Effectiveness of combined plasma cell therapy and costimulation blockade based desensitization regimen in heart transplant candidates

BACKGROUND

Desensitization is one of the strategies to reduce antibodies and facilitate heart transplantation in highly sensitized patients. We describe our center's desensitization experience with combination of plasma cell (PC) depletion therapy (with proteasome inhibitor or daratumumab) and costimulation blockade (with belatacept).

METHODS

We reviewed five highly sensitized patients who underwent desensitization therapy with plasma cell depletion and costimulation blockade. We evaluated the response to therapy by measuring the changes in cPRA, average MFI, and number of positive beads > 5000MFI.

RESULTS

Five patients, mean age of 56 (37-66) years with average cPRA of 98% at 5000 MFI underwent desensitization therapy. After desensitization, mean cPRA decreased from 98% to 70% (p = .09), average number of beads > 5000 MFI decreased from 59 to 37 (p = .15), and average MFI of beads > 5000 MFI decreased from 16713 to 13074 (p = .26).

CONCLUSION

Combined PC depletion and CoB could be a reasonable strategy for sustained reduction in antibodies in highly sensitized patients being listed for heart transplantation.

The Zonal Architecture of the Mandibular Condyle Requires ADAMTS5

Temporomandibular joint (TMJ) osteoarthritis (TMJOA) disrupts extracellular matrix (ECM) homeostasis, leading to cartilage degradation. Upregulated a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS)-5 leads to cleavage of its substrate aggrecan (Acan) and is considered a hallmark of TMJOA. However, most research on ADAMTS5-Acan turnover has focused on hyaline cartilage, not fibrocartilage, which comprises the TMJ. The mandibular condylar cartilage (MCC) of the TMJ is organized in zones, and chondrocytes are arranged in axial rows, yet the molecular mechanisms required to generate the MCC zonal architecture have not been elucidated. Here, we test the hypothesis that ADAMTS5 is required for development of the TMJ MCC. Adamts5^+/+ and Adamts5^-/- murine TMJs were harvested at postnatal day 7 (P7), P21, 2 mo, and 6 mo of age; histomorphometrics indicated increased ECM. Immunohistochemistry and Western blots demonstrated the expanded ECM correlated with increased Acan localization in Adamts5^-/- compared to Adamts5^+/+. Cell volume was also decreased in the MCC of Adamts5^-/- due to both a reduction in cell size and less mature hypertrophic chondrocytes. Analysis of chondrogenic maturation markers by quantitative real-time polymerase chain reaction indicated Col2a1, Col10a1, and Sox9 were significantly reduced in Adamts5^-/- MCC compared to that of Adamts5^+/+. The older (6 mo) Adamts5^-/- MCC exhibited changes in chondrogenic cell arrangements, including clustering and chondrogenic atrophy, that correlated with early stages of TMJOA using modified Mankin scoring. These data indicate a potentially novel and critical role of ADAMTS5 for maturation of hypertrophic chondrocytes and establishment of the zonal architecture that, when disrupted, may lead to early onset of TMJOA.

THE NUMBER OF ACETYLCHOLINESTERASE MOLECULES IN THE RAT MEGAKARYOCYTE

A megakaryocyte cell series from rat bone marrow has been examined by the isotopic di-isopropyl fluorophosphate (DFP) method for esterases. After complete reaction with 32P-DFP, the numbers of DFP-reacted molecules in individual cells have been determined by β track auto-radiography. Previous work has shown the percentage of organophosphate-sensitive sites in these cells which can be taken as active centers of acetylcholinesterase (AChase). Combining these data, the absolute numbers of organophosphate-sensitive esterase molecules and AChase molecules per cell were determined. Histograms show a narrow spread of values within each of four size classes from megakaryoblast to fully mature megakaryocyte, but, with means increasing 4-fold through this series, approximately in proportion to cell volume. A rat megakaryoblast has 2 x 106 AChase molecules, and a megakaryocyte (of 48-µ diameter) has 7.6 x 106 molecules. The apparent turnover number of the enzyme for intracellular reaction with substrate is calculated and compared with turnover numbers available for other AChases.

