Thoracic Duct Drainage Research Articles

Thoracic duct drainage patterns in heterotaxy

BackgroundDisordered lymphatic drainage is common in congenital heart diseases (CHD), but thoracic duct (TD) drainage patterns in heterotaxy have not been described in detail. This study sought to describe terminal TD sidedness in heterotaxy and its associations with other anatomic variables. MethodsThis was a retrospective, single-center study of patients with heterotaxy who underwent cardiovascular magnetic resonance imaging at a single center between July 1, 2019 and May 15, 2023. Patients with (1) asplenia (right isomerism), (2) polysplenia (left isomerism) and (3) pulmonary/abdominal situs inversus (PASI) plus CHD were included. Terminal TD sidedness was described as left-sided, right-sided, or bilateral. ResultsOf 115 eligible patients, the terminal TD was visualized in 56 (49 %). The terminal TD was left-sided in 25 patients, right-sided in 29, and bilateral in two. On univariate analysis, terminal TD sidedness was associated with atrial situs (p = 0.006), abdominal situs (p = 0.042), type of heterotaxy (p = 0.036), the presence of pulmonary obstruction (p = 0.041), superior vena cava sidedness (p = 0.005), and arch sidedness (p < 0.001). On multivariable analysis, only superior vena cava and aortic arch sidedness were independently associated with terminal TD sidedness. ConclusionsTerminal TD sidedness is highly variable in patients with heterotaxy. Superior vena cava and arch sidedness are independently associated with terminal TD sidedness. Type of heterotaxy was not independently associated with terminal TD sidedness. This data improves the understanding of anatomic variation in patients with heterotaxy and may be useful for planning for lymphatic interventions.

Anesthetic challenges in patients with multicompartmental lymphatic failure after Fontan palliation undergoing transcatheter thoracic duct decompression.

Lymphatic flow abnormalities are central to the development of protein losing enteropathy, plastic bronchitis, ascites and pleural effusions in patients palliated to the Fontan circulation. These complications can occur in isolation or multicompartmental (two or more). The treatment of multicompartmental lymphatic failure aims at improving thoracic duct drainage. Re-routing the innominate vein to the pulmonary venous atrium decompresses the thoracic duct, as atrial pressure is lower than systemic venous pressure in Fontan circulation. Transcatheter thoracic duct decompression is a new minimally invasive procedure that involves placing covered stents from the innominate vein to the atrium. Patients undergoing this procedure require multiple general anesthetics, presenting challenges in managing the sequelae of disordered lymphatic flow superimposed on Fontan physiology. We reviewed the first 20 patients at the Center for Lymphatic Imaging and Intervention at a tertiary care children's hospital presenting for transcatheter thoracic duct decompression between March 2018 and February 2023. The patients ranged in age from 3 to 26 years. The majority had failed prior catheter-based lymphatic intervention, including selective embolization of abnormal lympho-intestinal and lympho-bronchial connections to treat lymphatic failure in a single compartment. Fourteen had failure in three lymphatic compartments. Patients were functionally impaired (ASA 3-5) with significant comorbidities. Concurrent with thoracic duct decompression, three patients required fenestration closure for the resultant decrease in oxygen saturation. Ten patients had improvement in symptoms, seven had no changes and three have limited follow up. Five (25%) of these patients were deceased as of January 2024 due to non-lymphatic complications from Fontan failure.

CMR 3-115 - Thoracic Duct Drainage Patterns in Patients with Abnormalities of Thoraco-abdominal Situs

CMR 3-115 - Thoracic Duct Drainage Patterns in Patients with Abnormalities of Thoraco-abdominal Situs

