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M Goodall

Publications and source records attributed to M Goodall.

At least 37 records · Page 2Linked to original sources
PubMed1995

Oligosaccharide-protein interactions in IgG can modulate recognition by Fc gamma receptors.

X-ray crystal structures of IgG-Fc provide evidence of extensive noncovalent interactions between the protein and carbohydrate moieties, and glycosylation, at Asn-297 within the Fc, has been shown to be important for effector functions mediated through Fc gamma receptors expressed on leukocytes. We have applied protein engineering in an attempt to define protein/carbohydrate interactions essential to wild-type biological activity. We demonstrate that replacement of Lys-246, Asp-249, and Glu-258, which make contacts with GlcNac and Gal on the outer alpha[1-->6] arm, do not affect recognition of human chimeric IgG3 by human Fc gamma RI and Fc gamma RII. However, replacement of Asp-265, which make contacts with the primary GlcNac sugar residue and is covalently attached to Asn-297, resulted in loss of recognition of both Fc gamma RI and Fc gamma RII. Similarly, replacement of Asp-265 in mouse IgG2b resulted in loss of recognition by mouse Fc gamma RII. These results suggest that noncovalent contacts of Asp-265 with the primary GlcNac residue are important for maintenance of recognition of IgG by Fc gamma receptors whereas contacts with GlcNac and Gal on the alpha [1-->6] arm do not have a measurable effect. This conclusion was supported by experiments in which galactose-deficient and fully galactosylated forms of a human IgG4-Fc fragment were shown to be equivalent in their ability to inhibit superoxide generation by IgG4 stimulated U937 cells.

Animals↗
PubMed1994

Characterisation of putative monoclonal anti-G3m(u) and anti-G3m(g) reagents and their antigenic determinants.

Monoclonal antibodies (MAbs) against IgG3 allotypic markers were evaluated in haemagglutination inhibition and IgG3 capture ELISA. MAbs PNF69C and 200D1 exhibited G3m(u) and G3m(g) specificity respectively. In HAI target epitopes detected by MAbs were remarkably stable to physiochemical degradation. Western blotting revealed that MAb 200D1, bound to intact IgG3 heavy chain disease protein and not its pFc' fragment; a result consistent with the CH2 domain location of the G3m(g) allotope. The G3m(u) allotope is also located within this domain. Surprisingly anti-G3m(u) MAb PNF69C bound to the pFc' of IgG3-related protein, HW, and to the pFc' of IgG1-related protein, PR, in Western blot.

Antibodies, Monoclonal↗
PubMed1994

Effector mechanisms activated by human IgG subclass antibodies: clinical and molecular aspects. Review article.

Secondary systemic immune responses are predominantly of the IgG class and passive administration of intravenous IgG, from pooled normal serum, is an effective prophylactic and/or therapeutic treatment for patients with defined immunodeficiencies. However, the proportions of each IgG subclass present within a specific antibody response may differ dramatically from that of the total IgG pool. For some antigens the response may be essentially restricted to a single subclass and it may be presumed that the antibody isotype produced has an optimal protective role. The clinical consequences of selective IgG subclass deficiency appears to validate this presumption. In this review we emphasize the differences in effector functions activated by the IgG subclasses and hence the mechanisms responsible for the removal and destruction of antigen/antibody complexes. These studies are relevant to diagnosis and treatment of patients with recurrent infection; the IgG isotype of monoclonal antibodies selected for passive in vivo therapy; the generation of customized antibodies having a pre-determined profile of effector functions and 'immuno-direction' with new vaccines to provoke an antibody response having an isotype profile optimal for the proposed application.

Complement Activation↗
PubMed1993

Control of IgG/Fc glycosylation: a comparison of oligosaccharides from chimeric human/mouse and mouse subclass immunoglobulin Gs.

