Motor co-ordination in a South Indian population of children.

AIMS: To examine the associations of motor co-ordination in Kerala, South India. METHODS: The Modified Oseretsky Test of motor co-ordination was administered to 1155 representative children during a door-to-door survey of 8-12 year olds. Reading, vocabulary and visuospatial reasoning were measured, as were height and weight. Information on medical history, socio-demographic background and behaviour was systematically collected. RESULTS: Age was the major association of motor incoordination indicating the importance of maturation. Behaviour, vocabulary, visuospatial reasoning, material deprivation, perinatal complications, chronic physical symptoms and occupational status of the father were also independently associated with motor co-ordination. Using sibling pairs, evidence of familial aggregation of motor co-ordination was found.

Limited recovery of meiotic spindles in living human oocytes after cooling-rewarming observed using polarized light microscopy.

BACKGROUND: Spindles are formed from microtubules and are exquisitely sensitive to changes in temperature. An orientation-independent polarized light microscope, the Polscope, can be used to image spindles in living oocytes allowing analysis of spindle kinetics in the living state. This study examined the effects of cooling on spindle disassembly in living human oocytes and spindle recovery after rewarming. METHODS: Oocytes were imaged continuously with the Polscope during cooling and rewarming. The quantity of microtubules in the spindles was measured by its birefringence using the Polscope. RESULTS: Spindles had completely disassembled by 5 min after cooling and recovered by 20 min after rewarming to 37 degrees C if rewarming started soon after the oocyte's temperature dropped to room temperature. However, when oocytes were cooled and kept at 33, 28 or 25 degrees C for 10 min and then warmed, it was found that warming allowed 5/5, 2/5 and 0/5 oocytes of the spindles to recover respectively. CONCLUSIONS: These results indicate that human meiotic spindles are exquisitely sensitive to alterations in temperature. The maintenance of temperature at 37 degrees C during in-vitro manipulation is important for spindle integrity and, therefore, is likely to be important for normal fertilization and subsequent embryo development.

Evaluation of the prognosis of in vitro fertilization pregnancies with initially low serum human chorionic gonadotropin levels.

OBJECTIVE: The objective of this study was to investigate the prognostic significance of initially low serum early human chorionic gonadotropin levels in in vitro fertilization pregnancies that progress to an intrauterine gestational sac. STUDY DESIGN: This retrospective cohort study compared 65 in vitro fertilization pregnancies with an initial human chorionic gonadotropin value at 4 weeks of < or =20 mIU/mL with 130 pregnancies with human chorionic gonadotropin values >20 mIU/mL. All pregnancies had a singleton intrauterine sac at 6 weeks' gestational age. Spontaneous abortion rates and pregnancy complications were compared. RESULTS: Women with a low initial serum human chorionic gonadotropin level showed a statistically significant increase in first-trimester pregnancy loss (36.5% vs 9.2%; odds ratio, 5.7; 95%; confidence interval, 2.6, 12.4; P <.0001). Once pregnancies progressed to 13 weeks, there were no significant differences. CONCLUSIONS: In vitro fertilization pregnancies with a low initial human chorionic gonadotropin value, despite progressing to a gestational sac, are at an increased risk of spontaneous abortion.

Developmental ability of human oocytes with or without birefringent spindles imaged by Polscope before insemination.

BACKGROUND: Birefringent spindles imaged with the Polscope can predict fertilization rates after intracytoplasmic sperm injection (ICSI). The present study examined the development of human oocytes with or without birefringent spindles, imaged with the Polscope before ICSI. METHODS: Oocytes were obtained from stimulated ovaries of consenting patients undergoing oocyte retrieval for ICSI. Spindles were imaged with the Polscope combined with a computerized image analysis system. After imaging and ICSI, oocytes with or without spindles were cultured separately for examination of fertilization and embryo development. A total of 1544 oocytes from 136 cycles were examined with the Polscope and inseminated by ICSI. RESULTS: Spindles were imaged in 82% of oocytes. After ICSI, more oocytes (P < 0.05) with spindles (69.4%) fertilized normally, forming 2 pronuclei, than oocytes without spindles (62.9%). At day 3, more oocytes (P < 0.01) with spindles (66.3%) developed to 4-11 cell stages than oocytes without spindles (55.4%). Significantly more (P < 0.001) oocytes with spindles developed to morula and blastocyst by day 5 (51.1 versus 30.3%) and day 6 (53.2 versus 29.3%) compared with oocytes without spindles. CONCLUSIONS: The results indicate that the presence of a birefringent spindle in human oocytes can predict not only higher fertilization rate, but also higher embryo developmental competence.

