The differential effect of stress on natural killer T (NKT) and NK cell function

When C57Bl/6 mice were exposed to restraint stress for 12 h or 24 h, lymphocytopenia was induced in the liver, spleen, and thymus. We examined which types of lymphocytes were sensitive or resistant to such stress by a immunofluorescence test. T cells of thymic origin were sensitive while NKT and NK cells were resistant. In contrast to the increase in the proportion of NK cells, NK activity of liver lymphocytes against YAC-1 targets decreased at 24 h after stress. On the other hand, their NKT cytotoxicity against syngeneic thymocytes increased in parallel with an increase in their proportion. In perforin -/- B6 mice and B6-gld/gld (Fas ligand-) mice, NK cells were found to mediate cytotoxicity through perforin while NKT cells mediated self-reactive cytotoxicity through Fas ligand. These results suggest that stress increases the proportion of both NK and NKT cells, but that NK cytotoxicity is suppressed while self-reactive NKT cytotoxicity is not, due to a diversity of their functional mechanisms.

Dissection of differentially regulated (G+C)-rich promoters of the human parathyroid hormone (PTH)/PTH-related peptide receptor gene

The PTH/PTH-related peptide (PTHrP) receptor (PTHR) is required for normal skeletal development, and a wide array of physiological responses mediated by PTH and PTHrP. We have previously identified three promoters, P1-P3, which control human PTHR gene transcription. P2 and P3 are (G+C)-rich, function in a number of tissues, lie within the same CpG island, and display many hallmarks of housekeeping promoters. However, they are differentially regulated during development as P2, but not P3, functions in fetal tissues. Here, we have used both stably and transiently transfected human osteoblast-like cells to delineate regions of P2 and P3 required for promoter activity. Deletion analyses performed in stably transfected cells indicated that sequences extending from -91 to -12 relative to the transcription start site were required for function of the P2 promoter. No negative regulatory elements were detected in P2. In contrast, deletion of an A-rich region of P3 extending from -147 to -115 was required for optimal basal activity, suggesting that this sequence acts as a repressor of P3. Strikingly, however, whereas the A-rich region also functioned as a negative element when inserted upstream of the (G+C)-rich P2 promoter, it enhanced expression from the thymidine kinase promoter, suggesting that its function depends on other transcription factors bound to promoter sequences. Fine deletion of P3 sequences proximal to -115 implicated Spl motifs and downstream initiation sites in P3 function. These studies indicate that function of P2 and P3 is controlled by ubiquitously expressed transcription factors and raise the possibility that P3 activity is repressed during fetal development.

Organ specificity of c-kit+ lymphoid precursors in the liver, thymus, and bone marrow

c-kit+Lin- cells are present in various immune organs, including the liver, thymus, and bone marrow, where lymphoid, myeloid, or erythroid cells are generated. To compare their properties as lymphoid precursors, c-kit+Lin- cells purified from various organs of B6.Ly5.1 mice were injected into 6.5 Gy-irradiated B6.Ly5.2 mice. Depending on the source of the c-kit cells, the degree of entrance and expansion of lymphoid cells differed in the liver and thymus of recipient mice. c-kit+ cells isolated from the bone marrow entered and expanded prominently in both the liver and thymus, whereas c-kit+ cells from the thymus did not do so at all. On the other hand, c-kit+ cells isolated from the liver and spleen showed an intermediate pattern, namely, they took a long time to enter and expand in the liver and thymus of recipient mice. All of these c-kit+ cells had the potential to give rise to lymphoid cells, which were specific to the liver and thymus, respectively. We previously showed that progenitor cells for extrathymic T cells in the liver and those for conventional T cells in the thymus are not always supplied by the bone marrow, as shown by experiments using parabiosis. Taken together with those previous data, the present results suggest that c-kit+Lin- cells isolated from various immune organs have organ specific properties.

