Intestinal goblet cell differentiation in Nippostrongylus-infected rats after transfer of fractionated thoracic duct lymphocytes

Adoptive immunization of Nippostrongylus-infected rats augmented goblet cell differentiation in the intestinal epithelium. After fractionation of immune thoracic duct lymphocytes (TDL), cells lacking surface immunoglobulin (sIg-) were the most potent stimulators of goblet cell differentiation. Moreover, TDL drained from rats harbouring a primary infection were more effective than TDL from hyperimmune rats.

Reassortment of lymphocytes in lymph from normal and allografted sheep

The distribution and nature of surface immunoglobulin-bearing (SIg) cells were studied in various sources of lymph from normal sheep and from sheep bearing renal autografts and renal allografts. In normal sheep, 12.2% +/- 1.5 of all mononuclear cells in peripheral lymph SIg and, of these, more than 50% were monocytes and macrophages. Less than 6% of the lymphocytes in peripheral lymph carried SIg. In contrast, 24.7% +/- 1.3 of the mononuclear cells in central lymph had SIg, and all of the labeled cells were lymphocytes. The frequencies of SIg cells in peripheral lymph issuing from renal autografts and from renal allografts were 6.7% +/- 1.3 and 6.9% +/- 0.8, respectively, and the labeled cells were predominantly lymphocytes. The proportion of SIg cells in central lymph from graft-bearing sheep was similar to that from normal sheep. The differences between central lymph and peripheral lymph from both normal and graft-bearing sheep are thought to reflect a restriction on the passage of SIg cells through capillary endothelium in nonlymphoid tissues.

Cytotoxic mechanisms detected in vitro following sheep renal allografts

Cytotoxic effects of lymph and blood components, removed from sheep following renal allografting were determined by in vitro assay using 51Cr labelled donor sheep lymphocytes as target cells. Lytic antibodies were detected in lymph efferent from the node draining the graft site and at lower concentrations in blood serum and in lymph leaving the graft. The cytotoxic antibodies had both complement-dependent and leucocyte-dependent functions; the complement-dependent antibodies were fractionated and shown to be of IgM and IgG1 subclasses. Cytotoxic cells were found in lymph leaving the graft but not in blood or in lymph efferent from the draining node; those detected in the renal lymph were non-specific in action and their appearance correlated with increased numbers of macrophages.

Leukocyte-dependent antibody in sheep immunized with murine mastocytoma cells

Sheep serum removed after hyperimmunization with murine P-815 mastocytoma cells was fractionated and two types of cytotoxic antibody were isolated. Complement-dependent antibody (CDA) was detected in the IgM and IgG1 fractions whereas "leukocyte" -dependent antibody (LDA) was found in the IgG1 and IgG2 fractions. Effector cells that mediated LDA cytotoxicity were isolated from sheep blood but not from sheep lymph, showing that recirculating lymphocytes do not have LDA effector function. Removal of adherent cells from blood leukocyte suspensions reduced antibody-mediated cytotoxicity, suggesting that LDA effector leukocytes may be a heterogenous population containing both adherent and nonadherent cells.

Synthesis of antibody and immunoglobulins without detectable antibody function in cells responding to horseradish peroxidase

The kinetics of immunoglobulin-synthesizing cells (IFC) and antibody-forming cells (AFC) are compared in the popliteal nodes of mice challenged, in the hind footpads, with horseradish peroxidase (PO) in Freund's complete adjuvant. A rise in the number of IFC without antibody function precedes the appearance of AFC. IFC reach peak numbers 7 days before AFC. Control experiments show that the majority of IFC without antibody function are responding to PO and not to adjuvant. Kinetic and radioautographic data suggest that IFC arise by division and differentiation; however, the doubling time of AFC is too rapid to be accounted for by cell division alone. Double staining techniques revealed the presence of immunoglobulin and antibody in different compartments of the same cell in 5 to 15% of the AFC. It is postulated that some AFC are recruited, possibly from cells already synthesizing immunoglobulin determinants.

Intracellular distribution of antibody in immunocytes responding to primary challenge with horseradish peroxidase

A new improved technic was used to follow the development of, and the intracellular antibody distribution in antiperoxidase antibody-forming cells (AFC) of the mouse popliteal lymph nodes responding to primary stimulation with horse-radish peroxidase (HRP). The first AFC were found 6 to 8 days after immunization and were all plasma cells. Antibody was concentrated in the Golgi complexes and in a few cisternae of rough endoplasmic reticulum. Subsequently, an increasing proportion of the AFC were filled with antibody, and with time the numbers of full cells and the intensity with which they stained increased. Kinetic studies of the cell changes in the lymph node medulla suggest that lymphoid cells proliferate, differentiate into plasma cells, and are then recruited as AFC. Furthermore, it was concluded that the changing intracellular distribution of antibody represents the gradual filling of the AFC with specific antibody.

