"Should I use human, rabbit or guinea pig complement?" is the question we are asked most often. The honest answer is that the complement source is part of the assay method rather than a preference. Complement regulators cross species boundaries unevenly, so the same serum panel titered against the same strain can give a different answer depending on whose cascade supplies the killing.
So instead of arguing it from first principles, we mined our literature index for every paper that names a complement serum and recorded what it was used for: the complement species, the pathogen, the assay, and the supplier where the paper names one. The searchable table further down is that dataset. It holds 653 paper-and-source records from 546 publications and covers 12 complement species, and the rest of this post is what it shows.
One rule shapes the assay column: it records what the complement itself was used for, not every assay in the paper. A study that measured IgG by ELISA and killing by SBA is filed under the SBA, because the ELISA never saw the reagent, and a row reads "Not stated" where the paper never says what the complement did. That rule costs us rows and it is the only way the column means anything.
Why the species changes the result
Complement regulators are host-specific, which is why the species matters. Neisseria meningitidis and N. gonorrhoeae recruit human factor H through surface proteins (factor H binding protein, NspA) that engage human factor H and not the factor H of other species (Granoff 2009, Infection and Immunity), and the same protein-mimicry mechanism has been mapped structurally (Schneider 2009, Nature). A meningococcus sitting in rabbit serum therefore loses a defence it has in human serum, and rabbit-complement titers run higher than human-complement titers on the same sera. That is the effect that made complement source a documented variable in meningococcal serology (Santos 2001, Clinical and Diagnostic Laboratory Immunology), first reported for group B polysaccharide antibodies (Zollinger 1983, Infection and Immunity). For serogroups A, C, W and Y the licensure assay is the rabbit-complement one, and even there the two readouts are not interchangeable: run head to head, rSBA and hSBA correlated moderately for serogroup C and poorly for A, W-135 and Y, and a post-vaccination rSBA titer was a sensitive but non-specific predictor of an hSBA titer of 1:4 (Gill 2012, Vaccine). For serogroup B the gap is wider still, which is why the accepted correlates of protection are rSBA ≥ 1:8 with rabbit complement and hSBA ≥ 1:4 with human complement instead of one number for both (Borrow 2005, Vaccine). The bactericidal readout itself is the oldest surrogate in the field (Goldschneider 1969, Journal of Experimental Medicine).
Potency differs as much as specificity does, and it was measured early. Against antibody-sensitized sheep cells, guinea pig serum titers about seven times human serum, rabbit serum about a quarter of it, hamster, rat and dog serum about the same as it, and mouse serum about one sixtieth of it (Levy 1958, Experimental Biology and Medicine). Species also differ in which indicator cell reads them best: sheep cells plus rabbit antibody are the most sensitive system for human, monkey, dog, guinea pig and rat complement, rabbit cells read horse, cow and sheep complement better, and human cells read goat, cat and rabbit complement better (Grant 1977, American Journal of Veterinary Research). Those two papers explain most of the pattern below.
Three practical consequences follow, and the dataset shows all three:
- Human complement is used where the regulator interaction is the point. 36 of the human-complement records are explicitly hSBA, the human records concentrate on N. meningitidis (61) and N. gonorrhoeae (6), and 12 are xenotransplantation work where human complement is the effector by definition.
- Rabbit complement is used where throughput and standardization matter. It carries the rSBA (69 records across our two rabbit groups), the opsonophagocytic assays (25 baby rabbit records), the cell-lysis work (104 complement-dependent cytotoxicity records), and every HLA crossmatch record in the table (12).
- Guinea pig complement is used where potency per microlitre is the point. Hemolysis-based assays account for 28 of its 106 records and complement-enhanced neutralization for another 23, it holds most of the cholera work (6 of 11 records), and its median publication year is 1992, older than any other source in the table.
