Thoracic Duct Lymphocytes Research Articles

Induction of transplantation tolerance in rats by spleen allografts. I. Evidence that rats tolerant of spleen allografts contain two phenotypically distinct T suppressor cells.

We have examined suppressor cell activity in transplantation tolerant (TT) rats bearing vascularized spleen allografts in several different donor-recipient combinations. More than 60% of WAG (RT-1u) and 65% of AGUS (RT-1l) spleen allografts were permanently accepted when transplanted to AGUS and PVG (RT-1c) rats, respectively. All (WAG X AGUS)F1 to AGUS and (AGUS X PVG)F1 to PVG spleen allografts survived indefinitely. Unseparated LNC, TDL, and whole T cell or W3/25+, OX8- T cell populations obtained from AGUS rats bearing (WAG X AGUS)F1 spleens exhibited reduced mixed lymphocyte reaction (MLR) responses to the spleen donor, and to some extent to BN(RT1n) third-party stimulators, but responded normally to PVG.A(RT1a) stimulators. Coculture experiments demonstrated that lymph node cells (LNC) and thoracic duct lymphocytes (TDL) of TT rats contain RT1 specific suppressor cells. Furthermore, T cells isolated from all donor-recipient combinations contained two phenotypically distinct suppressor cell populations: a radiosensitive W3/25+, OX8- (Th/i) and a relatively radioresistant W3/25-, OX8+ (Ts/c). These Ts may be responsible for the maintenance of TT.

T cells can be cytotoxic without making interleukin 2: a model of separate pathways of induction.

The thoracic duct lymphocytes from rats previously injected with ultraviolet-light-irradiated allogeneic lymphocytes were grown for 4 days with alloantigen, with or without Con A-induced lymphokine factors, and then for 3 days with the lymphokines alone. They were then tested for their cytoxicity and for their capacity to make interleukin 2 (IL-2) in response to antigen. The results show that T helper cells specific for both class I and class II antigens of the major histocompatibility complex were removed from the circulation by the injection of ultraviolet-irradiated alloantigen. However, precursors of cytotoxic cells remained and appeared to lose their OX-19 markers during activation. We have interpreted the results by using a speculative model that involves separate pathways of induction to cytotoxicity and IL-2 synthesis. We propose that the OX-19 marker is associated with the interleukin 1 receptor and that the latter is required for the IL-2 production pathway but not for activation to cytotoxicity.

Natural killer cell activity in the rat. V. The circulation patterns and tissue localization of peripheral blood large granular lymphocytes (LGL).

Large granular lymphocytes (LGL) and T cells were separated from blood by centrifugation on discontinuous gradients of Percoll, were labeled with [3H]uridine or [111In]oxine, and were injected i.v. into syngeneic euthymic or athymic nude rats. The tissue distribution of these labeled cells was monitored for up to 24 hr after transfer by scintillation counting of tissue homogenates and autoradiography of tissue sections. In normal euthymic rats, the main sites of LGL localization were the alveolar walls of the lungs and spleen red pulp; however, they were not detectable in the major traffic areas of T lymphocyte recirculation, the spleen white pulp, and lymph nodes. Furthermore, the density of labeled LGL was very low in the small intestine, thymus, kidney, and liver, although on a per-organ basis, about 10% of the injected radioactivity was found in the liver by 24 hr post-injection. When 111In-labeled LGL were injected i.v. into rats with an indwelling thoracic duct cannula, they completely failed to enter the thoracic duct lymphocyte (TDL) population over an observation period of 6 days. This finding was markedly different from the results obtained with T cells and was consistent with the lack of natural killer and antibody-dependent cellular cytotoxicity activity observed among TDL, even in rats pretreated with the biological response modifier, poly I:C. LGL in athymic nude rats also failed to recirculate between blood and lymph. However, in contrast to normal euthymic animals, a significant increase in the localization of radiolabeled LGL to lymph nodes was observed in nude rats between 30 min and 24 hr. Taken as a whole, these findings define the areas within the lungs and spleen in which blood LGL normally localize, and clearly demonstrate that LGL do not normally recirculate between blood and lymph.

A monoclonal anti-HEBFPP antibody with specificity for lymphocyte surface molecules mediating adhesion to Peyer's patch high endothelium of the rat.