The spindle observation and its relationship with fertilization after intracytoplasmic sperm injection in living human oocytes.

OBJECTIVE: To image spindles in living human oocytes and to examine the relation between spindles and fertilization after ICSI. DESIGN: The LC polscope was used to examine spindles in an observational study of living oocytes. SETTING: Academic IVF clinic. PATIENT(S): Women being treated for infertility. INTERVENTION(S): Oocytes retrieved from patients for infertility treatment were examined before ICSI. Aged, unfertilized oocytes after IVF or ICSI were examined with polscope and confocal microscopes to compare the two methods. MAIN OUTCOME MEASURE(S): Spindle structure in living oocytes and fertilization after ICSI. RESULT(S): Spindles could be imaged in 61.4% of oocytes. More oocytes with spindles than oocytes without spindles fertilized normally after ICSI (61.8% vs. 44.2%). Spindles in most aged oocytes were partially or completely disassembled, and only a few microtubules around the chromosomes or dispersed microtubules in the cytoplasm were observed. Confocal images of immunostained spindles were almost identical to polscope images of spindle birefringence. CONCLUSION(S): Spindles in living human oocytes can be imaged by using the polscope. A birefringent spindle in human oocytes may clinically predict the quality and age of oocytes. This method also can be used to monitor spindle position during ICSI.

Predicting probabilities of pregnancy and multiple gestation from in vitro fertilization--a new model.

OBJECTIVE: To develop a statistical model that adjusts for variation between patients and adequately predicts the observed distribution of pregnancies among singletons and multiple gestations of various orders. METHODS: All in vitro fertilization (IVF) cycles from the inception of the IVF program at Women and Infants' Hospital on May 26, 1988, until December 31, 1993, were evaluated using logistic regression in selected subsets. RESULTS: A new cycle-one specific model uses three different probabilities: P1, the probability of pregnancy (predicted by age and total embryo score); P2/P1, the conditional probability of finding a second implantation in those who had become pregnant with at least one (predicted by total embryo score); and P3/P2, the conditional probability of finding a third implantation in those who had become pregnant with at least two (with no significant predictors). This is the first model to use these three adjusted probabilities. CONCLUSION: P1 increases with increasing total embryo score but decreases with increasing age. P2/P1 increases with increasing total embryo score but does not depend on age. Embryo scoring is useful because the total embryo score is a better predictor of P1 and P2/P1 than the number of embryos alone. By using patient-specific information (age and total embryo score) and cycle-specific tables, an estimate of the probability of pregnancy and multiple gestation can be provided before embryo transfer.

The prevalence and associated factors of epilepsy in children in Calicut District, Kerala, India.

To determine the prevalence of epilepsy and its association with indices of malnutrition, infection and perinatal complications in children in Calicut District, Kerala, India, a door-to-door two-stage survey was conducted in two local government districts. Among the random sample of 1172 children aged 8-12 y, 26 conformed to the definition of epilepsy giving a 5-y period prevalence of 22.2/1000. A history of perinatal complications, low BMI and recent physical symptoms were independently associated with active epilepsy. The results suggest epilepsy is highly prevalent in this population of children and that further research is needed into its cause.

Serum triple-marker screening in in vitro fertilization and naturally conceived pregnancies.

OBJECTIVE: To determine whether results of second-trimester maternal serum triple-marker screening for Down syndrome and open neural tube defects in singleton pregnancies conceived from in vitro fertilization (IVF) differ from those of pregnancies conceived spontaneously. METHODS: The screen-positive rates and triple-marker levels of patients conceiving singleton pregnancies by IVF were compared to age-adjusted standards. RESULTS: Sixty-nine singleton IVF pregnancies with maternal serum screening were identified. Twenty-one (30.4%) of the 69 IVF singleton pregnancies had a positive screen for Down syndrome compared with a 14.4% expected screen-positive rate for the maternal age distribution in our observed sample (P = .013). The screen-positive rate for open neural tube defects in the measured population was similar to anticipated values based on historic controls (5.8% in IVF patients versus 5.3% in the total population). The median levels of the triple markers were 0.95 multiples of the median (MoM) for alpha-fetoprotein (AFP), 0.90 MoM for unconjugated estriol (E3), and 1.22 MoM for hCG. CONCLUSION: The increased hCG levels as well as the slightly lower AFP and unconjugated E3 levels may contribute to the higher Down syndrome screen-positive rate in this IVF singleton population. These results may be due to the number of embryos transferred, the maternal hormonal environment of the IVF process, or other factors. Pregnancies conceived by IVF may be twice as likely to have a positive maternal serum screening test. As additional data are collected, corrected standards should be determined.