Baby rabbit and plain "rabbit" are not the same row
Baby rabbit complement is pooled from 3 to 4 week old animals whose natural antibody repertoire has not yet developed, so intrinsic killing of the target strain is low. That property is what the standardized pneumococcal OPA was built on (Romero-Steiner 1997, Clinical and Diagnostic Laboratory Immunology) and what carried into the multiplexed MOPA (Burton 2006, Clinical and Vaccine Immunology). In our dataset the baby rabbit records are the bactericidal and opsonophagocytic ones: N. meningitidis (57), S. pneumoniae (17), E. coli (8), Shigella (8), group A Streptococcus (7) and group B Streptococcus (6).
One finding worth stating plainly: not a single paper in the table writes "adult rabbit complement". 257 of the 653 records say only "rabbit complement" with no age given, and that unlabelled group is where the cell-lysis half of the literature sits, with 94 complement-dependent cytotoxicity records, 20 xenotransplantation, all 12 HLA crossmatches, and 9 where the complement's job is to lyse one cell subset out of a preparation (anti-Thy-1 or anti-CD8 antibody plus rabbit complement, before the experiment starts). Those are the assays adult rabbit complement (31060 unadsorbed, 31063 adsorbed) is sold for, and Cedarlane is the supplier named in 32 of those rows, but the table keeps them under Rabbit (age not stated) rather than inferring the age from the assay. When you copy a cytotoxicity method, check whether the paper says which rabbit material it used, because most do not.
Antibody-depleted human complement exists because native human serum cannot be the reagent
Any human serum carries the donors' own IgG, IgM and IgA, and those antibodies activate the cascade on the target organism whether or not the vaccine antibody does. That background is what stops native human serum from serving as an exogenous complement source in a regulated hSBA. Removing IgG, IgM and IgA while keeping hemolytic activity is what antibody-depleted human complement is for, and a standardized human-complement SBA has now been developed and validated on it (Matthias 2025, Vaccine), including in luminescence-based high-throughput format (Caradonna 2024, International Journal of Molecular Sciences). Our own scale-up and characterization data are in a separate post.
Only two records in the table name antibody-depleted human complement explicitly. That is a feature of the corpus and not of the reagent: the product is recent, and papers that use it usually write "IgG/IgM-depleted human complement" in a methods line our excerpt window may not reach. Treat the 123 human-complement rows as the relevant evidence pool and read the methods section.
Guinea pig complement: hemolytic potency and the vibriocidal assay
Guinea pig serum has the highest classical-pathway hemolytic activity per volume of the common laboratory species (Levy 1958, Experimental Biology and Medicine), which is why it became the standard reagent for CH50-style hemolytic titration and complement fixation. That is still what its records are: 28 of 106 are hemolysis-based assays, 6 more are the reverse hemolytic plaque assay that counts antibody-secreting cells one lysed red cell halo at a time, 5 are complement fixation, and the median year of the guinea pig set is 1992.
It has not gone away where potency is the requirement. Guinea pig complement is the complement source in the vibriocidal assay used to read cholera vaccine responses (Kim 2017, Journal of Microbiology), a protocol published in full (Son 2011, Current Protocols in Microbiology), and it appears throughout complement-enhanced virus neutralization, 23 records from varicella-zoster to SARS-CoV-2.
The other species, and what they are actually used for
Human, rabbit and guinea pig cover most published work, but they do not cover all of it. Three situations force a species match, and the table has examples of each.
A species-restricted regulator is the thing being measured. Side-by-side complement panels are the only way to see this. CD59 (HRF20) transfectants became resistant to human complement while staying sensitive to rat and guinea pig complement (Takizawa 1992, European Journal of Immunology), and both mouse DAF isoforms blocked rat complement but not human or guinea pig complement (Ohta 1999, Microbiology and Immunology). The same logic runs through the newer therapeutic work: anti-C5 antibodies were profiled against human, rabbit, rat, guinea pig and mouse complement to find out how far the cross-reactivity went (Zelek 2019, Immunology), and eculizumab turned out to inhibit human complement far more strongly than rhesus monkey complement, which matters when a monkey is the preclinical model (Hu 2025, Xenotransplantation).
