Surface markers on lymphocytes of multiple sclerosis patients.

Peripheral blood lymphocytes of twenty-two multiple sclerosis (MS) patients and thirty-five healthy controls were examined for the presence of surface markers characteristic for B lymphocytes (surface immunoglobulin, receptor for C3 (EAC), reporter for Fc (EA) and the spontaneous rosette-forming capacity characteristic of T cells. The results obtained indicate that the number of B and T cells in MS is similar to controls, as evaluated by the presence of surface immunoglobulin and E rosette-forming capacity. However, a statistically significant reduction in the percentage of lymphocytes bearing C3 receptors has been found in MS patients. It might have resulted from a reduction in the lymphocyte population bearing C3 receptor but no surface immunoglobulin. The EA rosette test revealed the greatest difference between the groups. The difference indicated a reduction in the density of the receptor for 7S Fc on lymphocytes from MS patients. The results obtained are consistent with the hypothesis of an immune deficit in multiple sclerosis.     

Small lymphocytes in peripheral lymphoid tissues of nude mice. Life-span and distribution.

The distribution of small lymphocytes according to life-span in the peripheral lymphoid tissues of the mouse mutant "nude" has been studied by means of auto-radiography and scintillation counting to evaluate the localization of B lymphocytes with varying life-span. The vast majority of the lymphocytes in this congenitally athymic mouse are relatively long-lived, although few cells live for 6 weeks or more. Differences in labelling percentages of blood, spleen and lymph node lymphocytes indicated a production of lymphocytes with a short residence time in the spleen. A similar production was not seen in the lymph nodes. While the lymphocytes in the spleen were evenly distributed according to life-span, the paracortical lymphocytes in lymph nodes were found to have a generally shorter life-span than those of the cortex, in opposition to findings in normal mice. The cortical cells which were by far the most numerous in the lymph nodes seemed to be more sessile than para-cortical lymphocytes. The life-span of these latter cells are comparable to those of thoracic duct lymphocytes, and the scarcity of cells in the paracortex reflects the small number of recirculating lymphocytes in nude mice.     

Surface markers on lymphocytes leaving pig lymph nodes.

Mesenteric lymph nodes of normal young pigs were perfused in vitro at physiological temperature. Cell-free perfusion medium was pumped into the artery for more than 2.5 hr, and lymphocytes were continuously released into the venous effluent. Recirculating lymphocytes emigrate from pig lymph nodes by entering the blood vasculature directly and not via efferent lymphatics. The presence of lymphocytes in paracortical venular walls after 2 hr of perfusion with new medium suggests that these are the sites of emigration. The rate of emigration of lymphocytes from mesenteric lymph nodes was estimated to be 6 X 10(7)/hr. Study of the lymphocyte populations emerging from the perfused lymph nodes showed that B lymphocytes and E-rosette forming T lymphocytes, but almost no Null lymphocytes, are involved. While the proportion of B lymphocytes remained constant during the perfusion period, E-rosette forming lymphocytes increased significantly. Lymphocyte subpopulations differ profoundly in their capacity to migrate through lymph nodes.     

Surface markers of blood lymphocytes in bronchial carcinoma

The proportion of autologous rosette-forming, i.e. autoerythrocyte-binding, T-lymphocytes, was studied in 34 patients with untreated, operable bronchial carcinoma. The number of autorosettes in patients with bronchial carcinoma was considerably below the mean value for the normal control group. In patients with metastatic involvement of the regional lymph nodes at the time of surgery the reduction in the number of autorosettes was still more marked. On the 10th postoperative day after resection of the tumour and in case of remission five months after surgery, the number of autorosettes showed a significant rise approximating the normal value. The distribution of sheep-E-rosette-forming and of the "active-early" T-lymphocytes was also studied. On the evidence of the results, the number of autorosette-forming lymphocytes lends itself to a follow-up of bronchial carcinoma by early demonstration of remissions or recurrences.     

Surface markers of axolotl lymphocytes as defined by monoclonal antibodies.

