Thrombotic Risk Assessment in Patients with Lymphoid Neoplasm seen at the Nnamdi Azikiwe University Teaching Hospital, Nnewi, Anambra State

BACKGROUND

Venous thromboembolism (VTE) is a cause of increased morbidity and mortality in cancer patients. VTE is the second leading cause of death in cancer patients. Risk assessment models have been developed to identify patients at risk of VTE for thromboprophylaxis. Risk scores of patients in our environment have not been adequately investigated.

OBJECTIVE

The study evaluates the association of thrombotic risk assessment scores (using the modified Khorana risk assessment tool) and soluble P-selectin levels with thrombotic events in patients with lymphoid cancer.

METHODS

This is a comparative cross-sectional study conducted at Nnamdi Azikiwe University Teaching Hospital (NAUTH, Nnewi, Anambra State). Forty-five patients with lymphoid malignancy and 45 apparently healthy subjects participated in the study. The modified Khorana risk assessment score was used to assess cancer-associated thrombotic risk. Blood sample was collected for soluble P-selectin estimation. Data were analyzed with SPSS version 23.

RESULTS

The age of subjects with lymphoid neoplasm and controls were 49.1±15.8 years, and 49.6±11.1 years respectively (p = 0.548). Subjects with lymphoid neoplasm consist of 26 (57.8%) males and 19 (42.2%) females while the controls consist of 25 (55.6%) males and 20 (44.4%) females. Non-Hodgkin's lymphoma was the most frequent of lymphoid neoplasm (18, 40.0%), followed by multiple myeloma (10, 22%), CLL (9, 20%), ALL (6, 13.0%) and Hodgkin's lymphoma (2, 4.0%). Thirty-five (77.8%) subjects with lymphoid neoplasm had intermediate risk scores and 10 (22.2%) had high-risk scores. Nineteen (42.2%) of the controls had intermediate risk and 26 (57.8%) low risk. The differences in proportion were statistically significant (p < 0.001). The median (IQR) levels of soluble P-selectin were significantly higher in patients with lymphoid neoplasm (12.2 vs. 7.0ng/mL, p <0.001). Three (6.6%) patients with lymphoid malignancies had deep vein thrombosis confirmed by a Doppler ultrasound scan.

CONCLUSION

Lymphoid malignancy is associated with relatively higher thrombotic risk scores, sP-selectin levels, and venous thromboembolic events.

CONTEXTE

La thromboembolie veineuse (TEV) est une cause de morbidité et de mortalité accrues chez les patients atteints de cancer. La TEV est la deuxième cause de décès chez les patients atteints de cancer. Des modèles d’évaluation des risques ont été mis au point pour identifier les patients présentant un risque de TEV en vue d’une thromboprophylaxie. Les scores de risque des patients dans notre environnement n’ont pas été étudiés de manière adéquate.

OBJECTIF

L’étude évalue l’association des scores d’évaluation du risque thrombotique (en utilisant l’outil modifié d’évaluation du risque de Khorana) et des niveaux de P-sélectine soluble avec les événements thrombotiques chez les patients atteints d’un cancer lymphoïde.

MÉTHODES

Il s’agit d’une étude transversale comparative menée au Nnamdi Azikiwe University Teaching Hospital (NAUTH, Nnewi, État d’Anambra). Quarante-cinq patients atteints d’un cancer lymphoïde et 45 sujets apparemment sains ont participé à l’étude. Le score modifié d’évaluation du risque de Khorana a été utilisé pour évaluer le risque thrombotique associé au cancer. Un échantillon de sang a été prélevé pour l’estimation de la P-sélectine soluble. Les données ont été analysées avec SPSS version 23.

RÉSULTATS

L’âge des sujets atteints de néoplasme lymphoïde et des témoins était respectivement de 49,1±15,8 ans et 49,6±11,1 ans (p = 0,548). Les sujets atteints de néoplasme lymphoïde sont 26 (57,8 %) hommes et 19 (42,2 %) femmes, tandis que les témoins sont 25 (55,6 %) hommes et 20 (44,4 %) femmes. Le lymphome non hodgkinien était le néoplasme lymphoïde le plus fréquent (18, 40 %), suivi du myélome multiple (10, 22 %), de la LLC (9, 20 %), de la LAL (6, 13 %) et du lymphome hodgkinien (2, 4 %). Trente-cinq (77,8 %) sujets atteints de néoplasmes lymphoïdes présentaient un score de risque intermédiaire et 10 (22,2 %) un score de risque élevé. Dix-neuf (42,2 %) des témoins présentaient un risque intermédiaire et 26 (57,8 %) un risque faible. Les différences de proportion étaient statistiquement significatives (p < 0,001). Les niveaux médians (IQR) de P-sélectine soluble étaient significativement plus élevés chez les patients atteints de néoplasme lymphoïde (12,2 vs. 7,0 ng/mL, p <0,001). Trois (6,6 %) patients atteints de tumeurs lymphoïdes ont présenté une thrombose veineuse profonde confirmée par une échographie Doppler.