The model animal's own cascade is the readout. Mouse complement is the effector in mouse-model work on schistosome killing (Mendlovic 1987, European Journal of Immunology) and Cryptococcus opsonization (Avina 2026, Infection and Immunity), and mouse complement enhanced antibody-mediated neutralization of murine cytomegalovirus, though guinea pig complement enhanced it more (Lawson 1988, Journal of General Virology). Pig complement appears where the pig is the host: swine complement destroyed rabbit-kidney cells but spared pig-kidney cells in pseudorabies work (Maeda 2002, Virus Research), and it neutralized transmissible gastroenteritis virus differently than guinea pig complement did (Woods 1987, Advances in Experimental Medicine and Biology). Canine complement plus antiganglioside antibodies lysed human tumour lines (Helfand 1996, Cellular Immunology). Monkey complement was used alongside rabbit and human complement to confirm a group B meningococcal conjugate response (Fusco 1997, Journal of Infectious Diseases), and mpox extracellular virions proved more sensitive to human and non-human primate complement than to rabbit complement (Ostrowski 2025, bioRxiv).
The assay was built for a species that cannot supply a whole cascade. Avian complement is awkward in complement fixation, and the published workaround was to combine the C1 component of chicken complement with guinea pig complement stripped of its own C1 (van Regenmortel 1985, Journal of Virological Methods). Component-level comparisons are the other reason to buy an unusual species: the C1q of human, bovine, mouse and guinea pig complement were compared directly for hemolytic and binding activity (Sasaki 1984, Biochimica et Biophysica Acta).
Mouse is the cautionary case, and it is worth knowing before you order. Mouse serum is weakly lytic to begin with, roughly one sixtieth of human serum (Levy 1958, Experimental Biology and Medicine), and it also carries a classical-pathway inhibitor that suppresses complement from other species, with 50% inhibition at under 5% mouse serum (Ratelade 2014, Molecular Immunology). Rat and mouse sera were already described as strongly anticomplementary in reconstitution mixtures in 1950 (Rice 1950, The Journal of Immunology). Two consequences: protocols that need efficient lysis of mouse lymphocytes use rabbit complement absorbed against mouse cells rather than mouse complement, and mouse disease models that need a working classical pathway inject human complement. Ask us for mouse complement when the mouse cascade itself is what you are measuring, not as a general lytic reagent.
Where a matched species is the requirement, we prepare it on request: rat, pig, canine, cynomolgus macaque, goat and hamster complement, made the same way as our rabbit and human material, clotted at room temperature, separated cold, aliquoted and frozen at -70 °C or below to preserve hemolytic activity. Two practical notes carry over from the papers above: choose the indicator cell that reads your species (Grant 1977, American Journal of Veterinary Research), and expect lower titers than guinea pig or rabbit from most of them, so plan to use more serum per well.
Who supplied the complement in these papers
108 of the 653 records name a supplier next to the complement phrase. The rest write "rabbit complement was added" and move on. Of the ones that do name it, Cedarlane accounts for 56, Pel-Freez for 22, Bio-Rad and its AbD Serotec line for 21, Equitech-Bio and Sigma-Aldrich for 3 each, and One Lambda, Rockland and Solarbio for one each; the One Lambda record is an HLA crossmatch, which fits a supplier built around tissue typing.
Filtering the table on Pel-Freez returns 81 rows rather than 22, and the difference is worth explaining. 22 of them print our name in the excerpt. The other 59 are papers that came back in a search for our name, usually because they cite us somewhere our excerpt window does not reach, so the table shows the vendor in italics for those rows instead of claiming the excerpt said it.
Two things follow. Reagent complement is a small, concentrated market, so the same handful of names recurs across three decades of methods sections. And no one can make a serious claim about vendor-level reproducibility from the published record, because 83% of these papers never say where their complement came from. Use the Vendor named filter in the table to see it for yourself, and treat "not stated in excerpt" as the default rather than as an omission by us.
