 mg/ml at 6 hours (h) and to 4.59 mg/ml at 24 h after the onset of farrowing. IgM concentration at birth was 12.1 mg/ml and decreased to 4.23 mg/ml at 24 h postpartum. Positive relationships were found between concentrations of IgM and IgA in serum of piglets at 14 and 56 days of life (r = 0.41 and 0.80, respectively, p < or = 0.05) as well as for IgG concentration in the piglets serum at 7 days and 56 days of age (r = 0.48, p < or = 0.05). The above observations suggest that there is a correlation between the level of Ig in piglet serum in the first days of life and improvement of their own immunity.