Phagocytosis. Clinical disorders of recognition and ingestion

Tentative conclusions concerning the role of recognition and ingestion of microorganisms by phagocytes in host defense and the consequences of disorders of phagocytosis can be derived by correlating a) knowledge about recognition and ingestion derived from studies in vitro, b) investigations of the clearance of particulate matter from the circulation of animals and man, and c) analyses of the behavior of phagocytes in patients susceptible to recurrent pyogenic infections. Deficiency of the major serum recognition-conferring (immunoglobulins and complement proteins that deposit a fragment of C3 on microbes) prevents the optimal clearance of virulent encapsulated pathogens by fixed mononuclear phagocytes. Confrontation of phagocytes with particulate matter appearing in pathologic states (viruses, immune complexes, damaged erythrocytes in sickle cell anemia and other hemoglobinopathies) diverts them from their normal task of clearing opsonized encapsulated microorganisms. Corticosteroids impair the phagocytic capacity by an unknown mechanism. Major impediments to progress in this field are inadequate assays for phagocytosis and the difficulty in measuring phagocytosis in the intact organism.

Antibodies to Candida albicans in IgA-deficient humans

Titers of serum antibody to Candida albicans were studied in 111 IgA-deficient subjects by the passive hemagglutination method. Circulating antibodies to C. albicans (mean titer, 1:7) were found in only 7.3% of the 111 subjects, as compared with 80% of 137 controls (mean titer, 1:16). However, two IgA-deficient patients with systemic candidiasis were positive for these antibodies (mean titer, 1:64). Indirect immunofluorescence tests indicated that the antibody response in IgA-deficient subjects to superficial or deep-seated infection with C. albicans consists mainly of immunoglobulins of the IgG rather than of the IgM class.

Opsonic requirements for staphylococcal phagocytosis. Heterogeneity among strains

Efficient phagocytosis of staphylococci by human neutrophilis is dependent on bacterial opsonization by serum factors. These factors include specific antibodies as well as components of the classical and alternative complement systems. In this study the opsonic requirements of three strains of S. aureus and three strains of S. epidermidis were investigated by incubating [3H]thymidine-labelled bacteria in sera with different opsonic activities and measuring rates of phagocytosis by human neutrophils. Opsonization of S. aureus Cowan I and 502 A depended primarily on activation of the classical complement pathway. Effective opsonization occurred in the absence of immunoglobulin but not in the absence of complement. A protein A deficient mutant of S. aureus Cowan I was poorly opsonized in the absence of IgG, however. S. aureus Wood 46 and two strains of S. epidermidis were opsonized primarily through the alternative complement pathway and depended on the presence of serum IgG. A third S. epidermidis strain was efficiently opsonized in heat-inactivated serum without complement activity. Thus, a heterogeneity of opsonic requirements was found among staphylococcal strains. It is proposed that cell wall protein A may be an important determinant of this heterogeneity.

Activation of IgE regulatory mechanisms by transmucosal absorption of antigen

The development of immediate hypersensitivities depends essentially on the production of IgE antibodies--usually to common environmental antigens. It has been suggested that atopic individuals produce IgE antibodies as a result of overstimulation with antigen and that this occurs through IgA deficiency which by default allows the absorption via the mucosae of abnormally large amounts of antigen. However, work with laboratory animals indicates a mechanism which is the antithesis of the overstimulation concept: that quantities of antigen sufficiently large to activate IgE immunoregulatory mechanisms, particularly suppressor T cells, are normally absorbed across the mucosae and that, where other conditions for the activation of these cells are appropriate, inhibition rather than stimulation of IgE responses results. In this way allergies arise through a defect of one or more components of the immunoregulatory mechanism. The fact that atopic individuals do not become allergic to all ubiquitous antigens and that they may be hyposensitised is evidence that the defect is relative rather than absolute.

Selective immunoglobulin M deficiency in foals

Selective immunoglobulin M deficiency was diagnosed in 5 foals, on the basis of reduced serum immunoglobulin M concentrations (more than 2 standard deviations below the normal mean). All 5 foals had clinical signs or lesions involving the respiratory tract. Lkebsiella sp was isolated from joint fluids, bronchial lymph nodes, or tracheal washings from the 3 foals in which such samples were available for microbiologic evaluation.

[Impairment of humoral immunity in aging]

1) Aging is associated with a hypergammaglobulinemia consistng of an increase in the serum IgG and IgA, plus a reduction in the IgM. This is associated with an increase of the B lymphocyte circulating pool, and an increase of the ratio IgG-B cells; 2) There is a reduction of the serum concentration of natural isoagglutinins. 3) The secondary IgG response against diphteria toxin (DT) is similar in 15 young and 15 old subjects. 4) There is a reduction of the IgE response against DT in old subjects.