Review of pharmacology and physiology in thrombolysis interventions

Reperfusion therapy using thrombolytic agents has been shown to be a safe and effective treatment strategy for arterial ischemia, venous thrombosis, massive pulmonary embolism, and acute stroke. Thrombolytic agents have evolved over the course of a few decades, from nonfibrin selective to fibrin-selective agents. The development and modification of these agents have resulted in improved understanding of their pharmacologic attributes, and their effects on the complex molecular events that occur during thrombolysis goal-directed therapies. The current review focuses on the physiology and pharmacology of the thrombolytic agents that have been or are currently in use for interventional thrombolysis interventions. Attention is also given to the particular role that thrombolytic agents play in the current management of peripheral vascular disease and acute stroke.

Effect of culture in vitro and organ culture on the dry mass of preimplantation mouse embryos

The dry mass of mouse embryos cultured in vitro in medium alone or in an organ culture system were measured by means of the Vickers M86 scanning microinterferometer. The data were compared with previous data on the dry mass of preimplantation embryos in vivo. The metabolism of embryos cultured in vitro differs from that of fresh embryos. In cultured embryos, dry mass decreases throughout the 2-cell stage whereas the dry mass is increasing at this stage in vivo. Embryos in an organ culture system regain a dry mass profile, similar to that observed in vivo at the late cleavage stage. These results support the view that conditions for embryo metabolism are suboptimal in vitro and that, although the oviduct may confer some advantage on developing embryos in vitro, it is unable fully to support the pattern of metabolism, as assessed by dry mass, observed in vivo.

Variation in the dry mass of mouse embryos throughout the preimplantation period

Information on the net balance of embryonic metabolism during the preimplantation period is provided by measurements of embryo dry mass. The dry mass of mouse embryos at 10 defined stages of preimplantation development was measured using the Vickers M86 scanning microinterferometer. The results demonstrate that there is an overall loss of dry mass from the unfertilized ovum (39.10 +/- 0.6 ng) to the late blastocyst stage (32.80 +/- 0.53 ng) with these differences being highly significant. However, there is a significant increase in embryonic dry mass from the 1-cell (36.88 +/- 0.34 ng) to 2-cell stage (40.48 +/- 0.40 ng). These results suggest that protein synthesis exceeds degradation during the 2-cell stage but that from the 4-cell to morula stage the reverse is true. In addition, the variation in dry mass between embryos at the same developmental stage is extremely small, suggesting that this may be a useful indicator of embryonic viability.

Rural hospitals: still on the critical list

"Survive 'til '95." This rural hospital battle cry may prove to be prophetic. The next five years will determine how health care is delivered in the United States. Time is critical for rural hospitals, and their responses to changes ahead will determine their future.

A morphometric study of the human endometrial stroma during the peri-implantation period

In this study we have examined the human endometrial stromal cell population in well-timed biopsies during the peri-implantation period, using traditional stereological techniques. This paper reports data obtained from 16 women of known fertility who underwent endometrial biopsies at known times after the luteinizing hormone (LH) surge (four each at LH + 2, LH + 4, LH + 6 and LH + 8). The average stromal cell nuclear diameter increased in size throughout the period of study (P less than 0.01), with a significant decrease (P less than 0.05) in the nuclear profile axial ratio. This suggests that the nuclei were increasing in size and becoming more rounded. There was a dramatic increase (P less than 0.01) in the rounded. There was a dramatic increase (P less than 0.01) in the packing density between LH + 2 and LH + 6; this is likely to be due, at least in part, to the glands filling up with secretory products and so compressing the intervening stroma. A substantial decrease (P less than 0.01) was seen in the packing density between LH + 6 and LH + 8. This corresponds to the time when stromal oedema is thought to be maximal.