5alpha-reductase 1 and 2 expression and activity in human ovarian follicles, stroma and corpus luteum as compared to neonatal foreskin.

5alpha-Reductase is the steroidogenic enzyme which reduces testosterone to 5alpha-dihydrotestosterone. In the human two different enzymes have been described, 5alpha-reductase 1 and 2. The present investigations were undertaken to determine whether 5alpha-reductase 1 and 2 were expressed in the human ovary, and to determine the relative activity of the two enzymes in various ovarian tissues. The ovary apparently expressed mRNA for only 5alpha-reductase 1, whereas the foreskin expressed both 5alpha-reductase 1 and 2. We compared the 5alpha-reductase activity at both pH 5.5 (optimum for 5alpha-reductase 2 activity) and 8.0 (optimum for 5alpha-reductase 1 activity). 5alpha-reductase activity of foreskin at pH 5.5 was 3900 times higher than small follicles, 1500 times higher than ovarian stroma, and 240 times higher than corpora lutea (all P < 0.01). 5alpha-reductase activity of corpora lutea at pH 5.5 was 17-fold higher than that of follicles (P < 0.01) and 6.5-fold higher than that of ovarian stroma (P < 0.05). 5alpha-Reductase activity of foreskin at pH 8.0 was 93 times higher than small follicles, 51 times higher than corpora lutea, and 170 times higher than ovarian stroma (all P < 0.01). The ratio of 5alpha-reductase activity at pH 5.5 to that at pH 8.0 was higher in foreskin than in corpus luteum (P < 0.05), ovarian stroma (P < 0.01), or ovarian follicles (P < 0.01). The ratio was lower in ovarian follicles than in stroma or corpus luteum (both P < 0.05).

Early and late presentation of the ovarian hyperstimulation syndrome: two distinct entities with different risk factors.

This study was designed to identify clinical predictors for early and late ovarian hyperstimulation syndrome (OHSS). A retrospective analysis of all 592 in-vitro fertilization (IVF) cycles from the programme's inception in 1988 up to March 1993 was performed. Six patients (1.0% of cycles) had moderate or severe OHSS presenting 3-7 days post-human chorionic gonadotrophin (HCG), and four patients (0.7% of cycles) had severe OHSS presenting 12-17 days post-HCG. No patient with early OHSS went on to develop late OHSS, and no patient with late OHSS had demonstrated early OHSS. Stepwise logistic regression showed that early OHSS was predicted by the number of oocytes retrieved (range 18-46) (P = 0.0001) and the oestradiol concentration on the day HCG was given (range 12,122-24,454 pmol/l) (P = 0.0003). Late OHSS was predicted by the number of gestational sacs (range 2-3) on ultrasound 4 weeks after embryo transfer (P = 0.0001) but not by the number of oocytes or oestradiol. Early OHSS was an acute effect of the HCG administered prior to egg retrieval in women with high oestradiol and larger numbers of follicles (range 22-51). Late OHSS was induced by the rising serum concentration of HCG produced by the early pregnancy, and in this series of cases it was associated only with multiple gestation.

Dehydroepiandrosterone sulfate and anovulation increase serum inhibin and affect follicular function during administration of gonadotropins.

To test the hypothesis that testosterone (T) derived from circulating dehydroepiandrosterone sulfate (DS) or produced in excess within the anovulatory ovary is a follicular regulator capable of stimulating inhibin secretion. DS and inhibin were determined by RIA in residual serum samples from in vitro fertilization cycles and analyzed along with other parameters using analysis of variance and stepwise multiple linear regression after log transformation of the RIA data. It was predicted that the serum concentration of inhibin would be higher in women with anovulation than in normal subjects and that the serum inhibin concentration would have a positive regression coefficient on the serum DS concentration. The serum concentrations of inhibin (P < 0.01) and estradiol (P < 0.001) on the day of hCG treatment were higher in women with anovulation than in normal subjects, as was the number of oocytes retrieved (P < 0.001). The FSH and LH doses (both P < 0.005) and age (P < 0.001) were significantly lower, and the average duration of gonadotropin therapy was 1 day shorter (P < 0.001) in anovulatory patients. There was no significant difference in serum DS (P > 0.2). Regression analysis showed that serum inhibin was positively related to the number of oocytes (P < 0.001) and serum DS (P = 0.05), with an increase in anovulatory subjects (P < 0.025). The duration of treatment with gonadotropins was related positively to the patient's age (P < 0.001) and negatively to serum DS (P < 0.025), with a decrease in anovulatory subjects (P < 0.025). The number of oocytes obtained was negatively related to age (P < 0.001) and positively to serum DS (P < 0.005). These data are consistent with a stimulatory effect of follicular T derived from either circulating DS or the anovulatory ovary, which affects the secretion of inhibin, the duration of gonadotropin treatment, and the number of oocytes retrieved.