CONCLUSION

Les tumeurs malignes lymphoïdes sont associées à des scores de risque thrombotique, des taux de sP-sélectine et des événements thromboemboliques veineux relativement plus élevés.

Mots-clés

Malignité lymphoïde, Thrombose, P-sélectine soluble, Scores d’évaluation du risqué.

Efficacy of ultra-short, response-guided sofosbuvir and daclatasvir therapy for hepatitis C in a single-arm mechanistic pilot study

Background

World Health Organization has called for research into predictive factors for selecting persons who could be successfully treated with shorter durations of direct-acting antiviral (DAA) therapy for hepatitis C. We evaluated early virological response as a means of shortening treatment and explored host, viral and pharmacokinetic contributors to treatment outcome.

Methods

Duration of sofosbuvir and daclatasvir (SOF/DCV) was determined according to day 2 (D2) virologic response for HCV genotype (gt) 1- or 6-infected adults in Vietnam with mild liver disease. Participants received 4- or 8-week treatment according to whether D2 HCV RNA was above or below 500 IU/ml (standard duration is 12 weeks). Primary endpoint was sustained virological response (SVR12). Those failing therapy were retreated with 12 weeks SOF/DCV. Host IFNL4 genotype and viral sequencing was performed at baseline, with repeat viral sequencing if virological rebound was observed. Levels of SOF, its inactive metabolite GS-331007 and DCV were measured on days 0 and 28.

Results

Of 52 adults enrolled, 34 received 4 weeks SOF/DCV, 17 got 8 weeks and 1 withdrew. SVR12 was achieved in 21/34 (62%) treated for 4 weeks, and 17/17 (100%) treated for 8 weeks. Overall, 38/51 (75%) were cured with first-line treatment (mean duration 37 days). Despite a high prevalence of putative NS5A-inhibitor resistance-associated substitutions (RASs), all first-line treatment failures cured after retreatment (13/13). We found no evidence treatment failure was associated with host IFNL4 genotype, viral subtype, baseline RAS, SOF or DCV levels.

Conclusions

Shortened SOF/DCV therapy, with retreatment if needed, reduces DAA use in patients with mild liver disease, while maintaining high cure rates. D2 virologic response alone does not adequately predict SVR12 with 4-week treatment.

Funding

Funded by the Medical Research Council (Grant MR/P025064/1) and The Global Challenges Research 70 Fund (Wellcome Trust Grant 206/296/Z/17/Z).

Safety and immunogenicity of a self-amplifying RNA vaccine against COVID-19: COVAC1, a phase I, dose-ranging trial

BACKGROUND

Lipid nanoparticle (LNP) encapsulated self-amplifying RNA (saRNA) is a novel technology formulated as a low dose vaccine against COVID-19.

METHODS

A phase I first-in-human dose-ranging trial of a saRNA COVID-19 vaccine candidate LNP-nCoVsaRNA, was conducted at Imperial Clinical Research Facility, and participating centres in London, UK, between 19^th June to 28^th October 2020. Participants received two intramuscular (IM) injections of LNP-nCoVsaRNA at six different dose levels, 0.1-10.0μg, given four weeks apart. An open-label dose escalation was followed by a dose evaluation. Solicited adverse events (AEs) were collected for one week from enrolment, with follow-up at regular intervals (1-8 weeks). The binding and neutralisation capacity of anti-SARS-CoV-2 antibody raised in participant sera was measured by means of an anti-Spike (S) IgG ELISA, immunoblot, SARS-CoV-2 pseudoneutralisation and wild type neutralisation assays. (The trial is registered: ISRCTN17072692, EudraCT 2020-001646-20).