THERAPEUTIC THORACIC DUCT DRAINAGE: A SYSTEMATIC REVIEW OF THE EASTERN EUROPEAN EXPERIENCE AND FUTURE POTENTIAL

Thoracic duct drainage (TDD) is gaining renewed interest, largely due to accumulation of evidence supporting the gut-lymph model, where toxic mesenteric lymph from the intestine contributes to development of multi-organ failure in acute and critical illness (ACI). Advances in minimally invasive TDD have added to this growing interest. The English TDD literature has been previously reviewed, but the more extensive Eastern European literature has not been available to English readers. Therefore, we undertook a systematic search of Eastern European human TDD studies using Scopus and PubMed databases and Russian language websites. Indications for TDD, clinical outcomes, and complications were reviewed. 113 studies, published between 1965 and 2015, were reviewed. The most common indications for TDD were hepatic failure, acute pancreatitis, and peritonitis. It was often used late and when other treatment options had been exhausted. Human TDD appeared safe and probably effective, especially when combined with lymphosorption. The benefit appeared to correlate with the volume of lymph drained. A randomized controlled trial (and some case-control studies) showed reduced mortality in patients with ACI with TDD. Other benefits included rapid normalization of blood parameters and decreased organ edema. This review provides further support for the gut-lymph model and justification for high quality randomized controlled trials of TDD in ACI. It also highlights other potential indications for TDD, such as bridging patients with liver failure to surgery or transplant.

The prenatal intervention progress of primary fetal hydrothorax

Primary fetal hydrothorax(PFHT) is an uncommon congenital disease.Fetal hydrothorax is thought to be due to leakage of lymphatic fluid in the pleural space either caused by direct leakage of lymphatic fluid from the thoracic duct, overproduction or impaired drainage of lymph.The outcome of fetal hydrothorax may vary from spon-taneous resolution without postnatal morbidity to severe fetal hydrops and perinatal death.At present, there is no consensus on the treatment of PFHT.Now, the latest researches progress on prenatal ultrasonographic characteristics, prenatal diagnostic procedures, prenatal intervention, and prognosis in PFHT, were reviewed combined with the diagnosis and treatment principle of single center in Guangdong Women and Children′s Hospital, which would provide useful guidance for clinical treatment of PFHT. Key words: Fetus; Primary fetal hydrothorax; Prenatal diagnosis; Prenatal intervention

Antivenom effect on lymphatic absorption and pharmacokinetics of coral snake venom using a large animal model

Context: Historically, administration and dosing of antivenom (AV) have been guided primarily by physician judgment because of incomplete understanding of the envenomation process. As demonstrated previously, lymphatic absorption plays a major role in the availability and pharmacokinetics (PK) of coral snake venom injected subcutaneously, which suggests that absorption from subcutaneous tissue is the limiting step for venom bioavailability, supporting the notion that the bite site is an ongoing venom depot. This feature may underlie the recurrence phenomena reported in viperid envenomation that appear to result from a mismatch between venom and AV PK. The role of lymphatic absorption in neutralization of venom by AV administered intravenously remains unclear.Methods: The effect of AV on systemic bioavailability and neutralization of Micrurus fulvius venom was assessed using a central lymph-cannulated sheep model. Venom was administered by subcutaneous injection in eight sheep, four with and four without thoracic duct cannulation and drainage. Two hours after venom injection, AV was administered intravenously. Venom and AV concentrations in serum and lymph were determined by ELISA assay from samples collected over a 6-h period and in tissues harvested post-mortem.Results: After AV injection, venom levels in serum fell immediately to undetectable with a subsequent increase in concentration attributable to non-toxic venom proteins. In lymph, AV became detectable 6 min after treatment; venom levels dropped concurrently but remained detectable 4 h later. Post-mortem samples from the venom injection site confirmed the presence of venom near the point of injection. Neither venom nor AV was detected at significant concentrations in major organs or contralateral skin.Conclusions: Intravenous AV immediately neutralizes venom in the bloodstream and can extravasate to neutralize venom absorbed by lymph but this neutralization seems to be slow and incomplete. Residual venom in the inoculation site demonstrates that this site functions as a depot where it is not neutralized by AV, which allows the venom to remain active with slow delivery to the bloodstream for ongoing systemic distribution.

Lymphatic Circulation Disseminates Bartonella Infection Into Bloodstream.

The hallmark of Bartonella infection is long-lasting intraerythrocytic parasitism. However, the process of Bartonella bacteremia is still enigmatic. In the current study, we used Bartonella tribocorum to determine how Bartonella invasion into the bloodstream from dermal inoculation might occur. Bartonella was poorly phagocytized by peritoneal macrophages in vitro. Intracellular Bartonella survived and replicated in macrophages at an early stage of infection. Intracellular Bartonella inhibited spontaneous cell death of macrophages. They also inhibited Salmonella-induced pyroptosis and mildly reduced inflammasome activation through an unidentified mechanism. A rat model confirmed that Bartonella was also inadequately phagocytized in vivo, because numerous free-floating bacilli were observed in lymph collected from thoracic duct drainage as early as 2 hours after inoculation. Lymphatic fluid drainage in the bloodstream significantly reduced the bacterial load in the bloodstream. These findings illustrated a potential route by which Bartonella invade bloodstream from dermal inoculation before they are competent to infect erythrocytes.