A quantitative study of endometrial development in the luteal phase: comparison between women with unexplained infertility and normal fertility

This study compared endometrial development in the luteal phase of women with unexplained infertility (n = 30) with that in women with normal fertility (n = 70) by the use of quantitative histological techniques (morphometric analysis) on endometrial specimens which were precisely timed from the luteinizing hormone surge. When overall endometrial development (histological dating) was considered, the proportion of women with unexplained infertility who had retarded endometrial development (20%) was found to be significantly higher than for women with normal fertility (3%) (P less than 0.01). When individual histological features were considered, women with unexplained infertility were found to have significant deviation from the normal range established from fertile women in only five of the 14 histological features measured. All of these five features related to the glandular but not to the stromal component of the endometrium; four of these five features are related to glandular secretory activity.

An endometrial factor in unexplained infertility

OBJECTIVE

To study a group of women with unexplained infertility to see whether they have a defect that is intrinsic to the endometrium.

DESIGN

Evaluation of the functional response of the endometrium by examining endometrial biopsy specimens using immunohistochemical methods in a group of women with unexplained infertility and in a control group of women with normal fertility.

PATIENTS

27 Women with unexplained infertility (average age 33.2); median duration of infertility five years. A control group of 44 women with normal fertility (average age 33.8) who were requesting sterilisation or reversal of sterilisation.

SETTING

Infertility clinic, Jessop Hospital for Women, Sheffield.

INTERVENTION

Secretory phase endometrial biopsy specimens were taken, with informed consent, as an outpatient procedure.

MAIN OUTCOME MEASURES

Immunohistochemistry with monoclonal antibody D9B1, was used to assess the production and secretion of an oligosaccharide epitope produced by endometrial gland cells between two and seven days after the luteinising hormone surge. A reflected light measuring system was used to assess the amount of epitope within the gland cells, and in the gland lumen.

RESULTS

In the control group of women, mean reflected light measurements at the cell base and cell apex peaked at three and five days after the luteinising hormone surge respectively, and in the gland lumen the epitope accumulated rapidly from three days, reaching a peak at seven days. In the women with infertility the peaks of epitope at the cell base and cell apex were lower, broader, and delayed in onset, and the build up of epitope in the gland lumen was retarded. The synthesis and secretion of the epitope in the women with infertility was therefore significantly reduced and delayed, even in the presence of normal concentrations of circulating progesterone.

CONCLUSIONS

The results suggest that a primary dysfunction of the endometrium might be associated with hitherto unexplained infertility.

A morphometric study of the human endometrial stroma during the peri-implantation period

In this study we have examined the human endometrial stromal cell population in well-timed biopsies during the peri-implantation period, using traditional stereological techniques. This paper reports data obtained from 16 women of known fertility who underwent endometrial biopsies at known times after the luteinizing hormone (LH) surge (four each at LH + 2, LH + 4, LH + 6 and LH + 8). The average stromal cell nuclear diameter increased in size throughout the period of study (P less than 0.01), with a significant decrease (P less than 0.05) in the nuclear profile axial ratio. This suggests that the nuclei were increasing in size and becoming more rounded. There was a dramatic increase (P less than 0.01) in the packing density between LH + 2 and LH + 6; this is likely to be due, at least in part, to the glands filling up with secretory products and so compressing the intervening stroma. A substantial decrease (P less than 0.01) was seen in the packing density between LH + 6 and LH + 8. This corresponds to the time when stromal oedema is thought to be maximal.

The effects of steroids on the fine structure of the endometrium

This brief review illustrates the lack of ultrastructural studies on human endometrium, particularly on well-dated material from normal, fertile women. The glandular epithelium, with its triad of unusual organelles in the early luteal phase, poses fascinating problems in cell biology and, probably for this reason, has attracted the most work. Many problems in reproductive biology, in uterine pathology and in the study of unexplained infertility are crying out for detailed study of the luminal epithelium, the stroma and the blood vessels. If this review, by highlighting the gaps in our knowledge, stimulates research into these areas, it will have been successful.

How precise is histologic dating of endometrium using the standard dating criteria?