Intensive expansion of natural killer T cells in the early phase of hepatocyte regeneration after partial hepatectomy in mice and its association with sympathetic nerve activation

When C57BL/6 mice were partially hepatectomized (PHx), severe lymphocytosis was induced in the liver in the early phase of hepatocyte regeneration (4 to 12 hours after PHx). A major lymphocyte subset expanding in this organ was estimated to be natural killer 1.1(+) (NK1.1(+)) intermediate CD3 (CD3(int)) cells (i.e., NKT cells). CD3(int) cells are extrathymic T cells generated in situ in the liver. These changes were suppressed when mice with PHx were pretreated with a beta-adrenergicD antagonist (i.e., beta-blocker), propranolol (PPL). This might have been caused by sympathetic nerve stimulation during hepatocyte regeneration. An alpha-blocker showed a similar effect, although the magnitude of suppression was lower than that of the beta-blocker. We previously showed that NK and NKT cells express surface beta-adrenergic receptors and are activated in number by sympathetic nerve stimulation. In the present study, NK cytotoxicity mediated by liver lymphocytes obtained from mice with PHx decreased, whereas NKT cytotoxicity against syngeneic thymocytes increased. Purified CD3(int) cells were also found to be able to mediate NKT cytotoxicity against regenerating hepatocytes. These results suggest that sympathetic nerve stimulation after PHx results in subsequent activation of NKT cells and that these NKT cells might be associated with immunologic surveillance during hepatocyte regeneration.

Extension of the frontiers of surgical indications in the treatment of liver metastases from colorectal cancer: long-term results

OBJECTIVE

To evaluate retrospectively the long-term results of an approach consisting of performing surgery in every patient in whom radical removal of all metastatic disease was technically feasible.

SUMMARY BACKGROUND DATA

The indications for surgical resection for liver metastases from colorectal cancer remain controversial. Several clinical risk factors have been reported to influence survival.

METHODS

Between March 1980 and December 1997, 235 patients underwent hepatic resection for metastatic colorectal cancer. Survival rates and disease-free survival as a function of clinical and pathologic determinants were examined retrospectively with univariate and multivariate analyses.

RESULTS

The overall 3-, 5-, 10-, and 15-year survival rates were 51%, 38%, 26%, and 24%, respectively. The stage of the primary tumor, lymph node metastasis, and multiple nodules were significantly associated with a poor prognosis in both univariate and multivariate analyses. Disease-free survival was significantly influenced by lymph node metastasis, a short interval between treatment of the primary and metastatic tumors, and a high preoperative level of carcinoembryonic antigen. The 10-year survival rate of patients with four or more nodules (29%) was better than that of patients with two or three nodules (16%), and similar to that of patients with a solitary lesion (32%).

CONCLUSIONS

Surgical resection is useful for treating liver metastases from colorectal cancer. Although multiple metastases significantly impaired the prognosis, the life expectancy of patients with four or more nodules mandates removal.

Bone CT evaluation of nasal cavity of acromegalics--its morphological and surgical implication in comparison to non-acromegalics

PURPOSE

In order to numerically compare the morphological differences of the nasal cavity and nasal sinus between acromegalics and non-acromegalics, bone window CT scans sliced parallel to the transsphenoidal surgical route were performed. MATERIAL AND CASES: Acromegalic patients had small or large macroadenomas and were 13 (7 men and 6 women) in number, aged 53.2 +/- 16.1 years. Non-acromegalic patients had pituitary tumors and were 44 (21 men and 23 women) in number, aged 52.1 +/- 12.5 years.

RESULTS

The results of acromegalics are described in comparison to non-acromegalics in parentheses. a) The width of the surgical corridor: piriform aperture, 27.6 +/- 2.7 (25.9 +/- 2.6) mm; origin of inferior nasal concha, 29.4 +/- 9.4 (26.6 +/- 4.0) mm; and origin of middle nasal concha, 29.8 +/- 3.2 (26.2 +/- 4.2) mm. b) The depth of the surgical corridor: the upper lip thickness, 18.1 +/- 2.7 (13.3 +/- 1.4) mm; the distances between piriform aperture and sphenoid wall, 52.9 +/- 4.6 (49 +/- 4.2) mm; sphenoid wall and sellar floor, 17.3 +/- 4.1 (18.7 +/- 4.1) mm; and sellar floor to dorsum sellae, 17.6 +/- 3.4 (15.6 +/- 4.0) mm. c) Marked carotid prominence: 7/13=53.4% (8/44=18.25%). d) Sinusitis: 8/13=61.5% (12/44=27.3%).