Physiology and pathophysiology of the lymphatic system. Research results and further prospects

The review summarizes own research and literature on the role of the lymphatic system in a number of physiological and pathological conditions. The typical reaction of lymph circulation seen in shock, acute diffuse peritonitis, in postoperative period is the lymph flow volumetric rate increase. Mobilization of the lymphatic system, extravascular fluid and proteins in well-studied emergencies is explained considering the role of the lymphatic system as a natural source of circulating blood volume regulation and serum proteins replacement («autotransfusion»). These pathological processes are associated with progression of lymphatic failure on the late terms. The principle of lymph circulation targeted stimulation as a way to detoxify the body using hormones and procaine (Novocain) blockade of splanchnic nerves and the borderline sympathetic trunks was proposed based on modeled acute peritonitis. Increased microcirculation and central lymph flow, alterations in resorption, transport and filtration barrier function of the lymphatic system, as well as morphologic and functional reorganization of the lymph nodes were revealed in fever of different duration. Of particular interest are studies on the role of the lymphatic system in the immediate and long-term body adaptation to physical stress. Activation of central lymph circulation in adequate dynamic loads correlated with changes in the system lymph microcirculation (acceleration of lymph flow, increased peristalsis of the lymph microvessels walls and contractile activity of their valves). Extreme physical exhaustion was accompanied by expressed lymphovascular, extravascular and intravascular changes in the microvasculature. Lymphatic failure, as well as structural microcirculation impairments in a trained body occur only in extreme physical stress. Thus, the lymphatic system is involved in many physiological and pathological processes; its functional condition affects the course and outcome of the disease. Therefore, the treatment of the diseases requires, among other measures, correction of lymph formation and circulation (stimulation or inhibition, endolymphatic treatment, thoracic duct drainage, lymphosorption, blockade of nodal pathways and other methods - depending on the specific disease).

Blocking abdominal lymphatic flow attenuates acute hemorrhagic necrotizing pancreatitis -associated lung injury in rats

BackgroundAcute hemorrhagic necrotizing pancreatitis (AHNP) is a severe acute inflammatory of pancreas that can lead to extrapancreatic organ disfunction. The lung and intestine is the most common involved organs, and abdominal lymphatic flow may contribute to AHNP- associated organ injury. In this study, we investigated the impact of thoracic duct ligation and drainage on lung and intestine injury in rats with AHNP.MethodsThirty-two male Wistar rats were randomly divided into 4 groups: sham operation group, AHNP group, AHNP + ligation group and AHNP + drainage group. Rat AHNP model was induced by retrograde injection of 3.5% sodium deoxycholate into the biliopancreatic duct, and the sham operation group was injected only with saline. In AHNP + ligation group and AHNP + drainage group, thoracic duct was ligated or drainaged before model induction. At 6 h after model induction, the bronchoalveolar lavage fluid (BALF) were collected for determination of tumor necrosis factor-alpha (TNF-alpha), and the tissues of lung, intestine and pancrease were harvested individually for pathohistological evaluation and the myeloperoxidase (MPO) activity determination. In addition, the activity of serum amylase and diamine oxidase (DAO) was determined in each group.ResultsThe pathohistological damage and MPO of lung, intestine and pancrease, TNF-alpha of BALF, serum amylase and DAO were all increased in AHNP group compared to those in sham operation group (P < 0.05). In AHNP + ligation group, the pathohistological damage and MPO of lung and TNF-alpha of BALF were reduced, but the pathohistological damage and MPO of intestine and pancrease were increased compared with AHNP group (P < 0.05), however the activity of serum amylase and DAO was no changed. In AHNP + drainage group, the pathohistological damage and MPO of lung, intestine and pancrease, TNF-alpha of BALF, serum amylase and DAO were all reduced compared to those in AHNP group (P < 0.05).ConclusionsOur finding suggest that thoracic duct ligation can reduce neutrophil infiltration and TNF-alpha release and then attenuates lung injury in rats with AHNP, but aggravates the injury of intestine and pancrease. While thoracic duct drainage attenuates the injury of lung, intestine and pancreaseat the same time in rats with AHNP.