Sixty-three endometrial biopsies were dated histologically by using the standard criteria on two separate occasions by the same observer. Overall, it was found that exact agreement occurred in 15 (24%), but disagreement of more than 2 days occurred in 6 (10%). The proportion of exact agreement in the first half of the luteal phase (32%) was found to be significantly higher (P less than 0.05) than that in the second half of the luteal phase (9%). In a separate part of the study, 27 women had two endometrial biopsies, each performed in a separate cycle. The within-subject between-cycle variation of the results of endometrial dating (exact agreement: 4%, disagreement of more than 2 days: 41%) was found to be significantly different from intraobserver variation (P less than 0.01 for both). The amount of intraobserver variation suggests that the traditional dating criteria are not precise enough to quantify corpus luteum function in the second half of the luteal phase, whereas the amount of within-subject between-cycle variation implies that the result of endometrial dating in one cycle cannot be used reliably to predict that of another cycle.

The endometrial cycle: the expression of a secretory component correlated with the luteinizing hormone peak

This paper reports the pattern of production and secretion of a secretory phase epitope in the endometrium of 44 normal fertile women. Peroxidase immunochemistry was used to detect the monoclonal antibody D9B1, which binds to a peptide-associated sialylated oligosaccharide, in endometrial biopsies all chronologically dated from the luteinizing hormone (LH) peak. During the proliferative phase, the epitope was shown to be absent from tissue sections. It first made its appearance within gland cells 2 days after the LH peak. By LH+3 a rapid accumulation of the D9B1 epitope was noted in the base of the cell, below the nucleus. On subsequent days, increasing amounts of the antigen were detected in the apical cytoplasm, apparently in a more concentrated form than in the basal cell zone. On day LH+6, around the time of implantation, secretory vesicles in the cell apex were discharged into the gland lumen where the glycoconjugate finally accumulated. This immunohistochemical approach introduces a new parameter for evaluation of endometrial function and could be used to improve the accuracy of histological assessment of the endometrial cycle.

The relation between daily salivary progesterone profile and endometrial development in the luteal phase of fertile and infertile women

This study analysed the relation between daily salivary progesterone profiles in the luteal phase and endometrial development as assessed by morphometric studies of endometrial biopsies that were timed by luteinizing hormone surge. Among 34 fertile women studied, a threshold relation was noted between cumulative salivary progesterone concentration and 11 of the 17 morphometric features measured, as well as the results of the histological dating. Above the observed threshold, a significant linear correlation was found between cumulative salivary progesterone and the results of histological dating. Among 55 women, progesterone profile in the first half of the luteal phase, but not the second half, was found to be significantly lower in those with retarded endometrial development than in those with normal development. Overall, 50% of retarded endometrial development was associated with a subnormal progesterone profile, but the other 50% was associated with a normal progesterone profile, in keeping with an abnormal response of the endometrium due to progesterone receptor deficiency. Retarded endometrial development was more likely to be associated with a subnormal progesterone profile in the first half of the luteal phase than in the second half.

The effects of progesterone receptor blockade in the luteal phase of normal fertile women

The effects of a single, variable dose (5 to 200 mg) of RU38486 (RU486) (Roussel-Uclaf, Paris, France) in the first half of the luteal phase of the menstrual cycle were studied in 30 normal fertile volunteers. Quantitative histologic techniques were employed, and the results were compared with normal ranges derived from a separate, normal, fertile population. It was found that RU486 inhibited glandular secretory activity, accelerated degenerative changes, induced various vascular changes, increased stromal but not glandular mitotic activity, and did not affect the predecidual reaction. The superiority of morphometric analysis over traditional dating criteria was demonstrated in this study of endometrial responses to an exogenously administered agent. In addition, it was found that temperature drop occurred in 56%, menstrual induction in 43%, luteolysis in 24%, mood change in 23%, and thirst sensation in 3% of women studied. Both menstrual induction and changes in hypothalamic function after the administration of RU486 occurred independently of luteolysis and so were likely to be the direct result of progesterone receptor blockade in these organs. Menstrual induction was significantly related to the dose given and the day on which RU486 was administered. Mood change was significantly related to the day on which RU486 was given. Most of the effects of RU486 occurred around 48 hours after its administration.