[Evaluation of thymic hormone and E-rosettes in patients with IgA deficiency]

We have investigated lymphocyte subpopulations and T cell functions, in particular E rosettes and serum level of thymic factor in ten young patients (aged 6 to 20) with partial and selective IgA deficiency. The control group included ten age-matched healthy subjects. Significantly depressed levels of serum thymic factor were found in six patients. These results were correlated with the decreased number of E rosettes found in five of them, and support a T-cell involvement in IgA deficiency.

A syndrome of immunoglobulin A deficiency, diabetes mellitus, malabsorption, a common HLA haplotype. Immunologic and genetic studies of forty-three family members

Three persons in a kindred of 43 had variable expression of a syndrome consisting of immunoglobulin A deficiency, diabetes mellitus, malabsorption, and a common HLA haplotype. Findings from the proband included life-threatening malabsorption; idiopathic intestinal mucosal atrophy with infalmmation; IgA deficiency and antibodies to multiple endocrine organs; insulin-dependent diabetes mellitus; and the major histocomptability antigens HLA-A2, B8, and DW3. In addition to the described syndrome other conditions present in the family include Graves' disease, vitiligo, hypocomplementemia, rheumatic fever, multiple sclerosis, and a high frequency of antibodies to endocrine tissue. Since Graves' disease, diabetes mellitus, and idiopathic Addison's disease have all been described in association with HLS-B8 and DW3, we believe that the occurrence of these diseases in this family suggests that a single immune response gene or gene complex is linked with HLA-B8 and DW3.

Rosette formation with mouse erythrocytes. III. Studies in patients with primary immunodeficiency and lymphoproliferative disorders

Rosette formation with mouse erythrocytes and other cell-surface markers were examined on lymphocytes from patients with a variety of primary immunodeficiency and lymphoproliferative disorders. Mouse erythrocyte rosette-forming cells and lymphocytes with surface immunoglobulins were regularly absent in patients with Bruton type agammaglobulinaemia, immunodeficiency and thymoma syndrome and severe combined immunodeficiency disease. However, they were present in normal or low numbers in patients with common variable immunodeficiency, selective IgA deficiency and ataxis telangiectasia. Lymphocytes from patients with acute lymphoblastic leukaemia Sezary syndrome and mycosis fungoides made no or few rosettes with mouse erythrocytes. Increased numbers of mouse erythrocyte rosette-forming cells were present in patients with chronic lymphocytic leukaemia and Waldenstrom's macroglobulinaemia. The significance of the mouse erythrocyte rosette as a B-cell marker in the analysis of primary immunodeficiency and lymphoproliferative disorders is discussed.

Biological and clinical significance of the gut as a barrier to penetration of macromolecules. Practical implications with respect to breast feeding

This review stresses the importance of the gut as an immunologic organ, and describes those factors in the gut which impede penetration of potentially harmful macromolecules, particularly the secretory IgA system. Because of the immaturity of this gut function in the young infant, breast feeding should be encouraged for the first six to nine months of life whenever possible.

Inflammatory myopathy, IgA deficiency, and intestinal malabsorption

Two IgA-deficient children with inflammatory myopathy and intestinal malabsorption were evaluated. The myopathy was characterized by weakness of facial and proximal limb muscles, increased serum concentrations of lactic dehydrogenase and creatine phosphokinase, and histologic evidence of inflammation and degeneration of muscle fibers. Features of the intestinal abnormality were blunted villi, interstitial inflammation, and reduction in IgA-containing plasma cells and IgA content of epithelial cells. The myopathy and malabsorption improved with corticosteroid treatment. Circulating antibodies to striated muscle could not be demonstrated in either patient, but one had antibodies to milk and chicken serum proteins. We speculate that IgA deficiency may predispose to the development of inflammatory myopathy.

IgA deficiency, epilepsy, and hydantoin medication

Serum-immunoglobulin concentrations were measured in 364 patients with epilepsy. On dividing the patients into those treated with or without hydantoins, and according to possible aetiological factors, a characteristic pattern emerged. Irrespective of the treatment given, the mean values of IgA were significantly reduced in patients in whom constitutional factors were apparent, including those with familial prevalence of seizures. While IgA was rarely found below 0-6 mg/ml, a limit chosen to define IgA deficiency in patients not treated with hydantoins, the IgA level was subnormal in 20-25% of the patients treated with such drugs. In contrast, the mean concentration of IgA was normal and no individual subnormal values were observed in epileptic patients treated with or without hydantoins whose disease was thought to be secondary to traumatic or infectious events or to metabolic disturbances. The data suggest that epilepsy with constitutional characteristics might predispose to low IgA, but that IgA deficiency only occurs when hydantoins are given. Whether this postulated predisposition is relevant to the aetiology or pathogenesis of epilepsy remained unresolved.

