Prolonged antigen half-life in the lymphoid follicles of specifically immunized mice

The kinetics of clearance of ¹²⁵I from the popliteal lymph nodes and feet of human serum albumin (HSA)-immunized mice was studied following the injection of [¹²⁵I]-HSA into the hind footpads. Antigen was cleared from both locations rapidly for the first few days. The antigen half-life (T½) during this period was only a matter of hours. By the end of the first week, however, the rate of clearance in both sites had changed markedly. The antigen T½ in the node between the first and sixth week was 8.1 weeks (95% confidence interval between 5.1 and 20 weeks) and the antigen T½ in the foot was 6.1 weeks (95% confidence interval between 3.7 and 16.6 weeks). There was, however, about twenty times more radioactivity in the feet than in the popliteal nodes. Autoradiography of popliteal lymph nodes revealed that initially antigen was trapped in the medulla, subcapsular sinus, superficial cortex and around lymphoid follicles. During the first few days antigen was cleared from all sites except the follicles. The radioactivity initially trapped in the medulla, subcapsular sinus, and superficial cortex appeared to have been associated with macrophages. Studies with peritoneal macrophages indicated an antigen T½ in these cells of 2 h (95% confidence interval between 1.5 and 3 h). The initial rapid clearance of antigen trapped and catabolized by macrophages and the long-term retention of antigen in the follicles is probably attributable to trapping and retention by follicular dendritic cells. The large pool of antigen trapped in the foot did not appear to serve as a depot to replace antigen degraded in the node, since amputation of the foot did not alter the level of antigen retained in the node. The long antigen T½ in the lymph node follicles indicates that antigen is available in the lymph node to play a role in the maintenance and regulation of immune responses for many months or even years.     

Studies on the afferent and efferent lymph of lymph nodes draining the site of application of fluorodinitrobenzene (FDNB)

Peripheral lymph (afferent to the popliteal node) or intermediate lymph (efferent from the popliteal or prefemoral node) was collected from unanaesthetized sheep before and after painting the skin of the drainage area with a 10 per cent solution of fluorodinitrobenzene (FDNB) in acetone. In some experiments FDNB labelled with tritium ([³H]FDNB) was used.The changes in the cell population of efferent lymph from nodes thus stimulated were generally similar to those which occur following stimulation with conventional antigens, i.e., between 90–120 hours later many large basophilic lymphoid blast cells (immunoblasts) appeared in the lymph and specific antibody appeared in the lymph plasma.Studies with [³H]FDNB showed that although some of it appeared in afferent lymph almost immediately after application, substantial amounts were not present usually until 20 hours or so later. All of the FDNB in the afferent lymph was bound to soluble proteins in the plasma and none was found in association with the lymph cells. Apparently, this protein bound FDNB was inefficiently phagocytosed in the regional node because much of it passed through the node so that it could be recovered in the efferent lymph for 100 hours or more following the original application.It was concluded that skin sensitizing chemicals of the FDNB class are transported to the node after they have combined with soluble proteins that enter the lymph; in the combined form they behave like other soluble protein antigens and provoke similar cellular responses in the regional tissue.     

Lymph node localization and whole body distribution of radioiodinated encephalitogenic polypeptide in guinea-pigs

A bovine encephalitogenic polypeptide (BEP) labelled with radioiodide retained its capacity to induce experimental encephalomyelitis (EAE). Guinea-pigs were injected with ¹²⁵I BEP in Freund's complete adjuvant (FCA), to study changes in the architecture and the distribution of radioactivity in draining lymph nodes, and the amount of radioactivity in various organs.

After injection of BEP in FCA the lymph node rapidly enlarged. Within 48 hr there was depletion of lymphocytes, the enlarging lymphoid follicles had become confluent and there was proliferation of large `epithelioid' cells throughout the node. At 5 days the lymph node architecture was disorganized and lymph follicles with germinal centres could not be recognized; similar but less pronounced changes were present in regional nodes. By contrast, after injection of flagellin in FCA, there were numerous lymphocytes, plasmablasts and pyroninophilic cells, germinal centres were prominent, and the architecture was preserved.

From 0·5 to 0·8% of the total injected radioactivity was concentrated in the popliteal lymph node 2–5 days after injection of ¹²⁵I BEP in FCA. No radioactivity was concentrated in the node after injection of ¹²⁵I BEP without FCA, and animals thus immunized did not develop encephalomyelitis.

