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A Saalmüller

Publications and source records attributed to A Saalmüller.

At least 37 records · Page 2Linked to original sources
PubMed1998

Overview of the Second International Workshop to define swine cluster of differentiation (CD) antigens.

The aim of the Second International Swine Cluster of Differentiation (CD) Workshop, supported by the Veterinary Immunology Committee (VIC) of the International Union of Immunological Societies (IUIS), was to standardize the assignment of monoclonal antibodies (mAb) reactive with porcine leukocyte differentiation antigens and to define new antibody clusters. At the summary meeting of the workshop in July, 1995, revisions in the existing nomenclature for Swine CD were approved, so that the rules are now in accord with those for human and ruminant CD. Swine CD numbers will now be given to clusters of mAb to swine orthologues of human CD molecules when homology is proven by (1) suitable tissue distribution and lymphoid cell subset expression, (2) appropriate molecular mass of the antigen recognized by the mAbs, and (3) reactivity of mAbs with the cloned swine gene products, or cross-reactivity of the mAb on the human gene products. In some cases, this reactivity would not be fully proven, mainly due to the lack of cloned gene products; for these CD antigens, the respective clusters will be assigned by the prefix 'w' which will lead to 'wCD' antigens. As a result of the Second International Swine CD Workshop the assignment of 16 mAb to existing CD groups (CD2a, CD4a, CD5a, wCD6, wCD8, CD14, CD18a, wCD21, wCD25) was confirmed, and 2 mAb to existing swine workshop clusters (SWC). More importantly, for the work on the porcine immune system, was the definition of 5 new swine CD antigens, namely CD3 (recognized by 6 new mAb and 3 epitopes), CD16 (1 new mAb), wCD29 (2 mAb), CD45RA (3 mAb) and CD45RC (1 new mAb). Finally, the demarcation of two new SWC molecules in swine, SWC8 (2 mAb) and SWC9 (2 mAb) was confirmed.

Animals↗
PubMed1998

Summary of the first round analyses of the Second International Swine CD Workshop.

The reactivity of 176 monoclonal antibodies (mAb) submitted to the Second International Swine CD Workshop, together with 19 internal standards, was analyzed by flow cytometry on 16 different cell types as a means of establishing the proper cell subset for later detailed clustering analyses. The exact CD subset reactivity of the 19 internal standard mAb had been characterized in the First International Swine CD Workshop. The flow cytometric analyses resulted in 40 data sets which were then subjected to statistical clustering using the Leukocyte Typing Database IV (LTDB4) software. As result of this work, 22 clusters were defined. After review of these results, panels of mAb from the defined first round clusters were assigned to cell subsets. The respective mAb in those first round clusters were then distributed to subset group researchers for further examination during the second round of the workshop.

Animals↗
PubMed1998

Summary of workshop findings for antibodies reacting with porcine T-cells and activation antigens: results from the Second International Swine CD Workshop.

After initial evaluation of the 176 new and 19 control monoclonal antibodies (mAb) submitted to the Second International Swine CD Workshop, 57 were assigned to the T-cell/activation marker subgroup. These 57 mAb were further analyzed using flow cytometry on whole blood lymphocytes, splenocytes, Peyer's patch lymphocytes, in vitro cell lines, broncho-alveolar lavage cells, Con A and PHA blasts, fetal cell populations, and by 2-color flow cytometry against mAb to porcine CD2, CD4, and CD8. Finally, the molecular weights of the target antigens were characterized when possible. As a result of these analyses, 23 mAb were distributed into 7 CD clusters. Newly confirmed mAb assignments included: two CD2; one CD4; two CD5; one wCD6; and one wCD25. Three new mAb were found that reacted with wCD8, one of which defined a new epitope, wCD8c. For the first time, mAb against porcine CD3 were identified, including 6 mAb that reacted with three different epitopes. Several new mAb reacted with antigens whose expression varied depending on the activation state of the test cell. These will require further characterization in order to assign a CD number.

Animals↗
PubMed1998

Analyses of monoclonal antibodies reacting with porcine CD3: results from the Second International Swine CD Workshop.