In an attempt to identify urodele amphibian lymphocyte subpopulations by their surface markers, we prepared hybridomas from BALB/c mice spleen immunized with axolotl (Ambystoma mexicanum) blood and splenic leucocytes and purified immunoglobulins. Sixty-five hybridomas were selected and subsequently subcloned. Among numerous monoclonal antibodies (mAbs) thus obtained, four mAbs were extensively characterized by immunoblotting, single and double fluorescence and immunohistology. MAb 34.38.6 recognizes polypeptides between 65,000 and 72,000 MW and labels in immunofluorescence nearly all thymocytes, 60-63% splenic lymphocytes of normal animals but only 9% splenic lymphocytes in thymectomized animals. MAb 19.14.2 reacts with a 98,000 MW protein and labels a restricted lymphocyte population in thymus (52-77%) and spleen (20-25%). The immunohistological study demonstrates that 34.38.6 and 19.14.2 label most thymocytes and a large proportion of spleen leucocytes including lymphocytes, granulocytes and macrophages. In addition, 19.14.2 labels some large interdigitating cells in thymic epithelial areas and splenic cords. MAbs 33.45.1 and 33.101.2, respectively, recognize heavy (72,000-88,000 MW) and light (20,000-27,000 MW) axolotl immunoglobulin chains. They do not react with thymocytes but label a splenic lymphocyte population not labelled by mAb 34.38.6. The proportion of surface immunoglobulin-positive (sIg+) lymphocytes in spleen is not altered by thymectomy. MAb 33.101.2 labels 40-48% of splenic lymphocytes, 33.45.1 stains only 14% of these same cells. This suggests some interesting heavy-chain isotypic differences in axolotl. For the first time in urodele amphibians, mAbs differentiate T-like and B-like lymphocyte populations by their membrane markers. This will allow further analysis of the axolotl immune system.     

Distribution of porcine CD4/CD8 double-positive T lymphocytes in mucosa-associated lymphoid tissues.

The present study describes the distribution of CD4/CD8 double-positive (DP) T cells in lymph nodes and mucosa-associated lymphoid tissues of pigs at 6-7 months of age. Proportions of lymphocytes isolated from peripheral, bronchial and mesenteric lymph nodes expressing CD4 and/or CD8 molecules were similar and ranged from 10-13% CD4/CD8 DP cells, 25-27% CD4 single-positive (SP) cells, and 27-32% CD8 SP cells. Mucosa-associated lymphoid tissues had significantly smaller proportions of CD4+ and/or CD8+ T cells than lymph nodes and CD4/CD8 DP cells accounted for a larger proportion of the total CD4+ lymphocytes than in lymph nodes. Compared to the lymph nodes, the predominant CD4+ and/or CD8+ T-cell subset in tonsils was the CD4/CD8 DP population (18%), because of both a higher proportion of these cells and a lower proportion of CD4 SP (12%) and CD8 SP (14%) lymphocyte subsets. Jejunal Peyer's patches were comprised of 12% CD4 SP, 28% CD8 SP and 10% CD4/CD8 DP lymphocytes. In contrast, the mid-section of the continuous Peyer's patch in the ileum contained 7% CD4 SP, 8% CD8 SP and 4% CD4/CD8 DP lymphocytes. The distribution of T lymphocytes in porcine mucosal lymphoid aggregates agrees with the reported correlation between high and low rates of lymphocyte entry into these tissues and the abundance or scarcity of T cells, respectively. Defining the role of CD4/CD8 DP lymphocytes and their unique distribution in mucosa-associated lymphoid tissues in the pig may reveal novel T-cell-mediated regulatory pathways.     