The popliteal lymph node was examined by autoradiography after injection of ¹²⁵I BEP in FCA. At 24 hr radioactive encephalitogen associated with droplets of adjuvant was present mainly in the peripheral sinus and at 48 hr encephalitogen–adjuvant droplets were deposited randomly throughout cortex and medulla. These droplets appeared to represent sites where lymphoid cells acquired their capacity for pathogenic reactivity with their target antigen in the central nervous system.

     

The migration of lymphocytes from bone marrow to popliteal lymph nodes demonstrated by selective bone marrow labeling with 3H-thymidine in vivo

Guinea pig popliteal lymph nodes were examined by DNA radioassay and radioautography following the selective labeling of tibial and femoral marrow cells by intramyeloid injections of ³H-thymidine. The DNA radioactivity of the node increased for the first four days and at four to seven days exceeded that seen after an intraperitoneal injection of the same total dose of ³H-thymidine, indicating an export of radioactivity from the labeled marrow to the node. Simultaneously, radioautographic sections of the node revealed labeled cells indicative of an origin from marrow precursors. Small lymphocytes constituted 60–90% of the labeled cells and reached maximal numbers at four to six days. Most of them were observed in the cortex, including the subcapsular sinus, primary follicles, mantle zones around germinal centers, and the lumen and walls of post-capillary venules. However, the highest labeling indices of small lymphocytes occurred in the medulla, including the medullary cords, medullary sinuses and efferent lymphatic vessels. Labeled large mononuclear cells, including large lymphoid cells, monocytes and large blast cells, were confined almost exclusively to the cortex. A small number of labeled plasma cells was observed in the medullary cords. It is concluded that newly-formed bone marrow lymphocytes migrate continuously into immunologically quiescent lymph nodes and become widely distributed throughout the cortex and medulla, while some enter the recirculating small lymphocyte pool.     

Role of the Popliteal Lymph Node in Infection with Mycobacterium marinum of the Hind Footpad of the Mouse, and Source of the Cells that Characterize the Process

We examined the possibility that the popliteal lymph node serves as the source of the lymphocytes that, together with macrophages, characterize Ihc lesion produced by infection with Mycobacterium marinum in the hind footpad of Ihc mouse. Naive mice were partially protected against challenge with M. marinum in the hind footpad by intravenous infusion of lymphoc) its harvested from the popliteal nodes of donor mice infected with M. marinum 7 days earlier. Lymphocytes harvested from the popliteal nodes of infected donors, labelled in vitro with ³H-uridine, and infused intravenously into naive mice that were immediately challenged in the hind footpads with M. marinum, localized in the popliteal nodes of the recipient mice but nol in the footpad lesions. Lymphocytes harvested from the spleens of naive donors and labelled in vitro appeared to home to the popliteal nude draining the M. marinum-infected footpad. Thus, the primary rule of the popliteal lymph node appeared to be passive trapping of the lymphocytes brought to it by the circulairon or afferent lymphatics. We then tried lo locate the sources of bolh lymphocytes and macrophages that characterize the lesion. Temporary occlusion of the abdominal aorta prevented labelling by intravenously infused ³H-thymidine (³H-TdR) of the mononuclear cells of both footpad lesion and popliteal node. Temporary occlusion of the left common iliac artery during ³H-TdR infusion prevented immediate labelling on the ipsilateral side. After 24 and 48 h, however, small numbers of labelled lymphocyles were found in the left hind footpad lesion. Amputation of the right leg at the hip joint, but run right poplitial lymphadenectomy, performed immediately after re-estublishment of patency of the left common iliac artery, prevented the late influx of labelled lymphocytes into the lesion of the left hind footpad. Thus, the chief source of both the lymphocytes and the macrophages of the footpad lesion appeared lo be the lesion ilself.     

Lymphatic mast cell response and effect of compound 48/80 on popliteal lymph node reaction in rats following intracutaneous injection ofStaphylococcus aureus

To investigate the significance of mast cells in the popliteal lymph node during the development of an inflammatory response, rats were inoculated with 12×10⁷ colony-forming units ofStaphylococcus aureus in the hind foot pad. Numerical changes in mast cells were then measured in the corresponding popliteal lymph node. Six days after inoculation, despite the enlargement of the responding lymph node, a marked decrease in granulated mast cell number, relative to the contralateral node, was observed in the cortical and medullary compartments. Popliteal lymph nodes from rats treated with compound 48/80 and then inoculated withS. aureus showed a higher cortical and medullary hypertrophic response and a significant increase in degranulated/weakly basophilic mast cell number in the lymph node tissue. The findings suggest that (1)Staphylococcus aureus induces a reduction in granulated mast cell number in the cortical and medullary compartments of regional lymph nodes; (2) pretreatment with compound 48/80 appears to contribute to the lymphoid cell proliferation and the hypertrophic response of lymph nodes induced byS. aureus; and (3) granulated mast cells have a regulatory role on lymphoid cell proliferation.     

