Biomedical subjects

D W Dresser

Publications and source records attributed to D W Dresser.

At least 37 records · Page 2Linked to original sources

PubMed1985

Fetal stimulation of maternal immunoglobulin production in mice.

Within 12-24 h of parturition in mice, there was a dramatic increase in the number of immunoglobulin secreting cells in the paraaortic lymph nodes (PALN) draining the pregnant uterus. Compared with stimulation with lipopolysaccharide the ratio of IgG:IgM forming cells was very high in PALN draining a pregnant uterus. The response was eliminated when fetectomy (ablating the embryo but leaving the placenta intact) was carried out on the 12th day of pregnancy. With unilateral fetectomy the uterine horn with intact fetal/placental units can be used as a positive control since lymphoid drainage is laterally confined. Neither healthy (gross and histological criteria) nor partly necrotic placentae stimulated Ig secreting cells in the PALN. The placentae of bilaterally fetectomized females were delivered apparently normally and at about the same time as normal (control) fetuses. Injection of prostaglandin E-2 or F-2 alpha into the tail base led to the appearance of Ig-forming cells in the PALN of normal (virgin) female mice. Indomethacin fed to the pregnant female greatly reduced the numbers of these cells in the PALN. We conclude that the observed local stimulation of maternal Ig production by the fetus may be involved in the transplacental transfer of Ig from mother to fetus.

Animals↗

PubMed1985

Increases in the numbers of immunoglobulin-secreting cells in lymph nodes responding to sperm and other stimuli: possible relationship to immunosuppression.

It has been reported that, in early pregnancy in mice, there is an increase in the number of immunoglobulin-secreting cells in the lymph nodes which drain the uterus. This paper describes the results of further investigations provoked by interest in these early changes. Increases in the numbers of immunoglobulin-secreting cells were observed in syngeneically, but scarcely or not at all in allogeneically, mated mice. Increases were not observed in surgically sterilized female mice inseminated by normal males. However, subcutaneous injection of sperm provoked massive increases in the numbers of immunoglobulin-secreting cells in the lymph nodes draining the injection site. The changes were compared with those provoked by the injection of spleen cells and LPS. The results are discussed in relation to the nature of the interactions provoking the increases in the number of immunoglobulin-secreting cells and their possible relationship to immunosuppression, and the relative immunological unresponsiveness which the female shows to the challenge of inseminated sperm.

Animals↗

PubMed1984

Antibody-mediated allotype suppression in adult mice: the role of antigen, effector isotype and regulatory T cells.

It has been reported (Contemp. Top. Immunobiol. 1974. 3:41) that allotype-specific T suppressor cells can be induced after monoclonal anti-allotype treatment of neonatal (BALB/c X SJL)F1 (Igha/b) mice. Here we show that (BALB/c X CB20)F1 adult-derived spleen cells (SC) are, by contrast, potently suppressed by monoclonal allotype-specific reagents, (when transferred into irradiated BALB/c recipients) in the absence of primary T suppressor cell induction. Such suppression is only induced in activated B cells [exposed to lipopolysaccharide or sheep red blood cells (SRBC)], and is probably dependent on the isotype of the anti-allotype sera administered. For example, two independently produced IgG1 monoclonal reagents raised against the Igh-1b allotype were poorly suppressive or nonsuppressive, whereas an IgG3 and an IgG2a monoclonal antibody induced a 90% suppression of the target allotype in transferred adult SC. It was found that suppression was not due to a depletion of antigen-specific T cell help since: (a) the addition of SRBC-educated T cells did not break suppression and (b) suppressed SC were as good a source of T cell help as normal SC, in the response of virgin or memory B cell (Thy-1-depleted) responses to SRBC in vivo. Suppression was maintained in suppressed cells which had been rechallenged with SRBC after transfer into a second irradiated recipient, but was not induced in normal SC when these were admixed with an equal number from this suppressed SC population. These findings point to a possible mechanism for the regulation of B cell expression, through the formation of an antibody-Ig receptor complex at the surface of the B lymphocyte. After complexing the target cell is either deleted or inactivated. The response to SRBC was reduced or ablated for at least 70 days after treatment with a single dose of anti-allotype serum.