Oligosaccharide profiles were obtained for chimeric mouse-human antibodies corresponding to each of the human IgG subclasses 1-4, and mouse IgG2b antibodies each expressed in the mouse J558L cell line. These antibodies have specificity for the NIP hapten and form a matched set of IgGs. An IgG4 chimeric antibody (B72.3) produced in the chinese hamster ovary (CHO-K1) cell line was also analysed for carbohydrate. Additionally aglycosylated mutants of this IgG4 (B72.3) and anti-NIP mouse IgG2b were analysed. The total lack of carbohydrate found in the aglycosylated site-directed mutants human chimeric IgG4 B72.3 (Asn 297-->Gln) and mouse IgG2b (Asn 297-->Ala) demonstrates that there are no N-glycosylation sites other than Asn 297. Therefore glycosylation profiles for all the IgGs analysed reflect carbohydrate attached to this site. Factors such as cell type (A), template direction by the IgG heavy chains (B) and culture conditions (C) are shown to influence IgG glycosylation profiles. (A) The anti-NIP IgG antibodies expressed by the J558L cell line may have one or two Gal (alpha 1-->3) Gal residues per oligosaccharide unit, indicative of the presence of (alpha 1-->3) galactosyl transferase in the J558L mouse cell line. (B) The galactosylation profiles obtained for the IgG heavy chains, in particular the preference for galactosylation of the Man (alpha 1-->6) arm rather than the Man (alpha 1-->3) arm, contrary to the beta-galactosyltransferase specificity, suggest that the polypeptide chain may act as a template to influence the extent of galactosylation and hence the proportions of each oligosaccharide incorporated. The IgG2 antibody does not display this galactosylation preference. (C) The extent of galactosylation appears to be influenced by the growth conditions, with the highest levels of galactosylation being found for IgG produced by cells grown in still cultures, rather than cells grown as ascites or in hollow fibre bioreactors. It is concluded that though the profile of glycosylation is controlled predominantly by the glycosylation activity of the cell in which the IgG is expressed, differences between the IgG heavy chain templates of the various subclasses and culture conditions can also influence glycosylation.

Animals↗
PubMed1993

The acquisition of anti-pneumococcal capsular polysaccharide Haemophilus influenzae type b and tetanus toxoid antibodies, with age, in the UK.

Antibody levels specific for capsular polysaccharides of Streptococcus pneumoniae and Haemophilus influenzae type b (Hib) and to tetanus toxoid (TT), were measured in serum samples of 750 age-stratified subjects from the UK. The study subjects comprised healthy adult volunteers and hospitalized children undergoing elective surgery, excluding those with a history of infection or under investigation for immunological or haematological disorders. These antibody levels were calibrated by comparison with serum pool obtained from healthy adult volunteers, who were immunized with Hib polyribose-phosphate vaccine (Merieux). The data are intended to provide reference ranges to assist in the interpretation of specific antibody measurements in the clinical setting. Maternal IgG pneumococcal capsular polysaccharide (PCP) specific antibody levels, geometric-mean titre (GMT) 1/22, were lost by 6 months of age (GMT of 1/9). They remained low until 3-5 years (GMT of 1/20), and consisted principally of IgG1. Thereafter, IgG anti-PCP antibody titres increased steadily to adult levels (GMT of 1/275), of which 80% was IgG2. Anti-PCP antibody titres of the IgM isotype rose steadily from a GMT 1/21 (0-6 months) to 1/420 (3-5 years), a level which was maintained until adulthood. Anti-Hib antibody concentrations, determined by RABA, again demonstrated the decline in maternal antibody, from 0.18 micrograms/ml in the 0-6 month age cohort, to 0.09 microgram/ml between 6 and 12 months. Geometric-mean antibody concentrations remained below 0.2 micrograms/ml until 3-5 years, then increased with age, attaining the mean adult level of 1.02 micrograms/ml. Anti-TT antibody concentrations were measured in the same sera, by ELISA. Two peaks in anti-TT antibody levels were seen in children of 0.059 IU/ml and 0.166 IU/ml corresponding to the schedule of routine childhood immunization in the first year and at 5 years of age.

Adolescent↗
PubMed1993

Glycosylation of human IgG subclass and mouse IgG2b heavy chains secreted by mouse J558L transfectoma cell lines as chimeric antibodies.

Oligosaccharide profiles for monoclonal chimeric mouse-human and mouse IgG2b antibodies produced in the mouse J558L cell line have been determined. These chimeric antibodies share the same mouse light chain and VH region and have a single, complex, oligosaccharide moiety attached to residue 297 of the heavy chain. Since the panel of chimeric antibodies included each of the human IgG subclasses and a set of IgG3 proteins having single residue differences, it was possible to evaluate the contributions of the protein template, the cell line, and the culture conditions to glycosylation. The study shows that the J558L cell line glycosylates human heavy chains with oligosaccharides characteristic of mouse immunoglobulins. This includes a galactose alpha 1-->3 galactose structure not found in human IgG and for which most humans have naturally occurring "anti-Gal" antibodies. The extent of galactosylation was very dependent on the culture conditions and was maximal for still culture. The findings have significance for the production of antibodies for in vivo administration.