IgG2 and other immunoglobulin classes on the cell surface of rat lymphoid cells

The binding to rat lymphoid cells of the F(ab′)₂ fragments of purified rabbit antibodies specific for the Fc or Fd part of rat IgG₂ was studied. Both reagents heavily labeled about 15 % and 6 % of cells from spleen and cervical lymph nodes respectively of rats kept in a conventional animal house. In contrast to this there were very few IgG₂ positive cells in the thoracic duct lymph of any animals, or in the spleen of rats from an SPF animal house. Results on the quantitative binding of rabbit antibodies against rat Fab, IgM and IgA to rat lymphoid cells are also reported. IgM positive cells in the spleen bound much more anti-IgM relative to their binding of anti-Fab antibody, than IgM positive cells from thoracic duct lymph or cervical lymph node.     

右旋糖酐-二乙烯三胺五乙酸-钆离子螯合物与马根维显在间质磁共振淋巴造影中的对比

目的 比较右旋糖酐-二乙烯三胺五乙酸 钆离子螯合物(dextran-DTPA-Gd)和马根维显两种对比剂在间质MRI淋巴造影中淋巴显影的价值。方法 选择健康成年新西兰兔12只,体重为2.7～3.7kg。仰卧位固定兔,经3D TOF CE-MRA序列扫描,平扫后右侧后肢第1、2、3趾蹼间隙注
射dextran-DTPA-Gd 各0.4ml(3.96×10^-3mol/L),共1.2ml;30min后左侧后肢第1、2、3趾蹼间隙注射马根维显各0.4ml(0.4998mol/L),共1.2ml,行MR增强扫描,扫描间隔分别为10、15、20、25、30、35、40、45、50、55、60min、2h、4h、24h。平扫和增强扫描的相关参数相同。分析不同
时间段淋巴显影强化程度,测量并计算腘窝淋巴结增强前后的信号强度(E%),绘制其信号强度-时间曲线,比较两种显影剂对淋巴显影的区别。结果 平扫时双侧腘窝淋巴结均呈等信号。右侧dextran-DTPA-Gd注射后10min,引流区后肢淋巴管及腘窝淋巴结信号强化明显、显示清晰,腘窝
淋巴结E%为212.7%,35min左右达到峰值,E%值为314.1%,4h后为208.2%,24h后扩清。左侧马根维显注射10min时,引流区域后肢血管强化明显,造影剂大部分吸收入血管进入膀胱,后肢淋巴管及腘窝淋巴结信号弱,腘窝淋巴结E%为78.8%,20min左右达到峰值,E%值为98.3%,4h后减至
29.0%,24h后扩清。淋巴结E%经统计学分析差异有统计学意义(P<0.05)。实验前后动物的生化检查等数据未见异常变化,其差异无统计学意义(P>0.05),送检的内脏器官组织学检查未见明显的病理学改变。结论 相比马根维显小分子造影剂,dextran-DTPA-Gd是一种有效的淋巴造影剂,
能够特异性靶向强化淋巴结及淋巴管。     

The barrier function of the lymph nodes in infection

Summary Fixation ofB. coli commune by the popliteal lymph nodes was studied as follows: Lymph nodes were perfused by a suspension ofB. coli commune, and studies were made of lymph taken at operation by means of fistulae in the thoracic duct and lymphatic vessels of a dog's hind limb. The ability of the lymph node to fixate bacteria is increased by immunization, particularly when the immunizing culture is injected into the area corresponding to the given node. The barrier function of the nodes increases, particularly when inflammation is provoked in them either by infectious or noninfectious agents. The nonspecific phenomena, which include intensification of the mechanical filtration and increase of phagocytic activity of the cells of the node play a significant part in the increase of lymph node barrier function in immunization.(Presented by Active Member AMN SSSR N. N. Sirotinin) Translated from Byulleten's eksperimental'noi biologii i meditsiny Vol. 49, No. 1, pp. 49–53, January, 1960     