Testosterone, a follicular regulator: key to anovulation.

To study the interrelationships of steroids within the follicle, combined 6-h infusions of [3H]dehydroepiandrosterone sulfate and [14C] testosterone ([14C]T) were performed in four normal women treated with menotropins who were undergoing medically indicated surgery. The concentrations of tracer and/or nonisotopic dehydroepiandrosterone sulfate, androst-5-ene-3 beta,17 beta-diol sulfate, androst-5-ene-3 beta,17 beta-diol, dehydroepiandrosterone, androstenedione, T, dihydrotestosterone, estrone (E1), and estradiol (E2) were determined in arterial and venous blood and follicular fluid. The log-transformed product/precursor ratio of [3H]dihydrotestosterone/[3H]T in follicular fluid was negatively correlated with the log-transformed follicular concentrations of E1 (P = 0.01) and E2 (P = 0.02), suggesting a reciprocal relationship between 5 alpha-reductase and follicular E1 and E2. E2 and T were positively correlated in follicular fluid (r = 0.84; P = 0.0003), suggesting a stimulatory action of follicular T on aromatase. These findings along with extensive published data suggest that follicular T functions as a follicular regulator, enhancing follicular aromatase activity when adequate amounts of FSH are available. These conclusions have important implications with regard to mechanisms for selecting the dominant follicle and producing atresia in the remaining cohort of follicles, and they describe a final common path in the pathophysiology of anovulation.

Plasma dehydroepiandrosterone sulfate serves as a prehormone for 48% of follicular fluid testosterone during treatment with menotropins.

Evidence has suggested that dehydroepiandrosterone sulfate (DS) is a prehormone for ovarian steroidogenesis. To study this hypothesis, combined 6-h infusions of [3H]dehydroepiandrosterone sulfate and [14C]testosterone ([14C]T) were performed in four normal women treated with menotropins who were undergoing medically indicated surgery, and the data were compared to those from nine normal women. The concentrations of tracer and nonisotopic DS, androst-5-ene-3 beta,17 beta-diol sulfate (delta 5diolS), androst-5-ene-3 beta,17 beta-diol (delta 5diol), dehydroepiandrosterone (D), androstenedione (delta 4A), and T were determined in arterial and venous blood and in follicular fluid. From these data, the concentrations and fractions of steroids in the follicular fluid that were derived from DS were calculated from the specific activity of intravascular DS and the concentrations of follicular fluid tracer steroids and their specific activities. The fractions of T (0.48), delta 5diol (0.31), delta 5diolS (0.42), and D (0.25) in follicular fluid arising from circulating DS were similar and were not significantly different from that of follicular DS arising from circulating DS (0.32). However, the fraction of follicular fluid delta 4A (0.041) was significantly less (P < 0.01), and the fractions of intrafollicular estrone and estradiol arising from DS were both less than 0.04. The mean MCR of DS in the women treated with menotropins of 22.0 +/- 3.5 L/day (mean +/- SE) was significantly higher than the normal control value. These findings elucidate an important mechanism of adrenal/ovarian interaction at the level of steroidogenesis; circulating DS serves as a prehormone for the production of intrafollicular delta 5diolS, delta 5 diol, D, and T.

Steroid sulfatase in the human ovary and placenta: enzyme kinetics and phosphate inhibition.