Which source each assay uses
One assay per row, because most of the disagreement about complement sources comes from lumping assays together.
| Assay | Complement source the literature uses | Why |
|---|---|---|
| hSBA (MenB, gonococcus) | Antibody-depleted human | Factor H recruitment is human-specific, and donor antibodies have to be removed |
| rSBA (MenACWY, Hib, Salmonella, Shigella) | Baby rabbit | Standardized, low intrinsic killing, correlates accepted for licensure |
| OPKA (pneumococcus, GBS, GAS) | Baby rabbit | The method was built and validated on it; MOPA is the multiplexed version of the same assay |
| Vibriocidal (cholera) | Guinea pig | Potency per volume in the published method |
| CH50 and immune-hemolysis titration | Guinea pig | Highest classical-pathway titer per volume of the common species |
| Complement fixation | Guinea pig | Same potency argument, plus decades of comparable data |
| Complement-dependent cytotoxicity of cell lines and lymphocytes | Rabbit, absorbed for low background | High lytic activity on nucleated cells |
| Depleting a cell subset before an experiment (anti-Thy-1, anti-CD8, anti-CD90 plus complement) | Rabbit low-tox, or guinea pig | Lyses the targeted lymphocytes without killing the rest of the preparation |
| HLA crossmatch and lymphocytotoxicity | Rabbit | The classical tissue-typing source; all 12 crossmatch records use it |
| Complement-enhanced virus neutralization | Guinea pig or rabbit | Potency, and the target cell tolerates it |
| Xenotransplantation and complement-inhibitor work | Human, plus the donor or model species | The human cascade is what is being measured, and the model species is the control |
| Animal-model cytotoxicity or C3 deposition | The model's own species | Regulators are species-restricted, so a foreign cascade changes the answer |
The evidence table
Every row is one publication and one complement source. The excerpt is the paper's own wording around the complement phrase, with the phrase and the supplier marked, and the DOI links to the paper. Rows come from two places: papers that cite one of our complement products, and papers whose own text names a complement species, which is how pig, monkey, dog, chicken and cow complement get into a table built on a rabbit and human catalog. A supplier is named where the paper names one next to the complement, 108 of 653 records, so "Not stated in excerpt" is the majority, and competitor names appear where the paper cites them. An italic supplier name means the paper turned up in a search for that supplier without naming it in the excerpt. The assay column is what the complement was used for and nothing else: where the excerpt earns the label, the excerpt shows the words that earned it, where only the title and abstract support it the row says so, and 71 rows carry no assay label at all because the paper never says. Filter by pathogen, assay or source, sort by year, or search for your organism.
| Complement source | Pathogen | Assay | Publication | Vendor named | Excerpt |
|---|---|---|---|---|---|
| Antibody-depleted human |
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Do the protein-based meningococcal group B vaccines, 4CMenB and MenB-fHbp, elicit serum bactericidal antibody against meningococcal serogroup X clonal complex 181? International Journal of Infectious Diseases · 2026 pathogen from title/abstract |
Pel-Freez | …added to each well of the microtiter plate. a volume of 10 µl of “active” antibody depleted human complement (pel-freeze, inc., brown deer, wi) was added to all wells except the … wells for viable cfu and sample non-complement mediated lysis control, to which heat-inactivated… |
| Antibody-depleted human |
|
|
Development and validation of a standardized human complement serum bactericidal activity assay to measure functional antibody responses to Neisseria gonorrhoeae Vaccine · 2024 |
Pel-Freez | …expressing a hybridized porb (och) [18 ]. see table s3 for a complete description of pc reagents. 3.4 intrinsic sba growth assay igg/igm-depleted human complement (c′) pooled serum (pel-freez validation lot #03642) was screened for endogenous killing activity against ng strains f62, ms11, and… |