Cell surface molecules involved in lymphocyte adhesion to high endothelial cell venules (HEV) of Peyer's patches (PP) have been studied in the rat by using a mouse monoclonal anti-HEBFPP (1B.2) antibody. We previously showed that rat thoracic duct lymph contains a high endothelial cell binding factor termed HEBFPP, which in vitro blocks lymphocyte binding sites of HEVPP but not HEVLN. Monoclonal 1B.2 antibody was produced by fusing P3U1 myeloma cells with spleen cells of a mouse immunized with this material. Immunoprecipitation studies with 125I surface-labeled rat thoracic duct lymphocytes (TDL) showed that the antibody recognized an 80-kilodalton protein. This antigen was present in the majority of TDL, spleen, LN, and PP cells but was found on few (5 to 10%) thymus and bone marrow cells (indirect immunofluorescence). Treatment of TDL with 1B.2 antibody blocked their ability to bind in vitro to HEVPP; antibody treatment did not interfere with TDL adhesion to HEVLN. Analysis of 1B.2 antigen isolated from lymph and detergent lysates of TDL by antibody-affinity chromatography showed that this material had the capacity to block lymphocyte binding sites of HEVPP but not HEVLN. In contrast, material with such blocking activity was not isolated from detergent lysates of thymocyte, a population deficient in HEV-binding cells. The results indicate that the 1B.2 antigen is a component of the lymphocyte surface recognition structure mediating adhesion to HEVPP and provide further evidence that distinct adhesion molecules of rat TDL mediate interaction with high endothelium of LN and PP.

Differences in the recruitment of virgin B cells into antibody responses to thymus-dependent and thymus-independent type-2 antigens.

The bone marrow of mammals generate large numbers of B cells throughout life. Most of these have a short life span. The subject of this report is to investigate the extent to which newly formed virgin B cells can be activated by thymus-dependent (TD) and thymus-independent type 2 (TI-2) antigens carrying the hapten 2,4-dinitrophenyl. The experimental approach used chimeras made between congenic rats of different kappa immunoglobulin light chain allotype. Host (kappa la) rats were depleted of peripheral B cells by whole body irradiation but had B lymphopoietic capacity conserved by shielding the hind limbs. Their peripheral B cell pool was reconstituted by transfer of kappa lb thoracic duct lymphocytes from donors immunized previously with the TD carrier. This provides test animals where newly produced virgin B cells only express kappa la but where initially most peripheral B cells are kappa lb. The TD antigen tested was able to activated both virgin and memory B cells in the period immediately following immunization. However, long-term antibody production was attributable to repeated activation of memory B cell clones without further virgin B cell recruitment. By contrast, antibody evoked by the TI-2 antigen initially was almost exclusively due to activation of donor peripheral B cells. However, over a period following TI-2 immunization there was a progressive increase in the amount of host antibody produced with corresponding decline of the donor component of the response so that the host response was dominant by six weeks. Control experiments were conducted to show that these effects could not be explained by allotype or isotype-directed suppression. The cellular basis of these differences was investigated further by studying the rate of repopulation of different B cell compartments in these chimeras by newly formed host and mature donor B cells. The results indicate that the onset of host antibody production to the TI-2 antigen closely correlated with the appearance of host B cells in the marginal zones of the spleen, whereas good TD host anti-2,4-dinitrophenyl responses antedated the appearance of host B cells in this compartment. These results are discussed in relation to other data implicating marginal zone B cells in responses to TI-2 antigens.

胸管リンパ球の機能からみたリンパ節郭清に対する一考察

胸管リンパ球の機能からみたリンパ節郭清に対する一考察

Virgin B cell recruitment and the lifespan of memory clones during antibody responses to 2,4-dinitrophenyl-hemocyanin.

The extent to which B cells newly formed in the bone marrow contribute to primary and secondary B cell responses was investigated. This was assessed by constructing chimeras between congenic strains of rats differing in their kappa light chain allotype. Recipient animals received 800 cGy whole body irradiation with hind limb shielding to protect a proportion of their hemopoietic capacity. These rats then received 3 X 10(8) kappa allotype-marked thoracic duct lymphocytes from donors previously immunized twice with either dinitrophenylated spider crab (Maia squinada) hemocyanin (DNP-MSH) or MSH alone. The chimeras were immunized with DNP-MSH and the production of anti-DNP antibody of both donor and host origin was measured. In the period immediately after immunization both newly formed host virgin B cells and donor memory B cells gave rise to substantial proportions of the anti-DNP antibody. After this initial period, antibody production became sustained by activation of memory B cells only. The chimeras were reimmunized with DNP-MSH at 32 days after their first immunization. There was again evidence of a brief period of both virgin and memory B cell activation followed by memory B cell activation only. Donor B cell clones remained dominant in the established response throughout the 5 months each chimera was studied. The data are interpreted as indicating two phases of B cell activation. It is suggested that the first phase where both virgin and memory B cells are activated may be associated with antigen presentation on dendritic or interdigitating cells outside follicles. It is argued that the second phase where only memory B cells are activated is more likely to be associated with antigen on follicular dendritic cells.