In 5 placental homogenates the Km of steroid sulfatase for DHEA sulfate increased from 15.4 in Tris buffer to 26.8 microM in phosphate (both buffers 0.1 M, pH 7.4), P less than 0.05. In 3 pooled ovarian preparations the Km increased from 14.3 microM in Tris to 33.0 microM in phosphate, P less than 0.01. There was no significant difference between the ovarian and placental values for Km in either Tris or phosphate (P greater than 0.5), and the increase in the Km produced by phosphate in ovarian tissue was not significantly different from that in the placenta (P greater than 0.5). In the placentas the Vmax in Tris was 1420 pmol/min/mg protein and this fell to 523 pmol/min/mg protein in phosphate (P less than 0.005). The Vmax was 50-fold higher in the placenta than in the ovary in either Tris or phosphate (both P less than 0.001). In the ovary, the Vmax was 27.6 pmol/min/mg protein in Tris and 11.0 pmol/min/mg protein in phosphate (P less than 0.05). The reduction of Vmax produced by phosphate in the ovary was not significantly different from that in the placenta (P greater than 0.5). The slope of the 1/v vs 1/S plot (Km/Vmax) increased 4.7-fold in the placentas and 5.8-fold in the ovaries in phosphate over that in Tris (both P less than 0.001); the increase in the placentas was not significantly different from that in the ovaries (P greater than 0.5). Phosphate ion acts as a mixed inhibitor of both placental and ovarian steroid sulfatase.

Metabolism of dehydroepiandrosterone sulfate (DS) in normal women and women with high DS concentrations.

In order to determine the contribution of serum dehydroepiandrosterone sulfate (DS) to estrone (E1) production in normal women and the effect of chronic elevation of the serum DS concentration on DS metabolism, four normal women and four women with high endogenous serum DS were infused with [3H]DS and [14C]E1 or [14C]testosterone for 6 h. Blood samples were analyzed for radioactivity as DS, dehydroepiandrosterone (D), androstenedione, testosterone, and dihydrotestosterone. Urine was collected for analysis of creatinine, 17-ketosteroids (17-KS), and radioactivity as estrone (E1). The serum DS of 12.4 +/- 1.44 mumol/L (mean +/- SE) in the group with high DS was higher than that of 3.96 +/- 1.0 mumol/L (1.46 +/- 0.37 micrograms/mL) in the normals (P less than 0.005). Those with high DS also had increased 17-KS (13.2 +/- 2.0 vs. 5.68 +/- 0.68 mg/day, P less than 0.025) and a higher blood production rate of DS (PBDS) (126 +/- 21 (n = 3) vs. 54.3 +/- 13.8 mmol/day, P less than 0.05) but a lower MCRDS (10.94 +/- 0.61 (n = 3) vs. 13.8 +/- 0.27 L/day, P less than 0.01) than that in normals. In the four normal women the fraction of infused DS converted to estrone ( [rho]BMDS E1) was 0.00078 +/- 0.00018, the amount of E1 produced from serum DS was 41.3 +/- 15 nmol/day, the basal plasma E1 was 102 +/- 18 pmol/L, the MCRE1 was 1340 +/- 181 L/day, the value for blood production of E1 (PBE1) was 129 +/- 12 nmol/day, and the portion of E1 derived from DS was 30.4 +/- 9.4%. Correlation analysis of the data from these eight subjects showed that 17-KS, PBDS, and the serum DS were all correlated with body surface area, body weight, and ponderal index and that 17-KS excretion, PBDS, and serum DS were all correlated with one another. The most important predictors of 17-KS excretion were serum DS (P less than 0.001) and the ponderal index (P less than 0.05).

Metabolic clearance rate of dehydroepiandrosterone sulfate, its metabolism to testosterone, and its intrafollicular metabolism to dehydroepiandrosterone, androstenedione, testosterone, and dihydrotestosterone in vivo.

At the time of surgery, women were infused with [3H]dehydroepiandrosterone sulfate ([3H]DS)/[14C]testosterone ([14C]T) for 6 h; blood samples were obtained from an artery the ovarian veins, and a peripheral vein; and fluid was obtained from ovarian follicles. Both blood and follicular fluid samples were analyzed for radioactivity as DS, dehydroepiandrosterone (D), androstenedione (delta 4A). T, and dihydrotestosterone (DHT), and the blood was also analyzed for the concentration of nonisotopic DS by RIA. In other subjects the concentrations of D and DS were measured in paired samples of blood and follicular fluid. From these data, values of 13.6 +/- 0.69 L/day four (mean +/- SE; n = 4) for MCRDS, 607 +/- 90 L/day (n = 3) for MCRT, and 0.0190 +/- 0.0089 (n = 3) for [p]DS-T (fraction of plasma DS metabolized to plasma T) were obtained. The ratio of the concentration of the tracer-labeled steroid in the follicular fluid to the concentration in the arterial plasma sample was elevated significantly above 1 for three 3H-labeled and three [14C-labeled metabolites: [3H]D (21-fold; P less than 0.001), [3H]T (81-fold; P less than 0.001), [3H]DHT (19-fold; P less than 0.001), [14C]T (4-fold; P less than 0.025), [14C]DHT (21-fold; P less than 0.01), and [14C]delta 4A (50-fold; P less than 0.001). The estimated concentrations of steroids in follicular fluid derived from DS based on specific activity calculations were as follows: [geometric mean (95% confidence limits; n)]: DS, 5600 (4800-6500 nmol/L; 12); D, 370 (88-1500 nmol/L; 10); delta 4 A, 120 (67-220 nmol/L; 12); T, 130 (39-450 nmol/L; 10); and DHT, 64 (35-120 nmol/L; 8). Comparison of these data to known follicular fluid steroid concentrations shows that DS from the intravascular pool can be used as an ovarian prehormone.