| Baby rabbit |
|
|
Divergent humoral immune signatures in response to Klebsiella pneumoniae bacteremia International Journal of Infectious Diseases · 2025 pathogen from title/abstract; assay from title/abstract |
Pel-Freez | …serum (inactivated at 56°c for 30 minutes) in 96-well u-bottom plates and incubated shaking at 37°c for 1 h. subsequently, 10 µl of baby rabbit complement (pel-freez biologics) was added to a final concentration of 10%, and plates were incubated shaking for 1 h at 37°c. all samples were… |
| Baby rabbit |
|
|
Immunogenicity of primary and booster MenACWY-TT vaccination in older adults and the importance of IgM npj Vaccines · 2025 |
Pel-Freez | y, IgM depletion markedly reduced rSBA titers, while IgG depletion had minimal impact. These findings … MenACWY-specific antibody titers were determined using the serum bactericidal assay with baby rabbit complement (rSBA) ( Pelfreez , lot: 21044-C) as described previously 15,36 |
| Baby rabbit |
|
|
Naturally acquired antibodies against 4 Streptococcus pneumoniae serotypes in Pakistani adults with type 2 diabetes mellitus PLoS ONE · 2024 pathogen from title/abstract; assay from title/abstract |
Pel-Freez | …those with and without diabetes, however, the protective capacity of antibodies differed between the two groups. … Plates were incubated for 30 minutes on a shaker (750 RPM) at room temperature, followed by the addition of 10 μL baby rabbit complement (Pel-freeze biologicals) and differentiated … |
| Baby rabbit |
|
Not stated |
The Group A Streptococcal Vaccine Candidate VAX-A1 Protects against Group B Streptococcus Infection via Cross-Reactive IgG Targeting Virulence Factor C5a Peptidase Vaccines · 2023 |
Pel-Freez | …GAS C5a peptidase may have additional benefits through some measure of cross-protection against GBS infections. … the bacteria were pre-incubated with baby rabbit complement (PelFreez, #31061) and heat-… fetal bovine serum, and 2% baby rabbit complement, with the remaining volume comprising … |
| Baby rabbit |
|
|
Three neutralizing mAbs induced by MPXV A29L protein recognizing different epitopes act synergistically against orthopoxvirus Emerging Microbes & Infections · 2023 |
Pel-Freez | …different epitopes on MPXV A29L protein were developed and showed synergistic effects against orthopoxvirus. … finally the corresponding antibody was purified by protein A agarose columns (Bio-Rad). … Neutralization of VACV EV was performed using a 10% baby rabbit complement (Pelfreez). For … |
| Baby rabbit |
|
|
The Lack of Natural IgM Increases Susceptibility and Impairs Anti-Vi Polysaccharide IgG Responses in a Mouse Model of Typhoid ImmunoHorizons · 2022 assay from title/abstract |
Pel-Freez | …factor in reducing the typhoid severity and inducing an optimal anti-ViPS IgG response to vaccination. … μg of purified polyclonal IgM purchased from Rockland Immunochemicals (Pottstown, PA). … serum in serial dilutions, 12.5 µl of baby rabbit complement (Pel-Freez Biologicals, Rogers, … |
| Baby rabbit |
|
Not stated |
A Structural Model for the Ligand Binding of Pneumococcal Serotype 3 Capsular Polysaccharide-Specific Protective Antibodies mBio · 2021 pathogen from title/abstract |
Pel-Freez | …vaccines against bacterial diseases in clinical practice worldwide, with various degrees of success. … was performed using iScript cDNA synthesis kit (Bio-Rad) according to the manufacturer’s … Baby rabbit complement (Pel-Freez) was added to HL-60 cells at a 1:5 final volume. The HL-… |
| Baby rabbit |
|
Not stated |
Broadly Reactive Human Monoclonal Antibodies Targeting the Pneumococcal Histidine Triad Protein Protect against Fatal Pneumococcal Infection Infection and Immunity · 2021 pathogen from title/abstract |
Pel-Freez | …nonvaccine serotypes and moderate efficacy against some vaccine serotypes have contributed to high disease incidence. … added, and an image was taken immediately with the ChemiDoc imaging system (Bio-Rad). … washed twice with HBSS and mixed with baby rabbit complement (Pel-Freez Biologicals) at … |