Effectiveness of the Treatment with Thoracic Duct Drainage for the Rheumatoid Arthritis

Effectiveness of the Treatment with Thoracic Duct Drainage for the Rheumatoid Arthritis

Long Term Results of the Treatment of Thoracic Duct Drainage for the Rheumatoid Arthritis

Long Term Results of the Treatment of Thoracic Duct Drainage for the Rheumatoid Arthritis

Forty Years of Publication of Transplantation Proceedings—The Second Decade: The Cyclosporine Revolution

With surgical tools in place, increased knowledge concerning immunogenetics and alloimmunity as well as improved management of immunocompromised patients, the foundations were lain for the rapid development of the transplantation enterprise. In contrast to pre-transplant conditioning by thoracic duct drainage or total lymphoid irradiation, which were too cumbersome for routine execution among the burgeoning recipient pool, cyclosporine was a facile method to produce immunosuppression de novo after transplantation. On the one hand, clinical data confirmed the potency of cyclosporine in a variety of clinical settings. On the other hand, a pleiotropic array of side effects, particularly nephrotoxicity, beclouded the regimens, even when used in reduced doses in combination with azathioprine or together with rigorous individualization of therapy by concentration control. The advent of cyclosporine condemned conditioning by pretransplant blood transfusions and donor-recipient HLA matching to therapeutic obsolescence. However, cross-matching achieved greater significance particularly due to the development of flow cytometry methods to detect modest amounts of anti-donor antibody. Adjunctive treatments with polyclonal preparations or monoclonal antibodies were developed to provide an additional layer of security during the critical induction phase of immunosuppression and for treatment of rejection episodes refractory to high dose steroid therapy. Active immunologic investigation was stimulated by antibodies that discriminated CD4+ versus CD8+ T cells, leading to dissection of their numbers of precursors or mature elements as well as their distinct activities. The search for methods to induce, maintain and detect the state of transplantation tolerance continued. The encouraging results in clinical transplantation raised a variety of ethical concerns related to public attitudes; to retrieval, distribution, and allocation of the limited supply of deceased donor organs; the increased utilization of living persons; the opportunities for commerce; the quasi-righteous requests for organ gifts by unrelated individuals and the scant financial resources for long-term treatment with costly immunosuppression. Transplantation had now achieved its rightful place in the clinical armamentarium.

Computed Tomographic Lymphography of the Thoracic Duct by Mesenteric Lymph Node Injection

To document a novel technique to image the thoracic duct and its tributaries by contrast enhanced computed tomography (CT) lymphography. Clinical report. Dogs (n=6) idiopathic chylothorax. Ultrasonography was used to guide percutaneous injection of intestinal lymph nodes with nonionic iodinated contrast medium for preoperative CT lymphography of the thoracic duct in 6 dogs with chylothorax. Thoracic CT images were acquired immediately after contrast medium injection. All dogs had subtotal pericardectomy and thoracic duct ligation. Postoperative thoracic duct lymphography was performed in 3 dogs. Superficial cervical lymph node lymphography was performed in 2 dogs to determine cervical lymphatic contribution to thoracic effusions. Preoperative thoracic duct lymphography using this technique was successful in delineating the cisterna chyli, thoracic duct, and associated lymphatic vessels in all dogs. Immediate postoperative lymphography performed in 2 dogs revealed successful duct ligation in 1 dog and persistent lymphatic leakage in the other. A 1-month postoperative thoracic duct lymphogram performed in 1 dog revealed unsuccessful ligation or recannulation of 1 of 3 redundant vessels seen preoperatively. Percutaneous CT lymphography results in excellent detection of the thoracic duct and abnormal thoracic duct drainage patterns both pre- and postoperatively. The contribution of superficial cervical lymph node drainage to reoccurrence of effusions can be evaluated. Percutaneous CT lymphography using ultrasound-guided contrast medium injection should be considered as an alternative to conventional open abdominal approaches to radiographic or CT lymphography.