FINDINGS

192 healthy individuals with no history or serological evidence of COVID-19, aged 18-45 years were enrolled. The vaccine was well tolerated with no serious adverse events related to vaccination. Seroconversion at week six whether measured by ELISA or immunoblot was related to dose (both p<0.001), ranging from 8% (3/39; 0.1μg) to 61% (14/23; 10.0μg) in ELISA and 46% (18/39; 0.3μg) to 87% (20/23; 5.0μg and 10.0μg) in a post-hoc immunoblot assay. Geometric mean (GM) anti-S IgG concentrations ranged from 74 (95% CI, 45-119) at 0.1μg to 1023 (468-2236) ng/mL at 5.0μg (p<0.001) and was not higher at 10.0μg. Neutralisation of SARS-CoV-2 by participant sera was measurable in 15% (6/39; 0.1μg) to 48% (11/23; 5.0μg) depending on dose level received.

INTERPRETATION

Encapsulated saRNA is safe for clinical development, is immunogenic at low dose levels but failed to induce 100% seroconversion. Modifications to optimise humoral responses are required to realise its potential as an effective vaccine against SARS-CoV-2.

FUNDING

This study was co-funded by grants and gifts from the Medical Research Council UKRI (MC_PC_19076), and the National Institute Health Research/Vaccine Task Force, Partners of Citadel and Citadel Securities, Sir Joseph Hotung Charitable Settlement, Jon Moulton Charity Trust, Pierre Andurand, Restore the Earth.

High Cure Rates for Hepatitis C Virus Genotype 6 in Advanced Liver Fibrosis With 12 Weeks Sofosbuvir and Daclatasvir: The Vietnam SEARCH Study

BACKGROUND

Genotype 6 is the most genetically diverse lineage of hepatitis C virus, and it predominates in Vietnam. It can be treated with sofosbuvir with daclatasvir (SOF/DCV), the least expensive treatment combination globally. In regional guidelines, longer treatment durations of SOF/DCV (24 weeks) are recommended for cirrhotic individuals, compared with other pangenotypic regimens (12 weeks), based on sparse data. Early on-treatment virological response may offer means of reducing length and cost of therapy in patients with liver fibrosis.

METHODS

In this prospective trial in Vietnam, genotype 6-infected adults with advanced liver fibrosis or compensated cirrhosis were treated with SOF/DCV. Day 14 viral load was used to guide duration of therapy: participants with viral load <500 IU/mL at day 14 were treated with 12 weeks of SOF/DCV and those ≥500 IU/mL received 24 weeks. Primary endpoint was sustained virological response (SVR).

RESULTS

Of 41 individuals with advanced fibrosis or compensated cirrhosis who commenced treatment, 51% had genotype 6a and 34% had 6e. The remainder had 6h, 6k, 6l, or 6o. One hundred percent had viral load <500 IU/mL by day 14, meaning that all received 12 weeks of SOF/DCV. One hundred percent achieved SVR12 despite a high frequency of putative NS5A inhibitor resistance-associated substitutions at baseline.

CONCLUSIONS

Prescribing 12 weeks of SOF/DCV results in excellent cure rates in this population. These data support the removal of costly genotyping in countries where genotype 3 prevalence is <5%, in keeping with World Health Organization guidelines. NS5A resistance-associated mutations in isolation do not affect efficacy of SOF/DCV therapy. Wider evaluation of response-guided therapy is warranted.

OC 8491 PREPVACC: A PHASE III, MAMS ADAPTIVE PROPHYLACTIC HIV VACCINE TRIAL WITH A SECOND RANDOMISATION TO COMPARE F/TAF WITH TDF/FTC PREP

Background

There remains an urgent need for a prophylactic HIV vaccine to control generalised epidemics. PrEP has demonstrated effectiveness of 86% and is recommended by WHO; uptake is generally high, but retention is disappointing in some settings. The EDCTP2 project PrEPVacc will assess the efficacy of two combination prophylactic vaccine regimens (DNA, MVA and Env protein/adjuvant) each compared to placebo and the proportion of infections averted by F/TAF in comparison to TDF/FTC. A Registration Cohort, recruiting HIV negative volunteers at risk of HIV will precede the trial.