Animals↗

PubMed1984

Allotype suppression in an adoptive transfer system in adult mice: the specificity and feedback effects of a monoclonal IgG3 anti-(Igh-1b) allotype antibody.

Using an adoptive transfer system in mice, an allotype-specific suppression has been induced by a monoclonal IgG3 anti-Igh-1b (Hyb 5.7) reagent. Suppression was specific for IgG2a (Igh-1b) and led to a compensatory increase of the Igh-1a response in irradiated mice reconstituted with allotype heterozygous (Igha/b) spleen cells. Suppression, which was not antigen-specific, lasted for at least 1 month after anti-allotype treatment.

Animals↗

PubMed1983

Flow microfluorometric analysis of living spermatozoa stained with Hoechst 33342.

Bovine spermatozoa were stained with Hoechst 33342. The fluorescence distribution of stained spermatozoa was complex. Non-motile spermatozoa displayed a higher fluorescence than did motile spermatozoa. The fluorescence profile of the motile spermatozoa was bimodal. Sort and reanalysis, and orientation experiments suggested that there are two distinct populations of motile spermatozoa.

Animals↗

PubMed1983

Anti-idiotype regulation of the formation of IgE antibody to timothy grass pollen. II. In vitro induction of suppressor T cells in mini-Marbrook cultures.

A method is described for using mini-Marbrook chambers for culturing spleen cells together with anti-idiotype antibody (anti-Id) to induce the appearance of suppressor T cells (Ts). Spleen cells that have been cultured with affinity prepared anti-Id (IgG) but not those cultured with normal IgG, suppress a secondary IgE response to timothy grass pollen antigen B (AgB) when injected intravenously into AGB-primed and boosted syngeneic recipient mice. Suppressor T cells are not induced if the spleen cells cultured with anti-Id are depleted of B cells of if the cells are cultured with the F(ab)2 fragment of anti-Id: both of these results are compatible with Fc+ cells playing a role in the induction of Ts cells by anti-Id. Analysis of soluble suppressor factors in an ELISA test suggests that both TS1 and TS2 cells may be induced by anti-Id.

Animals↗

PubMed1983

Regulation of timothy grass pollen IgE antibody formation. I. In-vitro induction of suppressor T cells by soluble T suppressor factors.

A method using mini-Marbrook chambers in culturing normal spleen cells with timothy-specific T suppressor factor TSF and second order T suppressor factor TSF2 to induce suppressor T (TS) cells is described. Spleen cells cultured with T suppressor factors injected intravenously into recipients primed 20 days earlier with antigen and boosted with antigen within 24 hr of cell transfer, significantly suppress a secondary anti-antigen-B (AgB)-IgE response. On the other hand, spleen cells cultured with normal rabbit IgG failed to suppress the secondary anti-AgB-IgE response in recipient mice. The failure of enriched T cells cultured with either TSF or TSF2 to produce TS cells suggest that an accessory cell may be important in 'presentation' of these soluble factors during the induction of TS cells.

Animals↗

PubMed1983

Pretreatment of mice with anti-IgD serum does not result in suppression of immune responsiveness induced by TNP-AECM-Ficoll or lipopolysaccharide.

Unlike the suppression of a primary response to a thymus-dependent antigen, pretreatment of mice with anti-IgD serum has no effect on the response to a thymus-independent (TI) antigen. It has also been shown that anti-IgD serum injected parenterally into mice 2 days previously, has no suppressive effect on non-specific responsiveness to an intraperitoneal injection of LPS. There is a similar lack of effect on the non-specific element of responsiveness to a TI antigen. These results provide in vivo confirmation of the results of previous in vitro experimentation.

Animals↗

PubMed1983

FACS analysis of changes in T and B lymphocyte populations in the blood, spleen and lymph nodes of pregnant mice.