Exploring the feasibility of selective depletion of T lymphocyte subsets by whole blood immunoadsorption cytapheresis

Normal turnover of T lymphocytes is slow relative to other blood cells. Consequently, the physical removal of circulating leucocytes by thoracic duct drainage, repeated leukapheresis or blood filtration results in T cell depletion and immunosuppression. However, clinical use of such procedures is impractical compared with immunosuppressive drugs or radiation. None the less, immunosuppression by physical depletion of T cells, avoiding the systemic toxicities of drugs and radiation, might have clinical advantages if immunophenotypically distinct T cell subsets could be depleted selectively. Recent advances in targeted plasma protein apheresis using adsorbent macrobead columns prompted us to determine whether analogous techniques might permit CD4+ T lymphocytes to be removed selectively from whole blood. To explore this possibility, we linked murine anti-human-CD4 and isotype-identical control monoclonal antibodies (mAbs) to agarose, polyacrylamide and polystyrene macrobeads (150-350 microm) and then evaluated the selectivity, specificity and efficiency of macrobead columns to remove CD4+ T cells from anti-coagulated whole blood at varying mAb densities and flow rates. We also examined saturation kinetics and Fc-oriention versus random coupling of mAbs to macrobeads. Sepharose 6MB macrobead (250-350 microm) columns proved to be most effective, selectively removing up to 98% of CD4+ T cells from whole blood. Moreover, depletion efficiency and selectivity were retained when these columns were reused after elution of adherent CD4+ cells. These studies indicate that selective depletion of T lymphocyte subsets by whole blood immunoadsorption apheresis using mAb-linked macrobead columns may be feasible on a clinical scale. It is possible that such apheresis techniques could achieve targeted forms of immunosuppression not possible with drugs or radiation.

Anomalies of thoracic lymph duct drainage demonstrated by lymphoscintigraphy and review of the literature about these anomalies

Aims To determine the frequency of supradiaphragmatic lymph nodes that receive lymph from the lower limbs and the intraabdominal organs. Methods Three hundred and thirty-four bipedal lymphoscintigraphy results of the lower limbs were reviewed. Results Lymph nodes were visualized in only the supraclavicular/retroclavicular (SRC) area in 113 cases (33.2%, 109 on the left and 4 on the right), in only the mediastinum in 5 cases (1.5%), in the mediastinum and the left SRC area in 18 cases (5.5%), in the mediastinum and right SRC area in 2 cases (0.6%), in the mediastinum and both SRC areas in 6 cases (1.8%), and in the mediastinum and as 1 chain draining in the left axilla in 2 cases (0.6%). Conclusions Supradiaphragmatic lymph nodes associated with the thoracic duct and receiving lymph and/or chyle from the infradiaphragmatic body were demonstrated in 43.2% of our patients and in 11.1% of the cases these lymph nodes were not located in the left retroclavicular area. These data should be taken in mind by surgeons when confronting an intrathoracic and even extrathoracic supradiaphragmatic chylous effusion after surgeries which imply lymph nodes and/or lymphatic vessels.

Detection of Chylothorax and Cervical Cystic Hygroma in Hydrops Fetalis Using Lymphoscintigraphy

A 2-month-old boy was diagnosed as having nonimmune hydrops fetalis. Lymphoscintigraphy of the lower extremities revealed accumulation of radiotracer in the middle mediastinum on both sides indicating leakage of lymphatic flow from the thoracic duct at 1 hour. There was visualization of radiotracer in both lung fields suggestive of chylothorax. Radioactivity was noted accumulating in the neck consistent with the areas of cystic hygromas on the 4-hour image. Visualization of the cystic hygromas was believed to be the result of feeding of the lymphatic flow from the tributaries of the right lymphatic trunk and thoracic duct or aberrant lymphatic drainage pathways.

The effect of experimental haemorrhagic shock on the bacterial content of thoracic duct lymph.

The effect of haemorrhagic shock on the simultaneous appearance of enteric micro-organisms in the central lymph and the portal blood was studied in 30 dogs. Irreversible haemorrhagic shock results in portal bacteraemia but the lymph remains sterile. Thoracic duct drainage is harmful and hastens the onset of irreversibility.