| Baby rabbit |
|
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Development and Immunogenicity of a Brazilian Glycoconjugate vaccine against Meningococcal W in a Pilot Scale Glycoconjugate Journal · 2021 |
Pel-Freez | …will need to be done to scale up the conjugation reaction and then allow the use of this conjugate in clinical trials. … Pel-Freez® baby rabbit complement lacking bactericidal activity was added. After incubation 10 µl of the mixture from each well was plated out on Columbia blood agar… |
| Baby rabbit |
|
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Evaluation of Critical Quality Attributes of a Pentavalent (A, C, Y, W, X) Meningococcal Conjugate Vaccine for Global Use Pathogens · 2021 |
Pel-Freez | …Phase 3 clinical trials in Africa and India. … The complement source was 3-4 week old rabbit complement (Pel-freez Biologicals, Rogers, AR, USA). The bacterial strains used in the rSBA assays were: serogroup A, CDC F8238, … |
| Baby rabbit |
|
|
Multicomponent Vaccines against Group A Streptococcus Can Effectively Target Broad Disease Presentations Vaccines · 2021 pathogen from title/abstract |
Pel-Freez | e generated. Further, our results showed that an OPA alone is inadequate for understanding protection from … … Frozen GAS cultures were tested with differentiated HL60 cells and 2% baby rabbit complement (Pel-Freez Biologicals) or heat inactivated complement at a bacteria:cell ratio… |
| Baby rabbit |
|
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Performance of a Four-Antigen Staphylococcus aureus Vaccine in Preclinical Models of Invasive S. aureus Disease Microorganisms · 2021 |
Pel-Freez | …SA4Ag did not prove the clinical utility of SA4Ag in the prevention of surgery-associated invasive S. aureus infection. … The reaction mixtures were then mixed with baby rabbit complement (Pel-Freez, Rogers, AR, USA) and neutrophil-like HL-60 cells (ATCC ® CCL-240™, Manassas, VA, USA). An OPA … |
| Baby rabbit |
|
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Functional antibodies to Haemophilus influenzae type B, Neisseria meningitidis , and Streptococcus pneumoniae contained in intravenous immunoglobulin products Transfusion · 2016 assay from title/abstract |
Pel-Freez | …treatment. Regular and continuous evaluation of IVIG products is necessary to maintain an optimal therapeutic effect. … Diluted Hib Eagan strain suspension (10 µL) and 10 µL of baby rabbit complement (Pel-Freeze Biologicals) were added in the 96-well microplate. The mixture was incubated for 2 … |
| Baby rabbit |
|
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Functional immune responses to twelve serotypes after immunization with a 23-valent pneumococcal polysaccharide vaccine in older adults Vaccine · 2015 pathogen from title/abstract; assay from title/abstract |
Pel-Freez | …PPSV23, in order to develop a better understanding of the immune responses induced by PPV23 in older adults. … After 30 min of incubation at room temperature with shaking, 40 μL of HL-60 cell suspension (4 × 10 5 cells per well) and 10 μL of baby rabbit complement (Pel-Freez, Brown Deer, WI, … |
| Baby rabbit |
|
Not stated |
Impact of immunization with Protein F on pulmonary clearance of nontypeable Haemophilus influenzae Vaccine · 2014 |
Pel-Freez | …from Moraxella catarrhalis β-lactamase (P≤0.05). Taken together, our results indicate that PF is a potential NTHi-vaccine candidate. … Baby rabbit complement (Pel-freez Biologicals Rogers, AR) was used as a standardized source of complement. Bacteria were pre-incubated with various titers of… |
| Mouse |
|
|
Mannoprotein Cig1 contributes to the immunogenicity of a heat-killed F-box protein Fbp1 Cryptococcus neoformans vaccine model Infection and Immunity · 2025 pathogen from title/abstract |
Pel-Freez | …utilized to further optimize the HK- fbp1 fungal vaccine as a tool in the arsenal against invasive fungal infections. … Phosphate-buffered saline pH 7.4 (PBS)-washed fungal cells were opsonized with 20% mouse complement (Pel-Freez, AK) and added to the macrophages at an effector-to-target ratio … |