DISCUSSION & CONCLUSION

The data presented above show that morphological differences in bony nasal cavity and soft tissue may be responsible for a deeper and narrower surgical field for acromegalics. Acromegalics had a marked carotid prominence more frequently, which needs special attention to avoid carotid injury, when enlarging the surgical field. Knowing these morphological differences will provide useful information for peri- and intra-operative care.

Maternal hypothyroidism in autoimmune thyroiditis and the prognosis of infants

We evaluated the developmental prognosis of 31 infants born to mothers with autoimmune thyroiditis. Four of the babies developed transient neonatal hypothyroidism. Their mothers all had low thyroid hormone concentrations during pregnancy. Neonatal thyroid function tended to correlate with maternal thyroid function at delivery in babies born to mothers with Graves'disease who were taking antithyroid drugs. Since severe fetal hypothyroidism sometimes results in neurological damage, it is important to maintain normal maternal thyroid function during pregnancy.

Long-term outcome of endocrine function in patients with neurohypophyseal germinomas

Since neurohypophyseal germinomas occur at the pituitary and hypothalamic axis in children and adolescents, the endocrinopathy is one of the common and critical QOL determinants. We carried out a retrospective study on the outcome of endocrine function in patients with neurohypophyseal germinoma, in order to improve or preserve pituitary function after treatment. Sixteen patients (7 men and 9 women), aged 6 to 26 years were admitted and followed up for 95.3 (14-197) months. DI was noted in 12 patients in pretreatment and 16 in posttreatment regardless of tumor size. We carried out the replacement of GH in all 8 patients, presenting the symptoms under 15 years of age. Gonadal or gonadotropic, thyroid and adrenal hormones were replaced in 9, 12 and 15 patients, respectively. Patients with large tumor compressing chiasm or hypothalamus needed hormonal replacement such as gonadal or gonadotropic and thyroid hormones more frequently (<0.01) than those with small one. In addition, two patients with a small tumor at the pituitary stalk and the 3rd ventricle floor showed the improvement of secretion pattern in gonadotropins and ACTH after chemotherapy, although they later needed radiation therapy to control the tumor. Based on our study and review of literature, the endocrinological studies before and after treatment demonstrated that pituitary dysfunction present before treatment persisted or worsened even after tumor remission, except for patients with small and localized ones. The poor endocrine results is considered to be largely radiation-related. Chemotherapy alone seems to be insufficient to obtain complete response (CR). To avoid radiation related pituitary injury, combination of 24 Gy or less dosage of radiation and appropriate chemotherapy is essential. The earlier diagnosis by repeatedly using neuroimaging and serum and CSF tumor markers and earlier initiation of treatment, before irreversible pituitary-hypothalamic damage occurs, contributes to improvement of the outcome of pituitary functions in patients with neurohypophyseal germinomas.

Methylation patterns of human parathyroid hormone (PTH)/PTH-related peptide receptor gene promoters are established several weeks prior to onset of their function

Expression of the human parathyroid hormone (PTH)/PTH-related peptide receptor (PTHR) gene is controlled by three promoters, P1-P3. P1 functions specifically in kidney, whereas P2 is ubiquitously active. P3 is also widely active, although more so in kidney than other tissues. However, only P2 functions at midgestation. We examined the role of methylation in controlling PTHR promoter activity. Function of all promoters was inhibited by CpG methylation in vitro. Significantly, P1 is selectively hypomethylated in adult kidney in vivo, strongly suggesting that demethylation is required for renal P1 function. Moreover, this pattern is established by 11. 75 weeks of fetal age, several weeks prior to the onset P1 activity. P3 is unmethylated at midgestation, although it is inactive at this stage of development, and thus exhibits characteristics of both tissue-specific and ubiquitously active promoters. These results show that adult methylation patterns of P1 and P3 are established several weeks prior to their induction, indicating that their function requires factors expressed late in development.