Differential migration of in vivo primed B and T lymphocytes to lymphoid and non-lymphoid organs

Our study describes tissue-specific migration of T and B cells during a localized anti-viral immune response. After mouse mammary tumor virus (MMTV) injection, B lymphocytes of the draining lymph node become infected and present a retroviral superantigen to CD4(+) T lymphocytes. Infected B cells receive superantigen-mediated help in a fashion comparable to classical immune responses. To investigate the fate of T and B lymphocytes that had interacted via cognate help in the same peripheral lymph node microenvironment we adoptively transferred them into naive recipients. Here we show that MMTV-infected B cells and superantigen-stimulated T cells were programmed to migrate to distinct sites of the body. Plasmablasts but not T cells migrated to the mammary gland and activated alpha4beta1 integrins were found to have a crucial role in the migration to the mammary gland. In contrast, T cells had a much higher affinity for secondary lymphoid organs and large intestine.This demonstrates that upon antigen-driven B and T lymphocyte interaction in the local draining lymph node a subset-specific homing program for B and T lymphocytes is induced.     

Surface markers of lymphocytes in the snake, Spalerosophis diadema. I. Investigation of lymphocyte surface markers.

A specific antiserum was raised in rabbits against thymocytes from snakes, Spalerosophis diadema, and was absorbed repeatedly with snake erythrocytes and kidney cells. In complement-dependent cytotoxicity assays, the absorbed anti-thymocyte serum (ATS) was, at any given dilution, cytotoxic to Sp. diadema thymocytes > peripheral blood lymphocytes (PBL) > spleen cells and could be titrated to a plateau defining a population of about 98% of thymocytes, 80% of PBL and 72% of spleen cells. Antiserum directed against snake immunoglobulins was obtained by injecting rabbits with gamma-globulins separated from snake serum by DEAE-cellulose filtration. the anti-gamma globulin serum was absorbed with snake erythrocytes, and in indirect membrane immunofluorescence stained no thymocytes while reacted with about 15% of PBL and 29% of spleen lymphocytes up to a 1:8 dilution. Fluorescence of positive cells was distributed in spots, patches or caps; cap formation could be inhibited by maintaining the immunofluorescence test at +4 degrees. In each of six separate experiments performed during spring, the percentage of lymphocytes which reacted with anti-snake gamma-globulin serum complemented the percentage of cells recognized by ATS. It was shown, furthermore, that about 3%, 8% and 21% of lymphocytes from thymus, peripheral blood and spleen, respectively, possess a receptor for 2-mercaptoethanol-insensitive antibody-sheep erythrocyte complexes. The results indicate that lymphocyte structural heterogeneity exists in reptiles.     

Histopathology of lymphoid organs in experimental leishmaniasis.

Hamsters (Mesocricetus auratus) were inoculated with L. (L.) chagasi and killed on days 7, 15, 30, 45 and 60 after infection. The lymphoid organs developed initial proliferation of the B lymphocyte zone with recovery by the 60th day group when pyroninophilic cells were prominent. The T lymphocyte area showed a progressive selective decrease of lymphocytes and cellular density with cellular pleomorphism including macrophages, plasma cells and reticular cells. The mean volume of the white pulp increased with the lymphoid follicle hyperplasia but returned to its initial level by day 60. The main red pulp change was marked hyperplasia of the phagocytic mononuclear cells containing parasites from the 30th day of infection onward. These changes are compatible with the humoral and cellular immunoresponse found in patients with visceral leishmaniasis (VL).     

Circulation and migration of small blood lymphocytes in the rat. I. Kinetics of lymphocyte circulation in the lymphoid organs.

Seventy male Wistar rats were the recipients of labeled small lymphocytes (1.5 X 10(7) each) collected from the peripheral blood of syngeneic donors. The migrating labeled lymphocytes were traced in the various organs 1 to 60 minutes following their transfusion. Lymphoid organs and liver were processed for extraction of labeled nucleotides and for radioactivity assay. The purpose of this work was to study the dynamics of the circulation of the small lymphocytes between blood and lymphoid system. This study was done before equilibrium between these two compartments was reached. The result of this work showed that the small blood lymphocytes recirculate continuously between peripheral blood and the lymph node with duration less than 3 minutes per cycle. In a lymph node, this circulation is 80 times more efficient than the circulation via the thoracic duct lymph.     

Secretory immune responses in ageing rats. II. Phenotype distribution of lymphocytes in secretory and lymphoid tissues.