| Rabbit (age not stated) | Not stated |
|
Agglutination and hemolytic crossmatching to determine transfusion reaction differences between large and small breed goats Journal of Veterinary Internal Medicine · 2023 |
Pel-Freez | ased frequencies of hemolytic reactions compared to agglutination. Significant increases in hemolysis were … correlations between crossmatches and transfusion reactions. … Commercial rabbit complement (Pel-Freez Biologicals, Rogers, AR) then was diluted in the prepared diluted goat… |
| Rabbit (age not stated) | Not stated |
|
Physicochemical and biological similarity assessment of LBAL, a biosimilar to adalimumab reference product (Humira®) Animal Cells and Systems · 2021 assay from title/abstract |
Pel-Freez | …and functionally very similar to Humira®, supporting the biosimilarity of clinical efficacy and safety. … Samples were incubated with the tmTNF-CHO cells in the presence of rabbit complement serum (Pel-Freez Biologicals, USA) at 37C for 2 h to induce cell lysis. The cell viability was … |
| Rabbit (age not stated) |
|
|
Zika Virus-Like Particle (VLP) vaccine displaying Envelope (E) protein CD loop antigen elicits protective and specific immune response in a murine model Biochemical and Biophysical Research Communications · 2020 pathogen from title/abstract |
Pel-Freez | …cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC) activities. The WHcAg CD … Infected and uninfected target cells were incubated with mouse serum samples diluted 1:10 in the presence of rabbit complement (1:20) (Pel-Freez Biological) for 90 min under standard … |
| Rabbit (age not stated) |
|
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Comparison of serum bactericidal and antibody titers induced by two Haemophilus influenzae type b conjugate vaccines: A phase III randomized double-blind study Vaccine · 2018 pathogen from title/abstract |
Pel-Freez | …of PRP-CRM 197 compared with PRP-T assessed as SBA following a three-dose primary series by … (NCT01379846). … influenzae (10 3 bacteria/well), followed by 25 µl of rabbit complement (Pel-Freez) and 25 µl of alamar Blue solution (16% alamar Blue [Trek Diagnostics],… |
Showing the 22 papers whose excerpt names Pel-Freez complement; the full table (653 rows from 546 publications) loads with JavaScript. Generated 2026-09-21 from our literature index. Excerpts are the papers’ own words around the complement phrase (marked); pathogen and assay labels come from the excerpt, or from the title and abstract where noted. An assay label is what the complement itself was used for, so a paper that also ran an ELISA or an ADCC assay is not labelled with those, and a row reads “Not stated” where the paper never says. A vendor is named where the paper names it next to the complement; an italic vendor name means the paper surfaced in a search for that supplier without naming it in the excerpt. Excerpts taken from a full-text methods section reach us lower-cased. Always confirm details in the paper.
Choosing, and then controlling
Work backwards from the readout: if your assay is a regulatory correlate, the source is already specified, so use it. If it is a research assay, pick the source whose cascade matches the biology you are measuring, then hold it constant, because complement source is a bigger lot-to-lot variable than most assay parameters and switching mid-study makes titers incomparable.
Whatever you choose, run the two controls every published method runs: a complement-only well to measure intrinsic killing of your strain, and a heat-inactivated complement well to confirm the killing is complement dependent. Screen new lots against your own strain panel before committing a study to them, and we hold multiple 5 L+ lots of baby rabbit complement so a screened lot can be reserved. Keep the reagent cold in single-use aliquots at -70 °C or below, since the components that do the work are the heat-labile ones. Hemolytic titer (CH50) on each lot tells you the reagent is active. Only your own strain control tells you it is suitable.