Effect of traumatic stress on the lymph properdin level

Changes in the properdin level in different types of lymph and in the blood were studied in dogs after burns of the hind limbs (group 1) and after head injury (group 2). The properdin level in the lymph of the cervical duct and the efferent lymph flow of the popliteal lymph node were increased in dogs of both groups. The properdin level in the afferent lymph of the popliteal lymph node, thoracic duct, and blood fell after burns and rose after head injury. The total protein concentration in the afferent and efferent lymph of the popliteal lymph node and the cervical and thoracic ducts increased whereas in the blood it decreased.Course of Pathophysiology, Mordovian University, Saransk. (Presented by Academician of the Academy of Medical Sciences of the USSR P. D. Gorizontov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 85, No. 4, pp. 403–405, April, 1978.     

Difference between the lymph node response to injection of autosensitized T lymphocytes and that in a graft-versus-host reaction

Thymus (T) lymphocytes autosensitized in vitro were shown in previous studies to produce enlargement of draining popliteal lymph nodes upon injection into the footpads of syngeneic rats. Specific autoreactive effector lymphocytes were found to be recruited within these lymph nodes. In the present study, the cellular basis of lymph node enlargement in mice by autosensitized lymphocytes was compared with that produced in a graft-vs.-host (GvH) reaction. T lymphocytes of C3H mice were autosensitized against syngeneic fibroblasts in vitro for 16 to 18 h in the absence of serum, and 10⁷ lymphocytes were injected into the footpads of syngeneic mice. Control lymphocytes were incubated without fibroblasts. The GvH reaction was produced by injecting 10⁷ C3H T lymphocytes into the footpads of (C3H × C57BL)F₁ adult recipients. The index of relative enlargement of the draining popliteal lymph nodes was measured 6 days after injection. Experiments were done to identify the origin of the lymph node cells in these reactions. Irradiation of the donor lymphocytes (1000 r) or the recipient mice (550 r) was used to prevent proliferation of the lymphocytes of either origin. The participation of recipient T lymphocytes in lymph node enlargement was investigated by using thymectomized mice. The following results were obtained. 1) The GvH lymph node enlargement was found to depend on proliferation of the donor T lymphocytes, but did not seem to require the participation of radiosensitive cells within the recipient mice. 2) In contrast, the response of the lymph nodes to autosensitized donor T lymphocytes depended on the function of radiosensitive T lymphocytes within the syngeneic recipients. The autosensitized donor lymphocytes themselves did not have to proliferate to recruit the response of recipient T lymphocytes. 3) It was found that recruitment of recipient lymph node cells could be super-imposed upon a conventional GvH reaction by presensitizing the C3H donor lymphocytes in vitro. Both autosensitization against syngeneic or allosensitization against C57BL fibroblasts augmented the lymph node response of (C3H × C57BL)F₁ hybrid recipients. The recruited or donor components of these mixed responses could be selectively abolished by irradiating either the donor lymphocytes or the recipient mice. Hence, the autosensitization response, like the host-vs.-graft transplantation reaction, can be induced by sensitization of lymphocytes peripherally and involves recruitment of lymphocytes within regional lymph nodes. The GvH response manifested in the same popliteal lymph nodes does not appear to require the recruitment of radiosensitive T lymphocytes. These findings suggest that different classes of T lymphocytes function in the autosensitization and GvH responses.     

Specific antisera against recirculating and non-recirculating lymphocytes in the rat

Heterologous anti-lymphocyte sera were prepared by injecting suspensions of recirculating or non-recirculating lymphocytes into rabbits. Recirculating lymphocytes were obtained from a thoracic duct fistula, and non-recirculating lymphocytes were obtained from the blood of rats in which thoracic duct lymph had been drained away for 3 days. The cytotoxic activity of the sera was assayed by measuring the isotope release from target cells labelled with ⁵¹Cr. Antibodies specific for recirculating or non-recirculating lymphocytes could be demonstrated with the aid of cell adsorption techniques.

Cell-specific sera were used to estimate the proportion of recirculating and non-recirculating lymphocytes in lymphocyte suspensions obtained from thymus lymph nodes, blood and bone marrow. All thymocytes and most of the lymph node lymphocytes appeared to have antigenic properties in common with recirculating lymphocytes, whereas about 20% of the blood lymphocytes and most of the bone marrow lymphocytes belonged to the non-recirculating lymphocyte antigenic type.