Accurate preoperative evaluation of liver mass lesions without fine-needle biopsy

Fine-needle biopsy (FNB) is associated with problems, such as tumor seeding, which are probably underestimated. The aim of this study was to validate prospectively the accuracy of our diagnostic work-up without FNB, for defining indications for surgery in a cohort of patients with focal liver lesions (FLLs). Between January 1997 and December 1998, 160 consecutive patients carrying 225 FLLs admitted to our department were evaluated prospectively. Preoperative diagnoses were established by means of clinical histories, serum tumor marker levels, ultrasonography, and spiral computed tomography (CT). Angiography, magnetic resonance imaging (MRI), and Lipiodol-CT were performed when it was considered necessary to plan the surgical strategy. All the patients underwent surgery and results of pathological examinations were obtained for all of them. The preoperative diagnoses of 221 of the 225 lesions (98.2%) were confirmed, and the indications for liver resection in 156 of the 160 patients (97.5%) were correct. The respective accuracy, sensitivity, specificity, and positive and negative predictive values were 99.6%, 100%, 98.9%, 99.3%, and 100% for diagnosis of hepatocellular carcinoma (HCC); 99.1%, 100%, 98.8%, 96.9%, and 100% for metastases; 99.6%, 100%, 99.5%, 91%, and 100% for cholangiocellular carcinomas (CCCs); all 100% for mixed HCC-CCCs; and 98.7%, 57.1%, 100%, 100%, and 98.6% for benign tumors. In view of these results, the fact that the real risks of FNB have yet to be established and the possibility that tumor seeding has a major impact on patient prognosis, the use of FNB should be drastically limited.

The majority of lymphocytes in the bone marrow, thymus and extrathymic T cells in the liver are generated in situ from their own preexisting precursors

Parabiotic pairs of B6.Ly5.1 and B6.Ly5.2 mice were used to investigate how lymphocytes in various organs and various lymphocyte subsets mixed with partner cells. The origin of partner cells was determined by using anti-Ly5.1 mAb in conjunction with immunofluorescence tests. Parabiosis was also produced after the irradiation of B6.Ly5.2 mice at various doses to prepare an immunosuppressive partner. Irrespective of irradiation, lymphocytes and other hematopoietic cells in the bone marrow and lymphocytes in the thymus showed a low mixture of partner cells in comparison with those of all other organs tested. On the other hand, lymphocytes in the blood, spleen, and lymph nodes became a half-and-half mixture of their own cells and partner cells by 14 days after parabiosis. Among lymphocyte subsets, intermediate CD3 cells (i.e., CD3int cells) and NKT cells (i.e., NK1.1+ subset of CD3int cells) in the liver also showed a low mixture of partner cells. The present results raise the possibility that lymphocytes in the bone marrow and thymus, and extrathymic T cells in the liver might be in situ generated from their own preexisting precursor cells. Another observation was that, after irradiation, partner cells showed accelerated mixture even if they showed a low mixture under non-irradiated conditions. However, only lymphocyte subsets with the same phenotype as those of preexisting cells entered the corresponding sites.

Quick recovery in the generation of self-reactive CD4low natural killer (NK) T cells by an alternative intrathymic pathway when restored from acute thymic atrophy

The thymus comprises the mainstream of T cell differentiation which produces conventional T cells and an alternative pathway which produces primordial T cells with intermediate density of T cell receptor (TCR)-CD3 complex on the surface (i.e. intermediate TCR cells or TCRint cells). We induced acute thymic atrophy in mice by an administration of hydrocortisone (10 mg) or irradiation (6.5 Gy). It was demonstrated that CD3intCD4lowNK1.1+ T cells were immediately generated by an alternative intrathymic pathway without passing through the double-positive CD4+8+ stage, when restored from thymic atrophy (days 3-14). These CD3intCD4lowNK1.1+ T cells mediated self-reactivity and appeared even in the periphery. mRNA of an invariant chain of TCR Valpha14Jalpha281 gene product was detected in these CD4low T cells, but not remaining CD4high T cells. The mainstream of T cell differentiation in the thymus was not restored up to day 14 and there was no leakage of self-reactive clones into the population generated through the mainstream. These results reveal that an alternative intrathymic pathway is associated with the generation of self-reactive T cells, in an early restoration phase after thymic atrophy.