Steroid sulphatase activity in the human ovarian corpus luteum, stroma, and follicle: comparison to activity in other tissues and the placenta.

Steroid sulfatase activity was measured in 89 human samples, using dehydroepiandrosterone sulfate (DHEAS) as substrate. The lowest activity was that of follicular fluid which was significantly lower than that of other tissues tested (each P less than 0.01). The steroid sulfatase activity of ovarian tissue taken collectively (corpus luteum, stroma, and follicles) was higher than that of other tissues taken collectively (abdominal skin, uterus, and fallopian tube) (P less than 0.001), and the steroid sulfatase activity of either the follicle (P less than 0.01) or the stroma (P less than 0.05) was significantly greater than that of the corpus luteum. The geometric mean steroid sulfatase activity of the placenta was significantly higher than other tissues tested (each P less than 0.01) and was 22-fold higher than that of the follicle, the tissue with the next highest activity. These data indicate that the human ovary (particularly the stroma and follicle) is capable of utilizing DHEAS, an adrenal product, as a substrate for production of other androgens such as dehydroepiandrosterone (DHEA), androstenedione, and testosterone.

Effects of fetal sex, stage of gestation, dibutyryl cyclic adenosine monophosphate, and gonadotropin releasing hormone on secretion of human chorionic gonadotropin by placental explants in vitro.

Explants from 16 term and 6 midtrimester placentas were cultured for 6 days. Statistically significant increases in secretion of human chorionic gonadotropin occurred in control medium cultures of both term and midtrimester explants during the 6-day culture period (p less than 0.01). Statistically significant increases in secretion of human chorionic gonadotropin were produced by 2 mmol/L dibutyryl cyclic adenosine monophosphate in both the term (p less than 0.01) and the midtrimester (p less than 0.01) explants. There was no effect of gonadotropin releasing hormone. The ratio of human chorionic gonadotropin secretion from midtrimester explants to that from term explants varied under different conditions, dropping from twentyfold in day 1 cultures to elevenfold for maximum secretion produced after culture in control medium for up to 6 days. A further drop in the ratio to fourfold was observed for the maximal response to 2 mmol/L dibutyryl cyclic adenosine monophosphate treatment. Explants from term female infants produced significantly more human chorionic gonadotropin than those from term male infants (p less than 0.05), but the sex difference disappeared after stimulation with 2 mmol/L dibutyryl cyclic adenosine monophosphate.

Comparative effects of tumor necrosis factor-alpha and IL-1 beta on mitogen-induced T cell activation.

The effect of rTNF-alpha on human T cell function was examined and compared with that of rIL-1 beta by assessing the ability of each cytokine to support mitogen-induced proliferation, IL-2 production, and IL-2R expression. TNF-alpha and IL-1 beta each enhanced DNA synthesis induced by PHA or immobilized mAb to the CD3 molecular complex. In addition, each cytokine increased the number of cells entering the G1 phase of the cell cycle and augmented IL-2R expression. The combination of optimal concentrations of these factors supported these responses to a greater extent than either cytokine alone, suggesting that T cell responsiveness is independently regulated by the action of at least two separate monocyte derived cytokines. Whereas TNF-alpha had little effect, IL-1 beta augmented IL-2 mRNA expression and IL-2 production by mitogen-stimulated cells. Furthermore, IL-1 beta enhanced proliferation with increasing length of culture. Whereas TNF-alpha also enhanced proliferation late in culture, it was less effective in this regard than IL-1 beta. Thus, IL-1 beta and TNF-alpha augment mitogen-induced T cell proliferation by increasing the number of cells initially activated and by promoting subsequent cell cycle progression. They differ, however, in their capacity to promote IL-2 mRNA and IL-2 production and therefore ongoing T cell proliferation.