Why does RU486 fail to prevent implantation despite success in inducing menstruation?

The administration of RU38486 (RU486) in the luteal phase may induce menstruation, but it may not be associated with shedding of the functional layer of the endometrium. This provides an explanation why, in some cases of successful menstrual induction by RU486, pregnancy continues undisturbed. The ability of RU486 to interrupt a very early pregnancy is more likely to be related to its ability to cause shedding of the endometrium than its ability to induce menstruation.

The ultrastructure of the glandular epithelium in the timed endometrial biopsy

This paper reports the electron microscopic appearance of the uterine glandular epithelium in a group of 25 women of known fertility who underwent endometrial biopsies at known times after the luteinizing hormone (LH) surge between LH + 2 and LH + 6. The use of these well-timed endometrial biopsies enables one to gain a clearer insight into the cellular dynamics of the glandular cells, between ovulation and the middle of the luteal phase. Under the influence of progesterone, the cells are transformed from relatively inactive cells full of free ribosomes to very active polarized cells, containing giant mitochondrial profiles, intracellular deposits of glycogen/glycoprotein-rich material and a complex intranuclear channel system. Intimate associations between organelles develop, the most notable being that between a semi-rough endoplasmic reticulum and the mitochondria. By taking biopsies that are accurately timed, relative to the LH surge, from a group of women of known fertility, the sequences of changes in ultrastructure are established with considerably more precision than was previously available.

An examination of the variation in timed endometrial biopsies

Endometrial biopsies were obtained from fertile women, aged 20-40 years, with regular cycles of 25-35 days. Chronological dating of the material was carried out by determination of the luteinizing hormone (LH) peak by daily LH assay. Tissue was taken from three or four sites along the biopsy and processed for electron microscopy. Half micron thick sections were analysed by light microscopy and a morphometric examination of the glandular epithelium carried out. Nuclear size was assessed using an unbiased measuring technique and the volume density of the nucleus in the cell was also measured. A series of 12 women was examined, four at each of days LH + 2, 4 and 5. An attempt was made to control a variety of factors which contribute to the variability in the histological dating of the endometrial biopsy. In doing so it was possible to analyse the relative contributions of each sampling level to the overall variance. In contrast to earlier studies there is a relatively small intersubject variation with a correspondingly large within-biopsy variation. These results may indicate that the cellular events in the glandular epithelium, between ovulation and the middle of the luteal phase, are precisely regulated.

A new method of histologic dating of human endometrium in the luteal phase

Morphometric analysis was performed on 70 endometrial biopsy specimens collected from a population of fertile women. Of the 17 morphometric measurements that were performed on each endometrial biopsy, only 5 were required to achieve a highly significant correlation with chronologic dating based on luteinizing hormone surge (R = 0.99). The result of histologic dating, based on morphometric analysis of endometrial biopsies collected from a separate, unbiased population, correlated strongly and significantly with chronologic dating (r = 0.98, P less than 0.0001). The correlation was better than that achieved when histologic dating was performed according to the conventional dating criteria (r = 0.88, P less than 0.001).

The relative sensitivities of autoradiographic emulsions to negative chemography

Nuclear emulsions from Ilford, Kodak (U.K.), Eastman Kodak and Sakura have been exposed under comparable conditions to sections known to cause negative chemography. Kodak AR-10 and Eastman Kodak NTB-2 and NTB-3 emulsions did not show negative chemography. Ilford K5, K2 and L4 and Sakura NR-M2 showed varying degrees of chemography. The results suggest a correlation between mean crystal diameter and susceptibility to this artefact.

Survival of the fittest?

Rural hospitals in Texas struggle to survive, but some just don't. In the past four years, 49 Texas hospitals have closed. Why? While there are many reasons, the bottom line is financial problems.