Mechanisms underlying immunologic states during pregnancy: possible association of the sympathetic nervous system

NK and extrathymic T cells are abundant in the decidua of the pregnant uterus. To determine how this unique pattern is induced, overall populations of leukocytes were examined in the blood and other tissues in pregnant women. Time-kinetic studies showed that a basal change of leukocytes during pregnancy was granulocytosis and lymphocytopenia in the blood. This change might be due to sympathetic nerve activation during pregnancy, because the administration of catecholamine is known to activate myelopoiesis in the bone marrow. In addition to the numerical change, the functional activation of NK and extrathymic T cells also seemed to be present. This might be due to NK cells and extrathymic T cells (as well as granulocytes), which carry a high density of surface adrenergic receptors. Such functional activation of NK and extrathymic T cells was more prominent in the blood and urine in patients with preeclampsia and hyperemesis gravidarum than in normal pregnant women. The present results suggest that the activation of granulocytes, NK cells, and extrathymic T cells is essential for the maintenance of pregnancy but that overactivation thereof may be responsible for the onset of pregnancy disorders.

Outcome of a baby born from a mother with acquired juvenile hypothyroidism having undetectable thyroid hormone concentrations

We report a baby born from a mother with strongly positive thyroid stimulation blocking antibody (TSBAB) and nearly undetectable T4 level. This case is a unique model of nearly complete absence of thyroid hormones during fetal and early neonatal life in humans. The infant girl was born by cesarean section, because of fetal bradycardia, after 41 weeks gestation and received mechanical ventilation for 3 days. The TSH level was more than 120 microU/mL in the neonatal thyroid screening. At age 17 days, the results of a thyroid function study showed undetectable free T3 and free T4 concentrations, TSH 550 microU/mL, and TSH receptor antibody (TRAB) 87%. Thyroxine at a dose of 30 microg/day was started at age 17 days. The patient required thyroxine treatment until age 8 months. The brain magnetic resonance image at age 2 months revealed reduced brain size. Her auditory brain stem response was absent at age 2 months. The audiogram at age 4 yr revealed sensorineural deafness of 70 dB. When she was 6 yr of age, motor development remained the same as that at age 4 months. Her height was 106 cm (- 1.5 SD). The results of thyroid function study of the mother 23 days after delivery showed undetectable free T3 and free T4, TRAB 84%, and TSBAB 83%. In conclusion, the outcome of severe thyroid hormone deficiency in utero and early in human neonatal life was normal physical growth, fetal distress resulting in cesarean section, difficulty in the onset of breathing, permanent deficit in auditory function, brain atrophy, and severely impaired neuromotor development despite the start of an adequate dose of thyroxine replacement during the neonatal period.

Cytotoxic pathways in the skin allograft rejection by CD4+ T cells

BACKGROUND

Two major mechanisms of T cell-mediated cytotoxicity are known: perforin-dependent and Fas-dependent cytotoxic pathways. Previous studies in vitro demonstrated that CD4+ cytotoxic T lymphocytes use the Fas pathway as a primary cytotoxic mechanism, but the cytotoxic mechanisms used by CD4+ T cells in vivo are unclear.

METHODS

We examined the cytotoxic pathways of CD4+ T cells in vivo using a skin allograft model, in which athymic nu/nu mice were transplanted with skin allografts and reconstituted with purified CD4+T cells. Fas-deficient and perforin-deficient mice and anti-tumor necrosis factor (TNF)-alpha monoclonal antibody were used for inactivating each cytotoxic pathway in vivo.

RESULTS

The skin allografts from Fas-deficient mice were readily rejected by the athymic mice reconstituted with purified CD4+ T cells. Perforin-deficient CD4+ T cells could also reject Fas-deficient skin allografts. Furthermore, in vivo treatment with anti-TNF-alpha monoclonal antibody did not prevent the allograft rejection by CD4+ T cells in the absence of both Fas and perforin pathways.

CONCLUSIONS

These results indicate participation of undefined mechanisms other than Fas, perforin, and TNF-alpha pathways in CD4+ T cell-mediated cytotoxicity in vivo.