Using the fluorescence-activated cell sorter (FACS), the percentages of T and B lymphocytes in the peripheral blood, spleen and lymph nodes of CBA syngeneic and allogeneic pregnancies were determined. At 19 days of syngeneic pregnancy, the level of T cells in the blood had decreased and that of B cells had increased. In the spleen, a decrease in both T and B cells occurred earlier in pregnancy and had returned to control levels by 19 days. During the last few days of pregnancy, the para-aortic lymph nodes (PALN) draining the pregnant uterus of syngeneically mated mice showed a 1 . 7-fold increase in the level of B cells over that in virgin controls. The T-cell level dropped at the end of pregnancy by approximately 10%. There was no change in T- or B-cell status in the brachial (underarm) nodes taken from the same animals.

Animals↗

PubMed1983

Pregnancy induces an increase in the number of immunoglobulin-secreting cells.

The effect of pregnancy on the immune status of CBA mice has been measured in terms of Ig-secreting cells. Reversed plaque assays show that there is a considerable increase in numbers of IgG- and, to a lesser extent, IgM-secreting cells in the para-aortic lymph nodes. Similar but muted responses were observed in the spleen and among the lymphocytes of the peripheral blood. Analysis of cells sorted for intensity of staining for surface Ig in a fluorescence-activated cell sorter (FACS), shows that Ig-secreting cells are confined to a population of very weakly staining cells. The 'response' in syngeneic pregnancies (CBA x CBA) is at least as great as that seen in allogeneic pregnancies (CBA x C57). Active immunity to a xenogeneic erythrocyte antigen is potentiated by pregnancy.

Animals↗

PubMed1982

Quantitative inheritance of heterophile rheumatoid factor responsiveness in mice.

A heterophile rheumatoid factor (RF) response to LPS was measured in mice by means of a plaque assay using target cells coated with bovine IgG. CBA mice were high responders and A, and DBA/2 were low responders, while strains C57Bl, and LP/J showed low to intermediate responsiveness. Use of appropriate congenic strains confirmed that responsiveness is not closely associated with either H-2 or Igh. Failure to respond is not likely to be due to a V-region deficiency, nor can it be readily circumvented, by heterosis (complementation) or the use of high doses of LPS or an extra virulent form of LPS. Breeding experiments show a quantitative trait with maternal responder status having a measurably positive effect.

Animals↗

PubMed1982

Anti-idiotype regulation of timothy grass pollen IgE antibody formation. I. In vivo induction of suppressor T cells.

Antibodies prepared against antigen B-specific T-helper factor (anti-THF) and antigen B-specific IgE (anti-IgEid) have been isolated and the anti-idiotypic properties of both antibodies were described previously. Both anti-idiotypic antibodies (anti-Id) were used to determine their influence in primary and secondary IgE responses. These studies demonstrated that both anti-Id specifically suppress timothy IgE responses, that the suppression lasts for at least 35 days, and that it is mediated by a Thy 1+ Lyt 1- 23+ T cell. Attempts to induce suppressor T cells with the F(ab)2 fragment of anti-THF at several concentrations (10-80 micrograms per day for 3 successive days) were unsuccessful. This suggests that the Fc portion may be important in presentation of anti-Id during the induction of suppressor T cells.

Animals↗

PubMed1982

Differences in putative minor histocompatibility but not IgH genes can prevent T-cell priming and T--B co-operation in the response of mice to sheep erythrocytes.

A positive association has been observed in Igh allotype "congenic' mice between skin graft rejection and a block to effective T--B co-operation in the development of both IgM and IgG responses to sheep erythrocytes. Mismatch of Igh alone is insufficient for such a block to become apparent since pairs of Igh-allotype congenic strains of mice which reciprocally accept skin grafts for at least 5 weeks, show successful positive co-operation (help) between T and B cells. The observed block is manifest both during the education (priming) of T cells in irradiated (first stage) recipients and during co-operation between primed T cells and unprimed B cells in second stage irradiated "syngeneic' recipients.