Animals↗
PubMed1992

Multiple binding sites on the CH2 domain of IgG for mouse Fc gamma R11.

Important mammalian defensive functions such as phagocytosis are triggered in leukocytes by the interaction of the Fc region of IgG with cell surface receptors (Fc gamma R). The CH2 domain of IgG has been implicated previously as the site of interaction with human and mouse Fc gamma R. This domain was mapped for interaction with mouse Fc gamma R11 expressed by the macrophage-like cell line P388D1, using two panels of a total of 32 site-directed mutants of mouse IgG2b and chimeric human IgG3 monoclonal antibodies. Two potential binding sites have been identified: one in or within the vicinity of the lower hinge site on IgG for human Fc gamma R1, and one within the binding site on IgG for Clq. The three mutant IgGs (Gly 237----Ala, Asn 297----Ala, and Glu 318----Ala) which do not interact in complexed form also fail to bind as monomers. A 1H NMR study of the three non-binding monomeric mutants suggests that the mutations are largely site-specific, indicating that IgG interacts with mouse Fc gamma R11 at two regions within the CH2 domain. This interaction dictates phagocytosis mediated by Fc gamma R11 of the P388D1 cell line.

Animals↗
PubMed1992

An association between homozygous C3 deficiency and low levels of anti-pneumococcal capsular polysaccharide antibodies.

Inherited deficiencies of complement components are associated with an increased risk of infection by encapsulated, high grade bacterial pathogens such as Streptococcus pneumoniae, Haemophilus influenzae type b and Neisseria meningitidis. Hence, the levels of antibodies to bacterial capsular polysaccharide antigens were measured using ELISA in 65 patients with inherited deficiencies covering the classical, alternative and terminal components of the complement cascade. Three of the four C3-deficient individuals studied were found to be almost totally deficient in specific anti-pneumococcal capsular polysaccharide (PCP) antibodies. These individuals had a history of recurrent pneumococcal sepsis. While single individuals with C1r, C2 and C1Inh deficiency were found to have low anti-PCP antibody levels, no other group of complement deficiency had significantly reduced anti-PCP antibody levels compared with 100 controls. Antibody levels to the other two polysaccharides were not significantly lower in the patient groups. These findings suggest that C3 may be able to provide a stimulatory signal to promote the production of anti-PCP antibodies.

Adolescent↗
PubMed1990

Evaluation of monoclonal antibodies with putative specificity for human IgG allotypes.

Fourteen monoclonal antibodies (MAbs) of putative specificity for human IgG allotypes and isoallotypes were evaluated for reactivity and specificity in 8 different assay systems. The study showed that the MAbs tested could be classified into 1 of 4 groups: those exhibiting allotypic specificity regardless of the assay system, allotypic specificity dependent on the assay system, isoallotypic specificity, and those showing neither allotypic nor isoallotypic specificity. These observations were presumably dependent on antigen presentation, epitope integrity and/or antibody multispecificity. For the G1m(a), G1m(f), G1m(z), G3m(g) and G3m(u) specificities, MAbs have been produced which can be used for routine typing purposes in defined haemagglutination and enzyme-linked immunosorbent assay systems. MAbs are also available that show 'non-g' isoallotypic specificity.

Animals↗
PubMed1988

Kappa/lambda immunoglobulin distribution in Graves' thyroid-stimulating antibodies. Simultaneous analysis of C lambda gene polymorphisms.