Methods

The PrEPVacc partnership agreed that 70% vaccine efficacy had public health relevance. The trial uses nstage software for multi-arm, multi-stage designs (MAMS) and the averted infections ratio (AIR) methodology with participants randomised (i) 1:1:1 to active product or placebo (ii) 1:1 to TDF/FTC : F/TAF until week 26 (presumed peak immunogenicity). Access to PrEP in the Registration Cohort and after week 26 will be standard of care. HIV seroconversions occurring between weeks 0–26 will inform the PrEP analysis, incorporating HIV incidence amongst those who do not take up PrEP locally in the Registration Cohort. Seroconversions after week 26 will inform vaccine analyses.

Results

Up to 556 participants per group affords 92% power to detect vaccine efficacy of 70% at the final analysis, assuming incidence of 4/100-person years and 10% loss with 81% and 97% power to conclude that F/TAF can avert half or more of the infections prevented by TDF/FTC if effectiveness of TDF/FTC is 70% and 80%, respectively.

Conclusion

PrEPVacc adopts a pragmatic approach to uncertainties around HIV incidence in settings where PrEP is increasingly available. This innovative adaptive trial design uses validated software to determine vaccine efficacy and a novel methodology to evaluate a new PrEP agent, overcoming the challenge of demonstrating non-inferiority when adherence to TDF/FTC is high and the number of outcome events very low.

In situ detection and analysis of laser-induced damage on a 1.5-m multilayer-dielectric grating compressor for high-energy, petawatt-class laser systems

A grating-inspection system and a damage-analysis method have been developed to measure in situ laser-induced damage on a 1.5-m tiled-grating assembly of the OMEGA EP pulse compressor during a 15-ps, 2.2-kJ energy ramp. The beam fluence at which significant damage growth occurred was determined. This is the first report on beam fluence versus laser-induced-damage growth of meter-sized multilayer-dielectric-diffraction gratings. This result was correlated to the damage-probability measurement conducted on a small grating sample and is consistent with the fluence, corresponding to 100% damage probability.

Impaction grafting with a bone-graft substitute in a sheep model of revision hip replacement

An experimental sheep model was used for impaction allografting of 12 hemiarthroplasty femoral components placed into two equal-sized groups. In group 1, a 50:50 mixture of ApaPore hydroxyapatite bone-graft substitute and allograft was used. In group 2, ApaPore and allograft were mixed in a 90:10 ratio. Both groups were killed at six months. Ground reaction force results demonstrated no significant differences (p > 0.05) between the two groups at 8, 16 and 24 weeks post-operatively, and all animals remained active. The mean bone turnover rates were significantly greater in group 1, at 0.00206 mm/day, compared to group 2 at 0.0013 mm/day (p < 0.05). The results for the area of new bone formation demonstrated no significant differences (p > 0.05) between the two groups. No significant differences were found between the two groups in thickness of the cement mantle (p > 0.05) and percentage ApaPore-bone contact (p > 0.05).

The results of this animal study demonstrated that a mixture of ApaPore allograft in a 90:10 ratio was comparable to using a 50:50 mixture.

Absorption of carbon dioxide during laparoscopy in children measured using a novel mass spectrometric technique

BACKGROUND

Carbon dioxide (CO(2)) is absorbed during pneumoperitoneum and may cause adverse haemodynamic effects. The aim of this study was to measure the elimination of exogenous CO(2) during laparoscopy in children.

METHODS

Ten children [27.6 (56.5) months; mean (SD)] undergoing laparoscopic and nine [24.5 (17.3) months] undergoing open surgery were studied. Breath samples were collected at the line for end-tidal CO(2) and analysed for (13)CO(2)/(12)CO(2) ratio expressed as deltaPDB (difference from standard), by isotope-ratio mass spectrometry. The proportion of absorbed CO(2) was calculated comparing exhaled (13)CO(2)/(12)CO(2) before and during CO(2) pneumoperitoneum.

RESULTS

(13)CO(2)/(12)CO(2) in medical CO(2) was -32.7 (2.1) deltaPDB. (13)CO(2)/(12)CO(2) in breath of patients undergoing open procedures was -24.3 (2.4) deltaPDB at the start of operation and did not change during the operation (P > 0.2). (13)CO(2)/(12)CO(2) in breath of patients undergoing laparoscopy was -21.5 (5.4) deltaPDB at the start of insufflation, and decreased during pneumoperitoneum by 2.5 (1.6) deltaPDB, indicating absorption of exogenous CO(2). The percentage of expired CO(2) absorbed rose to 15.5 (7.7)% after 30 min of pneumoperitoneum and decreased rapidly after desufflation.