Animals↗

PubMed1981

Allotype suppression induced in the adoptive transfer system: the variables of the system and an apparent absence of a role for T cells.

A study has been made of the variables concerned in allotype suppression of adult spleen cells in the adoptive transfer system. These are; SRBC (antigen) dose; the dose and timing of injection of anti-allotype serum IgG; the number of spleen cells transferred and whether these cells were taken from primed or unprimed donors. Adoptively transferred primed cells are considerably less susceptible to suppression by concomitantly injected anti-allotype serum IgG than are unprimed spleen cells. Injection of anti-allotype serum during the period after adoptive transfer, has shown that primed cells loose their susceptibility sooner (2 days) than the unprimed cells (4 days). Allotype heterozygous CBA spleen cells are less susceptible heterozygous CBA spleen cells are less susceptible to allotype suppression than either allotypically homozygous or heterozygous non-H-2k cells (H-2b,d, or s). Allotype suppression of the TI IgG response to DNP-Ficoll was measured 7 days after adoptive transfer of allotype-homozygous cells from both normal and nude CBA mice (unprimed). The results indicate that T cells do not play a role in the initiation of short-term allotype suppression in the adoptive transfer system.

Animals↗

PubMed1981

Allotype suppression of the responsiveness of adoptively transferred adult spleen cells induced by affinity prepared anti-allotype antibody.

In an adoptive transfer assay it has been shown that a form of allotype suppression can be induced in adult spleen cells. Use of SPF congenic mice, and either anti-allotype serum freed of IgM rheumatoid factor or affinity prepared antibody, has helped to eliminate the possibility of a role for non-specific factors in allotype suppression. Both memory-cell development and a conventional primary response are more susceptible to suppression than memory expression in a secondary response. Non-specific suppressive effects on isotypes other than that of the target allotype (CH) are present but are much smaller than for specific suppression.

Animals↗

PubMed1980

Rheumatoid factors in mice: non-specific activators of heterophile rheumatoid factor production.

Although possibly the best, LPS is by no means the only non-specific activator of immune responsiveness (AIr). Plant lectins such as PHA and PWM have some ability to stimulate both total IgM production (reverse IgM PFC) and more particularly heterophile and homophile IgM rheumatoid factor (RF) responses, together with IgM 'antibody' responses to target antigens such as xenogeneic red blood cells or haptens such as TNP. Some parasitic infections and/or parasite antigens were shown to be powerful non-specific AIr, while the injection of dextran sulphate was shown to lead to a great increase in spleen cellularity and total IgM (reverse) PFC but failed to stimulate a heterophile (BIG) RF PFC response.

Acetylmuramyl-Alanyl-Isoglutamine↗

PubMed1980

Rheumatoid factors in mice: plaque assay for homophile and heterophile rheumatoid factors.

It was found that a high proportion of IgM-producing cells secrete homophile or heterophile rheumatoid factors (RF). Injection of lipopolysaccharide (LPS) into CBA mice resulted in a sharp increase in total IgM and in RF-producing cells and in some cases resulted in an increase in RF-producing cells as a proportion of total IgM. RF plaques are indirect IgM in the sense that they require development by IgG2 (anti-IgM) antibody for visualization in a standard haemolytic plaque assay. The RF response to LPS is both dose- and time-dependent.

Animals↗

PubMed1979

Restricted heterogeneity of antibody synthesized by T-cell deprived mice.

Mice which had been thymectomized and injected with anti-thymocyte serum to remove long-lived recirculating T cells, initially failed to produce haemagglutinating and haemolysing antibody after injection of sheep erythrocytes. After six fortnightly injections of heterologous erythrocytes, however, haemolysin titres in the T-cell deprived mice were comparable to those in similarly challenged but immunologically intact animals. Isoelectric focusing of these sera indicated that the anti-sheep erythrocyte antibody eventually synthesized by the T-cell deprived mice was less heterogeneous than antibodies found in the sera of control mice.

Animals↗