A comparison between two methods of chronological dating of human endometrial biopsies during the luteal phase, and their correlation with histologic dating

This prospective study was performed on 61 infertile women to examine the correlation between histologic dating using the same criteria by two independent observers and chronological dating by two different methods: (1) determination of luteinizing hormone (LH) peak by daily LH assay, (2) calculation based on the onset of the next menstrual period (NMP). The correlation between histologic dating and chronological dating was found to be significantly better if the LH peak was used to determine the chronological date than if the NMP was used (r = 0.70 and 0.37, respectively).

Prevention of negative chemography in phenylenediamine stained autoradiographs of plastic semithin sections

Negative chemography is the loss of latent image during autoradiographic exposure, due to reactive groups in the specimen. Tissue fixed with glutaraldehyde and osmium tetroxide, block stained with p-phenylenediamine and embedded in Epon for light microscope sections causes intense negative chemography when autoradiographed by dipping in Ilford K2 emulsion: this cannot be completely prevented by separating section from emulsion by means of a layer of evaporated carbon. Chemical treatment of the sections before autoradiography may reduce the chemography. Treatment with 1% hydrogen peroxide for 15 min reduced it to such an extent that subsequent coating with 5 nm carbon abolished it. Material block stained in this way gave excellent contrast, both for light and electron microscopy.

Cell organization in the stroma of the rat uterus. II. Responses to progesterone in the ovariectomised rat

The organisation and activity of cells in the uterine stroma of ovariectomised rats have been studied over the 24 hours following an injection of progesterone. Autoradiographically, the rate of incorporation of [3H]lysine falls 1 hour after progesterone, rising progressively at 3 and 7 hours to levels higher than in control animals. A gradient of grain density is evident at 1, 3 and 7 hours, higher in regions adjacent to luminal epithelium than near the muscularis. No such gradient appears relative to glandular epithelium. Morphometric studies show that the array of stromal cells 24 hours after progesterone is similar to that in control rats, except that cells near the luminal epithelium are larger in the former group. At intermediate times, changes in cell size and spacing occur throughout the stroma in patterns that vary with distance from luminal epithelium. The organisation and activity of cells in the uterine stroma change in response to progesterone in a manner conditioned by their position in the uterus, in particular by their distance from luminal epithelium.

Cell organization in the stroma of the rat uterus. I. The ovariectomised rat

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Changes in the fine structure of the apical plasma membrane of endometrial epithelial cells during implantation in the rat

In previous work we have shown that ovarian hormones, when injected into ovariectomized rats, alter the fine structure of the plasma membrane of endometrial epithelial cells. In this paper freeze-fractures have been used to study the apical plasma membrane of endometrial epithelial cells of rats during the period of blastocyst implantation of normal pregnancy. On day 1 of pregnancy there were 2354 +/− 114 intramembranous particles (IMPs) per micrometer2 of membrane. The particles were spherical and randomly distributed. On day 5 of pregnancy IMP density rose to 2899 +/− 289 per micrometer2 and some rod-shaped particles were also visible. By day 6 of pregnancy IMP density had risen to 4014 +/− 206 per micrometer2 and there were more rod-shaped IMPs than before. In addition, on day 6 IMPs were also present as rows of particles and some gap-junction-like arrays of particles were also seen. Our findings indicate that there are fine-structural alterations in the apical plasma membrane of endometrial epithelial cells, the site of first contact between maternal and embryonic cells, during the period of early pregnancy. The findings are discussed in the light of suggested mechanisms of blastocyst attachment to the uterine epithelium at implantation.

The structure of tight junctions between uterine luminal epithelial cells at different stages of pregnancy in the rat

The ultrastructure of tight junctions between uterine luminal epithelial cells of the pregnant rat was studied by the freeze-fracture technique. On day 5 of pregnancy, the day of implantation, the region of tight junctions extended three times as far down the lateral cell membrane as on day 1 of pregnancy, and the strands of the complex interlinked more frequently. These observations suggest that tight junctions on day 5 may be more efficient in preserving the contents of the uterine lumen from dilution or escape than at earlier times of pregnancy.