胃がん患者におけるヒト胸管リンパ球のしゅよう認識とＩｎｔｅｒｌｅｕｋｉｎ‐２によるｋｉｌｌｅｒ細胞誘導の検討

進行胃癌患者より胸骨リンパ球 (TDL) を得, 末梢血リンパ球 (PBL) と比較しInterleukin-2 (IL-2) 添加培養前後での腫瘍細胞に対する細胞障害および亜群の変化を検討した.Fresh TDLは殺細胞性リンパ球を有していなかった (TargetがPLCの場合, Effector/Target (E/T) 比100: 1で1.1±1.1の% Lysisを示した) が, 粗IL-2添加培養にてPBLと同様allogeneic tumorに対して強い細胞障害性を示した (Target: PLC, E/T比100: 1で52.3±3.7の%Lysisを示した).亜群をみるとOKT8+, OKT11+, OKIal+, Leu7+, Leu11+細胞が増加した.大量のTDLを得られることより臨床応用への可能性が示唆された.

The roles of interdigitating cells and natural killer cells in the rapid rejection of allogeneic lymphocytes.

The fate of radiolabeled allogeneic thoracic duct lymphocytes injected into congenitally athymic, nude rats was followed by autoradiography and electron microscopy. The allogeneic cells entered the host lymphoid organs at a normal rate, but once inside the lymphoid tissue they were rapidly phagocytozed by interdigitating cells (IDC) situated in the lymph node paracortex and the splenic periarteriolar lymphoid sheaths. Neither host nor donor T cells were required to initiate phagocytosis, as purified donor B cells were also avidly ingested by the athymic host IDC. Compared with fully allogeneic cells phagocytosis of semiallogeneic donor cells was much less efficient. When natural killer cell activity was blocked by preinjecting the recipients with antibodies against natural killer cells (anti-asialo GM1 or MRC OX-8) phagocytosis of the allogeneic cells was strongly reduced. As IDC did not bind these antibodies, the finding indicates that natural killer cells were needed to discriminate between own and foreign lymphocytes and to kill the allogeneic cells, which were then ingested by surrounding IDC. This was further supported by the observation that dendritic, constitutively Ia+ cells from peripheral lymph, phenotypically identical to IDC, did not lyse or phagocytoze allogeneic lymphocytes in vitro.

SUPPRESSION OF ANTIGRAFT EMMUNITY BY PREIMMUNIZATION

Delayed-type hypersensitivity (DTH) against histocompatibility (H) antigens in mice, which normally arises after s.c. immunization, can be prevented by i.v. preimmunization with irradiated spleen cells carrying the relevant H antigens. We have previously shown that during the first week after i.v. preimmunization the nonresponsiveness is due to suppressor T lymphocytes. The induced state of nonresponsiveness, however, is long-lasting. In this study we investigated whether this long-lasting state of nonresponsiveness of DTH is associated with suppressor T lymphocytes or is caused by inactivation of the relevant clones of alloreactive T cells. This was done by parabiosis of nonresponsive and naive mice and by transfer of thoracic duct lymphocytes from nonresponsive mice, harvested at various intervals after the i.v. immunization. At a long interval after the i.v. immunization, the state of nonresponsiveness could still be transferred to syngeneic naive mice by parabiosis, as well as by transfer of thoracic duct lymphocytes. Selective elimination of the T cells from the latter by treatment with anti-Thy-1.2 plus complement prevented the transfer of the state of nonresponsiveness, indicating that suppressor T cells were involved.