The distribution of lymphocyte phenotypes was examined in various tissues from weanling (21-35 days), adult (3-4 months), mid-life (10-12 months) and senescent (18-20 months) rats. Lymphoid tissues included peripheral blood, spleen, cervical, mesenteric and inguinal lymph nodes. Tissues associated with secretory immune responses were also examined, including submandibular and parotid salivary glands, extraorbital lacrimal glands and Peyer's patches. IgA, IgG and IgM B cells were determined by surface Ig staining. Total T cells (W3/13), T helper/inducer (Th) (W3/25), T suppressor/cytotoxic (Ts) (OX8) and immature T cells (Thy 1.1; OX7) were also evaluated. IgG B cells were significantly decreased in lymphoid tissues from the senescent rats, while the weanling group exhibited decreased levels of all three B-cell isotypes compared to adult animals. IgA B cells were significantly decreased in the secretory tissues of the senescent rats, while IgM B cells were increased in both the weanling and senescent groups. Total T-cell percentages were unaffected by ageing in any of the tissues. The only consistent alteration in the lymphoid tissues was a decrease in Thy 1.1-positive cells in the older groups compared to the weanling group. A decreased Th cell percentage was demonstrated in the salivary and lacrimal glands of the weanling and senescent groups. Decreases in Th/Ts ratios, as well as decreased numbers of plasma cell precursors in the secretory tissues of the aged rats, suggests that alterations in normal secretory immune responses may be expected to accompany the ageing process.     

Proliferation of macrophage subpopulations in the adult rat: comparison of various lymphoid organs

Adult male Lewis rats received a single intravenous injection of 5-bromo-2'-deoxyuridine (BRDU) to label all proliferating cells in the S-phase of the cell cycle. Various lymphoid organs were removed 1 and 24 hr after injection to assess local proliferation and migration of newly formed cells, respectively. In cell suspensions, surface staining was performed for macrophage subsets (ED1, ED2, ED3), and the DNA label BRDU was detected by a monoclonal antibody. Local proliferation of ED1+ macrophages occurred in all organs investigated with the exception of the blood. Bone marrow outweighed the other organs by far; in addition to the proliferating ED1+ promonocytes, the bone marrow also contained BRDU-labeled ED2+ macrophages. Newly formed ED1+ monocytes migrated into lymphoid organs such as the mesenteric lymph nodes and spleen where they comprised about 90% of newly formed macrophages. In the spleen, ED3+ macrophages seemed to be renewed by local proliferation, whereas in the mesenteric lymph nodes these cells were replaced by immigration. The heterogeneity of macrophages was further demonstrated by the different renewal of splenic macrophages. ED1+ and ED3+ cells were replaced in a matter of days, whereas it would probably take several months to renew ED2+ cells.     

Surface immunoglobulin on rabbit lymphoid cells. V. Ultrastructural distribution of b4 allotypic determinants of thymus, lymph node and bone marrow lymphocytes.

An indirect immunoferritin-labeling technique is used to localize cell surface immunoglobulin (Ig) allotypic determinants on rabbit lymph node, bone marrow and thymus lymphocytes. 47% of the lymph node cells, 62% of bone marrow small lymphocytes and less than 1% of thymic lymphocytes, are positive for surface Ig. Two Ig-positive lymph node lymphocyte populations which differ in fine structure are identified but both cell types express similar amounts of surface Ig (7,000-28,000 Ig molecules per cell). Bone marrow small lymphocytes make up only 9% of the total cell population and express less surface Ig (ca. 3,000-12,000 molecules Ig per cell) than most Ig-bearre described and both are essentially negative for surface Ig using this labeling technique.     

Ontogeny of primary lymphoid organs and lymphoid stem cells

Cells of the immune system go through a series of important developmental steps that begin early in embryonic life and include, first, the various waves of hemopoietic-cell production in the embryo and, second, the homing of these cells to the hemopoietic organs, which are the sites of hemopoiesis and lymphopoiesis in embryonic and adult life. The avian embryo is an important model for investigating these early steps; and this paper presents a comprehensive review of the work done on the early ontogeny of the avian immune system.     