Among the 57 monoclonal antibodies (mAb) analyzed within the T-cell group from the Second Swine CD Workshop, six mAb fell within clusters T10 and T11 (No. 088, STH164; No. 148, FY1A3; No. 149, FY2C1; No. 150, FY1H2; No. 151, FY2A11; No. 169, BB23-8E6). The mAb within these two groups gave a similar appearance on flow cytometry and stained all peripheral blood T-cells as defined by CD4 and wCD8 staining. All six mAb precipitated a 24 kDa protein. On the basis of inhibition analyses performed as part of the workshop and from published data, the mAb define at least three epitopes. There is only minimal stimulation of resting peripheral lymphocytes, but four of the mAb produce strong stimulation in the presence of PMA. With the exception of STH164, all have been shown to react with CD3 epsilon-transfected COS cells. The new mAb, therefore, react with three epitopes on porcine CD3 epsilon designated CD3a (BB23-8E6, FY2A11), CD3b (FY1A3, FY2C1), and CD3c (FY1H2). mAb STH164 appears to be reactive with another epitope, however, since its reactivity with CD3 has not been confirmed it is designated as wCD3.

Animals↗
PubMed1998

Analyses of monoclonal antibodies reacting with porcine CD5: results from the Second International Swine CD Workshop.

Among the 57 monoclonal antibodies analyzed within the T-cell group, three mAbs fell within cluster T13 including the CD5a standard b53b7 (No. 174). The two new mAbs 1H6/8 (No. 058) and BB6-9G12 (No. 166) both precipitated 55 and 60 kDa proteins that were of similar molecular weights as the standard. Staining patterns on the various cell types were similar. Both new antibodies inhibited the binding of the CD5a reference mAbs b53b7 to peripheral lymphocytes. These mAbs, therefore both react with the CD5a epitope bringing the number of anti-porcine CD5 mAbs to eight, all of which appear to recognize the same epitope.

Animals↗
PubMed1998

Analyses of monoclonal antibodies reacting with porcine wCD6: results from the Second International Swine CD Workshop.

Among the 57 monoclonal antibodies analyzed within the T-cell group of the Second International Swine CD Workshop, one mAb fell within cluster T14a that included the CD6 standard a38b2 (No. 175). The new mAb MIL8 (No. 082) and a38b2 both precipitated from activated T-cells a 150 kDa monomeric protein. Staining patterns on the various cell types were similar. There was no inhibition of binding of either mAb to peripheral blood T-cells with the opposite mAb. The new mAb, MIL8, reacts with a separate epitope on porcine wCD6.

Animals↗
PubMed1998

Report on the analyses of mAb reactive with porcine CD8 for the second international swine CD workshop.

Based on an analysis of their reactivity with porcine peripheral blood lymphocytes (PBL), only three of the 57 mAbs assigned to the T cell/activation marker group were grouped into cluster T9 along with the two wCD8 workshop standard mAbs 76-2-11 (CD8a) and 11/295/33 (CD8b). Their placement was verified through the use of two-color cytofluorometry which established that all three mAbs (STH101, #090; UCP1H12-2, #139; and PG164A, #051) bind exclusively to CD8+ cells. Moreover, like the CD8 standard mAbs, these three mAbs reacted with two proteins with a MW of 33 and 35 kDa from lymphocyte lysates and were, thus, given the wCD8 designation. Because the mAb STH101 inhibited the binding of mAb 76-2-11 but not of 11/295/33, it was given the wCD8a designation. The reactivity of the other two new mAbs in the T9 cluster with the various subsets of CD8+ lymphocytes were distinct from that of the other members in this cluster including the standards. Although the characteristic porcine CD8 staining pattern consisting of CD8low and CD8high cells was obtained with the mAb UCP1H12-2, a wider gap between the fluorescence intensity of the CD8low and CD8high lymphocytes was observed. In contrast, the mAb PG164A, not only exclusively reacted with CD4-/CD8high lymphocytes, but it also failed to recognize CD4/CD8 double positive lymphocytes. It was concluded that this mAb is specific for a previously unrecognized CD8 epitope, and was, thus, given the wCD8c designation. A very similar reactivity pattern to that of PG164A was observed for two other mAbs (STH106, #094; and SwNL554.1, #009). Although these two mAbs were not originally positioned in the T cell subgroup because of their reactivity and their ability to inhibit the binding of PG164A, they were given the wCD8c designation. Overall, five new wCD8 mAbs were identified. Although the molecular basis for the differences in PBL recognition by these mAbs is not yet understood, they will be important in defining the role of CD8+ lymphocyte subsets in health and disease.

Animals↗
PubMed1998

Analysis of monoclonal antibodies that recognize gamma delta T/null cells.