Specific antibody-blocking activities in antilymphocyte globulin as correlates of efficacy for the treatment of aplastic anemia

Horse anti-human thoracic duct lymphocyte globulin (ATDLG) has been used successfully for the treatment of severe aplastic anemia, although not all lots have comparable efficacy. We have characterized the antibody specificities contained in one lot of Swiss ATDLG found to provide a response rate of 69% and another lot that provided only a 31% response rate. Antibody specificities were analyzed quantitatively by competitive inhibition assays with the use of a panel of fluorescein- conjugated murine monoclonal antibodies that recognize T cell antigens, common leukocyte antigens, and “la-like” antigens. Although there was wide variation in the amounts of individual antibody specificities within each lot, the effective lot of ATDLG contained an average of 2 1/2 times as much of each antibody specificity as the less effective lot. There were only two antibody specificities that differed remarkably from this pattern; and these deviations did not appear sufficient to account for the variation in ATDLG efficacy. It is possible that antibody specificities other than those tested were responsible for therapeutic efficacy. Alternatively, the data suggest that it might be possible to achieve improved results for the treatment of severe aplastic anemia with higher doses of less effective lots of ATDLG.

Specific Antibody-Blocking Activities in Antilymphocyte Globulin as Correlates of Efficacy for the Treatment of Aplastic Anemia

AbstractHorse anti-human thoracic duct lymphocyte globulin (ATDLG) has been used successfully for the treatment of severe aplastic anemia, although not all lots have comparable efficacy. We have characterized the antibody specificities contained in one lot of Swiss ATDLG found to provide a response rate of 69% and another lot that provided only a 31% response rate. Antibody specificities were analyzed quantitatively by competitive inhibition assays with the use of a panel of fluorescein-conjugated murine monoclonal antibodies that recognize T cell antigens, common leukocyte antigens, and “la-like” antigens. Although there was wide variation in the amounts of individual antibody specificities within each lot, the effective lot of ATDLG contained an average of 2½ times as much of each antibody specificity as the less effective lot. There were only two antibody specificities that differed remarkably from this pattern; and these deviations did not appear sufficient to account for the variation in ATDLG efficacy. It is possible that antibody specificities other than those tested were responsible for therapeutic efficacy. Alternatively, the data suggest that it might be possible to achieve improved results for the treatment of severe aplastic anemia with higher doses of less effective lots of ATDLG.

In vivo separation of two classes of T cells as determined by negative selection after the injection of UV-treated allogeneic lymphoid cells.

Negative selection occurred when gamma-irradiated lymphoid cells of rat strain PVG were injected intravenously into strain Fischer rats, which differ from PVG rats at the major histocompatibility complex. By 48 hr after injection, thoracic duct lymphocytes (TDL) from these animals failed to proliferate or generate cytotoxic T lymphocytes (CTL) in vitro in response to gamma-irradiated PVG lymphoid cells. Responses to cells of a third rat strain were unaffected. By about 6 days after antigen injection, positive selection had occurred, as shown by enhanced responses to gamma-irradiated PVG cells in the same assays. Ultraviolet-irradiated strain PVG populations were tested in the same way. They differed from gamma-irradiated PVG cells in that they failed to induce proliferation or stimulate CTL in vitro. TDL from Fischer rats injected with UV-irradiated PVG cells failed to proliferate or generate CTL in response to gamma-irradiated PVG cells in vitro. The CTL response of TDL from rats injected with UV-irradiated cells was restored by the addition of supernatant factor(s) from concanavalin A-stimulated lymphoid cells (ConA SnF). Therefore, CTL precursors did not undergo negative selection after injection of UV-treated cells. There was also no detectable positive selection 6 days after injection of UV-treated cells. These experiments show that it is possible to separate two populations of T cells in vivo by the injection of UV-irradiated allogeneic lymphoid cells. One population incorporates [3H]thymidine early in an allogeneic response in vitro, the other expresses cytotoxic activity only after the addition of ConA SnF in vitro. The first population can replace the requirement for ConA SnF by the CTL population.

Lymphocyte recognition of lymph node high endothelium. VII. Cell surface proteins involved in adhesion defined by monoclonal anti-HEBFLN (A.11) antibody.