     

Antigen localization in lymphopenic states: I. Localization pattern following chronic thoracic duct drainage

Adult rats, depleted of thoracic duct lymph for 5–7 days, were tested for their ability to localize ¹²⁵I-labelled polymerized flagellin from Salmonella adelaide. Labelled antigen was injected into both hind footpads 6–12 hours after completion of drainage, and the regional nodes were excised 24 hours later. Grain counts on identically exposed autoradiographic sections from regional nodes were used to assess differences in antigen distribution between depleted and nondepleted rats. The uptake of antigen by medullary macrophages was no different in the two groups. However, the uptake of antigen by primary lymphoid follicles was reduced by thoracic duct drainage to levels one-fourth that observed in normal rats.

Two procedures were found capable of improving follicular antigen uptake in the chronically depleted rat: (1) regional inoculations of 0.01 ml of specific antiflagellar immune serum at a titre of 1:400 1 hour prior to antigen injection, and (2) daily return by intravenous infusion of washed autogenous thoracic duct lymphocytes collected during drainage. Regional injections of both viable and non-viable lymphocytes were ineffective in improving follicular antigen uptake in the depleted animal.

The results show that depleted rats lack a serum factor, presumably an opsonin, important in determining antigen distribution patterns. It seems likely that this factor is normally manufactured by small lymphocytes.

     

The functioning in unanaesthetized sheep of the popliteal lymph node after the surgical removal of its blood supply

Operations were performed to cannulate the efferent duct of the popliteal node of sheep and, at the same time, the blood vascular system was removed surgically from the popliteal fossa so that the node was deprived of it blood supply. Twelve preparations were technically successful in that lymph flowed spontaneously from the unanaesthetised sheep for from 3 to 30 days after the operation. Eight control preparations were established in which the blood supply of the node with the cannulated efferent duct was left intact. In only four of the test preparations was the function of the node decisively impaired so that dendritic macrophages appeared in the lymph, the output of lymphocytes remained very low, and later histological examination showed the nodes to be grossly depleted of lymphocytes. In two of these four preparations the surgical devascularization of the node was aided by arterial embolization. In the remaining eight test preparations the outputs of lymphocytes in the lymph gradually regained normal values, and the nodes then responded normally to antigenic stimuli.     

The functioning in unanaesthetized sheep of the popliteal lymph node after the surgical removal of its blood supply.

Operations were performed to cannulate the efferent duct of the popliteal node of sheep and, at the same time, the blood vascular system was removed surgically from the popliteal fossa so that the node was deprived of it blood supply. Twelve preparations were technically successful in that lymph flowed spontaneously from the unanaesthetised sheep for from 3 to 30 days after the operation. Eight control preparations were established in which the blood supply of the node with the cannulated efferent duct was left intact. In only four of the test preparations was the function of the node decisively impaired so that dendritic macrophages appeared in the lymph, the output of lymphocytes remained very low, and later histological examination showed the nodes to be grossly depleted of lymphocytes. In two of these four preparations the surgical devascularization of the node was aided by arterial embolization. In the remaining eight test preparations the outputs of lymphocytes in the lymph gradually regained normal values, and the nodes then responded normally to antigenic stimuli.     

Effect of blockage of the afferent lymphatic vessels on the development of popliteal lymph nodes in the rat