CONCLUSION

After 10 min of laparoscopy 10-20% of expired CO(2) derives from the exogenous CO(2). CO(2) absorption can be measured using a simple mass spectrometric technique.

School-based telehealth: an empirical analysis of teacher, nurse, and administrator perceptions

In 1997, the University of Kansas Medical Center (KUMC) and the United School District 500 (USD 500) in Kansas City, Kansas, launched an innovative telehealth project that brought health care directly into elementary schools by interactive video technology and peripheral devices. This paper focuses on the attitudes and opinions of key players--teachers, nurses, and administrators--involved in providing the service. Research methodology involved analyzing archival data and conducting interviews with key players on the project from USD 500 and KUMC. The study highlights the difficulty in delivering health care, especially telehealth care, to underserved, urban children. The data also reveal that initial challenges and negative attitudes can be overcome to effectively deliver telehealth care in the school setting.

Epidural analgesia. Your role

For postoperative pain, epidural analgesia may be the most effective medicine. But there are a few things nurses need to know about managing the patient, including the early warning signs of complications and what to do--and what not to do--if they occur.

Identification of a novel aspartic-like protease differentially expressed in human breast cancer cell lines

Four different human breast cancer cell lines were examined to search for genes associated with tumor growth and metastasis. Each of these cell lines, MDA-MB-453, MCF-7, MDA-MB-231 and MDA-MB-435, displays different phenotypic characteristics ranging from poorly to highly tumorigenic and metastatic. The differences in gene expression profiles of these cell lines generated by differential display technique should allow one to identify candidates as putative oncogenes or tumor/metastasis suppressor genes. A novel cDNA expressed in the highly tumorigenic and metastatic cell line, MDA-MB-435, was identified and isolated by this approach. The function for this gene, designated ALP56 (aspartic-like protease 56 kDa), in tumor progression is suggested by the homology of the encoded protein to aspartic proteases, such as cathepsin D. The amino acid residues in two catalytic domains of this family are highly conserved in those domains of ALP56. Northern hybridization indicated that the expression of ALP56 is associated with growth and metastasis of MDA-MB-435 tumors in immunodeficient mice. In situ hybridization of biopsies from breast cancer and colon cancer patients indicated that ALP56 is upregulated in human primary tumors and liver metastasis. These results suggest that this novel gene correlates with human tumor progression.

School-based telemedicine: teachers', nurses' and administrators' perceptions

In 1997, a telemedicine project began in Kansas which brought health-care directly into elementary schools using interactive video-links. The project initially involved four schools, but was expanded to cover 10 schools, including two middle and one high school. We examined the organizational issues related to telemedicine links to schools. Specific attention was paid to the perceptions of the nurses, teachers and key administrators. The research involved analysing archive data and interviewing participants in the project from the schools and the medical centre. The results showed the difficulties in delivering health-care, especially by telemedicine, to under-served urban children. However, the data also revealed that these can be overcome. Once they had experienced it at first hand, almost all concerned began to see telemedicine as an effective and important asset to the delivery of health-care.

Telemedicine services to a county jail

Local and county jails rarely offer telepsychiatry services to their inmates. We have established a telepsychiatry pilot project between the Kansas University Medical Center and the Lyon County Jail in Emporia, Kansas. A total of 264 telepsychiatry consultations were conducted with jail inmates. Of these, 70 were initial evaluations and 194 were follow-up visits; only one inmate refused to be seen. Approximately one-third of all inmates were seen for psychiatric consultation within one week of their incarceration and 68% were seen within one month of incarceration. Among lessons learned during the first year of service were: the monthly demand for consultations was five times greater than projected; moderately to severely ill inmates with a broad range of psychiatric illness can be seen and treated effectively using videoconferencing; and the technology was accepted by the jail personnel and the inmates alike and integrated into the jail's routine in terms of the delivery of psychiatric care.

Results of a meta-analysis of cost-benefit research: is this a question worth asking?

We attempted a meta-analysis of telemedicine research studies of the costs associated with telemedicine. First, we performed a search of six well known databases with a variety of relevant keywords. After discarding non-English publications, books and duplicate publications resulting from the same study, we were left with 551 articles for analysis. Our second step was to separate the articles into two groups: those with and those without quantitative cost data. Only 38 articles contained any type of real data. Because many of these 38 studies proved to be inadequately designed or conducted, we were unable to perform a traditional meta-analysis. Furthermore, there were a number of disturbing features common to these studies, including the omission of the number of consultations or patients, almost non-existent longitudinal data collection and lack of uniformity in cost analyses. We conclude that it is premature for any statements to be made, either positive or negative, regarding the cost-effectiveness of telemedicine in general.