Lymphocyte entry into lymph nodes (LN) and Peyer's patches (PP) occurs specifically at high endothelial cell venules (HEV). We previously isolated a high endothelial binding factor (HEBFLN) from rat lymph that blocked the lymphocyte binding sites of HEVLN but not HEVPP. In this study, mouse monoclonal anti-HEBFLN antibody (A.11) was used to investigate rat lymphocyte surface structures mediating adhesion to high endothelium. The A.11 antigen was expressed on the majority of thoracic duct lymphocytes (TDL), spleen, LN, PP cells, but was only detected on few (1 to 10%) thymus and bone marrow cells (indirect immunofluorescence). The treatment of TDL with the A.11 IgG blocked their ability to bind to HEVLN. This effect was specific, inasmuch as A.11 antibody did not block lymphocyte binding to HEVPP, and an anti-leukocyte-common antigen monoclonal antibody, OX1, did not block lymphocyte binding to HEVLN. In addition, the A.11 antigen isolated from the lymph and detergent lysates of TDL by antibody affinity chromatography had the capacity to block the lymphocyte binding sites of HEVLN but not HEVPP. Immunoprecipitation studies revealed that the A.11 antibody recognized the radioiodinated surface membrane proteins of TDL and TDL-derived T cells and B cells, which resolved with SDS-PAGE autoradiography into three polypeptides with relative m.w. of approximately 135,000, 63,000, and 40,000. We conclude that the A.11 antigen is a component of the lymphocyte surface recognition structure that mediates adhesion to high endothelial cells of rat peripheral lymph nodes.

Induction of natural killer cell activity of thoracic duct lymphocytes by polyinosinic-polycytidylic acid (poly(I:C)) or interferon

Natural killer (NK) cell activity of thoracic duct lymphocytes (TDL) was examined in normal mice and in mice treated with polyinosinic-polycytidylic acid (poly(I:C)) and interferon (IFN). TDL from mice treated with phosphate-buffered saline (PBS) expressed little or no NK cell activity against YAC-1 target cells at effector-to-target ratios of up to 200:1, even after in vitro treatment with murine L-cell IFN. In contrast, TDL from poly(I:C)- or IFN-treated mice expressed significant NK activity, which correlated with the significantly higher NK activity of splenocytes from these mice compared to the NK activity of splenocytes from PBS-treated mice. These data indicate that although TDL from normal mice express no detectable NK cell activity, NK cell activity can be induced in TDL by in vivo treatment with poly(I:C) or IFN.

Physiology of B cells in mice with X-linked immunodeficiency. I. Size, migratory properties, and turnover of the B cell pool.

In terms of certain immune functions and density of surface IgM, B cells from xid mice are often viewed as the equivalent of the immature (Lyb-5-) B cell subset of normal adult mice. In this paper we examine xid B cells with regard to certain physiologic functions, including homing to the lymphoid tissues, recirculation, and turnover. Xid mice were found to possess about one-third of the total number of B cells found in normal mice. This applied irrespective of whether one examined the spleen, lymph nodes, or outputs of B cells in thoracic duct lymph. In terms of migration to spleen, lymph nodes, and Peyer's patches, capacity to recirculate from blood to thoracic duct lymph, and turnover, xid B cells proved to be indistinguishable from normal spleen or thoracic duct B cells. Within these parameters, most xid B cells closely resemble the normal mature long-lived population of B cells residing in the recirculating pool of normal mice. Because xid B cells are functionally quite different from normal mature B cells, it seems reasonable to view xid B cells as an abnormal population not represented in normal mice.

Lymphocyte recognition of lymph node high endothelium. VI. Evidence of distinct structures mediating binding to high endothelial cells of lymph nodes and Peyer's patches.

Lymphocytes migrate from blood into lymph nodes (LN) and Peyer's patches (PP) of rats specifically at segments of venules lined by high endothelium (HEV). We previously identified and isolated a lymphocyte surface component termed high endothelial binding factor (HEBF) that appears to be involved in lymphocyte adhesion to high endothelial cells of LN. HEBF has also been isolated from thoracic duct lymph and is antigenically related to the cell surface component. Soluble HEBF derived from detergent lysates of thoracic duct lymphocytes (TDL) or directly from lymph has affinity for HEVLN in vitro, and is able to block sites where lymphocytes would normally attach. In the present study, lymphocyte binding sites of HEVLN and HEVPP were investigated through the use of lymph-derived HEBF and rabbit antibody to this factor. The results show that treatment of rat TDL with anti-HEBF Fab did not block binding to HEVPP, even though adhesion to HEVLN was reduced by 80% or more. Similarly, HEBF isolated by anti-HEBF F(ab')2 affinity chromatography blocked lymphocyte binding sites of HEVLN but not HEVPP. This material is therefore designated HEBFLN, and antibody to it is designated anti-HEBFLN Ig. Fractionation of thoracic duct lymph revealed that it contained an antigenically distinct component, HEBFPP, which blocked lymphocyte binding to HEVPP but not to HEVLN. Lymph components precipitating between 40 and 60% (NH4)2SO4 saturation contained both factors, which were separated from the bulk of lymph proteins by DEAE-Sepharose chromatography and then from each other by fractionation on the anti-HEBFLN F(ab')2-Sepharose column. The unbound fraction from this column contained HEBFPP, which was then partially purified by CM-Sepharose filtration. HEBFPP appeared to be a glycoprotein because it was destroyed by trypsin, bound to lentil lectin, and was eluted with alpha-methyl-mannoside. Together, the results demonstrate the existence of two antigenically distinct species of HEBF, and imply that lymphocyte binding sites of HEVLN and HEVPP are structurally different. We interpret the results to mean that distinct high endothelial adhesion molecules on lymphocytes mediate their entry into LN and PP.