Neurodegeneration in hereditary nucleotide repair disorders

Both xeroderma pigmentosum group A (XPA) and Cockayne syndrome (CS) are rare autosomal disorders, have a genetic defect in the step of nucleotide repair, and involve various neurological abnormalities caused by progressive neurodegeneration. We performed comprehensive neuropathological analysis of five cases of XPA and four cases of CS. The XPA cases showed widespread neuronal loss throughout the central nervous system, in sharp contrast to the comparative preservation of neurons in the CS cases, who rather exhibited patchy demyelination in the cerebral and cerebellar white matter, and multifocal calcium deposition in the basal ganglia and cerebral white matter, respectively. Exceptionally in the cerebellar cortex, neuronal loss was more severe in CS than in XPA. Grumose or foamy spheroid bodies occurred in the globus pallidus and substantia nigra, and axonal torpedoes were increased in the cerebellar cortex in both disorders. Neither silver impregnation nor immunohistochemistry for ubiquitin or tau succeeded in visualizing neurofibrillary tangles, senile plaques or augmented ubiquitination in either disorder, and these findings did not support the involvement of facilitated aging in the neurodegeneration in XPA or CS.

Administration of glucocorticoids markedly increases the numbers of granulocytes and extrathymic T cells in the bone marrow

Glucocorticoids, steroid hormones, are widely used as an anti-inflammatory drug. However, clinicians have sometimes encountered adverse drug reactions such as ulcers and tissue damage. In this study, we investigated how such adverse reactions of glucocorticoids are evoked, using an experimental mice model. When hydrocortisone (0.5 or 1.0 mg/day/mouse) was administered daily for 2 weeks, severe leukocytopenia was induced in all immune system organs. However, granulocytes (Gr-1(+)Mac-1(+)) were increased in number in the bone marrow and peripheral blood. This seemed to be due to an elevated level of myelopoiesis in the bone marrow. As well as increasing in number, granulocytes were functionally activated as estimated by the Ca2+ influx and superoxide production. The proportion of primordial T cells (CD3(int)IL-2Rbeta+) in the thymus and the number of primordial T cells in the bone marrow also increased. Mice administered hydrocortisone became susceptible to stress. Thus, these mice showed gastric ulcers when they were exposed to restraint stress for 12 h. These results suggest that activated granulocytes and primordial T cells might provide a mechanism involved in steroid ulcers and tissue damage, possibly through the superoxide production of granulocytes and the autoreactivity of primordial T cells.

Pringle's maneuver lasting 322 min

Up to now, the reported limit of 'continuous' Pringle's maneuver during hepatectomy has not exceeded 127 min. Here we used 'intermittent' clamping to increase the cumulative time of safe ischemia. A 49 year-old man who had undergone jejunal resection because of leiomyosarcoma was referred with 18 hepatic metastases. Using 'intermittent' Pringle's maneuver, enucleation of the entire tumor was performed. The cumulative ischemic time of the liver was 322 min, but post-operative serum level total bilirubin remained normal. The patient was discharged on day 24 without any complications, remaining well for up to 5 months after surgery. The present case shows that the safe upper limit of cumulative hepatic ischemia can be extended to 322 min.

Rupture of hepatocellular carcinoma after transcatheter arterial embolization: an unusual case

Rupture of hepatocellular carcinoma (HCC) as a complication of transcatheter arterial embolization (TAE) is very rare. An unusual rupture of HCC after TAE was treated with successful surgical resection. A 65 year-old woman with liver cirrhosis developed multiple HCC in both lobes of the liver. TAE was attempted for the HCCs, but the original left hepatic artery, obliterated due to the previous repeated TAEs, was replaced by the left gastric artery. Right hepatic arteries were embolized while preserving the replaced left hepatic artery. Nine days after TAE, the patient presented a rupture of HCC in the left lateral segment of the liver, in which no deposit of Lipiodol was recognized. Since additional TAE to achieve hemostasis failed, left lateral segmentectomy was carried out with concern for the poor hepatic functional reserve. The patient was discharged 3 weeks after surgery without any complication. This is the first case of ruptured HCC in the non-embolized part of the liver after TAE, which was resected successfully.

Autosomal dominant familial hypoparathyroidism and sensorineural deafness without renal dysplasia

OBJECTIVE

A family is described which has a unique combination of autosomal dominant hypoparathyroidism and sensorineural deafness without renal dysplasia.