Immunosuppression in liver transplantation

Early mythology depicts two saints in a life-anddeath struggle to save a limb from a foregone fate. Saints Cosmos and Damien replaced a cancerous leg with a limb from a deceased Moor. This illustration was mere fantasy until the latter part of the previous century with the seminal surgeries performed by Dr. Joseph Murray on identical twins and, later, Dr. Starzl’s pioneering orthotopic liver transplant (OLT). Immunosuppression itself has come from the dark ages to where it stands today: a careful balancing act between toxicity and rejection. 1-3 This article is designed as an overview of current immunosuppression in OLT and will not delve into areas such as basic science or pipeline preview. The first attempts at whole liver grafting were carried out in 1955 with auxiliary grafts. This involved insertion of an extra liver at an ectopic location. This approach left the diseased liver intact. Early results, however, were disappointing. This early experience in the animal model and later attempts in humans led to the development of the OLT model. This was first attempted in 1963 in humans and today is the primary model for liver transplantation. 4 Early immunosuppression was suboptimal at best. Corticosteroids and azathioprine were used in combination by Starzl et al. in his first 5 transplants. The majority of the Colorado series from 1963 to 1976 received corticosteroids, azathioprine, and antilymphocyte globulin. A total of 170 patients were transplanted, and approximately 50% were children. Patients were divided into 3 time-based series. Series 1 (1963-1976, 111 patients) had a 1-year survival rate of 28.8%, Series 2 (1976-1978, 30 patients) had a 1-year survival rate of 50%, and the Series 3 (1978-1979, 29 patients) had a 1-year survival rate of 34.5%. Variations on these approaches included thoracic duct drainage or cyclophosphamide, though neither produced significant advantage. The Cambridge University group reported on a series from 1968 to 1980 with a total of 93 patients, with a 1-year survival rate of 23.7%. The lower survival rate may have been due to the lower rate of pediatric patients transplanted by the Cambridge group. 5,6 This time frame has been referred to as the precyclosporine (CyA) era (Fig. 1).

Immunosuppressive Effect of Long-Term Drainage of Thoracic Duct on Immunological Memory in Adult Thymectomized Rats

Profound reduction of the recirculating lymphocyte pool using thoracic duct drainage (TDD), a method developed by Gowans et al, has been shown to be of limited immunosuppressive value when applied in experimental as well as in clinical settings across major histocompatibility antigen complex (MHC) differences. This limitation is due to the observation that animals, in particular mice, are normally not able to have the drainage last longer than 8 to 10 days. However, using a simple modification of TDD, we have established a long-term TDD method, ie, more than 20 days. Combining this long-term TDD with adult thymectomy, we have examined the life span of naïve and memory T cells specific for the minor histocompatibility antigen H-Y in female lewis rats. Furthermore, we demonstrated that memory T cells specific for the H-Y antigen do not appear to be recirculating lymphocytes.

LIFE SPAN OF NAÏVE AND MEMORY T CELLS IN ADULT THYMETOMIZED RTAS

P978 Aims: Life span of naïve and memory T cells in general is controversial. Inasmuch as immunological function of naive and memory T cell in adult thymecomized rats following a long-term thoracic duct drainage (TDD), has not been examined, we studied the life span of naïve and minor histocompatibility antigen H-Y-sensitized female LEW rats with respect to immunological T cell. Methods: Adult thymectomy was applied to female LEW rats. Anti-H-Y immunity in female LEW rats was established by immunization of female LEW rats by male LEW bone marrow cell (BMC) derived-DC. Employing a long-term thoracic duct drainage (TDD), i.e., more than 20 days, which heretofore has not been able to do so, and skin grafting were applied to examine whether and to what extent T cell mediated-immunity of naive and/or memory –induced female LEW rats to minor histocompatibility antigen H-Y was influenced. Results: Six months after adult thymectomy, naïve LEW female rats were found to reject to H-Y incompatible male isografts. Moreover, a long-term TDD method, i.e., more than 20 days or longer, combined with adult thymectomy was found to be so critical that the drained rats were not able to reject strong MHC-incompatible skin allograft. Furthermore, when it applied to minor H-Y-sensitized female LEW rats, it was demonstrated that the cells from the long term TDD-rats contained class II positive, thymus independent T cell-lineage cells (more than 80 %) which heretofore have not been described. Functional analysis of the male specific antigen H-Y sensitized LEW rats showed that 20 days-TDD female LEW rats were not able to reject male isografts. However, three to four weeks resting after the drainage, the resting female LEW rats were found to reject male isografts. Conclusions: Our studies demonstrated that life span of naïve T cells to minor histocompatibility antigen H-Y was relatively long, i.e., more than six months. Impairment of immunological T cell memory following a long-term TDD was associated with appearance of class II positive T cells and the transient dysfunction of T cell memory was functionally recovered by three to four weeks resting from a long term-TDD. To our knowledge this is the first report demonstrating the evidence for presence of long-lived naïve T cells to minor histocompatiblity antigen H-Y. Functional and transient impairment of immunological T cell memory associated with a long-term TDD was not due to the loss of memory T cell in TDL.