Intracellular distribution of antibody in immunocytes responding to secondary challenge with horseradish peroxidase

A new improved immunoperoxidase method was used to study the antiperoxidase antibody-forming cells (AFC) in the medullae of mouse popliteal nodes after a second challenge with horseradish peroxidase (HRP). Two populations of AFC were found: a) A stable nondividing background population of mature plasma cells whose content of antibody increased 3 days after challenge and b) A new population of cells which increased in number exponentially between 18 hours and 5 days after challenge. In contrast with the first response, the new AFC included many stimulated lymphoid cells, significant numbers of small lymphocytes, and plasma cells. The results suggest that the morphology of the AFC found in the first and second responses reflects the stage in their developmental cycle at which the precursor cells are recruited into the AFC population. More than 90% of the AFC arising between 18 hours and 3 days after challenge had antibody in their perinuclear cisternae, and their cisternae of rough endoplasmic reticulum were rapidly filled with antibody. The striking differences between the intracellular localisation of antibody during the first and second responses are discussed.

Immune reactions in mucous membranes. IV. Histochemistry of intestinal mast cells during helminth expulsion in the rat

The histochemistry of intestinal (IMC) and connective tissue mast cells (CTMC) in the normal rat is compared. Acid mucopolysaccharide appears to be less strongly sulfated and the granule content of monoamines is lower in IMC. After infection with the intestinal helminth, Nippostrongylus brasiliensis, the mucosal content of IMC is altered. During the early phase of immunologic expulsion of this parasite (self-cure) the IMC proliferate and differentiate; the histochemical properties of the granules appear to reflect this process. Very large numbers of mature IMC are found in the mucosa during the later, rapid phase of worm expulsion. Both acid mucopolysaccharide and monoamines are depleted from the granules of these cells; this is consistent with previous studies suggesting that IMC discharge occurs at this stage. These findings lend further support to the hypothesis that the biogenic products of IMC discharge are responsible for the increase in mucosal permeability which occurs during self-cure and which may facilitate the rapid translocation of antiworm antibody into the intestinal lumen.

Ultrastructural localisation of antigen in plasma cells

Following a second injection of horse-radish peroxidase (HPO) or <i>E. coli</i> alkaline phosphatase into the hind foot pads of immune mice, the medullae of the popliteal lymph nodes were examined for plasma cells containing antigen. Small numbers of plasma cells containing HPO were observed 8, 18 and 42 h after injection, but not at 3 and 5 days. The antigen was located in the cisternae of the rough endoplasmic reticulum of large mature-looking plasma cells. It is suggested that HPO antigen is taken up by plasma cells which are already producing specific antibodies. No alkaline phosphatase antigen was detected in plasma cells, the possible reasons for this are discussed.

Immune reactions in mucous membranes. I. Intestinal mast cell response during helminth expulsion in the rat

Measurement of the mast cell response in the jejunal mucosae of rats infected with Nippostrongylus brasiliensis was carried out at the time of worm expulsion (self-cure). Just prior to the start of self-cure, a new mast cell population differentiated from cells with large nuclei and prominent nucleoli. Beginning on the 10th day of infection, mast cell numbers increased in an exponential fashion and reached a peak in the middle of the self-cure reaction 14 days after infection. At first the cells had few granules but their granule content subsequently increased and by day 14 some of them appeared to be mature. Mitoses were observed in granulated cells at all stages of the population expansion.

Differential counts showed that an increasing proportion of the mast cell population migrated intraepithelially to become globule leucocytes so that by day 14 the ratio of globule leucocytes to mast cells was 1/1. On subsequent days of infection, this ratio and the total population of granulated cells gradually diminished.

The results suggest that cell differentiation and division are responsible for the population increase. The high globule leucocyte/mast cell ratio points to an extensive release of amines from the granules during self-cure. The significance of this reaction in relation to antibody release from the mucosa and to worm expulsion is discussed.

Two antibody-producing cell types in four species

Both differentiating plasma cells and modified lymphocytes (lymphoplasmocytes) synthesize specific humoral antibody in rabbits, rats, mice and guinea-pigs. They do so during both primary and secondary responses, after subcutaneous injection of three enzymic antigens: horse radish peroxidase, glucose oxidase and alkaline phosphatase, administered as soluble or insolubilized proteins or alum precipitated or mixed with Freund's adjuvant.