CASE REPORT

The proband was a male infant aged 1 month with episodes of seizures for 20 days. He was born at 35 weeks' gestation without asphyxia, weighing 2040 g. His initial calcium, phosphorus and percentage of tubular reabsorption of phosphorus were 6.8 mg/dl (normal range 8.5-10.5 mg/dl), 8.9 mg/dl (normal range 5.5-7.4 mg/dl) and 96.8% (normal range 85-95%) respectively. He had normal values for serum parathyroid hormone (PTH) and 25-hydroxyvitamin D. No abnormalities were found by renal imaging and a routine renal function study. He showed a brisk plasma cAMP increase in response to human PTH-(1-34) infusion. He had normal karyotype 46, XY, without a microdeletion in chromosome 22q11.2 by an in situ hybridization method. Five family members were affected with hypoparathyroidism with sensorineural deafness with autosomal dominant transmission. The study of calcium-sensing receptor and preproPTH gene showed a normal DNA sequence.

CONCLUSION

The combination of familial hypoparathyroidism with sensorineural deafness without renal dysplasia is novel and the cause may be distinct from previously reported familial hypoparathyroidism with sensorineural deafness and renal dysplasia.

Difference in height associated with a translation start site polymorphism in the vitamin D receptor gene

The function of 1,25-dihydroxyvitamin D3 in bone development is to regulate the differentiation or proliferation of osteoblastic, osteoclastic, and chondrocytic lineage, affecting bone mineralization and linear bone growth. An A(T/C)G substitution exists in the first of the two putative translation initiation sites in exon 2 of the vitamin D receptor (VDR) gene. We studied the relationship between exon 2 polymorphism and height in 90 healthy Japanese female subjects aged 18-20 y, who had attained final height, in 159 healthy Japanese aged 13 y, and 24 children with constitutional short stature aged 6-10 y less than -1.5 SD in height, mostly with parents of normal height. Exon 2 polymorphism was analyzed by PCR-single strand conformation polymorphism, PCR-direct sequencing, and PCR-restriction fragment length polymorphism. The frequency of the exon 2 polymorphism was genotype CC (ACG/ACG), 0.37; genotype CT (ACG/ATG), 0.51; and genotype TT (ATG/ATG), 0.12 in 249 normal subjects. The mean height of female subjects aged 18-20 y with the genotype CT was 160.3 +/- 4.3 cm (mean +/- SD), whereas that with CC was 4.4 cm lower (p < 0.0001), and that with TT was 2.7 cm lower (p = 0.0302). At age 13 y, this trend was observed, and the mean height SD score of subjects with the genotype CT was taller than homozygotes (CC/CT; p = 0.0363 and CT/TT; p = 0.0208) in 159 subjects. Genotype CT in 24 children with constitutional short stature was less frequent than other genotypes (CC, 0.62; CT, 0.21; TT. 0.17) (chi 2 p value, 0.0171). In conclusion, the exon 2 polymorphism affecting the VDR mRNA and protein is one of the major determinants of adult height at least in female Japanese, which was noted at the age of 13 y examined in both sexes.

Low level of mixing of partner cells seen in extrathymic T cells in the liver and intestine of parabiotic mice: its biological implication

c-kit+ stem cells have recently been found in the liver and intestine of adult mice. We examined whether such stem cells give rise to extrathymic T cells in these organs in situ. To this end, we used parabiotic B6.Ly5.1 and B6.Ly5.2 mice, i.e. mice sharing the circulation. The origin of lymphocytes was identified by anti-Ly5.1 and anti-Ly5.2 monoclonal antibodies in conjunction with immunofluorescence assays. Lymphocytes in the blood, spleen, lymph nodes and liver had become a half-and-half mixture of Ly5.1+ and Ly5.2+ cells in both individuals by day 14. However, this level of mixing decreased in extrathymic T cells in the liver (i.e. NK T cells) and intestine by day 14 and thereafter. The same was observed in T cells of the thymus. The data from immunohistochemical staining supported the results of immunofluorescence assays for suspension cells. The present results raise the possibility that extrathymic T cells in the liver and intestine may arise from their own pre-existing precursor cells, possibly from their own stem cells. Another important finding was that the composition pattern of lymphocyte subsets in one individual was quite similar to that in its partner at various sites. This result was interpreted to mean that only selected partner cells migrate to specific sites in the other partner individual.