Thirty two monoclonal antibodies (mAbs) from the first round of analysis in the Second International Swine CD Workshop were placed together with additional mAb derived from the first workshop in the null cell panel for further evaluation. Preparations of peripheral blood leukocytes, concanavalin A stimulated peripheral blood mononuclear cells, and spleen cells were used in flow cytometric analyses. Nineteen mAbs identified molecules that were not expressed on null cells, not lineage specific, or recognized activation molecules. Sixteen mAbs including control mAbs were identified that were specific for null cells. One of the latter mAbs, 041 (PGBL22A), that recognizes a determinant on a constant region of porcine gamma delta TcR established the majority of null cells are gamma delta T cells. Use of this mAb in further comparisons demonstrated the gamma delta T cell population is comprised of two major subpopulations, one negative and one positive for CD2. Two color analyses demonstrated that 11 of the mAbs formed a broad cluster that included control mAbs 188 (MAC320) that defined the CD2 negative SWC6 cluster in the first workshop and mAb 122 (CC101) that might recognize an orthologue of bovine WC1 and nine mAbs that recognize determinants on one or more molecules with overlapping patterns of expression on subsets of CD2- gamma delta T cells. Two groups of mAbs formed the previously identified subset clusters SWC4 and SWC5. Two new mAbs formed a third subcluster. Three mAbs did not form clusters. Three mAbs predicted to recognize TcR in the first workshop (020 [PT14A], 021 [PT79A], and 022 [MUC127A]) and mAb PGBL22A were shown to immunoprecipitate a 37, 40 kDa heterodimer.

Animals↗
PubMed1998

Summary of workshop findings for porcine adhesion molecule subgroup.

Fifty-nine monoclonal antibodies (mAb) were assigned to the adhesion section of the Second International Swine CD Workshop. They were analysed for their reactivity to selected lymphoid cell populations, as well as to non-lymphoid cell lines. Cell lysate ELISAS and Western Blot analyses were also carried out. As a result, thirteen separate cluster groups emerged (p > 0.95). Workshop assignments for adhesion molecules were made: wCD29/49 for mAbs UCP1D2 (#133) and FW4-101 (#165), and PNK-I (#194) and MUC76A (#025) could be assigned to wCD18. For one cluster (FQ1D7, #161 and 2F4, #069) the cellular distribution and MW were characteristic for MHC Class II, and another cluster comprising several antibodies which appeared to recognise MHC Class I. Other clusters could not be assigned to cell surface structures known to be linked to cellular adhesion, however, two further antibodies, 335-2 (#112) and FG1F6 (#156), could be added to SWC1, and the new SWC8 was defined by MIL3 (#077) and MUC20A (#029), binding a ligand of 29-32 kDa. Clustering for these two antibodies was confirmed by blocking studies. The cellular distribution is known for MIL3, recognising an epitope present on granulocytes, B cells, and a subset of T cells expressing CD8 at high intensity.

Animals↗
PubMed1998

Definition of the specificity of monoclonal antibodies against porcine CD45 and CD45R: report from the CD45/CD45R and CD44 subgroup of the Second International Swine CD Workshop.