Surface markers on human activated T lymphocytes. III. High-affinity E-rosette receptors

High-affinity E-rosette receptor (EhR) is suggested to be an activation marker of human T lymphocytes. The present study has been undertaken to estimate the dependence of EhR expression upon the T cell activation. To this aim the expression of EhR on T cells stimulated with PHA was examined. Nonsynchronized and arrested in G1 phase of cell cycle cultures of T lymphocytes were employed. The kinetics of expression of either de novo induced or reexpressed EhR was estimated by using two T cell subsets (originally EhR- and EhR+). In accordance with opinion of others, our results have shown that EhR is an activation marker of human T cells. Moreover, we have found that EhR is the marker of early and late activation stage because: its expression is induced in G1 phase of cell cycle, it continues to increase with the time of mitogen stimulation and the maximal level of EhR expression coincides with the time of the maximal RNA and DNA synthesis. Both induced de novo and reexpressed Eh receptors display the same expression kinetics.     

The distribution of cytoplasmic immunoglobulin containing cells over various lymphoid organs of congenitally athymic (nude) mice as a function of age.

The distribution of cells containing cytoplasmic immunoglobulin (C-Ig cells) over various lymphoid organs was studied in congenitally athymic (nude) mice as a function of age. The C-IgM, C-IgG and C-IgA cells were enumerated in spleen, bone marrow, mesenteric lymph node and Peyer''s patches of nude mice and their heterozygous littermates of 6, 40 and 100 weeks of age. In the nude as well as in the heterozygous mice an age-related shift was observed in the localization of the C-Ig cells. In young mice of both groups the majority of these cells resided in the spleen, whereas in adult and old mice the bone marrow was found to be the major C-Ig cell organ, indicating that this shift is not dependent on the presence of the thymus. In young and adult nude and heterozygous mice C-Ig cell numbers in the spleen were comparable, whereas C-Ig cell numbers in the other lymphoid organs were higher in the heterozygous mice than in the nude mice. The total C-Ig cell number in young and adult nude mice was lower than in heterozygous mice of the same age, whereas in old nude mice they were as high as in heterozygous mice of the same age, indicating a retarded development of the immunological activity in nude mice. C-Ig cells in nude mice were almost exclusively of the IgM class, although in the bone marrow of the oldest animals also a substantial number of C-IgG and C-IgA cells was observed. Our finding that nude mice can live up to at least two years of age indicates that the age-related deterioration of the thymus-dependent limb of the immune system is not the cause of ageing, but rather a consequence of it.     

Neutrophils in secondary lymphoid organs

Neutrophils are traditionally considered short‐lived, circulating innate immune cells that are rapidly recruited to sites of inflammation in response to infectious and inflammatory stimuli. Neutrophils efficiently internalize, kill or entrap pathogens, but their effector molecules may cause collateral tissue damage. More recently, it has been appreciated that neutrophils can also influence adaptive immunity. Lymph nodes (LNs) are immune cell‐rich secondary lymphoid organs that provide an ideal platform for cellular interaction and the integration of immunological information collected from local tissues. A variety of peripheral stimuli promote neutrophil migration to draining LNs via blood or lymphatics, utilizing differing molecular cues depending on the site of entry. Within LNs, neutrophils interact with other innate and adaptive cells. Crosstalk with subcapsular sinus macrophages contributes to the control of pathogen spread beyond the LN. Neutrophils can influence antigen presentation indirectly by interacting with DCs or directly by expressing major histocompatibility complex (MHC) and costimulatory molecules for antigen presentation. Interactions between neutrophils and adaptive lymphocytes can alter B‐cell antibody responses. Studies have shown conflicting results on whether neutrophils exert stimulatory or inhibitory effects on other LN immune cells, with stimulus‐specific and temporal differences in the outcome of these interactions. Furthermore, neutrophils have also been shown to traffick to LNs in homeostasis, with a potential role in immune surveillance, antigen capture and in shaping early adaptive responses in LNs. Understanding the mechanisms underpinning the effects of neutrophils on LN immune cells and adaptive immunity could facilitate the development of neutrophil‐targeted therapies in inflammatory diseases.