Serous cystadenoma of the pancreas with invasive growth: benign or malignant?

We describe a case of serous cystadenoma, that invaded a lymph node and adipose tissue. Preoperatively, the cystic lesion of the pancreas was diagnosed as a serous cystadenoma and subsequently the patient, a 71-yr-old woman, underwent distal pancreatectomy with splenectomy. Macroscopically, a greyish white, externally lobulated and partly ovoid tumor, measuring 12 x 8.5 x 5 cm, occupied the pancreatic body and tail extensively. In cross-section, multiple nodules were observed, which measured from 0.5 to 3 cm in diameter, were separated by hyalinized fibrous septa and were filled with numerous microcysts. Light microscopic findings were consistent with those for serous cystadenoma. At the splenic hilus, the tumor was found to have invaded the lymph node and adipose tissue. Based on the clinicopathological features of the six reported cases, including the present case (which behaved in a malignant fashion in terms of pathological findings of invasion or metastasis), serous cystadenoma should be regarded as having the potential for malignant growth.

Developmental upregulation of human parathyroid hormone (PTH)/PTH-related peptide receptor gene expression from conserved and human-specific promoters

The parathyroid hormone (PTH)/PTH-related peptide (PTHrP) receptor (PTHR) functions in skeletal development and mediates an array of other physiological responses modulated by PTH and PTHrP. PTHR gene transcription in mouse is controlled by two promoters: P1, which is highly and selectively active in kidney; and P2, which functions in a variety of tissues. P1 and P2 are conserved in human tissue; however, P1 activity in kidney is weak. We have now identified a third human promoter, P3, which is widely expressed and accounts for approximately 80% of renal PTHR transcripts in the adult. No P3 activity was detected in mouse kidney, indicating that renal PTHR gene expression is controlled by different signals in human and mouse. During development, only P2 is active at midgestation in many human tissues, including calvaria and long bone. This strongly suggests that factors regulating well conserved P2 control PTHR gene expression during skeletal development. Our results indicate that human PTHR gene transcription is upregulated late in development with the induction of both P1 and P3 promoter activities. In addition, P2-specific transcripts are differentially spliced in a number of human cell lines and adult tissues, but not in fetal tissues, giving rise to a shorter and less structured 5' UTR. Thus, our studies show that both human PTHR gene transcription and mRNA splicing are developmentally regulated. Moreover, our data indicate that renal and nonrenal PTHR gene expression are tightly coordinated in humans.

Participation of NK1.1+ T cells in the rejection of lpr alphabetaT cells when bone marrow cells of lpr mice are transplanted into B6 mice

When C57BL/6 (B6) mice were irradiated (9 Gy) and received bone marrow (BM) cells of B6-lpr/lpr mouse origin (i.e., lpr-->B6), all mice died within 6 days. In the irradiated B6 mice, radioresistant CD3 IL-2Rbeta+ NK cells and IL-2Rbeta+ CD3int cells (i.e., CD3int cells of extrathymic origin) remained, especially in the liver. There were two subsets, NK1.1+ and NK1.1-, among the IL-2Rbeta+ CD3int cells. However, the NK1.1+ subset (i.e., NK1.1- T cells) was much more radioresistant, and the majority of CD3int cells belonged to this subset in irradiated mice. The expansion of lymphocytes from injected BM cells did not occur in the irradiated B6 mice. However, such expansion did take place in irradiated B6-lpr/lpr mice injected with both BM cells of B6-lpr/lpr and B6 origin. As a result, the mice subjected to BM cells survived. Irradiated B6 mice were treated in vivo with anti-NK1.1 mAb or anti-asialoGM1 antibody to eliminate NK cells alone or both NK cells and NK1.1+ T cells. When irradiated B6 mice were pretreated with anti-NK1.1 mAb, the mice could survive. These results suggest that intact NK1.1+ T cells of extrathymic origin may recognize abnormal BM cells with the lpr gene and inhibit the expansion of lymphocytes, including abnormal double-negative CD4 8 cells, in B6-lpr/lpr mice. To inhibit the expansion of lymphocytes, mechanisms other than Fas ligand/Fas molecules on extrathymic T cells may be responsible.