Loss of microvilli caused by glycerol treatment of uterine epithelial cells

We have used freeze-fracture electron microscopy to examine the effects of glycerol treatment of unfixed cells of a compact tissue – the uterine luminal epithelial cell. These cells respond in a similar fashion to other cells, i.e., the intramembranous particles (IMPs) become clustered. In addition we show that glycerol reduces the number of microvilli on these cells and we discuss two mechanisms that may contribute to both clustering of IMPs and loss of microvilli.

Reflexive gap junctions on uterine luminal epithelial cells

Freeze-fracture electron microscopy has been used to search for reflexive gap junctions on apical projections of uterine epithelial cells in the rat. These structures were found in 5 of 6 animals in the study and consisted of from 15 to over 70 intramembranous particles which ranged in size from 7 to 9 nm. Some suggestions on the function of these enigmatic junctions are discussed.

Recovery of bronchial epithelium on stopping smoking

Bronchial biopsy specimens were studied from 19 patients, comprising five non-smokers, eight current smokers, and six people who had given up smoking between two and 16 years previously. By using a recently developed morphometric technique the structural state of the bronchial epithelium was assessed and described by a score, which specifies the extent to which the epithelial histology departs from the normal, through the changes of mucous-cell hyperplasia and squamous-cell metaplasia. The epithelium was nearer normal in former smokers than current smokers in each of six pairs matched for smoking history. The numerical scale permitted statistical analysis with a precision that is not possible with data based on subjective diagnosis alone: the results of comparing histology with pack-years of cigarette consumption were consistent with the hypothesis that structural recovery occurs in bronchial epithelium in people who stop smoking for over two years.

Effects of ovarian hormones on cell membranes in the rat uterus. III. The surface carbohydrates at the apex of the luminal epithelium

Histochemical techniques, including radioisotope histochemistry, have been used to investigate the nature of the surface carbohydrates at the apex of cells of the luminal epithelium of the rat uterus under various hormonal conditions. Binding of ruthenium red was quantitatively similar in ovariectomized rats without further treatment and in those given three daily injections of progesterone. Ruthenium red binding was significantly lower after 3 days treatment with estradiol, and also after 3 days treatment with progesterone with an additional dose of estradiol on day 3, a regime known to produce an epithelium receptive to the implanting blastocyst. Binding of concanavalin A (con A), whether studied by electron microscope histochemistry after incubation of tissue with con A-horseradish peroxidase, or by light microscope autoradiography after incubation with 3H-con A, was not statistically different in any of the four groups of rats. The results with ruthenium red show a reduction in net negative charge of the carbohydrates on the apical cell membrane in conditions permitting implantation: this change is not due to variations in the amounts of the neutral carbohydrates, mannose and glucose, as demonstrated by con A.

Pericytes in the stroma of the rat uterus

After ovariectomy and 3 daily injections of progesterone plus one of oestradiol-17 beta, 69% of stromal capillaries of the rat uterus became sheathed with pericytes. On Day 5 of pregnancy the value was 74% but at other times (Days 4 and 6) and with progesterone-only or not treatment less than 15% of capillaries were associated with pericytes. This period of pericyte presence coincides with the time when implantation is possible.

The development of squamous cell metaplasia in human bronchial epithelium by light microscopic morphometry

Bronchial biopsies from ten subjects, including five smokers, have been examined using light microscopic morphometry. The biopsies were free from identifiable disease. Using manual point counting and a Quantimet 720 image analysing computer, a number of parameters were measured. Computer-based cluster analysis of seven of these parameters associated the subjects into three groups: visual inspection of the sections achieved the same separation. Four subjects (non-smokers) had normal epithelia: four subjects (one non-smoker, three smokers) showed mucous cell hyperplasia: two subjects (smokers) had squamous cell metaplasia. Three parameters in conjunction contained sufficient information to characterize accurately the histological appearance of the epithelia: the epithelial thickness, the volume density of intracellular mucus and the number of nuclear profiles per unit area of sectioned epithelium. Reduction of these three parameters to a linear plot closely approximated a similar reduction of the original seven parameters. These three parameters can be measured rapidly, either manually or by the Quantimet. The linear representation of these parameters provides a reproducible and objective basis for comparing specimens of bronchial epithelium.