[Angioimmunoblastic adenopathies]

Angio-lymphoblastic lymphadenopathies are a newly described haematological entity, though not rare, characterised by a histological triad (vascular neogenesis, highly polymorphic or predominantly immunoblastic cellular proliferation and the presence of acidophilic protein deposits), a clinical syndrome consisting essentially of voluminous disseminated lymphadenopathy and hepatosplenomegaly and abnormal laboratory findings dominated by a polyclonal dysproteinaemia. This disorder, the first four French cases of which are described here, does not appear to be malignant in its early stages and is sensitive to corticosteroid therapy at that time. Secondary sarcomatous transformation is possible.

IgA deficiency and systemic lupus erythematosus. Occurrence in an oriental woman with idiopathic epilepsy

A 25-year-old Oriental woman developed systemic lupus erythematosus during a course of treatment with carbamazepine for long-standing idiopathic epilepsy. Serum IgA was virtually absent, while secretory IgA was quantitated in a small amount in the saliva and gastric juice. Results of immunofluorescent studies on the rectal mucosa and bone marrow did not show any IgA-producing plasma cells. Antibodies against IgA, IgM, milk protein, and bovine serum were detected in the serum. The ability to develop both circulating antibodies and delayed hypersensitivity against test antigens was suppressed. Enumerations of T lymphocytes and IgG and IgM B lymphocytes were within normal limits, whereas IgA B lymphocytes were decreased in number. Results of chromosomal analyses disclosed various abnormalities.

Kappa-chain deficiency. An immunoglobulin disorder

Since kappa-chain deficiency is an unusual condition, we studied the clinical and laboratory findings in a patient with this deficiency. The patient had cystic fibrosis with concurrent malabsorption, diabetes mellitus and IgA deficiency. The serum levels of IgM and IgG were 0.85 and 7.22 mg per milliliter, respectively. Kappa type IgM and IgG was not present in serum and external secretions; gamma, mu and lambda chains were probably polyclonal in character. Antibodies against kappa chains were not detected in either the patient or the mother. Plasma cells containing kappa-type immunoglobulins were absent in jejunum samples and bone marrow; kappa-chainbearing B lymphocytes could not be detected in blood and bone marrow. The serum of one of the patient's sisters contained trace amounts of kappa-type immunoglobulins. The patient displays a complete absence of kappa-type immunoglobulins, probably owing to a genetic defect.

Selective immunoglobulin M (IgM) deficiency in two immunodeficient adults with recurrent staphylococcal pyoderma

Two adult men with recurrent pyoderma due to Staphylococcus aureus and a selective deficiency of immunoglobulin M (IgM) antibody synthesis are described. An analysis of each patient's polymorphonuclear leukocyte chemotaxis, phagocytosis and killing of Staph. aureus, serum opsonizaiton of Staph. aureus, and serum and lymphocyte-mediated responses to antigenic stimulation was performed. Family studies revealed a possible autosomal dominant inheritance pattern with heterogenetic expression of various dysgammaglobulinemic states in each patient's first degree relatives. In vivo studies of delayed hypersensitivity and in vitro studies of polymorphonuclear leukocyte and lymphocyte function were normal. A defect in IgM, but not in IgG (immunoglobulin G), antibody synthesis to a number of antigens, and a mild decrease in serum opsonic activity to Staph. aureus correctable by heat inactivated normal human serum were found in each patient. In these patients, the recurrent staphulococcal pyoderma prompted an investigation of host defense mechanisms and revealed low to absent IgM levels and a defect in IgM antibody synthesis.

Secretory component deficiency. A disorder of the IgA immune system

We studied a 15-year-old boy with chronic intestinal candidiasis who had normal serum IgA levels without IgA in his secretions. There was an elevated number of peripheral blood lymphocytes bearing surface IgA. In addition, the lymphocytes cultured in vitro with pokeweed mitogen produced IgA as well as other immunoglubulins. Despite this evidence of normal IgA synthetic capacity, the patient had greatly diminished levels of IgA in the saliva and jejunal fluid, and, as estimated by 14C-L-leucine incorporation, could not synthesize IgA locally at intestinal-mucosal sites. Finally, the patient had no detectable free secretory component in saliva or jejunal fluid in contrast to normal persons and to patients with IgA deficiency. The basis of this disorder is probably a defect in the homing of IgA precursor cells to secretory sites or in the selective proliferation/differentiation of IgA cells at such sites.