Mucosal mast cells are functionally active during spontaneous expulsion of intestinal nematode infections in rat.

Infestation of the gastrointestinal tract by parasitic nematodes is invariably associated with mucosal mastocytosis, which is a thymus-dependent phenomenon in parasitized rats, and is adoptively transferable with a T cell-enriched population of thoracic duct lymphocytes. When derived by in vitro culture, mucosal mast cells (MMC) arise from a bone marrow precursor after stimulation by T cell-derived factors. In rats infected with the nematode Trichinella spiralis, mucosal mastocytosis is temporally associated with the immune expulsion of the adult worms whereas in the case of Nippostrongylus brasiliensis, mastocytosis is frequently observed to occur after worm expulsion has been completed. Consequently, there has been doubt as to whether MMC are active and serve a functional role in the expulsion of rat intestinal nematodes. MMC contain and secrete a neutral proteinase, rat mast cell protease II (RMCP II); detection and assay of secreted RMCP II therefore provides a direct measurement of MMC activity. Here we describe the release of this enzyme into the blood of rats infected with N. brasiliensis or T. spiralis. Our results show that the systemic secretion of RMCP II coincides with the immune expulsion of these nematodes, demonstrating clearly for the first time that rat MMC are functionally active during the immune elimination of primary nematode infections.

Histamine-releasing activity: IV. Molecular heterogeneity of the activity from stimulated human thoracic duct lymphocytes

Previous studies with the lymphokine, histamine-releasing activity (HRA), showed that HRA consisted of a heterogeneous group of molecules. The possibility of using thoracic duct lymphocytes (TDL) as a source of large quantities of HRA has been investigated. Antigen-stimulated TDL synthesize and release HRA in quantities similar to an equivalent number of peripheral blood lymphocytes (PBL). Streptokinase (SK) antigen routinely caused TDL to produce HRA ~ 15,000 Da. In contrast, staphylococcus enterotoxin B (SEB) induced the formation of a heterogeneous mixture of HRAs with apparent molecular weights of 50,000 and 15,000. Two peaks of activity (HRA I and II) were recovered when the supernatant from SK-stimulated TDL was subjected to ion-exchange chromatography. Interestingly, basophil chemotactic activity (BCA) was also eluted in these two peaks. Although interferon (IFN) is also released by antigen-stimulated TDL, the nonidentity of IFN and HRA was established by fundamental differences in Chromatographic properties and specific antisera to IFN. In contrast, these studies suggest that HRA and BCA may be present on the same molecular entity.

Homing of germinal-center cells into germinal centers of lymph node via afferent lymphatics

Affinity of lymphoid cells for the microenvironment of germinal centers (GC), as detectable in transfer experiments by rapid homing in spleen GC from the blood, is a capacity expressed by only a subset of lymphoid cells, in particular by those constituting a GC. However, when introduced into the blood stream, these cells do not home into GC of lymph nodes and gut-associated lymphoid tissues. To investigate further this homing inability for high endothelial venule (HEV)-containing lymphoid tissues, GC cells isolated from donor rabbit appendix were labeled in vitro with 3H-leucine and injected into an afferent lymph vessel of recipient popliteal lymph nodes. Draining lymph nodes were removed 15 min to 24 h after cell administration and prepared for radioautography. For reference, the migration of cells isolated from Peyer's patches and thoracic duct lymph was also studied. By use of appendix GC cells, large numbers of labeled cells were found to migrate into GCs of the outer cortex centripetally, i.e., from the subcapsular sinus through the lymphocyte corona into the GC proper. The same was observed for cells from Peyer's patches, although in smaller numbers. Thoracic duct lymphocytes were only localized in the lymphocyte corona and the deep cortex. Thus, appendix GC cells and a subpopulation of cells from Peyer's patches can reach lymph node GC, but only when administered intralymphatically.(ABSTRACT TRUNCATED AT 250 WORDS)