From patients with untreated Graves' disease 11 sera showing high cAMP release in the FRTL-5 cell assay were studied for relative proportions of kappa or lambda Ig molecules showing cAMP releasing activity. Immunoabsorption of gamma-globulins was performed using monoclonal murine anti-kappa or anti-lambda antibodies linked to cyanogen bromide-activated sepharose. Specific kappa- or lambda-adsorbed fractions were also eluted from immunoabsorbents using chaotrophic thiocyanate buffers and equilibrated with pH 7.4 low salt buffer by dialysis. Immunoabsorption and elution experiments showed that five Graves' sera contained predominant cAMP-releasing activity within lambda Ig fractions, whereas two Graves' sera showed predominant cAMP-releasing activity in kappa Ig fractions. Four sera showed cAMP release approximately equally divided between kappa and lambda Ig both after immunoabsorption and specific anti-kappa or anti-lambda eluates were studied. C lambda genotypes were examined by Southern blotting and restriction fragment length polymorphism analysis of Eco RI-digested genomic DNA from 158 patients with Graves' disease in parallel with 112 normal controls and 29 patients with autoimmune hypothyroidism. Notable shifts in proportions of 8/8 and 18/18 genotypes were present when Graves' patients were compared with normal controls. Allelic frequencies and ratios of genotype 8 to 18 were significantly different (P less than 0.05) when Graves' patients were compared either to normal controls or to patients with autoimmune hypothyroidism.

Absorption↗
PubMed1988

Individual variation in the isotype profile of anti-histone autoantibodies in systemic lupus erythematosus.

Using a solid-phase radioimmunoassay we have measured levels of anti-histone autoantibodies of the IgG, IgA and IgM heavy chain classes in 40 patients with systemic lupus erythematosus. Twenty-two patients (55%) had significantly elevated levels of at least one anti-histone isotype. Our results reveal four characteristics of the anti-histone response. (1) There is wide variation between patients in the isotype profile of anti-histone antibodies and these isotype profiles are a consistent individual characteristic. (2) There is no significant correlation between the level of IgG, IgA and IgM anti-histone in individual patients and a marked tendency for a single isotype (either IgG, IgA or IgM) to predominate in any one patient. (3) IgG anti-histone antibodies are predominantly of the IgG1 subclass. (4) Among 12 patients tested, IgG and IgA antibodies showed a preference for histones 1 and 2B whereas IgM antibodies showed no consistent preference for individual histones.

Adult↗
PubMed1987

Use of monoclonal antibodies in an ELISA to detect IgM class antibodies specific for Toxoplasma gondii.

Two monoclonal antibodies CH6 and C1E3 were used in an antibody class capture assay for the detection of IgM antibodies specific for Toxoplasma gondii. CH6 was used on the solid phase to capture human IgM. After a Toxoplasma gondii antigen had been added, specifically bound material was detected using C1E3 coupled to horseradish peroxidase. The assay was compared with an established system using polyclonal antisera at both the capture and antigen detection stages. A good correlation was found, with 97.3% (125 of 128) of sera giving the same classification in both assays. Three sera were positive only in the polyclonal system. No false positive results were found when 118 negative sera were examined. The two monoclonal antibodies provide a viable alternative to the use of polyclonal sera at the capture and antigen detection stages in the antibody class capture assay for the measurement of specific IgM against T gondii.

Animals↗
PubMed1985

Hypomagnesaemia: an underdiagnosed interaction between gentamicin and cytotoxic chemotherapy for acute non-lymphoblastic leukaemia.

Hypomagnesaemia occurred in 6 of 11 leukaemic patients who received gentamicin. This problem has been reported relatively infrequently when gentamicin is used alone. Our hypomagnesaemic patients received concurrent courses of gentamicin with cytotoxic therapy significantly more often but it is not clear whether this represents a true drug interaction or an interaction between gentamicin and the products of cell lysis produced by cytotoxic treatment. The incidence of this problem has been underestimated previously because hypocalcaemia was used as an indicator. Renal wasting of magnesium is well documented as the mechanism by which the hypomagnesaemia is sustained but further investigation is required to see whether other factors are involved in its initiation.

Adolescent↗
PubMed1975

Urinary 5-hydroxyindoleacetic acid in 8-hour collections as an aid in diagnosis of coeliac disease.

8-hour urine excretions of 5-hydroxyindoleacetic acid (5-HIAA) were measured in 18 children with coeliac disease before treatment and the results expressed as microgram 5-HIAA/mg creatinine. Similar measurements were made on urine collections from an age-matched control group of 24 children. Significantly higher values of 5-HIAA excretion were found in children with untreated coeliac disease. Measurement of the 5-HIAA: creatinine ratio in 8-hour urine collections is therefore proposed as an aid in the diagnosis of coeliac disease.

Celiac Disease↗