Fragments of immunoglobulins in human faeces

Fab-fragments of IgG were easily demonstrated in extracts of faeces from healthy infants and children. Employing immunoelectrophoresis with antisera to whole human serum and to Fab-fragments of IgG, a marked precipitation line, likely to represent such fragments, was evident in the cathodal or gamma-region. Usually no precipitate was formed with antisera specific for gamma-heavy chains or Fc-fragments of IgG. Presumably IgG in the gut is partially destroyed before being excreted with faeces. Results of immunoelectrophoresis, gel filtration as well as polyacrylamide gel electrophoresis, using antisera to alpha-heavy chains, indicated the presence of fragments of IgA in some faecal extracts. Fragments of IgA could not be demonstrated in IgA-deficient patients, and no fragments of either class, or only traces of Fab-fragments of IgG, were found in agammaglobulinaemic patients. No antibody activity against rabbit erythrocytes was found in gel filtrations containing such fragments; any reaction was not observed either in the direct agglutination test or in a modified antiglobulin test.

IgA deficiency and severe post-vagotomy diarrhoea

Between January, 1969, and December, 1973, 2058 truncal vagotomies were performed in the Merseyside Regional Health Authority area. 14 of these patients subsequently developed severe post-vagotomy diarrhoea and were extensively investigated. 6 were found to have IgA deficiency. It is suggested that antecedent IgA deficiency may account for the varied reported incidence of severe post-vagotomy diarrhoea and that preoperative screening could reduce the incidence of this complication.

Deficiency of kappa- or lambda-type immunoglobulins

A marked imbalance of the two light chain types of immunoglobulins was observed in two young male adults suffering from primary hypogammaglobulinemia and intrinsic factor-deficient pernicious anemia. In one patient, the kappa/lambda light chain ratio of serum immunoglobulins was 0.01; in the other, it was approximately 6 (normal value, 1.8 +/- 0.3). This light chain imbalance was found within each of the three main immunoglobulin classes. The number of mature immunoglobulin-producing cells in the bone marrow and in the mucosa of the gastrointestinal tract was reduced. The relative frequency of kappa- and lambda-producing cells in these tissues corresponded to the kappa/lambda ratio of serum immunoglobulins. However, the number of peripheral lymphocytes with membrane-associated immunoglobulins as well as the percentage distribution of blood lymphocytes with kappa- or lambda-type immunoglobulins on the membrane were within normal limits in both cases. The results suggested a hitherto unknown defect in the maturation of B-cells leading to an abnormal ratio of kappa- and lambda-type immunoglobulin-secreting cells.

Clinical aspects of protective immunity of the respiratory tract

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Isolation of normal human IgA, IgM and IgG fragments by polyacrylamide beads immunoadsorbents

Polyacrylamide beads antibody immunoabsorbents were used in order to isolate human IgA, IgM and fragments of papain-digested human IgG. The proteins obtained were pure as judged by immunochemical techniques. The antisera raised with these purified proteins were monospecific. The binding capacity and the yield were satisfactory. These antibody immunoadsorbents offer several advantages; a) highly purified antigens can be quickly obtained in a one-step procedure from body fluids; b) their handling is easy especially when using a column; c) they can be used for a long period of time and for many experiments without any noticeable loss in their binding capacity.

A paraprotein in severe combined immunodefeciency disease detected by immunoelectrophoretic analysis of plasma

A qualitative study was made of the plasma immunoglobulins of a child with severe combined immunodeficiency. By immunoelectrophoresis an immunoglobulin with an abnormal electrophoretic mobility was detected. This protein possessed mu heavy chain determinants, gave no detectable reaction with antisera specific for light chains, was of a relatively small molecular size, and was probably not composed of subunits held together by easily reduced disulfide bonds. The light chains that were present in this patient's plasma had a homogeneous electrophoretic mobility. The patient's plasma also contained at least two other immunoglobulins whose antigenic identity could not be established. One of these was abnormal in its electrophoretic mobility. The presence of the abnormal protein with mu determinants in the plasma of the second unrelated child with a similar disease suggests that the detection of this protein may have implications for the diagnosis or classification of immunodeficiency diseases.