Swine cell binding analyses of a set of 48 monoclonal antibodies (mAbs), including eleven standards, assigned to the CD44 and CD45 subset group of the Second International Swine CD Workshop yielded 13 clusters. Although none of these corresponded to CD44, seven mAbs formed a cluster which was identified as being specific for restricted epitopes of CD45 (CD45R). In addition, a T-cell subset specific cluster comprised of four mAbs was also identified. Two mAbs (STH106 and SwNL 554.1) reacted exclusively with CD8 bright lymphocytes, the other two (2B11 and F01G9) with a subset of CD4 lymphocytes. The other 10 clusters were either specific for MHC-class I like molecules or overlapped with clusters identified by the adhesion molecule subgroup and are therefore just briefly discussed in this report. The specificity of all the mAbs in the CD45R cluster was verified by their ability to immunoprecipitate distinct proteins and to react with CHO cells expressing individual isoforms of CD45. Three CD45R mAbs (3a56, MIL5, -a2) did react with a 210 kDa isoform(s), while another three (STH267, FG2F9, 6E3/7) only recognized a 226 kDa isoform(s). The remaining one (MAC326) precipitated both a 210 and 226 kDa protein. The specificity of all the mAbs in the CD45R cluster, and of the CD45 common mAbs, was confirmed by their reactivity with CHO cells transfected with cDNAs encoding the extracellular and transmembrane portions of distinct CD45R isoforms. Those mAbs recognizing a 210 kDa protein reacted with CHO cells expressing the CD45RC isoform, while those capable of precipitating a 226 kDa, but not the 210 kDa, polypeptide recognized CHO cells expressing either the CD45RAC and the relatively rare CD45RA isoform. MAC326 was unique in its inability to react with CHO cells engineered to produce the CD45RC and CD45RAC isoforms. Thus, three mAbs (6E3/7, STH267, and FG2F9) appear to be specific for an epitope(s) encoded by the A exon, while one (MAC326) recognizes a determinant encoded by the C exon. The remaining three mAbs (3a56, -a2, MIL5) are apparently specific for an epitope(s) which results from the fusion of the C exon to the invariant leader sequence and is destroyed by inclusion of the A exon. All three CD45 common mAbs, K252.1E4, MAC323 and 74.9.3, did react with the CHO cells lines expressing either the CD45RA, CD45RC, CD45RAC or CD45RO isoforms, but not with untransfected CHO cells. When the natural expression of CD45 isoforms was examined by reacting lymphocytes with CD45R mAbs, a high level expression of isoforms containing the A exon-generated domain was detected in all B cells while the majority of CD4+ T cells had undetectable or lower expression density of this protein than B cells. In contrast, the density of expression of the CD45 isoform(s) containing the C exon-generated domain ranged from undetectable to high in CD4+ T cells whereas the amounts were approximately ten-fold lower in B cells. Overall this panel of CD45 mAbs will be very useful in analyzing the maturation and differentiation of swine lymphoid cells subsets.

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PubMed1998

Flow cytometry data included in first round cluster analysis.

Tables 1-16 contain the results of flow cytometry analyses of 18 different cell types labelled with all 176 monoclonal antibodies submitted to the Second International Swine CD workshop. The 19 standards (mAb #171-#189) characterized for their specificity in the first workshop served as controls. Data derived from 40 different analyses are presented as % positive cells.

Animals↗
PubMed1998

Infection with classical swine fever virus: effects on phenotype and immune responsiveness of porcine T lymphocytes.

T lymphocytes obtained from pigs infected with a lethal dose of classical swine fever virus were analysed for phenotypic changes in the composition of T-cell subpopulations and for alterations in their immune responsiveness in vitro during the course of disease. Viral antigen detected in all subpopulations and the selective depletion of CD4- CD8- gamma/delta T cells showed that peripheral blood T lymphocytes were affected in the terminal stage (14-19 days post-infection) of classical swine fever whereas no implications for T lymphocytes were obvious during the first 10 days after infection. Furthermore, a depletion of CD1+ CD4+ CD8+ 'common thymocytes' was characteristic for the infected animals. Studies on immune functions of peripheral T lymphocytes revealed an abrogation of cellular immune responses as early as 3-5 days after infection and thus before detection of viral antigens in these cells. The data suggest that early immunosuppression represents a crucial event for the manifestation of classical swine fever.

Animals↗
PubMed1998

Expression of porcine major histocompatibility antigens in cardiac tissue.

In this study we have used monoclonal antibodies directed against antigens of the major histocompatibility complex (MHC) class I and class II to reveal the detailed cellular distribution of swine lymphocyte alloantigens (SLA) in cardiac tissue. By applying a sensitive immunophosphatase staining reaction we detected the ubiquitous expression of SLA class I and class II on the vascular endothelium. Endothelial cells of capillaries and blood vessels were intensely stained structures in the examined swine hearts. Similar staining patterns were observed in control experiments with anti-von Willebrand factor serum and Dolichus biflorus lectin used as immunohistochemical markers for endothelial cells. The luminal layer of studied pulmonary valves exhibited a strong staining reaction with anti-SLA class I and class II antibodies. In contrast, normal cardiac myocytes failed to express immunodetectable amounts of either of the SLA determinants. Intercalated discs in porcine heart tissue did not react with either anti-SLA class I or class II antibodies. Our data showing the abundant expression of SLA molecules on endothelial cells in normal swine heart may have physiological implications in cell-mediated rejection occurring in xenotransplanted hearts.

Animals↗
PubMed1998

Vaccine-induced, pseudorabies virus-specific, extrathymic CD4+CD8+ memory T-helper cells in swine.