Receptor and betagamma binding sites in the alpha subunit of the retinal G protein transducin

Transmembrane receptors for hormones, neurotransmitters, light, and odorants mediate their cellular effects by activating heterotrimeric guanine nucleotide-binding proteins (G proteins). Crystal structures have revealed contact surfaces between G protein subunits, but not the surfaces or molecular mechanism through which Galphabetagamma responds to activation by transmembrane receptors. Such a surface was identified from the results of testing 100 mutant alpha subunits of the retinal G protein transducin for their ability to interact with rhodopsin. Sites at which alanine substitutions impaired this interaction mapped to two distinct Galpha surfaces: a betagamma-binding surface and a putative receptor-interacting surface. On the basis of these results a mechanism for receptor-catalyzed exchange of guanosine diphosphate for guanosine triphosphate is proposed.

Sequence, organization, and transcription of the Dlx-1 and Dlx-2 locus

There are at least five murine Dlx genes that are related to the Drosophila Distal-less homeobox gene. The Dlx genes are primarily expressed in the developing forebrain, derivatives of the cranial neural crest and restricted epidermal craniofacial and limb domains. Dlx-2 is required for differentiation of subsets of cranial neural crest and forebrain cells. Previous genomic studies have shown that Dlx-1 and Dlx-2 are linked on mouse chromosome 2, near the HoxD cluster. Here we report a detailed analysis of the nucleotide sequence (approximately 14 kb), organization, and transcription of the murine Dlx-1 and Dlx-2 locus. In addition, we show that Dlx-1 makes multiple sense transcripts and at least one antisense transcript, whereas Dlx-2 makes one major transcript. The sequence of the human Dlx-2 gene is reported and is compared to that of the murine gene. Finally, sequence analysis of the deduced protein sequences reveals several candidate functional domains.

Assembly and function of a TCR alpha enhancer complex is dependent on LEF-1-induced DNA bending and multiple protein-protein interactions

In this study we examine the molecular basis for the synergistic regulation of the minimal TCR alpha enhancer by multiple proteins. We find that reconstitution of TCR alpha enhancer function in nonlymphoid cells requires expression of the lymphoid-specific proteins LEF-1, Ets-1 and PEBP2 alpha (CBF alpha), and a specific arrangement of their binding sites in the enhancer. We show that Ets-1 cooperates with PEBP2 alpha to bind adjacent sites at one end of the enhancer, forming a ternary complex that is unstable by itself. Stable occupancy of the Ets-1- and PEBP2 alpha-binding sites in a DNase I protection assay was found to depend on both a specific helical phasing relationship with a nonadjacent ATF/CREB-binding site at the other end of the enhancer and on LEF-1. The HMG domain of LEF-1 was found previously to bend the DNA helix in the center of the TCR alpha enhancer. We now show that the HMG domain of the distantly related SRY protein, which also bends DNA, can partially replace LEF-1 in stimulating enhancer function in transfection assays. Taken together with the observation that Ets-1 and members of the ATF/CREB family have the potential to associate in vitro, these data suggest that LEF-1 can coordinate the assembly of a specific higher-order enhancer complex by facilitating interactions between proteins bound at nonadjacent sites.

Cloning of GT box-binding proteins: a novel Sp1 multigene family regulating T-cell receptor gene expression

Analysis of a T-cell antigen receptor (TCR) alpha promoter from a variable gene segment (V) revealed a critical GT box element which is also found in upstream regions of several V alpha genes, TCR enhancer, and regulatory elements of other genes. This element is necessary for TCR gene expression and binds several proteins. These GT box-binding proteins were identified as members of a novel Sp1 multigene family. Two of them, which we term Sp2 and Sp3, were cloned. Sp2 and Sp3 contain zinc fingers and transactivation domains similar to those of Sp1. Like Sp1, Sp2 and Sp3 are expressed ubiquitously, and their in vitro-translated products bind to the GT box in TCR V alpha promoters. Sp3, in particular, also binds to the Sp1 consensus sequence GC box and has binding activity similar to that of Sp1. As the GT box has also previously been shown to play a role in gene regulation of other genes, these newly isolated Sp2 and Sp3 proteins might regulate expression not only of the TCR gene but of other genes as well.