The effect of blockage of the afferent lymphatic vessels on the development of popliteal lymph nodes in the rat was studied. The afferent lymphatic vessels to each popliteal node were surgically interrupted at the lowest edge of the popliteal fossa at 3, 7 or 28 days after birth and the popliteal nodes were obtained from treated animals at 4, 8 or 16 weeks after the operation. At 7 days after birth, each popliteal node was small and weighed 0.2 mg. Its parenchyma consisted of reticular cells and a small number of dispersed lymphoid elements. Four weeks after birth, each node weighed 4-5 mg, and its parenchyma comprised two layers, an outer continuous layer of peripheral cortex containing 40-50 lymph follicles and an inner discontinuous layer of deep cortex made up of 4-5 deep cortical units. At 10-12 weeks after birth, each node weighed about 10 mg and showed full structural development; the peripheral cortex contained 100-130 lymph follicles and the deep cortex consisted of 4-6 well developed units. The popliteal node was drained by 4-6 afferent lymphatic vessels, which opened into the subcapsular sinus of the node. Each lymphatic opening was topographically associated with a respective deep cortical unit, as previously described by Bélisle and Sainte-Marie (1982). In animals treated at 3 or 7 days after birth, the development of the popliteal nodes was considerably inhibited. Four weeks after surgery, each node showed 10-30 lymph follicles in the peripheral cortex and 1-3 small units in the deep cortex. Sixteen weeks after surgery, the node weighed about 4 mg and its cortex exhibited about 50 lymph follicles in the peripheral cortex and only 2 units in the deep cortex. The popliteal nodes of the treated animals generally received 2 afferent lymphatic vessels. In animals treated at 4 weeks after birth, the popliteal nodes showed no gain in weight for following 16 weeks. Four weeks after surgery, each node usually had 4-5 deep cortical units and 50-60 lymph follicles. Thereafter, some units and their overlaying peripheral cortex underwent atrophy, while others persisted. Sixteen weeks after surgery, the popliteal node showed only 2 deep cortical units and 50-60 lymph follicles, and was drained by 2 afferent lymphatic vessels. Surgical interruption of the afferent lymphatic vessels to the popliteal node at the lowest edge of the popliteal fossa did not obliterate all the draining lymphatic vessels , but reduced the number of vessels opening into the node.(ABSTRACT TRUNCATED AT 400 WORDS)     

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.     

Thoracic duct lymphocytes from nude mice: migratory properties and life-span

The thoracic duct lymphocyte (TDL) output from nude mice was 5–6 times lower than that from CBA mice during the first 24 h of drainage. Labeled TDL from nude mice (a virtually pure population of B cells) and from CBA mice (containing about 85 % T cells and 15 % B cells) were injected into nude and CBA recipients, respectively, in which thoracic duct fistulas had been established. The recovery of labeled cells in the lymph was 40 – 70 % for CBA TDL was studied and the results suggested that B cells homed predominanlty to the spleen and tended to remain there, whereas those T cells that had a much slower tempo than can T cells. The homing of ⁵¹Cr-labeled nude and CBA TDL was studied and the results suggested that B cells homed predominanlty to the spleen and tended to remain there, whereas those T cells that had initially lodged in the spleen subsequently migrated to the lymph nodes. There was a linear relationship between the appearance of labeled cells in the lymph and the period of time during which tritiated thymidine had been administered thrice daily to nude and to CBA mice. It could be calculated from the curves obtained in these mice that the potential average life-span of B cells was of the order of 8 weeks and of T cells of 16 weeks.     

胸导管的引流途径及其与周围淋巴结联系的研究

在49具胎儿尸体和5只狗,用淋巴管间接注射法,研究了胸导管的引流途径及其周围淋巴结。在胎儿,57%胸导管借胸导管侧支与周围淋巴结相连,左锁骨上淋巴结的出现率为31%。胸导管侧支、淋巴结及其输出淋巴管构成胸导管的侧副淋巴回流径路。在狗,注射后2小时,部分淋巴结显色,注射剂是经胸导管顺向流入淋巴结的。     

The influence of the lymph node on the protein concentration of efferent lymph leaving the node.

1. Experiments have been performed in sheep to determine the contribution of lymph formed within a lymph node to the total protein output in lymph leaving the node. 2. The lymphatic duct leaving the popliteal lymph node was cannulated and the protein and lymphocyte output in efferent lymph determined. The afferent lymph flow to the popliteal node was then diverted and lymph formed only within the lymph node collected from the efferent cannula. It appeared from the results that the popliteal lymph node forms lymph at the rate of approximately 1 ml. per hour and may contribute 30-50% of the protein output observed in efferent lymph. 3. The importance of lymph formation within the lymph node varied between nodes found in different regions of the body. This was due in part to the different protein concentrations in the afferent lymph to the different nodes. 4. A positive correlation was found between the protein and lymphocyte concentrations in efferent lymph from the popliteal lymph node in seven out of eleven sheep and in lymph formed within the popliteal lymph node in two out of three sheep. It is suggested that this relationship may be due to an increased transfer of plasma proteins through the post-capillary venules in the lymph node accompanying the continual traffic of lymphocytes across the wall of these vessels. The results indicated that the protein transfer across the post-capillary venules was not an indiscriminate transfer of plasma per se but a selective transport from the blood plasma compartment based on molecular size.