Pseudorabies virus (PRV; suid herpesvirus 1) infection causes heavy economic losses in the pig industry. Therefore, vaccination with live attenuated viruses is practiced in many countries. This vaccination was demonstrated to induce extrathymic virus-specific memory CD4+CD8+ T lymphocytes. Due to their major histocompatibility complex (MHC) class II-restricted proliferation, it is generally believed that these T lymphocytes function as memory T-helper cells. To directly prove this hypothesis, 15-amino-acid, overlapping peptides of the viral glycoprotein gC were used for screening in proliferation assays with peripheral blood mononuclear cells of vaccinated d/d haplotype inbred pigs. In these experiments, two naturally processed T-cell epitopes (T1 and T2) which are MHC class II restricted were identified. It was shown that extrathymic CD4+CD8+ T cells are the T-lymphocyte subpopulation that responds to epitope T2. In addition, we were able to show that cytokine secretion can be induced in these T cells through recall with inactivated PRV and demonstrated that activated PRV-primed CD4+CD8+ T cells are able to induce PRV-specific immunoglobulin synthesis by PRV-primed, resting B cells. Taken together, these results demonstrate that the glycoprotein gC takes part in the priming of humoral anti-PRV memory responses. The experiments identified the first T-cell epitopes so far known to induce the generation of virus-specific CD4+CD8+ memory T lymphocytes and showed that CD4+CD8+ T cells are memory T-helper cells. Therefore, this study describes the generation of virus-specific CD4+CD8+ T cells, which is observed during vaccination, as a part of the potent humoral anti-PRV memory response induced by the vaccine.

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PubMed1998

Antigen-specific immune response of porcine T lymphocytes to various pathogens.

The importance of swine in agriculture has resulted in a substantial increase in research efforts on the swine immune system during the past few years. A better knowledge of the porcine immune system is required before improved vaccination strategies, the design of more efficient vaccines and breeding for disease resistance will be able to contribute to a reduction in the extensive economic losses caused by the disabling effects of viral, bacterial and parasitic infections. T lymphocytes play a central role in the antigen-specific immune response to the various pathogens. To detect and characterise porcine T lymphocytes, monoclonal antibodies (mAbs) were raised against different leucocyte differentiation antigens and classified for specificity in two international workshops. These mAbs have enabled detailed studies to be made on specific cell populations involved in the porcine immune response to pathogens, on T lymphocytes and on the peculiarities of porcine T lymphocyte sub-populations: extra-thymic CD4+CD8+ T lymphocytes and a substantial proportion of CD2-TCR gamma delta+ T cells. Furthermore, these reagents and the increased knowledge of the immune system have allowed studies of the interactions of T lymphocyte sub-populations with regard to different pathogens and the role which these play in infections.

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PubMed1998

[Phenotypic and functional characterization of porcine T-lymphocytes].

Monoclonal antibodies (mAb) against leucocyte differentiation antigens have altered the way in which immunologists examine the immune system. These mAb allow to identify distinct surface molecules on leukocyte populations, by which these cells can be classified, isolated and studied for their functional properties. This review summarises the knowledge about differentiation antigens useful in the characterisation of porcine T-lymphocytes. Furthermore it focuses on several properties of porcine T-lymphocytes and T-lymphocyte subpopulations.

Animals↗
PubMed1997

Early changes in the phenotypic composition of lymphocytes in the bronchoalveolar lavage of pigs after aerogenic immunization with Pasteurella multocida aerosols.

The phenotypic composition of bronchoalveolar lymphocytes (BALL) of healthy untreated pigs and of pigs immunized via aerosol with a live Pasteurella multocida mutant was measured cytofluorometrically in comparison to blood lymphocytes (PBL). Cells were analyzed using monoclonal antibodies against porcine IgM, IgA, IgG and SWC3 in single-colour fluorescence and the following antibody combinations for two-colour fluorescence: CD2/SWC1, SWC1/CD25 and CD4/CD8. In nonimmunized pigs, differences between lymphocyte subsets derived from blood and lung were obvious. The numbers of CD2-SWC1+ T-cells, CD25+ activated lymphocytes and IgG+ cells were significantly higher in the bronchoalveolar compartment. Aerosol immunization with P. multocida caused only insignificant changes in the phenotypic composition of PBL whereas the composition of lung-derived lymphocytes changed markedly. The percentage of CD2-SWC1+ lymphocytes and of CD25+ cells coexpressing the SWC1 antigen in BALL increased up to 10 days after aerosol administration, whereas the percentage of all Ig+ cells decreased. These data reflect an early cellular reaction to an aerogenic immunization with a P. multocida aerosol, characterized by an increase in CD2+ T-cells and a T-cell activation.

Aerosols↗